bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Annealing on the 1.5 μm Light Emission of Er-doped ZnO Thin Films and its Crystal Quality
Authors: Ishikawa Yukari , Okamoto Mitsuhiro , Tanaka Shigeru , Nezaki Dai , Shibata N.
Published: October 2005

Intensity variation of 1.5 μm light emission at room temperature from Er-doped epitaxial and polycrystal ZnO films depending on annealing temperature (773–1373 K) was studied. As-grown Er-doped epitaxial ZnO film emitted 1.5 μm photoluminescence(PL) higher than as-grown Er-doped polycrystal ZnO. It was found that the annealing in air increases PL intensity and the maximum PL intensity was obtained by annealing at optimal temperature (1073 K). Spectrum shape and intensity of 1.5 μm PL of Er-doped epitaxial ZnO after annealing at 1073 K resembled those of Er-doped polycrystal ZnO after annealing at 1073 K. X-ray diffraction measurement demonstrated that annealing improves crystal quality of Er-doped ZnO film. We assumed that the process of 1.5 μm light emission is dependent on local area placement of Zn and O atoms around Er as well as crystal quality of ZnO.
Interpreting social science link analysis research: A theoretical framework
Authors: Thelwall Mike
Published: October 2005

Link analysis in various forms is now an established technique in many different subjects, reflecting the perceived importance of links and of the Web. A critical but very difficult issue is how to interpret the results of social science link analyses. It is argued that the dynamic nature of the Web, its lack of quality control, and the online proliferation of copying and imitation mean that methodologies operating within a highly positivist, quantitative framework are ineffective. Conversely, the sheer variety of the Web makes application of qualitative methodologies and pure reason very problematic to large‐scale studies. Methodology triangulation is consequently advocated, in combination with a warning that the Web is incapable of giving definitive answers to large‐scale link analysis research questions concerning social factors underlying link creation. Finally, it is claimed that although theoretical frameworks are appropriate for guiding research, a Theory of Link Analysis is not possible.
Solid‐supported and pegylated H–Pro–Pro–Asp–NHR as catalysts for asymmetric aldol reactions
Authors: Revell Jefferson D. , Gantenbein Daniel , Krattiger Philipp , Wennemers Helma
Published: October 2005

H–Pro–Pro–Asp–NH2 is a highly active and selective catalyst for asymmetric aldol reactions. Here, the versatility of H–Pro–Pro–Asp–NH2 has been further improved by immobilization on a solid support and functionalization with a short polyethylene glycol linker at the C‐terminus. The development, synthesis, and the catalytic properties in aldol reactions of H–Pro–Pro–Asp–resin and H–Pro–Pro–Asp–Ahx–NH(CH2CH2O)3CH3 are described. For the solid‐supported catalyst, TentaGel with a loading of 0.1–0.2 mmol g–1 proved to be the optimal support. The solid‐supported catalyst can be recycled at least three times without a significant drop in the catalytic activity or selectivity. Using the pegylated catalyst H–Pro–Pro–Asp–Ahx–NH(CH2CH2O)3CH3, only 0.5 mol % are necessary to obtain aldol products in up to 96% yield and 91% enantiomeric excess. In all cases, enantioselectivities are comparable to those obtained with the parent catalyst H–Pro–Pro–Asp–NH2. Thus, immobilization of H–Pro–Pro–Asp–NH2 on Tentagel as well as pegylation led to catalysts with selectivities comparable to the nonmodified catalyst, exhibiting additional distinct advantages such as facile reusability, ease of handling, higher solubility, and thereby greater versatility. handling, higher solubility, and thereby greater versatility. © 2005 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 84: 105–113, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Structure optimization in a three‐dimensional off‐lattice protein model
Authors: Huang Wenqi , Liu Jingfa
Published: October 2005

We studied a three‐dimensional off‐lattice AB model with two species of monomers, hydrophobic (A) and hydrophilic (B), and present two optimization algorithms: face‐centered‐cubic (FCC)‐lattice pruned‐enriched‐Rosenbluth method (PERM) and subsequent conjugate gradient (PERM++) minimization and heuristic conjugate gradient (HCG) simulation based on “off‐trap” strategy. In PERM++, we apply the PERM to the FCC‐lattice to produce the initial conformation, and conjugate gradient minimization is then used to reach the minimum energy state. Both algorithms have been tested in the three‐dimensional AB model for all sequences with lengths 13 ≤ n ≤ 55. The numerical results show that the proposed methods are very promising for finding the ground states of proteins. In several cases, we renew the putative ground states energy values. © 2005 Wiley Periodicals, Inc. Biopolymers 82: 93–98, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Simple and versatile restraints for the accurate modeling of α‐helical coiled‐coil structures of multiple strandedness, orientation and composition
Authors: Charest Gabriel , Lavigne Pierre
Published: October 2005

We present a minimalist approach for the modeling of the three‐dimensional structure of multistranded α‐helical coiled coils. The approach is based on empirical principles introduced by F. H. C. Crick (F. H. C. Crick, Acta Crystallogr, 1953, Vol. 6, pp. 689–697). Crick hypothesized that keeping the distance between the residues at the interacting interface of α‐helices constant would lead to supercoiling or the formation of a coiled coil through the knobs‐into‐holes mode of packing. We have implemented the latter hypothesis in a simulating annealing protocol in the simple form of interhelical distance restraints (two per heptad) between Cα at the interfacial positions a and d. To demonstrate the authenticity of Crick's hypothesis and the precision and accuracy of our approach, we have modeled the crystal structures of six synthetic coiled coils in dimeric, trimeric, and tetrameric states. The mean root mean square deviations (RMSDs) between the backbone atoms of the ensemble of structures calculated and those of the corresponding geometric averages is always below 0.76 Å, indicating that our protocol has an excellent degree of convergence and precision. The RMSDs between the backbone atoms of each of the six geometric average structures and the backbone of the corresponding crystal structures all range between 0.43 and 0.95 Å, indicative of excellent accuracy and proving the authenticity of Crick's hypothesis. Moreover, without specifying any dihedral angles, we found that in 81% of the occurrences, the most populated conformer of the side chains at positions a and d in the ensembles calculated were identical to those observed in the crystal structures. This shows that our simple approach, which is the simplest reported so far, can generate accurate results for the backbone and side chains. Finally, as a test case for a wider application of our approach in the field of structural proteomics, we describe the successful modeling of the overall structure of SNARE and the organization of its interfacial ionic layer known to play an important functional role. © 2005 Wiley Periodicals, Inc. Biopolymers 81: 202–214, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Scavenging of reactive oxygen species by some nonsteroidal anti‐inflammatory drugs and fenofibrate
Authors: Kładna Aleksandra , Aboul‐Enein Hassan Y. , Kruk Irena , Lichszteld Krzysztof , Michalska Teresa
Published: October 2005

Ketoprofen and tolmetin are widely used nonsteroidal anti‐inflammatory drugs, whereas fenofibrate belongs to a family of hypolipidemic drugs used in the prevention of cardiovascular diseases. The aim of this study was to assess effect of these drugs on reactions generating reactive oxygen species (ROS). The following generators of ROS were used: 18‐crown‐6/KO2 dissolved in DMSO as a source of superoxide radical (
$O^{\overline{\bullet}}_2$), the Fenton‐like reaction (Cu/H2O2) for hydroxyl radical (HO•), 2,2′‐azobis (2‐amidino‐propane) dichloride (AAPH) as peroxyl radical (ROO•) generator, and a mixture of alkaline aqueous H2O2 and acetonitrile for singlet oxygen (1O2). Measurements were done using chemiluminescence, fluorescence, and spin‐trapping with 2,2,6,6‐tetramethylpiperidine combined with electron spin resonance spectroscopy (ESR), and a deoxyribose assay based on the spectrophotometry. The results obtained demonstrated that all tested drugs were active against $O^{\overline{\bullet}}_2$. There was a clear ranking of drug inhibition effects on chemiluminescence from the $O^{\overline{\bullet}}_2$
system: ketoprofen > tolmetin > fenofibrate. The examined compounds inhibited the HO•‐dependent deoxyribose degradation and scavenged the ROO• concentration dependently with an order of potencies similar to that of the superoxide radical system. Hence, these results indicate that the studied drugs show broad ROS scavenging property and, as a consequence, might decrease tissue damage due to the ROS and thus to contribute to anti‐inflammatory therapy. © 2005 Wiley Periodicals, Inc. Biopolymers 82: 99–105, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Bioleaching of sulfidic tailing samples with a novel, vacuum‐positive pressure driven bioreactor
Authors: Rzhepishevska Olena I. , Lindström E. Börje , Tuovinen Olli H. , Dopson Mark
Published: October 2005

This study presents a design for a novel bioreactor that uses alternating vacuum and positive pressure cycles to transfer acidic leach solution in and out of contact with finely ground sulfidic mine tailings. These tailings constitute an environmental problem that needs experimental data to support the development of management and control strategies. A conventional stirred tank bioreactor was used as a reference system. Both bioreactors were inoculated with mixed cultures of acidophilic iron and sulfur oxidizers. The rate of the bioleaching of tailings was 0.50 ± 0.14 g Fe/L · day in the stirred tank bioreactor and 0.17 ± 0.05 g Fe/L · day in the novel bioreactor. Microbial populations were identified in the two‐bioreactor systems by analysis of 16S rRNA genes involving amplification, denaturing gradient gel electrophoresis (DGGE), cloning, and sequencing. The inoculum contained sulfur‐oxidizing Acidithiobacillus caldus and Acidithiobacillus thiooxidans, iron oxidizers from the genera Leptospirillum and Ferroplasma, and a chemoorganotrophic Alicyclobacillus sp. During bioleaching of the tailings, the microbial populations in both bioreactors were similar to the inoculum culture, except that At. thiooxidans outgrew At. caldus. Sequences consistent with a Sulfobacillus sp. were amplified from both bioreactor samples although this bacterium was initially below the level of detection in the inoculum. After prolonged operation, Ferroplasma acidiphilum and an uncultured bacterium related to the CFB group were also detected in the novel bioreactor, whereas Sulfobacillus sp. was no longer detected. The novel bioreactor has potential uses in other areas of environmental biotechnology that involves periodic contact of liquids with solid substrates. © 2005 Wiley Periodicals, inc.
Engineering of osteoinductive grafts by isolation and expansion of ovine bone marrow stromal cells directly on 3D ceramic scaffolds
Authors: Scaglione S. , Braccini A. , Wendt D. , Jaquiery C. , Beltrame F. , Quarto R. , Martin Ivan
Published: October 2005

In this work, we investigated whether osteoinductive constructs can be generated by isolation and expansion of sheep bone marrow stromal cells (BMSC) directly within three‐dimensional (3D) ceramic scaffolds, bypassing the typical phase of monolayer (2D) expansion prior to scaffold loading. Nucleated cells from sheep bone marrow aspirate were seeded into 3D ceramic scaffolds either by static loading or under perfusion flow and maintained in culture for up to 14 days. The resulting constructs were exposed to enzymatic treatment to assess the number and lineage of extracted cells, or implanted subcutaneously in nude mice to test their capacity to induce bone formation. As a control, BMSC expanded in monolayer for 14 days were also seeded into the scaffolds and implanted. BMSC could be isolated and expanded directly in the 3D ceramic scaffolds, although they proliferated slower than in 2D. Upon ectopic implantation, the resulting constructs formed a higher amount of bone tissue than constructs loaded with the same number of 2D‐expanded cells. Constructs cultivated for 14 days generated significantly more bone tissue than those cultured for 3 days. No differences in bone formation were found between samples seeded by static loading or under perfusion. In conclusion, the culture of bone marrow nucleated cells directly on 3D ceramic scaffolds represents a promising approach to expand BMSC and streamline the engineering of osteoinductive grafts. © 2005 Wiley Periodicals, inc.
Detection of prostate carcinoma with contrast‐enhanced sonography using intermittent harmonic imaging
Authors: Halpern Ethan J. , Ramey John R. , Strup Stephen E. , Frauscher Ferdinand , McCue Peter , Gomella Leonard G.
Published: October 2005

BACKGROUND

The purpose of this study was to assess prostate carcinoma detection and discrimination of benign from malignant prostate tissue with contrast‐enhanced ultrasonography.

METHODS

In all, 301 subjects referred for prostate biopsy were evaluated with contrast‐enhanced sonography using continuous harmonic imaging (CHI) and intermittent harmonic imaging (IHI) with interscan delay times of 0.2, 0.5, 1.0, 2.0 seconds, as well as continuous color and power Doppler. Targeted biopsy cores were obtained from sites of greatest enhancement, followed by spatially distributed cores in a modified sextant distribution.

RESULTS

Carcinoma was detected in 363 biopsy cores from 104 of 301 subjects (35%). Carcinoma was found in 15.5% (175 of 1133) of targeted cores and 10.4% (188 of 1806) of sextant cores (P < 0.01). Among subjects with carcinoma, targeted cores were twice as likely to be positive (odds ratio [OR] = 2.0, P < 0.001). Clustered receiver operating characteristic (ROC) analysis of imaging findings at sextant biopsy sites yielded the following Az values: precontrast gray scale: 0.58; precontrast color Doppler: 0.53; precontrast power Doppler: 0.58; CHI: 0.62; IHI (0.2 sec): 0.64; IHI (0.5 sec): 0.63; IHI (1.0 sec): 0.65; IHI (2.0 sec): 0.61; contrast‐enhanced color Doppler: 0.60; contrast‐enhanced power Doppler: 0.62. A statistically significant benefit was found for IHI over baseline imaging (P < 0.05).

CONCLUSIONS

The carcinoma detection rate of contrast‐enhanced targeted cores is significantly higher when compared with sextant cores. Contrast‐enhanced transrectal sonography with IHI provides a statistically significant improvement in discrimination between benign and malignant biopsy sites. However, given the relatively low ROC areas, this technique may not be sufficient to predict which patients have benign versus malignant disease. Cancer 2005. © 2005 American Cancer Society.
Targeted agents for the treatment of advanced renal cell carcinoma
Authors: Stadler Walter M.
Published: October 2005

Metastatic renal cell carcinoma (RCC) is currently one of the most treatment‐resistant malignancies. However, the elucidation of the molecular mechanisms underlying RCC development has led to the identification of promising targets for novel therapeutic agents. The involvement of the Von Hippel–Lindau protein pathway in clear cell RCC suggests that downstream targets of this pathway, namely, signaling through vascular endothelial growth factor (VEGF) in endothelial cells, platelet‐derived growth factor (PDGF) in endothelial cells and pericytes, and the epidermal growth factor receptor (EGFR) pathway in tumor cells are all reasonable and rational therapeutic targets. A number of agents are in development that target VEGF (bevacizumab, a recombinant, humanized monoclonal antibody) or its receptor, VEGFR (PTK787, SU011248, and BAY 43‐9006, all of which are small molecule inhibitors). Agents targeting EGFR also are being investigated clinically (gefitinib, cetuximab, erlotinib, and ABX‐EGF). The Raf/MEK/ERK pathway is an important downstream convergence point for signaling through VEGFR, platelet‐derived growth factor receptor (PDGFR), and EGFR (all have receptor tyrosine kinase activity) and also has important antiapoptotic effects, thereby providing an attractive target for intervention. In addition to inhibiting VEGFR and PDGFR‐mediated angiogenic pathways, BAY 43‐9006 has been shown to inhibit the Raf/MEK/ERK pathway at the level of Raf kinase. MEK‐directed therapeutic approaches are also in development. Given that multiple molecular pathways are implicated in tumor cell growth, antitumor activity may be increased by using individual agents that target multiple pathways, or by combining different agents to allow vertical or horizontal inhibition of relevant pathways. Cancer 2005. © 2005 American Cancer Society.
Extrapulmonary tuberculosis active infection misdiagnosed as cancer
Authors: Aisenberg Gabriel M. , Jacobson Kalen , Chemaly Roy F. , Rolston Kenneth V. , Raad Isaam I. , Safdar Amar
Published: October 2005

BACKGROUND

Extrapulmonary tuberculosis is an uncommon disease in the U.S., even in immunosuppressed cancer patients. This study evaluated characteristics and frequency of extrapulmonary tuberculosis in patients at a tertiary care referral cancer center.

METHODS

The records of all consecutive patients with Mycobacterium tuberculosis diagnosed during January 2001 through April 2005 at the M. D. Anderson Cancer Center were reviewed after obtaining institutional review board approval.

RESULTS

There were 26 patients with active tuberculosis during the period studied; 18 of them were cancer patients and the others had been referred for a presumed cancer but did not have cancer. The overall rate of active tuberculosis during this period was 0.2 in 1000 new cancer diagnoses. There were 18 men (69%), the median age was 54 years (range, 3–84 yrs), and 16 patients (62%) were born in the U.S. Thirteen (72%) of the 18 cancer patients had solid‐organ tumors; 3 of the 5 patients with a hematologic malignancy had non‐Hodgkin lymphoma. Three patients (12%) had diabetes mellitus, and 2 patients (8%) had received high‐dose (>1 mg/kg of prednisone daily) corticosteroids in the previous week. No patient had a recent history (within the past 4 wks) of chemotherapy; 4 patients had neutropenia. Cough was a prominent symptom (31%), followed by bone pain (19%), dyspnea (15%), and fever (12%). Fifteen patients (58%) had extrapulmonary infection, including 5 patients with concurrent pulmonary involvement; 7 noncancer patients (88%) and 8 cancer patients (44%, P = 0.22) had extrapulmonary disease. In 11 patients (42%), the lungs were the only site of active tuberculosis. Cavitary pneumonia was seen radiographically in 3 of 16 patients (19%) with pulmonary tuberculosis. All M. tuberculosis isolates were susceptible to isoniazid, rifampin, ethambutol, and pyrazinamide; streptomycin resistance was noted in 1 of 22 (5%) isolates tested. Twenty‐two patients (85%) received appropriate antituberculosis treatment; all had a clinical and radiographic response. In 3 patients (12%) the cause of death was attributed to M. tuberculosis disease; 2 of 18 cancer patients (11%) died of progressive M. tuberculosis, and they had advanced solid‐organ cancer, whereas 1 of 8 patients (13%) without cancer died and the tuberculosis diagnosis was made only on postmortem examination. Univariate analysis showed no significant differences in patients or disease characteristics between non–U.S.‐born and U.S.‐born patients, whereas noncancer patients (age 52 yrs) and those with extrapulmonary tuberculosis (age 53 yrs) were younger compared with cancer patients (63 yrs; P < 0.007) and those with pulmonary disease (age 60 yrs; P = 0.09).

CONCLUSIONS

Extrapulmonary tuberculosis was relatively common in younger patients with active M. tuberculosis infection, and was often initially misdiagnosed as cancer. Cancer 2005. © 2005 American Cancer Society.
Characteristics of initiation and early events for muscle development in the Xenopus limb bud
Authors: Satoh Akira , Sakamaki Kazuhiro , Ide Hiroyuki , Tamura Koji
Published: October 2005

In Xenopus laevis, limb buds start to develop at a later point of the larval stage, prior to metamorphosis. This onset of limb development in Xenopus is totally different from that in amniotes such as birds and mammals, in which limb buds emerge at an early stage of embryogenesis, in parallel with other organogenesis. We investigated limb myogenesis in Xenopus, focusing on myogenic gene expression, myogenic ability of limb bud cells in the early stage, and the origin of myogenic precursor cells in the limb bud. The Xenopus early limb bud contains myoD/cardiac actin‐positive and pax3/pax7‐negative cells. Interestingly, results of transplantation experiments have revealed that this early limb bud contains myogenic precursor cells. In order to know the contribution of myogenic cells in somites to myogenic precursor cells in the early limb bud, we used a Cre‐LoxP system for tracing over a long period. The results of fate tracing for myogenic cells in somites of the Xenopus embryo suggested that early‐specified myogenic cells in somites do not contribute to limb muscle in Xenopus. Taken together, the results suggest that limb muscle development in Xenopus has characteristics of initiation and early events distinct from those of other vertebrate clades. Developmental Dynamics 234:846–857, 2005. © 2005 Wiley‐Liss, Inc.
An in vitro model for characterizing the post‐migratory cranial neural crest cells of the first branchial arch
Authors: Zhao Hu , Bringas Pablo , Chai Yang
Published: October 2005

The cranial neural crest (CNC) is a transient cell population that originates at the crest of the neural fold and gives rise to multiple cell types during craniofacial development. Traditionally, researchers have used tissue explants, such as the neural tube, to obtain primary neural crest cells for their studies. However, this approach has inevitably resulted in simultaneous isolation of neural and non‐neural crest cells as both of these cells migrate away from tissue explants. Using the Wnt1‐Cre/R26R mouse model, we have obtained a pure population of neural crest cells and established a primary CNC cell culture system in which the cell culture medium best supports the proliferation of E10.5 first branchial arch CNC cells and maintains these cells in their undifferentiated state. Differentiation of CNC cells can be initiated by switching to a differentiation medium. In this model, cultured CNC cells can give rise to neurons, glial cells, osteoblasts, and other cell types, faithfully mimicking the differentiation process of the post‐migratory CNC cells in vivo. Taken together, our study shows that the Wnt1‐Cre/R26R mouse first branchial arch provides an excellent model for obtaining post‐migratory neural crest cells free of any mesodermal contaminants. The cultured neural crest cells are under sustained proliferative, undifferentiated, or lineage‐enhanced conditions, hence, serving as a tool for the investigation of the regulatory mechanism of CNC cell fate determination in normal and abnormal craniofacial development. Developmental Dynamics 235:1433–1440, 2006. © 2005 Wiley‐Liss, Inc.
Transforming growth factor‐β stimulates epithelial–mesenchymal transformation in the proepicardium
Authors: Olivey Harold E. , Mundell Nathan A. , Austin Anita F. , Barnett Joey V.
Published: October 2005

The proepicardium (PE) migrates over the heart and forms the epicardium. A subset of these PE‐derived cells undergoes epithelial–mesenchymal transformation (EMT) and gives rise to cardiac fibroblasts and components of the coronary vasculature. We report that transforming growth factor‐β (TGFβ) 1 and TGFβ2 increase EMT in PE explants as measured by invasion into a collagen gel, loss of cytokeratin expression, and redistribution of ZO1. The type I TGFβ receptors ALK2 and ALK5 are both expressed in the PE. However, only constitutively active (ca) ALK2 stimulates PE‐derived epithelial cell activation, the first step in transformation, whereas caALK5 stimulates neither activation nor transformation in PE explants. Overexpression of Smad6, an inhibitor of ALK2 signaling, inhibits epithelial cell activation, whereas BMP7, a known ligand for ALK2, has no effect. These data demonstrate that TGFβ stimulates transformation in the PE and suggest that ALK2 partially mediates this effect. Developmental Dynamics 235:50–59, 2006. © 2005 Wiley‐Liss, Inc.
Novel scavenger receptor gene is differentially expressed in the embryonic and adult mouse testis
Authors: Sarraj M.A. , McClive P.J. , Wilmore H.P. , Loveland K.L. , Sinclair A.H.
Published: October 2005

In an effort to understand the mechanisms that underpin gonadal differentiation at the time of sex determination, we identified a cDNA encoding a putative novel testis expressed scavenger receptor, Tesr. Based on its domain structure, we hypothesize that the function of Tesr is similar to that of other scavenger receptors that play roles in phagocytosis of apoptotic cells, cell–cell adhesion, and defense. Tesr mRNA was detected in fetal mouse gonads of both sexes at 11.5 days post coitum (dpc). From 12.0 dpc, Tesr expression rapidly decreased in the female and was maintained in the male. Expression was seen in embryonic mouse sites other than the testis, such as in brain, eye, head, heart, neural arch, and cartilage primordium. Tesr expression in the newborn testis was faint to undetectable, but it increased from 2 days postpartum (dpp) until 15 dpp and was found in a subset of interstitial cells and in germ and Sertoli cells. Tesr mRNA in the adult mouse testis was observed in Sertoli cells, spermatogonia, spermatocytes, round spermatids, and in a subset of interstitial cells. We conclude that Tesr is differentially expressed in the male vs. female embryonic gonad and is expressed in both the ovary and the testes postnatally after 2 dpp. Developmental Dynamics 234:1026–1033, 2005. © 2005 Wiley‐Liss, Inc.
Developmental expression analysis of the mouse and chick orthologues of IRF6: The gene mutated in Van der Woude syndrome
Authors: Knight Alexandra S. , Schutte Brian C. , Jiang Rulang , Dixon Michael J.
Published: October 2005

Development of the lip and palate involves a complex series of events that are frequently disturbed resulting in the congenital anomalies cleft lip and cleft palate. Van der Woude syndrome (VWS) is an autosomal dominant disorder that is characterised by cleft lip, cleft palate, lower lip pits, and hypodontia. VWS arises as the result of mutations in the gene encoding interferon regulatory factor 6 (IRF6). To provide insights into the role of IRF6 during embryogenesis, we have analysed the expression of this molecule during mouse and chick facial development. Irf6 was expressed in the ectoderm covering the facial processes during their fusion to form the upper lip and primary palate in both mouse and chick. However, while Irf6 was expressed in the medial edge epithelia of the developing secondary palate of the mouse, which fuses as in man, Irf6 was not expressed in the medial edge epithelia of the naturally cleft chick secondary palate. Similarly, Irf6 was found to be down‐regulated in the medial edge epithelia of transforming growth factor beta3‐null mice, which also exhibit cleft palate. Together, these results support a role for IRF6 during the fusion events that occur during development of the lip and palate. Developmental Dynamics 235:1441–1447, 2006. © 2005 Wiley‐Liss, Inc.
Characterization of pegylated copolymeric micelles and in vivo pharmacokinetics and biodistribution studies
Authors: Lin Wen‐Jen , Chen Yi‐Chen , Lin Chi‐Chang , Chen Chau‐Fong , Chen Ji‐Wang
Published: October 2005

The aim of this study was to evaluate the influence of pegylated copolymeric micelle carrier on the biodistribution of drug in rats. The copolymers were synthesized via a modified ring‐opening copolymerization of lactone monomers (ϵ‐caprolactone, δ‐valerolactone, L‐lactide) and poly(ethylene glycol) (PEG10,000 and PEG4000). The molecular weights and the polydispersities of synthesized copolymers were in the range of 15,000–31,000 g/mol and 1.7–2.7, respectively. All of the pegylated amphiphilic copolymers were micelles formed with low CMC values in the range of 10−7–10−8M. The drug‐loaded micelles were prepared via a dialysis method. The average particle size of micelles was around 150–200 nm. The cytotoxicity in terms of cell viability after treated with PCL–PEG, PVL–PEG, and PLA–PEG micelles was insignificant. PCL–PEG and PVL–PEG micelles without branch side chain in structures had higher drug loading than PLA–PEG micelles. In vitro release profiles indicated the release of indomethacin from these micelles exhibited a sustained release behavior. The similar phenomenon was also observed in vivo in rats. The pegylated copolymeric micelles not only decreased drug uptake by the liver and kidney, but also prolonged drug retention in the blood. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Effects of adhesive systems and luting agents on bonding of fiber posts to root canal dentin
Authors: Monticelli Francesca , Osorio Raquel , Albaladejo Alberto , Aguilera Fatima S. , Ferrari Marco , Tay Franklin R. , Toledano Manuel
Published: October 2005

The study evaluated the influence of different luting materials on the microtensile bond strength of glass fiber posts to root canal dentin. Thirty extracted maxillary premolars were endodontically treated, and the roots were prepared for post cementation using the FRC Postec system (Vivadent). Two luting materials (Multilink, Vivadent and Clearfil Photo Core, Kuraray) were used in combination with three adhesive: Multilink Primer (Vivadent), Clearfil Photo Bond, and Clearfil New Bond (Kuraray). A composite build‐up was performed around the root to provide adequate gripping during testing. Specimens were cut to obtain beams with the post in the center and with the radicular dentin overlaid by the composite build‐up on each side. Microtensile testing was performed with a universal testing machine at a cross‐head speed of 0.5 mm/min. The failure mode was classified under a stereomicroscope and four representative beams of each group were selected for SEM analysis. Bond strength data that were analyzed with two‐way ANOVA and Student‐Newman‐Keuls multiple comparisons tests revealed that adhesive systems, luting materials, and the interaction between these two factors significantly influenced the bond strength results (p < 0.01). Multilink applied with its own adhesive system obtained the best results, while the lowest bond strength was achieved with clearfil photo core in combination with multilink primer. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
In vitro studies on the influence of precultural conditioning method on osteoblast reactions of a new type of injectable calcium cement material
Authors: Chai Feng , Blanchemain Nicolas , Lefèvre Annie , Hildebrand Hartmut F.
Published: October 2005

A new injectable dicalcium phosphate dehydrate (DCPD)‐based cement material “PD” VitalOs Cement® was studied to elucidate the process of equilibrium occurring in the early stage of implantation. The present study investigated the pH variations of the cement sample‐immersing culture medium at determined intervals, time‐dependent calcium/phosphate release, cell proliferation, and vitality in the cells–cement coculture milieu, after different preculture conditionings of the samples. Measurement of pH variation showed that without renewing the medium, pH value of sample lixiviate medium first dropped and, after 70 h, gradually balanced. When medium was renewed each day, pH value of lixiviate medium first descended and, after 24 h, gradually returned to pH 7.2. The cell viability revealed an excellent cytocompatibility of the cement. Both cell proliferation and vitality test showed that the preculture conditioning treatment is important at least for good performance of osteoblasts growing on the surface of calcium phosphate hydraulic cement (CPHC) samples in vitro. The results of calcium and phosphate assays clearly showed that this cement material can continuously dissolve to release calcium and phosphate in the liquid cell culture environment. The decrease of proliferation in some experimental groups with short conditioning is due to an excess of acid, which still can have some influence on cell growth after 24 h, since the biological milieu is not continuously renewed as in in vivo conditions. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Enhanced cell‐seeding into 3D porous scaffolds by use of magnetite nanoparticles
Authors: Shimizu Kazunori , Ito Akira , Honda Hiroyuki
Published: October 2005

To engineer functional tissues, a large number of cells must be successfully seeded into scaffolds. We previously proposed a methodology for tissue engineering using magnetite nanoparticles and magnetic force, which we termed “Mag‐TE.” In the present study, we applied the Mag‐TE technique to a cell seeding process and have termed the technique “Mag‐seeding.” The cell‐seeding efficiency of NIH/3T3 fibroblasts (FBs) by Mag‐seeding was investigated using six types of commercially available scaffolds (5 collagen sponges and 1 D,D‐L,L polylactic acid sponge) having various pore sizes. FBs were magnetically labeled with our original magnetite cationic liposomes (MCLs), which have a positive surface charge, to improve adsorption onto the cell surface. FBs labeled with MCLs were seeded onto a scaffold, and a magnet (4 kG) was placed under the scaffold. Mag‐seeding facilitated successful cell seeding into the deep internal space of the scaffolds. Cell‐seeding efficiency increased significantly in all scaffolds when compared to those without magnetic force. Moreover, when a high‐intensity magnet (10 kG) was used, cell‐seeding efficiency was significantly enhanced. These results suggest that Mag‐seeding is a promising approach for tissue engineering. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
In vitro and in vivo evaluation of ultrananocrystalline diamond for coating of implantable retinal microchips
Authors: Xiao Xingcheng , Wang Jian , Liu Chao , Carlisle John A. , Mech Brian , Greenberg Robert , Guven Dilek , Freda Ricardo , Humayun Mark S. , Weiland James , Auciello Orlando
Published: October 2005

In this work, ultrananocrystalline diamond (UNCD) thin films were evaluated for use as hermetic and bioinert coatings for a retinal microchip. These films were deposited on highly conductive Si substrates at different temperatures (from 400 to 800°C), using microwave plasma enhanced chemical vapor deposition with argon‐rich Ar/CH4 gas mixtures and different relative amounts of hydrogen (0–20%). Scanning electron microscopy studies showed that all the films are dense and continuous. Results of cyclic voltammetry test revealed that when there was <2% of hydrogen in the plasma, the film obtained renders the surface electrochemically inactive, with very low leakage currents (∼4 × 10−7 A/cm2 at ±5 V). In addition, in vivo tests of the UNCD‐coated Si samples were performed by implanting them in the eyes of rabbits for 4–6 months within the eye physiological environment. According to all these results, it was concluded that UNCD is a promising candidate for use as the encapsulating coatings for implantable retinal microelectronic devices. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Embedding a latin square in a pair of orthogonal latin squares
Authors: Jenkins Peter
Published: October 2005

In this paper, it is shown that a latin square of order n with n ≥ 3 and n ≠ 6 can be embedded in a latin square of order n2 which has an orthogonal mate. A similar result for idempotent latin squares is also presented. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 270–276, 2006
Arc‐transitive homogeneous factorizations and affine planes
Authors: Lim Tian Khoon
Published: October 2005

We study arc‐transitive homogeneous factorizations of a complete graph on 81 vertices and give an almost complete description of all possible factors that arise. In particular, we show that there exists an arc‐transitive homogeneous factorization of K81 such that the factors are isomorphic to the Hamming graph H(9,2). This gives rise to an edge partition of K81 into 90 copies of K9 and it turns out that these copies of K9 form the blocks of the exceptional nearfield affine plane of order 9. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 290–300, 2006
Effect of laminin‐1 on intestinal cell differentiation involves inhibition of nuclear nucleolin
Authors: Turck Natacha , Lefebvre Olivier , Gross Isabelle , Gendry Patrick , Kedinger Michèle , Simon‐Assmann Patricia , Launay Jean‐François
Published: October 2005

Intestinal epithelial cells are characterized by continuous renewal and differentiation events, which may be influenced by the basement membrane, and in particular laminins, which are major components of this specialized extracellular matrix. The function and signaling pathways of laminins in these processes are still poorly documented. In this study, we investigated the possible role and the subcellular localization of nucleolin, a nuclear shuttling protein, in relation to differentiation of human intestinal epithelial Caco2/TC7 cells triggered by exogenous laminin‐1. Immunofluorescence and Western blot analysis indicated that laminin‐1 induced early differentiation of the cells concomitantly to a decrease in nuclear nucleolin and its a cell surface location. We also showed that both effects of laminin‐1 on Caco2/TC7 cells—induction of the differentiation marker sucrase‐isomaltase and redistribution of nucleolin—could be mediated by a β1‐integrin dependent cascade that implicated activation of the p38 MAPK pathway. In addition, knock‐down of nucleolin expression by the small interfering RNA strategy mimicked the effect of laminin‐1 as it resulted in the induction of cell polarization and differentiation. Thus, our study suggests that changes in the subcellular distribution and expression level of nucleolin play an important role in intestinal cell differentiation and relay the signaling pathway induced by laminin‐1. J. Cell. Physiol. 206: 545–555, 2006. © 2005 Wiley‐Liss, Inc.
MyoD recruits the cdk9/cyclin T2 complex on Myogenic‐genes regulatory regions
Authors: Giacinti Cristina , Bagella Luigi , Puri Pier Lorenzo , Giordano Antonio , Simone Cristiano
Published: October 2005

During skeletal myogenesis, muscle‐regulatory factors bHLH and MEF2 promote the expression of muscle‐specific genes by recruiting several chromatin‐modifying complexes on specific DNA regulatory sequences. A number of MyoD‐interacting proteins have been reported, but whether they are recruited to the chromatin of myogenic loci, and the relationship with other chromatin bound proteins is unknown. We show that MyoD recruits cdk9/cyclin T2, together with the histone acetyltransferases p300 and PCAF, and the chromatin remodeling complex SWI/SNF, on promoters and enhancers of muscle‐specific genes, and that this event correlates with the acetylation of histone tails, remodeling of chromatin, and phosphorylation of the C‐terminal domain (CTD) of the RNA polymerase II at these elements. J.Cell.Physiol. © 2005 Wiley‐Liss, Inc.
Polypeptide encoded by mouse ZP3 exon‐7 Is Necessary and Sufficient for binding of mouse sperm in vitro
Authors: Williams Zev , Litscher Eveline S. , Jovine Luca , Wassarman Paul M.
Published: October 2005

Fertilization in mice is initiated by species‐specific binding of sperm to mZP3, one of three mouse zona pellucida (ZP) glycoproteins. At nanomolar concentrations, purified egg mZP3 binds to acrosome‐intact sperm heads and inhibits binding of sperm to eggs in vitro. Although several reports suggest that sperm recognize and bind to a region of mZP3 encoded by mZP3 exon‐7 (so‐called, sperm combining‐site), this issue remains controversial. Here, exon‐swapping and an IgG(Fc) fusion construct were used to further evaluate whether mZP3 exon‐7 is essential for binding of sperm to mZP3. In one set of experiments, hamster ZP3 (hZP3) exon‐6, ‐7, and ‐8 were individually replaced with the corresponding exon of mZP3. Stably transfected embryonal carcinoma (EC) cell lines carrying the recombinant genes were produced and secreted recombinant glycoprotein was purified and assayed for the ability to inhibit binding of sperm to eggs. While EC‐hZP3, a recombinant form of hZP3 made by EC cells, is unable to inhibit binding of mouse sperm to eggs in vitro, the results suggest that substitution of mZP3 exon‐7 for hZP3 exon‐7, but not mZP3 exon‐6 or ‐8, can impart inhibitory activity to EC‐hZP3. In this context, a fusion construct consisting of human IgG(Fc) and mZP3 exon‐7 and ‐8 was prepared, an EC cell line carrying the recombinant gene was produced, and secreted chimeric glycoprotein, called EC‐huIgG(Fc)/mZP3(7), was purified and assayed. It was found that the chimeric glycoprotein binds specifically to plasma membrane overlying sperm heads to a similar extent as egg mZP3 and, at nanomolar concentrations, inhibits binding of mouse sperm to eggs in vitro. Collectively, these observations provide new evidence that sperm recognize and bind to a region of mZP3 polypeptide immediately downstream of its ZP domain that is encoded by mZP3 exon‐7. The implications of these findings are discussed. J. Cell. Physiol. 207: 30–39, 2006. © 2005 Wiley‐Liss, Inc.
Hamiltonian cycles and paths with a prescribed set of edges in hypercubes and dense sets
Authors: Caha Rostislav , Koubek V.
Published: October 2005

This paper studies techniques of finding hamiltonian paths and cycles in hypercubes and dense sets of hypercubes. This problem is, in general, easily solvable but here the problem was modified by the requirement that a set of edges has to be used in such path or cycle. The main result of this paper says that for a given n, any sufficiently large hypercube contains a hamiltonian path or cycle with prescribed n edges just when the family of the edges satisfies certain natural necessary conditions. Analogous results are presented for dense sets. © 2005 Wiley Periodicals, Inc. J Graph Theory
Analogue forecasting of New Zealand climate anomalies
Authors: Mullan A. Brett , Thompson Craig S.
Published: October 2005

An analogue forecast scheme is described for multifield prediction of monthly and seasonal New Zealand climate anomalies on the basis of the methodology of Livezey and Barnston (1988) for US seasonal temperatures. The method is applied to predicting terciles of temperature and precipitation for six regions of New Zealand. Empirical orthogonal function analysis is used to reduce sea surface temperature and sea‐level pressure predictors down to a set of five independent indices, which incorporate variations due to El Niño‐Southern Oscillation, Indian Ocean sea temperatures and a wave 3 pattern in the Southern Hemisphere westerlies. A full bootstrap cross‐validation procedure is carried out, along with Monte Carlo tests, to assess the skill of the method on independent data and to determine the significance of the results. Significant skill is found for seasonal temperature forecasts for the summer and winter seasons; there is less success in predicting monthly temperatures or rainfall at either timescale. Considerable care is required to constrain the climate state vector, from which analogues are defined, and to constrain the search procedure itself, in order to produce results that are stable with respect to small parameter changes in the model. For the New Zealand region, 5 to 7 is found to be the optimum number of ‘closest analogues’, and the inclusion of anti‐analogues improves the predictions, at least in the seasonal case. Skill in predicting regional temperature and rainfall is shown to be related to a combination of skill in predicting sea‐level pressure patterns and to how strongly these patterns project onto temperature and rainfall anomalies. Copyright © 2005 Royal Meteorological Society.
Our approach to pediatric dermatologic laser surgery
Authors: Chapas Anne M. , Geronemus Roy G.
Published: October 2005

Background and Objectives

Many pediatric dermatological conditions may be successfully treated with laser surgery.

Study Design/Materials and Methods

The clinical approach to various pediatric dermatological conditions utilizing laser treatment options is discussed.

Results

Clinical uses of various modalities such as pulsed dye laser, KTP laser, Nd‐YAG laser, Q‐switched ruby laser, erbium‐YAG laser, diode laser, non‐coherent blue light sources, and fractional resurfacing are presented with successful parameters, developed over 22 years, utilized on a daily basis in a laser surgery clinic.

Conclusion

Laser surgery can make a significant improvement in many pediatric skin lesions, thanks to the unique properties of pediatric skin and a vast array of laser technologies. Lasers Surg. Med. 37:255–263, 2005. © 2005 Wiley‐Liss, Inc.
A Novel Injectable Poly(ε‐caprolactone)/Calcium Sulfate System for Bone Regeneration: Synthesis and Characterization
Authors: La Gatta Annalisa , De Rosa Alfredo , Laurienzo Paola , Malinconico Mario , De Rosa Mario , Schiraldi Chiara
Published: October 2005

Summary: A novel poly(ε‐caprolactone)/calcium sulfate system was prepared and characterized in order to enhance calcium sulfate (gypsum) performance as bone graft substitute overcoming its brittleness and fast resorption rate. A poly(ε‐caprolactone) (PCL) photo‐crosslinkable derivative (PCLf) was synthesized by reaction of a low molecular weight PCL diol with methacryloyl chloride and confirmed by FT‐IR and 1H NMR analyses. An injectable and easy mouldable mixture of PCLf and calcium sulfate hemi‐hydrate (PCLf/CHS) was obtained. Thermal analyses and solvent extraction proved the occurrence of PCLf photo‐crosslinking, even in the presence of CHS, in a time suitable for clinical applications. Swelling studies demonstrated that the encapsulation of the inorganic filler increases network hydrophilicity making it more permeable to water. Scanning electron microscopy, performed on crosslinked PCLf/CHS and on the same material after incubation in a PBS solution, showed the feasibility to obtain, in situ, gypsum entrapped into a degradable polymeric network. In vitro cytotoxicity tests, performed according to ISO 10993‐5, proved that the developed system was not cytotoxic supporting its potential use in tissue engineering as a new, injectable, photocurable bone graft material.

SEM micrograph of calcium sulfate di‐hydrate (gypsum) entrapped in the PCL network.

magnified image

SEM micrograph of calcium sulfate di‐hydrate (gypsum) entrapped in the PCL network.