bluuebunny/crossref_metadata_2025 huggingface dataset:
Fruit and vegetable intake and esophageal cancer in a large prospective cohort study
Authors: Freedman Neal D. , Park Yikyung , Subar Amy F. , Hollenbeck Albert R. , Leitzmann Michael F. , Schatzkin Arthur , Abnet Christian C.
Published: August 2007

Changing patterns of esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) incidence worldwide suggest distinct etiologies. Although associations between fruit and vegetable intake and both ESCC and EAC have been found in multiple ecological and case–control studies, few prospective studies have investigated these associations. We prospectively examined these associations in 490,802 participants of the National Institutes of Health (NIH)‐AARP Diet and Health Study using Cox models adjusted for age, alcohol intake, body mass index, cigarette smoking, education, physical activity and total energy intake. We present hazard ratios and 95% confidence intervals per serving per 1,000 calories. During 2,193,751 person years of follow‐up, 103 participants were diagnosed with ESCC and 213 participants with EAC. We found a significant inverse association between total fruit and vegetable intake and ESCC risk (HR: 0.78, 95% CI: 0.67–0.91), but not EAC risk (0.98, 0.90–1.08). In models mutually adjusted for fruit and vegetable intake, the protective association with ESCC was stronger for fruits (0.73, 0.57–0.93) than for vegetables (0.84, 0.66–1.07). When we examined botanical subgroups, we observed significant protective associations for ESCC and intake of Rosacea (apples, peaches, nectarines, plums, pears and strawberries) and Rutaceae (citrus fruits). A significant inverse association between EAC and Chenopodiaceae (spinach) intake was observed. Results from our study suggest that the relation of fruit and vegetable intake and esophageal cancer risk may vary by histologic type. © 2007 Wiley‐Liss, Inc.
Occupational exposure to meat and risk of lymphoma: A multicenter case‐control study from Europe
Authors: Moore Tina , Brennan Paul , Becker Nikolaus , de Sanjosé Silvia , Maynadié Marc , Foretova Lenka , Cocco Pierluigi , Staines Anthony , Nieters Alexandra , Font Rebecca , Mannetje Andrea 't , Benhaim‐Luzon Véronique , Boffetta Paolo
Published: August 2007

Several studies have suggested an increased risk of lymphoma among workers exposed to meat, without conclusive evidence. We conducted a multicenter case‐control study during 1998–2004 in the Czech Republic, France, Germany, Ireland, Italy and Spain, including 2,007 cases of non‐Hodgkin lymphoma, 339 cases of Hodgkin lymphoma and 2,462 controls. We collected detailed information on occupational history and assessed exposure to meat in general and several types of meat via expert assessment of the questionnaires. The odds ratio (OR) of non‐Hodgkin lymphoma for ever occupational exposure to meat was 1.18 (95% confidence interval [CI] 0.95–1.46), that for exposure to beef meat was 1.22 (95% CI 0.90–1.67), and that for exposure to chicken meat was 1.19 (95% CI 0.91–1.55). The ORs were higher among workers with longer duration of exposure. An increased risk among workers exposed to beef meat was mainly apparent for diffuse large B‐cell lymphoma (OR 1.49, 95%CI 0.96–2.33), chronic lymphocytic leukemia (OR 1.35, 95% CI 0.78–2.34) and multiple myeloma (OR 1.40, 95%CI 0.67–2.94). The latter 2 types were also associated with exposure to chicken meat (OR 1.55, 95% CI 1.01–2.37, and OR 2.05, 95%CI 1.14–3.69). Follicular lymphoma and T‐cell lymphoma, as well as Hodgkin lymphoma did not show any increase in risk. Occupational exposure to meat does not appear to represent an important risk factor of lymphoma, although an increased risk of specific types of non‐Hodgkin lymphoma cannot be excluded. © 2007 Wiley‐Liss, Inc.
Functional and phenotypic characteristics of CD4+CD25highFoxp3+ Treg clones obtained from peripheral blood of patients with cancer
Authors: Strauss Laura , Bergmann Christoph , Whiteside Theresa L.
Published: August 2007

Circulating human CD4+CD25highFoxp3+ T cell populations (Treg) may contain activated CD4+CD25+ T cells interfering with Treg evaluation. To gain insights into the phenotypic and functional characteristics of Treg in patients with cancer, we have analyzed CD4+CD25high populations at the clonal level. Single‐cell sorted (SCS) CD4+CD25high T cells obtained from PBMC of normal controls (NC) or patients with squamous cell carcinoma of the head and neck (HNSCC) were plated at 1 cell/well in 96 well plates and expanded with anti‐CD3/anti‐CD28 Abs and 1,000 IU IL‐2/mL in the presence or absence of rapamycin (1 nM). All generated clones were evaluated for the phenotype by flow cyometry and suppressor function in CFSE‐based proliferation assays. Clones had heterogeneous CD25 expression levels. Cloning efficiency of CD4+CD25high T cells was low. CD25high clones expressed CTLA‐4, Foxp3, CD62L, but little GITR and suppressed proliferation of autologous CD4+CD25− responder cells. Clones of activated CD4+CD25interm./low cells expressed intermediate to high levels of GITR and HLA‐DR and did not suppress proliferation of responder cells. The number, suppressor phenotype and function of CD25high Treg clones were significantly enhanced in HNSCC patients relative to NC (p ≤ 0.001). CD4+CD25+ populations comprise phenotypically and functionally distinct subsets of CD25+ cells. Only a small fraction of these activated CD4+ T cells are potent suppressor cells characterized by high expression levels of CD25, Foxp3, CTLA‐4 and CD62L. The number of expandable Treg is increased in HNSCC patients. © 2007 Wiley‐Liss, Inc.
Patients with renal cell carcinoma nodal metastases can be accurately identified: External validation of a new nomogram
Authors: Hutterer Georg C. , Patard Jean‐Jacques , Perrotte Paul , Ionescu Constantin , de La Taille Alexandre , Salomon Laurent , Verhoest Gregory , Tostain Jacques , Cindolo Luca , Ficarra Vincenzo , Artibani Walter , Schips Luigi , Zigeuner Richard , Mulders Peter F. , Valeri Antoine , Chautard Denis , Descotes Jean‐Luc , Rambeaud Jean‐Jacques , Mejean Arnaud , Karakiewicz Pierre I.
Published: August 2007

Outcome of patients with renal cell carcinoma nodal metastases (NM) is substantially worse than that of patients with localized disease. This justifies more thorough staging and possibly more aggressive treatment in those at risk of or with established NM. We developed and externally validated a nomogram capable of highly accurately predicting renal cell carcinoma NM in patients without radiographic evidence of distant metastases. Age, symptom classification, tumour size and the pathological nodal stage were available for 4,658 individuals. The data of 2,522 (54.1%) individuals from 7 centers were used to develop a multivariable logistic regression model‐based nomogram predicting the individual probability of NM. The remaining data from 2,136 (45.9%) patients from 5 institutions were used for external validation. In the development cohort, 107/2,522 (4.2%) had lymph node metastases vs. 100/2,136 (4.7%) in the external validation cohort. Symptom classification and tumour size were independent predictors of NM in the development cohort. Age failed to reach independent predictor status, but added to discriminant properties of the model. A nomogram based on age, symptom classification and tumour size was 78.4% accurate in predicting the individual probability of NM in the external validation cohort. Our nomogram can contribute to the identification of patients at low risk of NM. This tool can help to risk adjust the need and the extent of nodal staging in patients without known distant metastases. More thorough staging can hopefully better select those in whom adjuvant treatment is necessary. © 2007 Wiley‐Liss, Inc.
Enhancement of cellular binding efficiency and cytotoxicity using polyethylene glycol base triblock copolymeric nanoparticles for targeted drug delivery
Authors: Yang Jaemoon , Cho Eun‐Jin , Seo Sungbaek , Lee Jae‐Won , Yoon Ho‐Geun , Suh Jin‐Suck , Huh Yong‐Min , Haam Seungjoo
Published: August 2007

Folate (FA) conjugated tri‐block copolymers were prepared by bioconjugation of poly ε‐caprolactonediol and various molecular weights of diamine polyethylene glycol. The synthetic tri‐block copolymers were characterized by 1H‐NMR. Three types of nanoparticles were prepared by nanoprecipitation. Their size and morphology were verified by laser scattering and transmission electron microscopy, respectively. The colloidal stability of the nanoparticles was evaluated by turbidity test. The anticancer drug doxorubicin (DOX) was encapsulated in the nanoparticles during preparation. Drug loading amounts and release behavior from prepared nanoparticles were investigated. Fluorescent‐activated cell sorting analysis and epi‐fluorescencic microscopic imaging of prepared nanoparticles exhibited good cellular uptake against target cells. FA receptor expressed OVCAR3 cells that showed higher mean fluorescence intensity than FA receptor defect A549 cells at specific polyethylene glycol chain lengths. The cell cytotoxicity of prepared nanoparticles was evaluated for receptor mediated drug delivery. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
DNA nanoparticles encapsulated in 3D tissue‐engineered scaffolds enhance osteogenic differentiation of mesenchymal stem cells
Authors: Hosseinkhani Hossein , Hosseinkhani Mohsen , Gabrielson Nathan P. , Pack Daniel W. , Khademhosseini Ali , Kobayashi Hisatoshi
Published: August 2007

In this study, we enhanced the expression of a plasmid DNA in mesenchymal stem cells (MSC) by the combination of three‐dimensional (3D) tissue‐engineered scaffold and nonviral gene carrier. To function as an enhanced delivery of plasmid DNA, acetic anhydride was reacted with polyethylenimine (PEI) to acetylate 80% of the primary and 20% of the secondary amines (PEI‐Ac80). This acetylated PEI has been demonstrated to show enhanced gene‐delivery efficiency over unmodified PEI. Collagen sponges reinforced by incorporating of poly(glycolic acid) (PGA) fibers were used as the scaffold material. DNA nanoparticles formed through simple mixing of plasmid DNA encoding bone morphogenetic protein‐2 (BMP‐2) and PEI‐Ac80 solutions were encapsulated within these scaffolds. MSC were seeded into each scaffold and cultured for several weeks. Within these scaffolds, the level of BMP‐2 expression by transfected MSC was significantly enhanced compared to MSC transfected by DNA nanoparticles in solution (in 2D tissue culture plates). Homogeneous bone formation was histologically observed throughout the sponges seeded with transfected MSC by using DNA nanoparticles after subcutaneous implantation into the back of rats. The level of alkaline phosphatase activity and osteocalcin content at the implanted sites of sponges seeded with transfected MSC by using DNA nanoparticles were significantly higher when compared with those seeded with other agents. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
High‐strength, in situ‐setting calcium phosphate composite with protein release
Authors: Weir Michael D. , Xu Hockin H.K.
Published: August 2007

The aim of this study was to develop a mechanically‐strong calcium phosphate cement (CPC) with protein release. Chitosan was used to strengthen CPC and control protein release. Mass fraction of protein release = mass of released protein/mass of total protein incorporated into the specimen. Flexural strength (mean ± sd; n = 6) of CPC containing 100 ng/mL of protein increased from 8.0 ± 1.4 MPa with 0% chitosan, to 19.8 ± 1.4 MPa with 15% chitosan (p < 0.05). The latter exceeded the reported strengths of sintered porous hydroxyapatite implants and cancellous bone. When the chitosan mass fraction was increased from 0% to 10% and 15%, protein release varied from 0.60 ± 0.03 to 0.41 ± 0.04, and to 0.23 ± 0.07, respectively (p < 0.05). When powder:liquid ratio increased from 2:1 to 3:1 and 4:1, protein release changed from 0.89 ± 0.10 to 0.41 ± 0.04, and to 0.23 ± 0.07, respectively p < 0.05. Therefore, chitosan content and powder:liquid ratio successfully controlled the protein release. The protein release mass fraction, M, was related to CPC porosity P by: M = 16.9 P4.5. In summary, a mechanically‐strong CPC with controlled protein release was formulated. Protein release was proportional to CPC porosity. The in situ‐hardening, nano‐apatite composite may have potential for bone tissue engineering, especially when both mechanical strength and controlled release of therapeutic/bioactive agents are needed. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Synthesis, characterization, and hydrolytic degradation behavior of a novel biodegradable pH‐sensitive hydrogel based on polycaprolactone, methacrylic acid, and poly(ethylene glycol)
Authors: Chao Guo Tao , Qian Zhi Yong , Huang Mei Juan , Kan Bing , Gu Ying Chun , Gong Chang Yang , Yang Jin Liang , Wang Ke , Dai Mei , Li Xing Yi , Gou Ma Ling , Tu Ming Jing , Wei Yu Quan
Published: August 2007

In this work, a new kind of biodegradable pH‐sensitive hydrogel was successfully synthesized by UV‐initiated free radical polymerization. The obtained hydrogel was characterized by 1H NMR and FTIR. Swelling behavior in different aqueous media and pH responsivity of the hydrogels were studied in detail as well. With increase in pH from 1.2 to 7.2, swelling ratio of the hydrogel increased. The morphology was observed by scanning electron microscopy, and the hydrolytic degradation behavior was also investigated in this work. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Biodegradable PCL scaffolds with an interconnected spherical pore network for tissue engineering
Authors: Izquierdo R. , Garcia‐Giralt N. , Rodriguez M.T. , Cáceres E. , García S.J. , Gómez Ribelles J.L. , Monleón M. , Monllau Joan C. , Suay J.
Published: August 2007

A technique for producing controlled interconnected porous structures for application as a tissue engineering scaffold is presented in this article. The technique is based on the fabrication of a template of interconnected poly(ethyl methacrylate) (PEMA) microspheres, the introduction of a biodegradable polymer, poly‐ϵ‐caprolactone (PCL), and the elimination of the template by a selective solvent. A series of PCL scaffolds with a porosity of 70% and pore sizes up to 200 μm were produced and characterized (both thermally and mechanically). Human chondrocytes were cultured in monolayer on bulk PCL disks or seeded into porous PCL scaffolds. Cell adhesion, viability, proliferation, and proteoglycan (PG) synthesis were tested and compared with monolayer cultures on tissue‐treated polystyrene or pellet cultures as reference controls. Cells cultured on PCL disks showed an adhesion similar to that of the polystyrene control (which allowed high levels of proliferation). Stained scaffold sections showed round‐shaped chondrocyte aggregates embedded into porous PCL. PG production was similar to that of the pellet cultures and higher than that obtained with monolayer postconfluence cultures. This shows that the cells are capable of attaching themselves to PCL. Furthermore, in porous PCL, cells maintain the same phenotype as the chondrocytes within the native cartilage. These results suggest that PCL scaffolds may be a suitable candidate for chondrocyte culture. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Oxidized NiTi surfaces enhance differentiation of osteoblast‐like cells
Authors: Michiardi A. , Engel E. , Aparicio C. , Planell J. A. , Gil F. J.
Published: August 2007

A new oxidation treatment (OT) on NiTi shape memory alloys was developed in a previous work. This OT treatment significantly decreases Ni ion release into the exterior medium, and therefore is thought to be beneficial for NiTi cytocompatibility. As to confirm this expectation, the in vitro response of MG63 osteoblast‐like cells cultured on untreated and oxidized NiTi surfaces was studied. An adhesion test at 1, 4, and 8 h of incubation was performed. Statistical differences were evidenced at 1 h of adhesion depending on the surface treatment and chemical composition of the substrate. However, at larger times of study, there were no statistically significant differences between untreated and oxidized surfaces. The proliferation test (until 9 days) showed that untreated and oxidized NiTi surfaces are not cytotoxic for MG63 cells. The differences of adhesion at short times did not affect the proliferation of MG63 cells. However, after 48 h of stimulation with ascorbic acid and dexamethasone, the MG63 cells cultured on oxidized surfaces showed higher alkaline phosphatase activity and osteocalcin levels. The improvement of osteoblast differentiation due to OT treatment could accelerate bone formation, and, therefore, could allow earlier loading of NiTi devices used in dental and orthopedic applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Structural evolution and adhesion of titanium oxide film containing phosphorus and calcium on titanium by anodic oxidation
Authors: Lin C. S. , Chen M. T. , Liu J. H.
Published: August 2007

This study investigated the microstructure evolution and defects of the titanium oxide layer containing calcium (Ca) and phosphorus (P) formed by anodic oxidation in a solution containing Ca and P compounds. Results show that the anodic film exhibited a two‐layer structure: a pore‐containing amorphous titanium oxide layer dispersed with nano‐sized crystallites formed prior to sparking, and a porous overlay dotted with craters formed after sparking. Ca and P were predominantly incorporated in the porous overlay, in which the amorphous region contained more Ca and P than the crystalline region regardless of the anodizing voltages. Moreover, the ratio of amorphous to crystalline regions in the porous overlay changed insignificantly with anodizing voltage. Increasing anodizing voltage enhanced the incorporation of Ca and P in the anodic film, but deteriorated the adhesion of the anodic film to the substrate. This deterioration was related to two inherent adhesive weaknesses: the aligned pores in the titanium oxide layer and the craters in the major overlay, signifying that a new anodic oxidation process that can produce high Ca‐ and P‐containing oxide film at relatively‐low anodizing voltages, i.e. ∼200 V, is a necessity. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Fibrinogen adsorption onto 316L stainless steel under polarized conditions
Authors: Gettens Robert T.T. , Gilbert Jeremy L.
Published: August 2007

Adsorption of the plasma protein fibrinogen onto electrically polarized 316L stainless steel was observed and quantified using both in situ and ex situ atomic force microscopy (AFM) techniques. Significant differences in fibrinogen adsorption were observed across voltages. Ex situ studies showed significantly lower area coverage (θ) and height of adsorbed Fb on cathodically polarized surfaces when compared to anodically polarized surfaces. Conformational differences in the protein may explain the distinctions in Fb surface area coverage (θ) and height between the anodic and cathodic cases. In situ studies showed significantly slower kinetics of Fb adsorption onto surfaces below −100 mV (vs. Ag/AgCl) compared to surfaces polarized above −100 mV. Electrochemical current density data showed large charge transfer processes (∼1 × 10−5 to 1 × 10−4 A/cm2) taking place on the 316L SS surfaces at voltages below −100 mV (vs. Ag/AgCl). These relatively large current densities point to flux of ionic species away from the surface as a major source of the reduction in adsorption kinetics rather than just hydrophilic or electrostatic effects. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Time‐dependent electrochemical characterization of the corrosion of a magnesium rare‐earth alloy in simulated body fluids
Authors: Rettig Ralf , Virtanen Sannakaisa
Published: August 2007

The electrochemistry of the corrosion process of a magnesium rare‐earth‐alloy is studied in detail in simulated body fluid (m‐SBF) over the first 5 days. The aim is to investigate the corrosion mechanism under in vitro conditions. For this purpose we also used electrolytes that contain only some of the components of SBF, they were compared to SBF to investigate the influence of the different ions in SBF. The influence of albumin on the corrosion process was studied with a solution containing m‐SBF and albumin in physiological concentration. For this study, impedance spectroscopy series measurements were performed. Additional results were gained from polarization curves. We conclude from the study that the corrosion resistance is significantly lower in m‐SBF than in simple isotonic NaCl‐solution. Albumin may form a blocking layer on the surface in the first hours of exposure. The formed corrosion layers consisting of amorphous apatite have only a low protective ability. Further results show that the corrosion processes in SBFs follow a linear time‐law. The results elucidate critical factors and mechanisms of the electrochemical corrosion process of magnesium rare‐earth alloys in SBFs, this understanding is crucial for a successful application of Mg alloys in biomedical applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Increased osteoblast adhesion on nanoparticulate calcium phosphates with higher Ca/P ratios
Authors: Ergun Celaletdin , Liu Huinan , Webster Thomas J. , Olcay Ercan , Yılmaz Şafak , Sahin Filiz C.
Published: August 2007

The biological properties of calcium phosphate‐derived materials are strongly influenced by changes in Ca/P stoichiometry and grain size, which have not yet been fully elucidated to date. For this reason, the objective of this in vitro study was to understand osteoblast (bone forming cells) adhesion on nanoparticulate calcium phosphates of various Ca/P ratios. A group of calcium phosphates with Ca/P ratios between 0.5 and 2.5 were obtained by adjusting the Ca/P stoichiometry of the initial reactants necessary for calcium phosphate precipitation. For samples with 0.5 and 0.75 Ca/P ratios, tricalcium phosphate (TCP) and Ca2P2O7 phases were observed. In contrast, for samples with 1.0 and 1.33 Ca/P ratios, the only stable phase was TCP. For samples with 1.5 Ca/P ratios, the TCP phase was dominant, however, small amounts of the hydroxyapatite (HA) phase started to appear. For samples with 1.6 Ca/P ratios, the HA phase was dominant. Last, for samples with 2.0 and 2.5 Ca/P ratios, the CaO phase started to appear in the HA phase, which was the dominant phase. Moreover, the average nanometer grain size, porosity (%), and the average pore size decreased in general with increasing Ca/P ratios. Most importantly, results demonstrated increased osteoblast adhesion on calcium phosphates with higher Ca/P ratios (up to 2.5). In this manner, this study provided evidence that Ca/P ratios should be maximized (up to 2.5) in nanoparticulate calcium phosphate formulations to increase osteoblast adhesion, a necessary step for subsequent osteoblast functions such as new bone deposition. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Different regulation of hepatocyte behaviors between natural extracellular matrices and synthetic extracellular matrices by hepatocyte growth factor
Authors: Hoshiba Takashi , Wakejima Mai , Cho Chong‐Su , Shiota Goshi , Akaike Toshihiro
Published: August 2007

The roles of growth factors and extracellular matrices (ECMs) in regulation of hepatocyte behaviors are very important for the establishment of liver‐tissue engineering. Especially, collaboration between growth factors and ECMs is a big concern for liver‐tissue engineering. In this study, the hepatocyte responses by hepatocyte growth factor (HGF) were compared between natural ECMs and a synthetic galactose‐carrying polymer: poly(N‐p‐vinylbenzyl‐4‐O‐β‐D‐galactopyranosyl‐D‐gluconamide) (PVLA). Hepatocytes underwent proliferation on type I collagen‐ and fibronectin‐coated surfaces in the presence of HGF, whereas hepatocytes formed spheroid on laminin‐1‐, PVLA‐, and poly‐L‐lysine (PLL)‐coated surfaces in the presence of HGF without the activation of proliferation. HGF accelerated ECM deposition, especially laminin‐10/11, beneath the hepatocytes cultured on PVLA‐ and PLL‐coated surfaces and the deposited laminin‐10/11 activated integrin signaling to collaborate with HGF signaling. Therefore, the deposited ECM molecules should be focused to clear the mechanism of hepatocyte behaviors in the presence of HGF. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Considering the zebrafish in a comparative context
Authors: Schilling Thomas F. , Webb Jacqueline
Published: August 2007

This article introduces a special issue on zebrafish biology that attempts to integrate developmental genetics with comparative studies of other fish species. For zebrafish researchers, comparative work offers a better understanding of the evolutionary history of their model system. Comparative biologists can gain many insights from the developmental and genetic mechanisms revealed in zebrafish that have contributed to the huge range of morphological variation among fishes that has arisen over millions of years. These ideas are considered here in various contexts, including systematics, genome organization and the development of the nervous system, pigmentation, craniofacial skeleton and dentition. Studies of the zebrafish in phylogenetic context provide an opportunity for synergy between communities using these two fundamentally different approaches. J. Exp. Zool. (Mol. Dev. Evol.) 308B:515–522, 2007. © 2007 Wiley‐Liss, Inc.
Replication‐competent, oncolytic herpes simplex virus type 1 mutants induce a bystander effect following ganciclovir treatment
Authors: Luo Chenhong , Mori Isamu , Goshima Fumi , Ushijima Yoko , Nawa Akihiro , Kimura Hiroshi , Nishiyama Yukihiro
Published: August 2007

Cells expressing herpes simplex virus (HSV) thymidine kinase (tk) are killed by ganciclovir (GCV). Adjacent cells without HSV‐tk also die, a phenomenon known as the ‘bystander effect’. However, there is no evidence that replication‐competent HSV induces a bystander effect in the presence of GCV. Therefore, we investigated the bystander effect in HEp‐2 cells infected with replication‐competent, oncolytic HSV‐1 mutants, hrR3 and HF10. In cells infected at a multiplicity of infection (MOI) of 3, GCV did not induce apoptosis. At low MOIs of 0.3 and 0.03, however, a number of adjacent, uninfected cells apoptosed following GCV treatment. Irrespective of GCV treatment, HEp‐2 cells expressed minimal levels of connexin 43 (Cx43). However, Cx43 expression was enhanced by GCV in response to infection with HF10 at an MOI of 0.3, but not at an MOI of 3. Expression of other proteins involved in gap junctions, including Cx26 and Cx40, was not augmented under these conditions. The PKA and PI3K signal transduction pathways are likely involved in enhanced Cx43 expression as inhibitors of these pathways prevented Cx43 upregulation. These results suggest that infection with replication‐competent HSV‐1 induces the bystander effect in cells treated with GCV because of efficient intercellular transport of active GCV through abundant gap junctions. Copyright © 2007 John Wiley & Sons, Ltd.
On graphs with subgraphs having large independence numbers
Authors: Alon Noga , Sudakov Benny
Published: August 2007

Let G be a graph on n vertices in which every induced subgraph on ${s}={\log}^{3}\, {n}$ vertices has an independent set of size at least ${t}={\log}\, {n}$. What is the largest ${q}={q}{(n)}$ so that every such G must contain an independent set of size at least q? This is one of the several related questions raised by Erdős and Hajnal. We show that ${q}{(n)}= \Theta({\log}^{2} {n}/{\log}\, {\log} \,{n})$, investigate the more general problem obtained by changing the parameters s and t, and discuss the connection to a related Ramsey‐type problem. © 2007 Wiley Periodicals, Inc. J Graph Theory 56: 149–157, 2007
Quantitative analysis with modern bioanalytical mass spectrometry and stable isotope labeling
Authors: Richards Dawn P. , Sojo Luis E. , Keller Bernd O.
Published: August 2007

The invention of new ionization techniques namely electrospray ionization and matrix‐assisted laser desorption/ionization combined with the development of novel mass spectrometer analyzers and evolving isotope‐ratio mass spectrometry have fueled the presence and use of modern mass spectrometric methodologies in many bioanalytical laboratories. Consequently, over the past two decades, a steadily increasing number of quantitative methods employing stable isotope labeling techniques have been reported, including prominent examples of methods to determine differential expression of proteins in disease studies, new‐born screening for metabolic disorders, and tracing drugs or dietary compounds and their respective metabolites. Labeling biomolecules for quantitative studies using mass spectrometry has several challenges, including potentially insufficient labeling efficiency, ionization suppression, chromatographic separation of labeled and non‐labeled compounds, and isotope exchange with the environment. It is not surprising that method development to minimize or eliminate existing limitations represents a very active and dynamic research area. Copyright © 2007 John Wiley & Sons, Ltd.
Small‐fiber involvement in spinobulbar muscular atrophy (Kennedy's disease)
Authors: Manganelli Fiore , Iodice Valeria , Provitera Vincenzo , Pisciotta Chiara , Nolano Maria , Perretti Anna , Santoro Lucio
Published: August 2007

We assessed the involvement of cutaneous innervation in two subjects with a molecularly confirmed diagnosis of spinobulbar muscular atrophy (SBMA) using antidromic nerve conduction studies, quantitative sensory testing, and sweat tests, as well as immunohistochemical techniques and confocal microscopy of glabrous and hairy skin biopsy. Both patients showed a marked reduction in amplitude of sensory action potentials and moderate or severe abnormalities of tactile thresholds and mechanical pain perception. A severe reduction of sweat drops on the Silastic imprint test and a widespread loss of small myelinated and unmyelinated fibers in hairy skin were also observed. Fiber loss involved either somatic or autonomic fibers and did not show any distal–proximal gradient. These results, together with loss of Meissner corpuscles and their large myelinated afferent fibers in glabrous skin, confirmed the extensive involvement of sensory neurons of large and small size and revealed an autonomic skin denervation in SBMA. Muscle Nerve, 2007
Random porosity fields and their influence on the stability of granular media
Authors: Andrade José E. , Baker Jack W. , Ellison Kirk C.
Published: August 2007

It is well established that the mechanical behavior of granular media is strongly influenced by the media's microstructure. In this work, the influence of the microstructure is studied by integrating advances in the areas of geostatistics and computational plasticity, by spatially varying the porosity on samples of sand. In particular, geostatistical tools are used to characterize and simulate random porosity fields that are then fed into a nonlinear finite element model. The underlying effective mechanical response of the granular medium is governed by a newly developed elastoplastic model for sands, which readily incorporates spatial variability in the porosity field at the meso‐scale. The objective of this study is to assess the influence of heterogeneities in the porosity field on the stability of sand samples. One hundred and fifty isotropic and anisotropic samples of dense sand are failed under plane‐strain compression tests using Monte Carlo techniques. Results from parametric studies indicate that the axial strength of a specimen is affected by both the degree and orientation of anisotropy in heterogeneous porosity values with anisotropy orientation having a dominant effect, especially when the bands of high porosity are aligned with the natural orientation of shear banding in the specimen. Copyright © 2007 John Wiley & Sons, Ltd.
Multivariate chromatographic fingerprint preparation and authentication of plant material from the genus Bauhinia
Authors: Soares Patricia Kaori , Scarminio Ieda Spacino
Published: August 2007

Multivariate analysis and statistical mixture designs were used for chromatographic fingerprint preparation and authentication of the plant material of three species of the genus Bauhinia. The extracts were analysed by reversed‐phase high‐performance liquid chromatography. Mixture design gave an optimum solvent composition for extracting components from the plants of 36% dichloromethane, 17% ethanol and 47% ethyl acetate (by volume), while an optimum mobile phase for chromatographic analyses was found to be 27% methanol, 27% acetonitrile and 46% of water (by volume). Results from principal component analysis, hierarchical analysis and soft independent modelling by class analogy showed that Bauhinia candicans cannot be synonymous with B. forficata Link. It was also possible to trace the metabolic profile without identifying its chemical constituents and to determine a chromatographic discriminating region. The characteristics responsible for discrimination between B. candicans and B. forficata were more polar substances that presented peaks with retention times around 1.65 and 1.81 min. Copyright © 2007 John Wiley & Sons, Ltd.
The role of impurities in thermally stimulated luminescence of MgO:Mn2+ and MgO:V2+ crystals irradiated in a reactor
Authors: Kvatchadze V. , Dekanozishvili G. , Galustashvili M. , Kalabegishvili T. , Keratishvili N. , Zardiashvili D.
Published: August 2007

The high‐temperature thermally stimulated luminescence (TSL) of nominally pure MgO crystals and MgO crystals with excessive amounts of paramagnetic manganese and vanadium ions irradiated in a reactor has been studied. It was observed that the influence of impurity on the TSL of crystal is different at low and relatively high doses. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ultrasonic properties of glassy alloys in terms of complex wave elasticity
Authors: Fukuhara Mikio , Zhang Wei , Inoue Akihisa
Published: August 2007

Using ultrasonics, acoustic characteristics of Pd40Cu30P20, Zr55Cu30Al10Ni5, Zr65Pd12.5Ni10Al7.5Cu5, Cu55Zr30Ti10Pd5, Cu45Zr20Hf25Ag10 and Ti41.5Cu42.5Ni7.5Hf5Zr2.5Sn1 glassy alloys were examined in terms of complex elasticity. The order of bulk modulus (K), Lamé parameter (λ), Young (E) and shear (G) moduli of the glassy alloys shows the monopolistical character of the glassy alloys, except for polymers and rubbers. Poison's ratio correlates well to the anisotropy factor and the ratio G /K, accompanied by dilational and shear attenuation coefficients, showing characteristic one‐dimensional elastic deformability of the glassy alloys. The complex elasticity shows that the viscoelasticity of the glassy alloys is predominated by volumetric motion, associated with the complex waves. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Refractive index, static dielectric constant, energy band gap and oscillator parameters of Ga2SeS single crystals
Authors: Qasrawi A. F. , Gasanly N. M.
Published: August 2007

The optical properties of Bridgman method grown Ga2SeS crystals have been investigated by means of room‐temperature transmittance and reflectance spectral analysis. The optical data have revealed direct and indirect allowed transition band gaps of 2.49 and 2.10 eV, respectively. The room‐temperature refractive index, which was calculated from the reflectance and transmittance data, allowed the identification of the dispersion and oscillator energies, static dielectric constant and static refractive index as 20.93 eV and 4.01 eV, 6.21 and 2.49, respectively. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of one‐dimensional “trenched” GaN nanowires and their interconnections
Authors: Lebedev V. , Cengher D. , Fischer M. , Tonisch K. , Cimalla V. , Niebelschütz M. , Ambacher O.
Published: August 2007

In this work, a new approach of nanowire fabrication utilizing selective growth of planar GaN wires embedded into the insulating matrix is reported. The selective growth has been released by means of a Six Ny mask and a metal‐organic chemical vapour deposition. The main advantage of the investigated fabrication process is a planar geometry of the wires allowing the use of conventional interconnection techniques such as optical lithography. Design, fabrication technology and interconnection geometry of some early examples are discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Positron annihilation at grain boundaries in metals
Authors: Kuriplach J. , Melikhova O. , Hou M. , Van Petegem S. , Zhurkin E. , Šob M.
Published: August 2007

Positron annihilation at selected tilt and twist grain boundaries in iron and nickel is examined theoretically. First the atomic structure of studied perfect and imperfect grain boundaries is obtained using molecular dynamics simulations. Characteristics of positrons trapped at such GBs are then calculated employing the atomic superposition method and are related to free volumes found at GBs. It is observed that in some cases vacancies introduced into ideal grain boundaries do not result in an increase of the positron lifetime. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Approaches to evaluation of treatment effect in randomized clinical trials with genomic subset
Authors: Wang Sue‐Jane , O'Neill Robert T. , Hung H. M. James
Published: August 2007

With the advances in human genomic/genetic studies, the clinical trial community gradually recognizes that phenotypically homogeneous patients may be heterogeneous at the genomic level. The genomic technology brings a possible avenue for developing a genomic (composite) biomarker to predict a genomically responsive patient subset that may have a (much) higher likelihood of benefiting from a treatment.

Randomized controlled trial is the mainstay to provide scientifically convincing evidence of a purported effect a new treatment may demonstrate. In conventional clinical trials, the primary clinical hypothesis pertains to the therapeutic effect in all patients who are eligible for the study defined by the primary efficacy endpoint. The aspect of one‐size‐fits‐all surrounding the conventional design has been challenged, particularly when the diseases may be heterogeneous due to observable clinical characteristics and/or unobservable underlying the genomic characteristics.

Extension from the conventional single population design objective to an objective that encompasses two possible patient populations will allow more informative evaluation in the patients having different degrees of responsiveness to medication. Building in conventional clinical trials, an additional genomic objective can generate an appealing conceptual framework from the patient's perspective in addressing personalized medicine in well‐controlled clinical trials. There are many perceived benefits of personalized medicine that are based on the notion of being genomically proactive in the identification of disease and prevention of disease or recurrence. In this paper, we show that an adaptive design approach can be constructed to study a clinical hypothesis of overall treatment effect and a hypothesis of treatment effect in a genomic subset more efficiently than the conventional non‐adaptive approach. Published in 2007 by John Wiley & Sons, Ltd.
Odd electrons in molecular chemistry, surface science, and solid state magnetism
Authors: Sheka E. F.
Published: August 2007

A unified theoretical or computational odd‐electrons approach is suggested to nanomaterials, making possible their consideration on the same conceptual basis as well as on the same computational footing. The current paper presents the approach application to the chemistry of fullerenes, carbon single‐walled nanotubes, surface science of silicon crystal, as well as to the molecular magnetism of both molecular crystals composed of transitional metal complexes and solid polymerized fullerenes. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Catching Remote Administration Trojans (RATs)
Authors: Chen Zhongqiang , Wei Peter , Delis Alex
Published: August 2007

A Remote Administration Trojan (RAT) allows an attacker to remotely control a computing system and typically consists of a server invisibly running and listening to specificTCP/UDPports on a victim machine as well as a client acting as the interface between the server and the attacker. The accuracy of host and/or network‐based methods often employed to identifyRATshighly depends on the quality of Trojan signatures derived from static patterns appearing inRATprograms and/or their communications. Attackers may also obfuscate such patterns by havingRATsuse dynamic ports, encrypted messages, and even changing Trojan banners. In this paper, we propose a comprehensive framework termedRAT Catcher, which reliably detects and ultimately blocksRATmalicious activities even when Trojans use multiple evasion techniques. Employing network‐based methods and functioning ininlinemode to inspect passing packets in real time, ourRAT Catchercollects and maintains status information for every connection and conducts session correlation to greatly improve detection accuracy. TheRAT Catcherre‐assembles packets in each data stream and dissects the resulting aggregation according to known Trojan communication protocols, further enhancing its traffic classification. By scanning not only protocol headers but also payloads,RAT Catcheris a truly application‐layer inspector that performs a range of corrective actions on identified traffic including alerting, packet dropping, and connection termination. We show the effectiveness and efficiency ofRAT Catcherwith experimentation in both laboratory and real‐world settings. Copyright © 2007 John Wiley & Sons, Ltd.
Changes in the structure and heterogeneity of vegetation and microsite environments with the chronosequence of primary succession on a glacier foreland in Ellesmere Island, high arctic Canada
Authors: Mori Akira S. , Osono Takashi , Uchida Masaki , Kanda Hiroshi
Published: August 2007

Primary plant succession was investigated on a well‐vegetated glacier foreland on Ellesmere Island in high arctic Canada. A field survey was carried out on four glacier moraines differing in time after deglaciation to assess vegetation development and microsite modification in the chronosequence of succession. The results showed evidence of directional succession without species replacement, which is atypical in the high arctic, reflecting the exceptionally long time vegetation development. During this successional process, Salix arctica dominated throughout all moraines. The population structures of S. arctica on these moraines implied the population growth of this species with progressing succession. The population density of S. arctica reflected the abundance of vascular plants, suggesting that development of the plant community might be related to structural changes and the growth of constituting populations. Through such growths of the population and the whole community with progressing succession, the spatial heterogeneity of vegetation gradually declines. Moreover, this vegetation homogenization is accompanied by changes in the spatial heterogeneity of microsite environments, suggesting significant plant effects on the modification of microsite environments. Accordingly, it was concluded that the directional primary succession observed on this glacier foreland is characterized by the initial sporadic colonization of plants, subsequent population growths, and the community assembly of vascular plants, accompanied by microsite modification.
Boron and Nitrogen Doped Single walled Carbon Nanotubes as Possible Dilute Magnetic Semiconductors
Authors: Owens Frank J
Published: August 2007

The structure of single walled armchair and zig-zag carbon nanotubes having 70 atoms and two carbons replaced by boron or nitrogen is obtained at minium energy using HF/6-31G* molecular orbital theory. The calculations show that the ground state of the zig-zag tubes is a triplet state while for the armchair tubes it is a singlet. In the zig-zag tubes the density of states at the Fermi level is greater for the spin down states compared to the spin up state indicating that the doped tubes could be ferromagnetic.
ON THE FAMILY OF DIOPHANTINE TRIPLES {k− 1,k+ 1, 16k3− 4k}
Authors: BUGEAUD YANN , DUJELLA ANDREJ , MIGNOTTE MAURICE
Published: August 2007

It is proven that ifk≥ 2 is an integer anddis a positive integer such that the product of any two distinct elements of the setincreased by 1 is a perfect square, thend= 4kord= 64k5−48k3+8k. Together with a recent result of Fujita, this shows that all Diophantine quadruples of the form {k− 1,k+ 1,c,d} are regular.
EXISTENCE OF A SOLUTION FOR A SINGULAR DIFFERENTIAL EQUATION WITH NONLINEAR FUNCTIONAL BOUNDARY CONDITIONS
Authors: CABADA ALBERTO , CID JOSÉ ÁNGEL
Published: August 2007

In this paper we deal with some boundary value problems related with diffusion processes in the presence of lower and upper solutions. Singularities as well as non local boundary conditions are allowed. We also prove the existence of extremal solutions and the uniqueness of solution for a particular case.
BANACH SPACES WITH SEPARABLE DUALS SUPPORT DUAL HYPERCYCLIC OPERATORS
Authors: SALAS HÉCTOR N.
Published: August 2007

Let E be a Banach space such that its dual E* is separable. We show that there exists a hypercyclic bounded operator T on E such that its adjoint T* is also hypercyclic on E*. We also exhibit a new kind of dual hypercyclic operator. Thus answers affirmatively two of the questions raised by Henrik Petersson in a recent paper.
A NOTE ON SIMULTANEOUS AND MULTIPLICATIVE DIOPHANTINE APPROXIMATION ON PLANAR CURVES
Authors: BADZIAHIN DZMITRY , LEVESLEY JASON
Published: August 2007

Let $\mathbb C$ be a non-degenerate planar curve. We show that the curve is of Khintchine-type for convergence in the case of simultaneous approximation in $\mathbb R^2$ with two independent approximation functions; that is if a certain sum converges then the set of all points (x,y) on the curve which satisfy simultaneously the inequalities ||qx|| < ψ1(q) and ||qy|| < ψ2(q) infinitely often has induced measure 0. This completes the metric theory for the Lebesgue case. Further, for multiplicative approximation ||qx|| ||qy|| < ψ(q) we establish a Hausdorff measure convergence result for the same class of curves, the first such result for a general class of manifolds in this particular setup.
ON THE CENTRALIZER OF AN ELEMENT OF ORDER FOUR IN A LOCALLY FINITE GROUP
Authors: SHUMYATSKY PAVEL
Published: August 2007

We prove that if G is a locally finite group admitting an automorphism φ of order four such that CG(φ) is Chernikov, then G has a soluble subgroup of finite index.