bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytochrome P4502E1 sensitizes to tumor necrosis factor alpha–induced liver injury through activation of mitogen-activated protein kinases in mice
Authors: Wu Defeng , Cederbaum Arthur
Published: December 2007

The goal of this study was to evaluate the role of mitogen-activated protein kinase (MAPK) in cytochrome P4502E1 (CYP2E1) potentiation of lipopolysaccharide or tumor necrosis factor alpha (TNF-α)–induced liver injury. Treatment of C57/BL/6 mice with pyrazole (PY) plus lipopolysaccharide (LPS) induced liver injury compared with mice treated with PY or LPS alone. The c-Jun N-terminal kinase (JNK) inhibitor SP600125 or p38 MAPK inhibitor SB203580 prevented this liver injury. PY plus LPS treatment activated p38 MAPK and JNK but not extracellular signal-regulated kinase (ERK). PY plus LPS treatment triggered oxidative stress in the liver with increases in lipid peroxidation, decrease of glutathione (GSH) levels, and increased production of 3-nitrotyrosine adducts and protein carbonyl formation. This oxidative stress was blocked by SP600125 or SB203580. PY plus LPS treatment elevated TNF-α production, and this was blocked by SP600125 or SB203580. Neither SP600125 nor SB203580 affected CYP2E1 activity or protein levels. Treating C57/BL/6 mice with PY plus TNF-α also induced liver injury and increased lipid peroxidation and decreased GSH levels. Prolonged activation of JNK and p38 MAPK was observed. All of these effects were blocked by SP600125 or SB203580. In contrast to wild-type SV 129 mice, treating CYP2E1 knockout mice with PY plus TNF-α did not induce liver injury, thus validating the role of CYP21E1 in this potentiated liver injury. Liver mitochondria from PY plus LPS or PY plus TNF-α treated mice underwent calcium-dependent, cyclosporine A–sensitive swelling, which was prevented by SB203580 or SP600125.

Conclusion:

These results show that CYP2E1 sensitizes liver hepatocytes to LPS or TNF-α and that the CYP2E1-enhanced LPS or TNF-α injury, oxidant stress, and mitochondrial injury is JNK or p38 MAPK dependent.
Fra‐1 regulates vimentin during Ha‐RAS‐induced epithelial mesenchymal transition in human colon carcinoma cells
Authors: Andreolas Chrysovalantis , Kalogeropoulou Margarita , Voulgari Angeliki , Pintzas Alexander
Published: December 2007

The process of epithelial mesenchymal transition, whereby cells acquire molecular alterations and fibroblastic features, is a fundamental process of embryogenesis and cancer invasion/metastasis. The mechanisms responsible for epithelial mesenchymal transition remain elusive. Human tumors frequently establish constitutively activated RAS signaling, which contributes to the malignant phenotype. In an effort to dissect distinct RAS isoform specific functions, we previously established human colon cell lines stably overexpressing activated Harvey‐RAS (Ha‐RAS) and Kirsten‐RAS (Ki‐RAS). Using these, we observed that only oncogenic Ha‐RAS overexpression resulted in morphologic and molecular changes suggestive of epithelial to mesenchymal transition. We showed that vimentin, a key molecule of epithelial mesenchymal transition, was differentially regulated between Ha‐RAS and Ki‐RAS leading to a Ha‐RAS specific induction of a migrative phenotype and eventually epithelial to mesenchymal transition. We demonstrated that the AP‐1 sites in vimentin promoter could be involved in this regulation. A potential role of FRA‐1 was suggested in the regulation of vimentin during the Ha‐RAS‐induced epithelial to mesenchymal transition, in association with colon cell migration. Our results therefore propose that in colon cells, the induction of epithelial mesenchymal transition by oncogenic Ha‐RAS could occur through the overexpression of proteins like FRA‐1 and vimentin. © 2007 Wiley‐Liss, Inc.
Onium salt reduces the inhibitory polymerization effect from an organic solvent in a model dental adhesive resin
Authors: Ogliari Fabrício A. , Ely Caroline , Lima Giana S. , Conde Marcus C. M. , Petzhold Cesar L. , Demarco Flávio F. , Piva Evandro
Published: December 2007

This study evaluated the effect of organic solvent concentration on the polymerization kinetics for a model dental adhesive resin containing a ternary photoinitiator system. A monomer blend based on the bis‐GMA, TEGDMA, and HEMA was used as a model dental adhesive resin, which was polymerized using a binary system [camphorquinone (CQ) and ethyl 4‐dimethylamine benzoate (EDAB)] and a ternary system [CQ, EDAB, and diphenyliodonium hexafluorphosphate (DPIHFP)]. Additionally, these blends had 0, 10, 20, 30, and 40 wt % ethanol added. Real‐time Fourier transform infrared spectroscopy was used to investigate the polymerization reaction over photoactivation time. Data were plotted, and Hill's three‐parameter nonlinear regression was performed for curve fitting. The addition of a solvent to the monomer blends decreased the polymerization kinetics, directly affecting the rate of polymerization, delaying vitrification, and attenuating the Trommsdorf effect. The introduction of DPIHFP displayed a strong increase in reaction kinetics, reducing the solvent inhibition effect. After 10 s of photoactivation, the binary system obtained in 0, 10, 20, 30, and 40% of ethanol, a degree of conversion of 44.6, 26.3, 13.4, 1.15, and 0.0%, respectively, whereas when a ternary system was used, the values were 54.6, 40.5, 27.4, 14.5, and 3.4%. An improvement was observed in the polymerization kinetics of a model dental adhesive resin when using a ternary photoinitiation system, making the material less sensitive to the residual presence of a solvent before photoactivation. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Persistent stickiness of viscous capture threads produced by araneoid orb‐weaving spiders
Authors: Opell Brent D. , Schwend Harold S.
Published: December 2007

The most commonly encountered spider orb‐webs rely on sticky, viscous capture threads to retain prey. These threads are composed of supporting fibers covered by a complex aqueous solution that forms a series of droplets, each with a glycoprotein granule that confers adhesion. This adhesive system normally functions for less than a day before being replaced. Despite their ephemeral nature, we found that the stickiness of viscous threads persists for much longer. When measured over the course of 7 days, small decreases in the adhesion of Larinioides cornutus threads were not statistically significant. Threads of Araneus marmoreus, Argiope trifasciata, and Metepeira labyrinthea were aged for 8–10 months and remeasured under environmental conditions similar to those under which initial measurements were made. When returned to humidity similar to that under which measurements were initially made, neither the droplet volumes nor the stickiness of aged threads differed significantly from those of newly spun threads. These observations indicate that when viscous threads are protected from contamination, the compounds responsible for their hydrophilic and adhesive properties do not degrade easily. J. Exp. Zool. 309:11–16, 2008. © 2007 Wiley‐Liss, Inc.
Genetic analysis of the hypervariable region of the human astrovirus nsp1a coding region: Design of a new RFLP typing method
Authors: Guix Susana , Caballero Santiago , Fuentes Cristina , Bosch Albert , Pintó Rosa M.
Published: December 2007

Human astroviruses (HAstV) are causative agents of viral gastroenteritis worldwide. A hypervariable region (HVR) is located close to the C‐terminus of the nsP1a, and recent data support the involvement of the HVR‐containing nonstructural protein in viral RNA replication processes, suggesting a correlation between variability in this region and pathogenic properties. The HVR of the C‐terminal nsP1a coding region of 104 wild‐type and reference isolates of HAstV was sequenced. A phylogenetic analysis was performed to identify different genotypes, and a restriction fragment length polymorphism (RFLP) method was designed. An extensive nucleotide and deduced amino acid sequence variability was observed, as well as many insertions and deletions that retained the reading frame. The resultant phylogenetic tree supported the subdivision of HAstV into the two previously described major genetic groups, genogroup A and B, and the identification of 12 genotypes (9 within genogroup A, and 3 within genogroup B), which could be identified by RFLP. A correlation analysis was performed between genotype information and viral load using information from 35 clinical samples. Significant differences were observed between the viral load in clinical samples and certain HAstV genotypes that belonged to the same serotype, confirming the influence of C‐terminal nsP1a variability on the viral replication phenotype. The use of the new RFLP typing method based on the HVR of the C‐terminal nsP1a coding region by diagnosticians would help to understand the relationship between different genotypes and the severity of the gastroenteritis. J. Med. Virol. 80:306–315, 2008. © 2007 Wiley‐Liss, Inc.
Detection of a new mumps virus genotype during parotitis epidemic of 2006–2007 in the State of São Paulo, Brazil
Authors: Santos C.L.S. , Ishida M.A. , Foster P.G. , Sallum M.A.M. , Benega M.A. , Borges D.B. , Corrêa K.O. , Constantino C.R.O. , Afzal M.A. , Paiva T.M.
Published: December 2007

Nucleotide sequence analyses of the SH gene of 18 mumps virus isolates collected in the 2006–2007 parotitis epidemic in the state of São Paulo identified a new genotype, designated genotype M. This new designation fulfills all the parameters required to define a new mumps virus genotype. The parameters were established by an expert panel in collaboration with the World Health Organization (WHO) in 2005. This information will enhance the mumps virus surveillance program both at the national and global levels. J. Med. Virol. 80:323–329, 2008. © 2007 Wiley‐Liss, Inc.
Globalization of the HR function: The next step in HR's transformation?
Authors: Piercy Karen , Vernon Philip
Published: December 2007

A study confirms HR's progress in moving from a transactional function to a strategic partner. The function now faces pressures to globalize by adopting service delivery models that better rationalize costs, leverage common technology and processes, and focus resources on global HR processes that can create competitive differentiation for the enterprise. The authors discuss five service delivery models along a continuum of commonality of business needs, and present four cases of global companies that found the best fit for their needs. Key determinants include financial considerations, HR service requirements, and cultural readiness. © 2008 Wiley Periodicals, Inc.
Best practices in the Japanese software market
Authors: Ojala Arto , Tyrväinen Pasi
Published: December 2007

Globalization of software markets is driving software firms to seek market share and growth opportunities from leading software markets in the world. As the second largest software market, Japan offers high growth potential for foreign software firms. In Japan, the information and communication technology industry is the largest market sector, and the size of the software market in Japan was US$131.8 billion in 2004. Despite great opportunities in the Japanese market, entering the market and conducting successful business there can be difficult due to cultural differences between Japan and Western countries. In this multi‐case study we focus on nine software firms in order to examine the best practices which these firms perceived as critical for successful operations in the Japanese software market.

The findings from this study indicate that software firms operating in business‐to‐business market niches rank factors related to the personal marketing of products higher than factors related to mass marketing. These firms value competence in the Japanese language, the general competence of personnel, and customer satisfaction and honesty more than they value brand image. These software companies also emphasize the value of an integrated product strategy that combines the uniqueness and quality of the product with packaging and product adaptation or customization. © 2008 Wiley Periodicals, Inc.
It's you, not them: Strategies for becoming a smarter leader
Authors: Sloan Karlin
Published: December 2007

We have moved from the Information Age into the Age of Interdependence, in which smart leadership entails asking the right questions rather than knowing all the answers. Drawing on the concept of Appreciative Inquiry, the author discusses how to develop the appreciative attitude and mind‐set needed to lead in the midst of complexity. Four strategies are presented: applying the “appreciative eye” to work from the positive, letting go of being the expert, embracing curiosity, and practicing the art of inquiry. The article includes techniques to discover leadership strengths and prepare less‐than‐receptive teams for positive change.

This article is reprinted from the book, Smarter, Faster, Better: Strategies for Effective, Enduring, and Fulfilled Leadership, by Karlin Sloan, with Lindsey Pollak (Jossey‐Bass, 2006). © 2006 Karlin Sloan.
The postoperative recurrence and the occurrence of second primary carcinomas in patients with early gastric carcinoma
Authors: Yamamoto Manabu , Yamanaka Takeharu , Baba Hideo , Kakeji Yoshihiro , Maehara Yoshihiko
Published: December 2007

Objective

Early gastric cancers have recently become more prevalent, and therefore, characterization of the features of patients who develop recurrence and second cancers is necessary for the development of effective postoperative follow‐up strategies.

Methods

We evaluated the clinicopathological features and the timing of the development of both recurrence and second primary cancer after surgery for early gastric cancer in 671 patients.

Results

The incidence rate of recurrent early gastric cancer was 2.1%, and the incidence rate of second primary cancer was 4.8%, with an associated death rate of 3.3%. Most multiple primary cancers cases involved the colorectum and the lung. A multivariate analysis of overall survival identified multiple primary cancers, age, and sex as prognostic factors for early gastric cancer. The average interval from surgery to diagnosis of recurrence was identified as 3.4 ± 2.1 years. The average interval for peritoneal recurrence was shorter than that for hematogenous recurrence (P < 0.05). The average interval from diagnosis of early gastric cancer to diagnosis of the second primary cancer was 7.1 ± 4.6 years.

Conclusion

Patients with early gastric cancer, particularly patients who are males, elderly and have lymphatic involvement, tend to have a greater risk of developing a second primary cancer and recurrence, respectively. J. Surg. Oncol. 2008;97:231–235. © 2007 Wiley‐Liss, Inc.
Validated reversed phase LC method for quantitative analysis of polymethoxyflavones in citrus peel extracts
Authors: Wang Zhenyu , Li Shiming , Ferguson Stephen , Goodnow Robert , Ho Chi‐Tang
Published: December 2007

Polymethoxyflavones (PMFs), which exist exclusively in the citrus genus, have biological activities including anti‐inflammatory, anticarcinogenic, and antiatherogenic properties. A validated RPLC method was developed for quantitative analysis of six major PMFs, namely nobiletin, tangeretin, sinensetin, 5,6,7,4′‐tetramethoxyflavone, 3,5,6,7,3′,4′‐hexamethoxyflavone, and 3,5,6,7,8,3′,4′‐heptamethoxyflavone. The polar embedded LC stationary phase was able to fully resolve the six analogues. The developed method was fully validated in terms of linearity, accuracy, precision, sensitivity, and system suitability. The LOD of the method was calculated as 0.15 μg/mL and the recovery rate was between 97.0 and 105.1%. This analytical method was successfully applied to quantify the individual PMFs in four commercially available citrus peel extracts (CPEs). Each extract shows significant difference in the PMF composition and concentration. This method may provide a simple, rapid, and reliable tool to help reveal the correlation between the bioactivity of the PMF extracts and the individual PMF content.
Mechanical and optical properties of Lu2O3 host-ceramics for Ln3+ lasants
Authors: Kaminskii A A , Akchurin M Sh , Becker P , Ueda K , Bohatý L , Shirakawa A , Tokurakawa M , Takaichi K , Yagi H , Dong J , Yanagitani T
Published: December 2007

Micro-hardness and fracture toughness, as well as linear optical properties (full transmission spectrum and refractive index dispersion) of fine-grained Lu2O3 ceramics fabricated by VSN method are presented.
Out in the open: How team leaders can deal with sensitive issues
Authors: Lindoerfer Dennis
Published: December 2007

A wide range of sensitive issues can emerge in a team environment, and the range of causes can be equally wide. Such issues can threaten a team's viability and the quality of the final work product. Team leaders may need to intervene when such situations develop, and once they have decided to intervene, they need to know how best to do so.
Tapping in: How leaders can become effective networkers
Authors: Grayson Curt , Baldwin David
Published: December 2007

In today's organizations, networking is essential to effective leadership. Leaders who are skilled networkers have access to the people, information, and resources needed to solve problems and create opportunities. Leaders who neglect their networks are missing out on a critical component of their role as leaders.
Amphiphilic Comb‐Like Polymers Based on Poly(oxyethylene)s as Drug‐Delivery Carriers
Authors: Kim Ki‐Hyun , Lee Jong‐Chan , Lee Jonghwi
Published: December 2007

Comb‐like polymers with biocompatible oxyethylene backbones and amphiphilic side groups were synthesized via polymer‐analogous reactions. Using these polymers, indomethacin‐loaded polymeric micelles were fabricated with various drug‐to‐polymer weight ratios using the oil‐in‐water emulsion technique. In addition, the size, size distribution, CMC, drug‐loading content, and entrapment efficiency of the polymeric micelles were analyzed. The volume‐weighted diameters of polymeric micelles ranged from 10 to 140 nm and were narrowly distributed for passive targeting drug delivery. The CMCs were lower (≈10−8 M) than for conventional surfactants and block copolymers.

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Theoretical and experimental approaches of bacteria‐biomaterial interactions
Authors: Missirlis Y.F. , Katsikogianni M.
Published: December 2007

About the influence of substrate roughness and spray particle size on the adhesion of thermal spray coatings

Bacterial adhesion to surfaces is a complicated process influenced by many factors including the bacteria (surface energy and charge, molecular details), the substratum surface (chemical composition, roughness, configuration, surface energy and charge) and environmental factors (serum proteins, flow conditions, temperature, bacterial concentration, time of exposure, antibiotics). The models that have been proposed for the quantitative prediction of bacteria‐material interactions are based on colloidal theories and macromolecular binding considerations. Two categories of techniques used in calculating bacterial adhesion strength and bacteria‐material interactions have been proposed: those that utilize fluid flowing against adherent bacteria and those that manipulate single bacteria (atomic force microscopy and optical tweezers), and are concisely reviewed.
Porous titanium implant materials and their potential in orthopedic surgery
Authors: Schuh A. , Luyten J. , Vidael R. , Hönle W. , Schmickal T.
Published: December 2007

In orthopedic surgery bony defects remains a challenge. In generally autologous or heterologous bony transplants can be used. Main problem is the limited amount of bone and donor site morbidity. Nowadays excellent implants and scaffolds at low costs are necessary in respect to the financial problems in our health care system and the strong financial limitations in clinical medicine. Recently a biomimetic approach, in which a porous synthetic bone substitute with properties similar to these of trabecular bone has been developed (VITOFOAM™). Aim of our study was to investigate whether cp‐Ti or Ti6Al4V or stainless steel (316L) porous metal implants achieve material properties comparable to bone.

Materials and Methods

Three cp‐Ti, Ti6Al4V and stainless steel (316L) porous metal specimen each with a pore size of 150 to 600 μm have been tested in respect to determine the Young’s Modulus E (GPa), Compression Strength (MPa) and Porosity (%) under axial compression.

Results

Young’s Modulus of the cp‐ Ti samples was in the range of 1.2 to 2.8 GPa, for Ti6Al4V 2.3 to 4.1 GPa could be achieved. Compression Strength for cp‐ Ti and Ti6Al4V ranged from 30 to 65 MPa with porosity values ranged from 71 to 80 %.

Discussion

The highly porous nature of VITOFOAM™ combined with the good biocompatibility of cp‐ Ti or Ti6Al4V and the mechanical properties make these materials ideal bone scaffolds. Trabecular bone shows pore sizes of 300–1500 μm, Young’s Modulus of 0.2–2 GPa and Compression Strength from 5–50 MPa. Porosity of spongious bone ranges from 30 to 95 %. These values are comparable to the values achieved with VITOFOAM™. Porous titanium foam with its osteoconductive properties may therefore be an ideal and cheap alternative. Implant costs can be lowered to 50 % for implants e.g. for intercorporal interbody fusion in spinal surgery. Actually further research is done to show the possibility in spinal surgery or loading technologies with Tricalciumphosphat, Hydroxylapatit, Antibiotics or Cytostatics.
Tremor dominant parkinsonism: Clinical description and LRRK2 mutation screening
Authors: Clarimón Jordi , Pagonabarraga Javier , Paisán‐Ruíz Coro , Campolongo Antonia , Pascual‐Sedano Berta , Martí‐Massó José‐Félix , Singleton Andrew B. , Kulisevsky Jaime
Published: December 2007

Tremor dominant parkinsonism (TDP) is characterized by initial prominent resting and action tremor, mild parkinsonism, unpredictable response to medication, and a better prognosis than idiopathic Parkinson's disease (PD). We report on clinical features and longitudinal course of 26 patients suffering from TDP. Mean disease duration was 6.5 ± 3 years, 61.5% of patients had a positive family history of tremor, 73% did not need drug treatment, performance of 123I‐Ioflupane SPECT showed reduced striatal tracer uptake in 65.4% of patients, and odor identification testing was pathologic in all the patients tested (n = 22). Co‐occurrence of action and resting tremor were the most annoying and disabling symptoms in all the patients, whereas rigidity and/or bradykinesia were clinically irrelevant in most of them. We also sequenced the full coding region of the Leucine‐rich repeat kinase 2 gene (LRRK2) in all patients. We found a novel Val2390Met mutation that was not found in 864 chromosomes. Our results suggest a broader clinical heterogeneity related to LRRK2 mutations and points towards TDP as a subtype within the spectrum of PD, in which disabling tremor but otherwise mild parkinsonian signs and a better prognosis are the main characteristics. © 2007 Movement Disorder Society
Executive dysfunction using behavioral assessment of the dysexecutive syndrome in Parkinson's disease
Authors: Kamei Satoshi , Hara Motohiko , Serizawa Kan , Murakami Masato , Mizutani Tomohiko , Ishiburo Motoko , Kawahara Ritsuko , Takagi Yukiko , Ogawa Katsuhiko , Yoshihashi Hirokazu , Shinbo Satoru , Suzuki Yutaka , Yamaguchi Mai , Morita Akihiko , Takeshita Jun , Hirayanagi Kaname
Published: December 2007

The objective of this study was to evaluate the executive dysfunction (ExD) in Parkinson's disease (PD) using the Behavioral Assessment of the Dysexecutive Syndrome (BADS), which provides a wide‐range assessment of ExD. The BADS and the Unified Parkinson's Disease Rating Scale (UPDRS) were investigated in 63 nondemented PD patients who revealed scores of ≥24 points on the Mini‐Mental State Examination based on the DSM‐IV. Multiple logistic regression analysis was performed to evaluate the predisposing factors to ExD, which was defined as <70 points on the age‐controlled standardized score. The total score on the UPDRS was a significant independent predisposing factor to ExD. Among the various parts of the UPDRS, part II was the significant factor for ExD. The profile scores of all subtests on the BADS in patients with ExD were significantly lower than those of patients without ExD. All profile scores decreased with severity of PD, but the changes among these scores differed. ExD in nondemented PD predisposed to a greater severity of PD, particularly as regards the activity of daily living impairment. Nondemented PD revealed wide‐range components of ExD. All components of ExD were impaired with severity of PD, but the patterns of each component exhibited variety. © 2007 Movement Disorder Society
Low‐cost Raman amplifier for CWDM systems
Authors: Fugihara Meire C. , Pinto Armando Nolasco
Published: December 2007

We propose a low‐cost Raman based amplification scheme for coarse wavelength division multiplexing systems. We also present a mathematical model suitable to be used in the design, analyze and optimization of Raman amplification systems. We validate the mathematical model with extensive comparisons with experimental results. Good agreement is obtained between numerical and experimental results. An amplification system offering more than 18 dB of gain over more than 80 nm is obtained using only four low power (up to 500 mW) semiconductor lasers. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 297–301, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23075
Analysis, realization, and measurement of broadband miniature antennas for digital TV receivers in handheld terminals
Authors: Jose Roo Ons Maria , Hauck Joachim , Buchholz Martin , Aguado‐Agelet Fernando
Published: December 2007

Handheld terminals for digital terrestrial television reception and their possible integration in GSM or 3G convergence terminals using the digital video broadcasting–handheld standard (DVB‐H) [ETSI EN 302 304, Digital Video Broadcasting (DVB); Transmission System for Handheld Terminals (DVB‐H), V1.1.1, June 2004] must support the UHF band (470–702 MHz or 470–860 MHz) as specified in the EICTA radio specification. Beside the required new receiver concepts for such battery‐powered and small terminals, there is also the request for broadband integrable antennas, which cover the mentioned frequency band. This article depicts a possible antenna structure and simulation results for the antenna performance and compares these findings with measurement results. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 293–297, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23082
Self‐calibration circuits and routines for low‐cost measuring systems
Authors: Sokoll Thorsten , Jacob Arne F.
Published: December 2007

A Low‐cost measurement system suited for in situ moisture monitoring of buildings is presented. The system consists of a robust and compact resonant microwave sensor linked to a miniaturized, low‐cost vector network analyzer. Several such systems can be controlled by a central monitoring station. The measurement accuracy is enhanced significantly by vectorial self‐calibration. To determine the magnitude and the required 360°‐phase information, an inexpensive combined gain and 180°‐phase detector is used, where the full phase information is obtained by adequately modeling the sensor's and the calibration standards' phase response. Different self‐calibration circuits are examined and their suitability is proved by comparative measurements. Finally, the system's performance is tested in a high humidity environment. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 287–293, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23083
Seven GHz high gain 0.18 μm CMOS Gilbert downconverter with wide‐swing cascode current mirrors
Authors: Tseng Sheng‐Che , Meng Chinchun , Huang Guo‐Wei
Published: December 2007

A downconversion micromixer with low‐voltage cascode current mirrors at both transconductor and load stages has been implemented using the 0.18‐μm CMOS technology in this article. This micromixer has a single‐to‐differential RF input transconductor formed by the NMOS wide‐swing cascode current mirror, while the PMOS wide‐swing cascode current mirror is also employed to improve conversion gain. A super source follower is used at the output to reduce the output impedance and to transfer more power to the load. This fully integrated downconverter has the high conversion gain of 16 dB and high LO‐to‐IF isolation of 50 dB at 7 GHz. The current consumption of the mixer core is 1 mA at 1.8 V supply voltage. Thanks to the low‐voltage operation property of the wide‐swing cascode current mirror, six transistors can be stacked within 1.8 V supply voltage. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 435–437, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23095
Emission characteristics of near‐ultraviolet two‐dimensional organic photonic crystal lasers
Authors: Dong Ying , Song Junfeng , Cheng Chuanhui , Jiang Wenhai , Yu Shukun , Du Guotong , Wang Xu
Published: December 2007

We demonstrate near‐ultraviolet frequency two‐dimensional organic‐photonic‐crystal laser using resonator structures that offer two‐dimensional distributed feedback at room temperature. The gain medium is N,N′‐di‐1‐naphthyl‐N, N′‐diphenylbenzidine (NPB) which is deposited on lithographically patterned silica structure. We observe surface emitting lasing action with the central beam normal to the surface and the far‐field emission characteristics of this laser. The devices operate in the blue spectral region, and exhibit very low threshold energies for oscillation (0.3 kW/cm2). The far field is also shown to contain information about the quality of the photonic crystal. This emission pattern offers a convenient and powerful way to evaluate the nature of laser action in such resonators. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 382–385, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23102
A class‐E CMOS RF power amplifier with cascaded class‐D driver amplifier
Authors: Jang Jaemin , Lee Hongtak , Park Changkun , Hong Songcheol
Published: December 2007

A 800‐MHz power amplifier is designed using a 0.18‐μm RF CMOS process. The voltage‐combining method is used for power combining. A transmission line transformer on a printed circuit board (PCB) is designed as a power combiner. For the switching mode power amplifier, a cascaded class‐D driver amplifier is proposed using a feedback resistor and a DC‐blocking capacitor. The power amplifier has an output power of 32.9 dBm and a power‐added efficiency of 60.25%. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 470–473, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23106
Broadband fixed phase shifter for C‐band applications
Authors: Abbosh A. M.
Published: December 2007

The design of a fixed phase shifter for C‐band applications is presented. The proposed device is composed of two parts: a quadrature 3‐dB directional coupler and the Wilkinson combiner. The quadrature coupler used in the proposed phase shifter is based on the edge‐coupled microstrip lines with a slotted ground plane to make the gap required between the coupled lines feasible. The simulated and measured results of the phase shifter show a 45° ± 5° fixed phase shift across the band 4–8 GHz with less than 1‐dB insertion loss and better than 12‐dB return loss at the centre of the C‐band. The designed device also shows a flat group delay, which enables its use in a narrow pulse transmission/reception and in the high data rate systems. The designed phase shifter has a compact size with dimensions of 30 mm × 30 mm. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 396–399, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23133
Conformational analysis of phorboxazole bis‐oxazole oxane fragment analogs by NMR spectroscopy and molecular modeling simulations
Authors: Fontana Carolina , Incerti Marcelo , Moyna Guillermo , Manta Eduardo
Published: December 2007

We present a detailed conformational study of a simplified synthetic analog of the bis‐oxazole oxane fragment found in the cytostatic agents phorboxazole A and B based on results from NMR spectroscopy and molecular modeling simulations. Complete 1H and 13C resonance assignments for the bis‐oxazole oxane system were carried out through the use of COSY, HSQC, HMBC, TOCSY, and HSQC‐TOCSY experiments, and its conformational preferences in solution were investigated by analysis of 3JHH coupling constants and NOE enhancements obtained from 1D and 2D NOESY experiments. In order to solve inconsistencies from our preliminary structural studies, simulated annealing studies were performed to thoroughly sample the phase space available to the molecule. Our results reveal that the six‐membered oxane ring, which constitutes the most important moiety regarding the three‐dimensional (3D) structure and flexibility of the analog, exists in rapid equilibrium between its two accessible chair conformers in an approximate ratio of 70:30. The information gathered from these studies will be of critical importance in our efforts to prepare novel compounds with phorboxazole‐like structure and activity. Copyright © 2008 John Wiley & Sons, Ltd.
Using indirect covariance spectra to identify artifact responses in unsymmetrical indirect covariance calculated spectra
Authors: Martin Gary E. , Hilton Bruce D. , Blinov Kirill A. , Williams Antony J.
Published: December 2007

Several groups of authors have reported studies in the areas of indirect and unsymmetrical indirect covariance NMR processing methods. Efforts have recently focused on the use of unsymmetrical indirect covariance processing methods to combine various discrete two‐dimensional NMR spectra to afford the equivalent of the much less sensitive hyphenated 2D NMR experiments, for example indirect covariance (icv)‐heteronuclear single quantum coherence (HSQC)‐COSY and icv‐HSQC–nuclear Overhauser effect spectroscopy (NOESY). Alternatively, unsymmetrical indirect covariance processing methods can be used to combine multiple heteronuclear 2D spectra to afford icv‐13C15N HSQC‐HMBC correlation spectra. We now report the use of responses contained in indirect covariance processed HSQC spectra as a means for the identification of artifacts in both indirect covariance and unsymmetrical indirect covariance processed 2D NMR spectra. Copyright © 2007 John Wiley & Sons, Ltd.
1H, 13C and 77Se NMR study of tetraselenafulvalene derivatives supported by novel H(Se)C and H(C)Se triple‐resonance experiments at natural abundance
Authors: Maloň Michal , Imakubo Tatsuro , Koshino Hiroyuki
Published: December 2007

A series of substituted tetraselenafulvalenes (TSeFs) was studied in solution using 1H, 13C and 77Se NMR spectroscopy. Chemical shifts and heteronuclear coupling constant values were determined and assigned. Novel two‐dimensional H(Se)C and H(C)Se triple‐resonance correlation experiments were applied at natural abundance in order to accomplish 13C and 77Se signal assignments. Using this approach, all the signals were unambiguously assigned and atom connectivity was established in the studied TSeF derivatives. These experiments, allowing signal assignments of quaternary carbons, may find wide application in the study of substituted TSeF and other organoselenium compounds. To the best of our knowledge, triple‐resonance experiments with proton detection have been applied to organoselenium compounds for the first time. Copyright © 2007 John Wiley & Sons, Ltd.
Characteristics and survival of 750 children diagnosed with a renal tumor in the first seven months of life: A collaborative study by the SIOP/GPOH/SFOP, NWTSG, and UKCCSG Wilms tumor study groups
Authors: van den Heuvel‐Eibrink Marry M. , Grundy Paul , Graf Norbert , Pritchard‐Jones Kathy , Bergeron Christophe , Patte Catherine , van Tinteren Harm , Rey Annie , Langford Carolyn , Anderson Jim R. , de Kraker Jan
Published: December 2007

Background

To review the clinical characteristics and survival of infants diagnosed with a primary renal tumor in the first 7 months of life.

Procedure

A retrospective data review of patients registered in five large international protocols (SFOP/GPOH/SIOP9/93‐01, UKW3 and NWTSG 4 and 5) spanning 1985–2002.

Results

750 (7.2%) of 10,430 registered patients were diagnosed with a renal tumor before age 213 days. Tumor types were Wilms tumor (WT) 58%; congenital mesoblastic nephroma (CMN) 18%; malignant rhabdoid tumor (MRTK) 8%; clear cell sarcoma (CCSK) 2%; non‐Wilms tumor (unspecified) 6%; histology unknown, 9%. CMN predominated among tumors diagnosed in the first month of life (54%) but its relative contribution diminished to <10% of all cases diagnosed after the age of 3 months (P < 0.001). Among 639 cases with specified histology and stage, 9/11 stage IV tumors were MRTK, 37/39 bilateral tumors were WT. In 626 children where surgical approach was specified, 522 had immediate nephrectomy. For all cases, 5 years event‐free survival (EFS) was 80% and overall survival (OS) 86%. Five years EFS and OS respectively by tumor type were WT (86%, 93%), CMN (94%, 96%), CCSK (49%, 51%), MRTK (16%, 16%).

Conclusion

Renal tumors diagnosed in the first 7 months of life generally have an excellent prognosis though histology is an important prognostic factor. In the first 2 months of life the prevalence of CMN is high. The relative occurrence of WT increases rapidly with age thereafter. Bilateral tumors are usually WT. Tumors with metastases at diagnosis are usually MRTK. Pediatr Blood Cancer 2008;50:1130–1134. © 2007 Wiley‐Liss, Inc.
The effect of serum withdrawal on the protein profile of quiescent human dermal fibroblasts in primary cell culture
Authors: Boraldi Federica , Annovi Giulia , Paolinelli‐Devincenzi Chiara , Tiozzo Roberta , Quaglino Daniela
Published: December 2007

The effect of serum deprivation on proliferating cells is well known, in contrast its role on primary cell cultures, at confluence, has not been deeply investigated. Therefore, in order to explore the response of quiescent cells to serum deprivation, ubiquitous mesenchymal cells, as normal human dermal fibroblasts, were grown, for 48 h after confluence, in the presence or absence of 10% FBS. Fibroblast behaviour (i.e. cell morphology, cell viability, ROS production and elastin synthesis) was evaluated morphologically and biochemically. Moreover, the protein profile was investigated by 2‐DE and differentially expressed proteins were identified by MS. Serum withdrawal caused cell shrinkage but did not significantly modify the total cell number. ROS production, as evaluated by the dihydroethidium (DH2) probe, was increased after serum deprivation, whereas elastin synthesis, measured by a colorimetric method, was markedly reduced in the absence of serum. By proteome analysis, 41 proteins appeared to significantly change their expression, the great majority of protein changes were related to the cytoskeleton, the stress response and the glycolytic pathway. Data indicate that human dermal fibroblasts in primary cell culture can adapt themselves to environmental changes, without significantly altering cell viability, at least after a few days of treatment, even though serum withdrawal represents a stress condition capable to increase ROS production, to influence cell metabolism and to interfere with cell behaviour, favouring the expression of several age‐related features.
Synthesis of novel three‐arm star azo side‐chain liquid crystalline polymer via ATRP and photoinduced surface relief gratings
Authors: Zhang Yuanyuan , Zhang Wei , Chen Xinrong , Cheng Zhenping , Wu Jianhong , Zhu Jian , Zhu Xiulin
Published: December 2007

A three‐arm star azo side‐chain liquid crystalline (LC) homopolymer, poly[6‐(4‐methoxy‐4‐oxy‐azobenzene) hexyl methacrylate] (PMMAZO), was synthesized by atom transfer radical polymerization (ATRP) method. The polymerization of 6‐(4‐methoxy‐4‐oxy‐azobenzene) hexyl methacrylate proceeded in a controlled/“living” way. A series of three‐arm star LC block copolymers (PMMAZO‐b‐PMMA) were also synthesized. The polymers were characterized by 1H NMR, gel permeation chromatograph, and UV–vis spectra, respectively. The both polymers of PMMAZO and copolymers of PMMAZO‐b‐PMMA exhibited a smetic phase and a nematic phase. As concern to the PMMAZO, the glass‐transition temperature (Tg) and phase‐transition temperature from the smetic to nematic phase and from the nematic to isotropic phase increased with the increase of molecular weight (Mn(GPC)) of PMMAZO. The phase transition temperature of the block copolymers, PMMAZO‐b‐PMMA, with the same PMMA block was similar to that of PMMAZO. However, the Tg of the PMMAZO‐b‐PMMA decreased at low azo content and then increased with the increasing Mn(GPC) when azo content was above 61.3%. With illumination of linearly polarized Kr+ laser beam at modest intensities (35 mW/cm2), significant surface relief gratings formed on PMMAZO films with different molecular weights were observed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 777–789, 2008
Synthesis, optical properties, and spectral stability of chiral dendronized binaphthyl‐containing polyfluorene derivatives
Authors: Liu Zi‐Tong , He Yan‐Mei , Wang Zhi‐Jian , Feng Yu , Fan Qing‐Hua
Published: December 2007

A new kind of chiral dendronized binaphthyl‐containing random polyfluorene derivatives bearing different contents (3.2–14.9 mol %) of Fréchet's polyether dendritic wedges have been designed and synthesized through a versatile Pd‐catalyzed Suzuki polycondensation. Their properties have been investigated by NMR, TGA, DSC, CD, UV–vis, and photoluminescence and compared to those of poly(9,9‐dihexylfluorene) (PF). It was found that attachment of Fréchet's dendritic wedges into the main chain enhanced the emission efficiency and thermal stability of the copolymers. Furthermore, different from PF, good to excellent spectral stabilities in the solid state were proven for all the dendronized chiral copolymers after a thermal annealing under air at 200 °C. The second‐generation dendronized polymer P3 bearing about 15 mol % of dendritic pendants exhibited high quantum yields in both solutions and films, and excellent thermal oxidative stability. These results demonstrated that the combination of the twisted nonplanar binaphthyl and the sterically demanding dendron could efficiently suppress the intermolecular packing and aggregation at much lower dendron contents compared to other reported dendronized polyfluorenes. Additionally, the investigation of circular dichroism spectra of these chiral dendronized polymers showed a strong Cotton effect at long wavelength (378–384 nm), indicating that the chirality of binaphthyl unit was transferred to the whole polyfluorene backbone. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 886–896, 2008
Infrared stealth and anticorrosion performances of organically modified silicate‐NiZn ferrite/polyaniline hybrid coatings
Authors: Wu K. H. , Chen P. H. , Yang C. C. , Ho W. D. , Liu C. I.
Published: December 2007

Hybrid coatings based on organically modified silicate‐Ni0.5Zn0.5Fe2O4/polyaniline were synthesized through a sol–gel technique with different NiZn ferrite/polyaniline weight ratio (1/1, 1/2, 1/5). These hybrid films were deposited via spin coating onto an aluminum alloy to improve the corrosion protection and to act as infrared stealth coatings. The effects induced by the NiZn ferrite/polyaniline hybrids on the chain dynamic, ferromagnetic behavior, infrared stealth, and anticorrosion performances of the coated samples were investigated. The rotating‐frame spin‐lattice relaxation times and scale of the spin‐diffusion path length indicated that the configuration of the hybrid films was highly cross‐linked and dense. The thermal extinction of the hybrid coatings increased with the increase in the polyaniline content. Potentio‐dynamic and salt‐spray analysis revealed that the hybrid films provided an exceptional barrier and corrosion protection in comparison with untreated aluminum alloy substrates. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 926–935, 2008
Synthesis and characterization of ethylene‐propylene‐1‐pentene terpolymers
Authors: da Silva Marco Antônio , Galland Griselda Barrera
Published: December 2007

Ethylene (E), propylene (P), and 1‐pentene (A) terpolymers differing in monomer composition ratio were produced, using the metallocenes rac‐ethylene bis(indenyl) zirconium dichloride/methylaluminoxane (rac‐Et(Ind)2ZrCl2/MAO), isopropyl bis(cyclopentadienyl)fluorenyl zirconium dichloride/methylaluminoxane (Me2C(Cp)(Flu)ZrCl2/MAO, and bis(cyclopentadienyl)zirconium dichloride, supported on silica impregnated with MAO (Cp2ZrCl2/MAO/SiO2/MAO) as catalytic systems. The catalytic activities at 25 °C and normal pressure were compared. The best result was obtained with the first catalyst. A detailed study of 13C NMR chemical shifts, triad sequences distributions, monomer‐average sequence lengths, and reactivity ratios for the terpolymers is presented. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 947–957, 2008
A novel optically active diblock copolymer composed of poly(ethylene glycol) and poly[N‐{o‐(4‐phenyl‐4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenyl}maleimide]: Synthesis, micellization behavior, and chiroptical property
Authors: Lou Liping , Jiang Liming , Sun Weilin , Shen Zhiquan
Published: December 2007

A series of optically active amphiphilic block copolymers were synthesizedby using potassium alkoxide of poly(ethylene glycol) monomethyl ether (MeOPEGO−K+) to initiate the anionic polymerization of N‐{o‐(4‐phenyl‐4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenyl}maleimide [(R)‐PhOPMI]. The PEG‐macroinitiators generated in situ in the reaction between MeOPEGOH and potassium naphthylide in tetrahydrofuran. The synthetic procedure may provide the PEG‐b‐PPhOPMI copolymers with well‐defined structure, as evidenced by gel permeation chromatography, 1H NMR, FTIR, and elemental analysis. In particular, the preparation of block copolymers having a laevorotation or dextrorotation activity was accomplished by changing the feed composition. The micellization was examined for the amphiphilic block copolymers in aqueous milieu by fluorescence spectroscopy, dynamic light scattering, and circular dichroism. The results indicate that the copolymers could form regular spherical micelles with core‐shell structure when the hydrophilic component was long enough; in contrast, the copolymers containing shorter PEG segments formed aggregates in large dimension due to the considerable interaction between hydrophobic PPhOPMI components. Also, it was found that the aggregated structure of the polymeric micelles is strongly dependent on the medium nature and the polymer concentration. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1025–1033, 2008