bluuebunny/crossref_metadata_2025 huggingface dataset:
On the orbital motion of a rotating inner cylinder in annular flow
Authors: Feng Shunxin , Li Qibing , Fu Song
Published: November 2006

In this paper, numerical calculations have been performed to analyse the influence of the orbital motion of an inner cylinder on annular flow and the forces exerted by the fluid on the inner cylinder when it is rotating eccentrically. The flow considered is fully developed laminar flow driven by axial pressure gradient. It is shown that the drag of the annular flow decreases initially and then increases with the enhancement of orbital motion, when it has the same direction as the inner cylinder rotation. If the eccentricity and rotation speed of the inner cylinder keep unchanged (with respect to the absolute frame of reference), and the orbital motion is strong enough that the azimuthal component (with respect to the orbit of the orbital motion) of the flow‐induced force on the inner cylinder goes to zero, the flow drag nearly reaches its minimum value. When only an external torque is imposed to drive the eccentric rotation of the inner cylinder, orbital motion may occur and, in general, has the same direction as the inner cylinder rotation. Under this condition, whether the inner cylinder can have a steady motion state with force equilibrium, and even what type of motion state it can have, is related to the linear density of the inner cylinder. Copyright © 2006 John Wiley & Sons, Ltd.
Use of single saphenous interposition vein graft for primary arterial circuit and secondary recipient site in head and neck reconstruction: A case report
Authors: Chang Kao‐Ping , Lee Hsiao‐Chen , Lai Chung‐Sheng , Lin Sin‐Daw
Published: November 2006

Background.

Autologous vein grafts are a valuable tool in microsurgical free tissue transfer. Interposition vein grafts offer the surgeon greater freedom when placing the free flap and choosing the recipient vessels, providing valuable options in case recipient vessels are not available for those patients with large wounds. Free flaps transferred to head and neck regions carry a higher risk of failure, which may be expected to increase more with the use of vein grafts.

Methods.

We present our case with the double use of a single vein graft for both primary arterial conduit in end‐to‐end fashion and secondary end‐to‐side recipient site in the microsurgical reconstruction of a complicated head and neck defect.

Results.

All these anastomoses and flaps survived perfectly, and the patient was discharged 14 days after the transfer of the second flap.

Conclusion.

Although the anastomosis of 2 flaps to a single vein graft was successful in our case, it represents a higher risk option than different recipient vessels. We provide this alternative procedure in selected patients, as there is no other receipt vessel or recipient blood flow strong enough to supply more than 1 flap. © 2006 Wiley Periodicals, Inc. Head Neck, 2007
Intraoral proliferative myositis: Case report and literature review
Authors: Brooks John K. , Scheper Mark A. , Kramer Richard E. , Papadimitriou John C. , Sauk John J. , Nikitakis Nikolaos G.
Published: November 2006

Background.

Proliferative myositis is a rare, benign, reactive intramuscular lesion of fibroblastic/myofibroblastic origin; an identical lesion in a subcutaneous or fascial location is referred to as proliferative fasciitis. The rapid growth rate and unusual histopathologic features have frequently been mistaken for a malignant process and have promoted unnecessary invasive procedures. Here we present only the third oral case of proliferative myositis, arising from the tongue of a 65‐year‐old man.

Methods and Results.

Histologically, the resected lesion was composed of numerous fibroblastic or myofibroblastic spindle cells and variable numbers of large ganglion‐like cells infiltrating between and around muscle fascicles, resembling a “checkerboard” configuration. A demographic profile of proliferative myositis of the head and neck is also provided, compiled from 19 patients culled from an English‐language literature review and this report.

Conclusions.

Incisional biopsy or fine‐needle aspiration biopsy of proliferative myositis of the head and neck should lead to spontaneous resolution and is, therefore, sufficient to render the diagnosis and to provide conservative treatment. Recurrence is extremely rare. © 2006 Wiley Periodicals, Inc. Head Neck, 2007
In vivo response to starch‐based scaffolds designed for bone tissue engineering applications
Authors: Salgado A.J. , Coutinho O.P. , Reis R.L. , Davies J.E.
Published: November 2006

Our purpose was to evaluate the in vivo endosseous response to three starch‐based scaffolds implanted in rats (n = 54). We implanted the three scaffold groups; a 50/50 (wt %) blend of corn starch and ethylene‐vinyl alcohol (SEVA‐C), the same composition coated with a biomimetic calcium phosphate (Ca‐P) layer (SEVA‐C/CaP), and a 50/50 (wt %) blend of corn starch and cellulose acetate (SCA), all produced by extrusion with blowing agents, into distal femurs proximal to the epiphyseal plate, for 1, 3, or 6 weeks. Our results showed that at 1 week considerable reparative bone formed around all scaffold groups, although the bone was separated from the scaffold by an intervening soft tissue interfacial zone that comprised two distinct compartments: the surface of the scaffold was occupied by multinucleate giant cells and the compartment between these cells and the surrounding bone was occupied by a streaming fibrous‐like tissue. The extracellular matrix of the latter was continuous with the extracellular bone matrix itself, labeled positively for osteocalcin and appeared mineralized by back‐scattered electron imaging. All three scaffolds showed a similar tissue response, with the soft tissue interface diminishing with time. No bone contact was observed with SEVA‐C at any time point, only transitory bone contact was observed with SEVA‐C/CaP at 3 weeks, but SCA exhibited direct bone contact at 6 weeks where 56.23 ± 6.46% of the scaffold surface was occupied by bone. We conclude that all materials exhibited a favorable bony response and that the rapidly forming initial “connective tissue” seen around all scaffolds was a very early form of bone formation. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Preclinical biocompatibility assessment of the EVAHEART ventricular assist device: Coating comparison and platelet activation
Authors: Snyder Trevor A. , Tsukui Hiroyuki , Kihara Shin'Ichiro , Akimoto Takehide , Litwak Kenneth N. , Kameneva Marina V. , Yamazaki Kenji , Wagner William R.
Published: November 2006

Thromboembolism and bleeding remain significant complications of ventricular assist device (VAD) support. Increasing the amount of biocompatibility data collected during preclinical studies can provide additional criteria to evaluate device refinements, while design changes may be implemented before entering clinical use. Twenty bovines were implanted with the EVAHEART centrifugal VAD for durations from 30 to 196 days. Titanium alloy pumps were coated with either diamond‐like carbon or 2‐methoxyethyloylphosphoryl choline (MPC). Activated platelets and platelet microaggregates were quantified by flow cytometry, including two new assays to quantify bovine platelets expressing CD62P and CD63. Temporally, all assays were low preoperatively, then significantly increased following VAD implantation, before declining to a lower, but still elevated level over 2–3 weeks. MPC‐coated VADs produced significantly fewer activated platelets after implant trauma effects diminished. Three animals receiving no postoperative anticoagulation had similar amounts of circulating activated platelets and platelet microaggregates as animals receiving warfarin anticoagulation. Two new methods to quantify bovine activated platelets using antibodies to CD62P and CD63 were characterized and applied. These measures, along with previously described assays, were able to differentiate between two biocompatible coatings and assess effects of anticoagulation regimen in VAD preclinical testing. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Comparison of the clinical and preclinical biocompatibility testing of dental materials: Are the ISO usage tests meaningful?
Authors: Murray Peter E. , Garcia‐Godoy Franklin
Published: November 2006

International Organization for Standardization (ISO 10993 and 7405) guidelines recommends the preclinical screening of dental materials using non‐human primates. The literature contains no comparisons of responses to dental materials. To test the accuracy of preclinical screening tests for predicting human clinical responses, 106 class V pulp exposed cavities were prepared in human and non‐human primate teeth. Teeth were restored with calcium hydroxide and amalgam, zinc oxide eugenol or resin‐modified glass ionomer. Teeth were extracted after 10–163 days and prepared for histological analysis. Pulp cell numbers were compared and their reactionary dentin activity measured in response to cavity preparation. Pulp inflammatory activity was categorized according to ISO standards. There were no statistically significant differences between human and non‐human primate teeth in terms of pulp reactions to dental materials. The use of non‐human primates for preclinical biocompatibility investigation provided an accurate method of evaluating clinical responses to dental materials. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Surface functional group dependent apatite formation on bacterial cellulose microfibrils network in a simulated body fluid
Authors: Nge Thi Thi , Sugiyama Junji
Published: November 2006

The apatite forming ability of biopolymer bacterial cellulose (BC) has been investigated by soaking different BC specimens in a simulated body fluid (1.5 SBF) under physiological conditions, at 37°C and pH 7.4, mimicking the natural process of apatite formation. From ATR‐FTIR spectra and ICP‐AES analysis, the crystalline phase nucleated on the BC microfibrils surface was calcium deficient carbonated apatite through initial formation of octacalcium phosphate (OCP) or OCP like calcium phosphate phase regardless of the substrates. Morphology of the deposits from SEM, FE‐SEM, and TEM observations revealed the fine structure of thin film plates uniting together to form apatite globules of various size (from <1 μm to 3 μm) with respect to the substrates. Surface modification by TEMPO (2,2,6,6‐tetramethylpyperidine‐1‐oxyl)‐mediated oxidation, which can readily form active carboxyl functional groups upon selective oxidation of primary hydroxyl groups on the surface of BC microfibrils, enhanced the rate of apatite nucleation. Ion exchanged treatment with calcium chloride solution after TEMPO‐mediated oxidation was found to be remarkably different from other BC substrates with the highest deposit weight and the smallest apatite globules size. The role of BC substrates to induce mineralization rate differs according to the nature of the BC substrates, which strongly influences the growth behavior of the apatite crystals. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Tissue factor and thrombomodulin expression on endothelial cell‐seeded collagen modules for tissue engineering
Authors: She Mingyu , McGuigan Alison P. , Sefton Michael V.
Published: November 2006

The creation of functional tissue engineering constructs to repair or replace diseased tissues requires a well‐formed vasculature network within the construct and the endothelial cells lining that vascular bed must display a nonthrombogenic phenotype. A new approach to tissue engineering involves the assembly of smaller components (modules fabricated at the hundred micron scale) into larger constructs. The modules, collagen gel containing the particular tissue cell of interest, are covered with endothelial cells prior to assembly so that the interconnected channels that are formed are lined with endothelial cells, creating a mimic of a vascular network. Here, we confirmed (using confocal microscopy primarily) that the human umbilical vein endothelial cells, seeded on collagen gel modules without a second embedded cell and without flow, bore the molecular markers of low thrombogenicity. Two days, after seeding on the modules, endothelial cells displayed the typical cobblestone morphology, formed tight cell–cell junctions and covered the whole module surface. Immunofluorescence staining showed that at both 2 days and 7 days after seeding, only a few cells expressed tissue factor while this number was dramatically increased after TNFα stimulation. On the other hand, thrombomodulin was expressed by the majority of seeded cells and expression was reduced after TNFα stimulation. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
The role of biological extracellular matrix scaffolds in vascularized three‐dimensional tissue growth in vivo
Authors: Cronin Kevin J. , Messina Aurora , Thompson Erik W. , Morrison Wayne A. , Stevens Geoffrey W. , Knight Kenneth R.
Published: November 2006

An in vivo murine vascularized chamber model has been shown to generate spontaneous angiogenesis and new tissue formation. This experiment aimed to assess the effects of common biological scaffolds on tissue growth in this model. Either laminin‐1, type I collagen, fibrin glue, hyaluronan, or sea sponge was inserted into silicone chambers containing the epigastric artery and vein, one end was sealed with adipose tissue and the other with bone wax, then incubated subcutaneously. After 2, 4, or 6 weeks, tissue from chambers containing collagen I, fibrin glue, hyaluronan, or no added scaffold (control) had small amounts of vascularized connective tissue. Chambers containing sea sponge had moderate connective tissue growth together with a mild “foreign body” inflammatory response. Chambers containing laminin‐1, at a concentration 10‐fold lower than its concentration in Matrigel™, resulted in a moderate adipogenic response. In summary, (1) biological hydrogels are resorbed and gradually replaced by vascularized connective tissue; (2) sponge‐like matrices with large pores support connective tissue growth within the pores and become encapsulated with granulation tissue; (3) laminin‐containing scaffolds facilitate adipogenesis. It is concluded that the nature and chemical composition of the scaffold exerts a significant influence on the amount and type of tissue generated in this in vivo chamber model. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Histological and histomorphometrical comparative study of the degradation and osteoconductive characteristics of α‐ and β‐tricalcium phosphate in block grafts
Authors: Yamada Masahiro , Shiota Makoto , Yamashita Yasuo , Kasugai Shohei
Published: November 2006

The purpose of the present study was to compare α‐ and β‐tricalcium phosphate (TCP) as bone graft material for augmenting highly resorbed alveolar ridges. The cranial bones of 15 rabbits were used. Three titanium chambers filled with porous blocks of α‐TCP, β‐TCP, or blood clots were placed in each slit. The two TCP blocks had similar inner/outer structures and purities. Animals were sacrificed after 2, 4, and 8 weeks. Specimens were embedded in polyester resin as nondecalcified specimens, and evaluated both histologically and histomorphometrically. In both TCP groups, blocks had hardly degraded at 2 weeks while in the α‐TCP group, the block had notably started degrading after 4 weeks. In the β‐TCP group, degradation began at 4 weeks and this degradation had increased just slightly after 8 weeks. The α‐TCP block degraded significantly more than the β‐TCP block. Residual α‐TCP particles surrounded by newly formed bone decreased over time, and both particles and newly formed bone were simultaneously absorbed by osteoclast‐like cells. These observations suggest that residual α‐TCP particles surrounded by newly formed bone may disappear progressively from bone and could be incorporated into the bone remodeling cycle in combination with newly formed bone. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Internal adaptation and some physical properties of methacrylate‐based denture base resins polymerized by different techniques
Authors: Ganzarolli Solimar M. , Nunes de Mello José A. , Shinkai Rosemary S. , Del Bel Cury Altair A.
Published: November 2006

This study evaluated the internal adaptation, porosity, transverse and impact strength of three denture base polymers: (1) conventional heat‐polymerized, (2) microwave‐polymerized, and (3) injection‐molded resins. Internal adaptation was measured by weighing a vinyl polysiloxane film reproducing the gap between the denture base and the metallic master model of an edentulous maxilla. The measurements were performed immediately after finishing and after 30‐day storage in water. Porosity was evaluated by weighing each specimen in air and in water using an analytical scale balance. Transverse strength test (three‐point bending test) was performed using a universal machine under axial load, at a crosshead speed of 5 mm/min. Impact strength test (Charpy's test) was performed with a 40 kJ/cm load. Data were analyzed by ANOVA and Tukey test (α = 0.05). Internal adaptation, porosity, transverse and impact strength varied according to the type of acrylic resin and the processing technique. The injection‐molded resin showed better internal adaptation compared with the conventional heat‐polymerized and the microwave‐polymerized resins, particularly after 30 days, but there was no relevant improvement of porosity, transverse and impact strength. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Biocompatibility of electrophoretical deposition of nanostructured hydroxyapatite coating on roughen titanium surface: In vitro evaluation using mesenchymal stem cells
Authors: Chen F. , Lam W. M. , Lin C. J. , Qiu G. X. , Wu Z. H. , Luk K. D. K. , Lu W. W.
Published: November 2006

A nano hydroxyapatite (HAp) layer was coated on a roughen titanium surface by means of electrophoretic deposition with an acetic anhydride solvent system. The objectives of this current study are to investigate whether nano‐HAp can improve mechanical strength at a lower sintering temperature and biocompatibility. Densification temperature was lowered from usual 1000 to 800°C. The coating interfacial bonding strength, phase purity, microstructure, and biocompatibility were investigated. Degradation of HA phase was not detected in XRD. A porous TiO2 layer acts as a gradient coating layer with an intermediate thermal expansion coefficient between hydroxyapatite and titanium that reduces the thermal stress. From SEM image, the coating does not contain any crack. Mesenchymal stem cell (MSC) is the progenitor cell for various tissues in mature animals, which can improve integration of bone tissue into implant. In this in vitro study, rabbit MSCs culture indicated that the HAp/Ti nanocomposite biomaterial had good biocompatibility and bioactivity. Around materials and on its surface cell grew well with good morphology. Proliferation of the MSCs on the nano‐HAp coating was higher than its micron counterpart in XTT assay. These properties show potential for the orthopaedic and dental applications. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Material model measurements and predictions for a random pore poly(ϵ‐caprolactone) scaffold
Authors: Quinn T. P. , Oreskovic T. L. , Landis F. A. , Washburn N. R.
Published: November 2006

We investigated material models for a polymeric scaffold used for bone. The material was made by co‐extruding poly(ε‐caprolactone) (PCL), a biodegradable polyester, and poly(ethylene oxide) (PEO). The water soluble PEO was removed resulting in a porous scaffold. The stress–strain curve in compression was fit with a phenomenological model in hyperbolic form. This material model will be useful for designers for quasi‐static analysis as it provides a simple form that can easily be used in finite element models. The ASTM D‐1621 standard recommends using a secant modulus based on 10% strain. The resulting modulus has a smaller scatter in its value compared with the coefficients of the hyperbolic model, and it is therefore easier to compare differences in material processing and ensure quality of the scaffold. A prediction of the small–strain elastic modulus was constructed from images of the microstructure. Each pixel of the micrographs was represented with a brick finite element and assigned the Young's modulus of bulk PCL or a value of 0 for a pore. A compressive strain was imposed on the model and the resulting stresses were calculated. The elastic constants of the scaffold were then computed with Hooke's law for a linear‐elastic isotropic material. The model was able to predict the small–strain elastic modulus measured in the experiments to within one standard deviation. Thus, by knowing the microstructure of the scaffold, its bulk properties can be predicted from the material properties of the constituents. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Comparison of plateletpheresis on the Fresenius AS.TEC 204 and Haemonetics MCS 3p
Authors: Ranganathan Sudha
Published: November 2006

This is an attempt at comparing two cell separators for plateletpheresis, namely the Fresenius AS.TEC 204 and Haemonetics MCS 3p, at a tertiary care center in India. Donors who weighed between 55–75 kg, who had a hematocrit of 41–43%, and platelet counts of 250 × 103–400 × 103/μl were selected for the study. The comparability of the donors who donated on the two cell separators were analysed by t‐test independent samples and no significant differences were found (P > 0.05). The features compared were time taken for the procedure, volume processed on the separators, adverse reactions of the donors, quality control of the product, separation efficiency of the separators, platelet loss in the donors after the procedure, and the predictor versus the actual yield of platelets given by the cell separator. The volume processed to get a target yield of >3 × 1011 was equal to 2.8–3.2 l and equal in both the cell separators. Symptoms of citrate toxicity were seen in 4 and 2.5% of donors who donated on the MCS 3p and the AS.TEC 204, respectively, and 3 and 1% of donors, respectively, had vasovagal reactions. All the platelet products collected had a platelet count of >3 × 1011; 90% of the platelet products collected on the AS.TEC 204 attained the predicted yield that was set on the cell separator where as 75% of the platelet products collected on the MCS 3p attained the target yield. Quality control of the platelets collected on both the cell separators complied with the standards except that 3% of the platelets collected on the MCS 3p had a visible red cell contamination. The separation efficiency of the MCS 3p was higher, 50–52% as compared to the 40–45% on the AS.TEC 204. A provision of double venous access, less adverse reactions, negligible RBC contamination with a better predictor yield of platelets makes the AS.TEC 204 a safer and more reliable alternative than the widely used Haemonetics MCS 3p. J. Clin. Apheresis. © 2006 Wiley‐Liss, Inc.
Hyaline cartilage formation and enchondral ossification modeled with KUM5 and OP9 chondroblasts
Authors: Sugiki Tadashi , Uyama Taro , Toyoda Masashi , Morioka Hideo , Kume Shoen , Miyado Kenji , Matsumoto Kenji , Saito Hirohisa , Tsumaki Noriyuki , Takahashi Yoriko , Toyama Yoshiaki , Umezawa Akihiro
Published: November 2006

What is it that defines a bone marrow‐derived chondrocyte? We attempted to identify marrow‐derived cells with chondrogenic nature and immortality without transformation, defining “immortality” simply as indefinite cell division. KUM5 mesenchymal cells, a marrow stromal cell line, generated hyaline cartilage in vivo and exhibited enchondral ossification at a later stage after implantation. Selection of KUM5 chondroblasts based on the activity of the chondrocyte‐specific cis‐regulatory element of the collagen α2(XI) gene resulted in enhancement of their chondrogenic nature. Gene chip analysis revealed that OP9 cells, another marrow stromal cell line, derived from macrophage colony‐stimulating factor‐deficient osteopetrotic mice and also known to be niche‐constituting cells for hematopoietic stem cells expressed chondrocyte‐specific or ‐associated genes such as type II collagen α1, Sox9, and cartilage oligomeric matrix protein at an extremely high level, as did KUM5 cells. After cultured OP9 micromasses exposed to TGF‐β3 and BMP2 were implanted in mice, they produced abundant metachromatic matrix with the toluidine blue stain and formed type II collagen‐positive hyaline cartilage within 2 weeks in vivo. Hierarchical clustering and principal component analysis based on microarray data of the expression of cell surface markers and cell‐type‐specific genes resulted in grouping of KUM5 and OP9 cells into the same subcategory of “chondroblast,” that is, a distinct cell type group. We here show that these two cell lines exhibit the unique characteristics of hyaline cartilage formation and enchondral ossification in vitro and in vivo. J. Cell. Biochem. 100: 1240–1254, 2007. © 2006 Wiley‐Liss, Inc.
Mouse embryonic fibroblast cells from transgenic mice overexpressing tNOX exhibit an altered growth and drug response phenotype
Authors: Yagiz Kader , Wu Lion‐Ying , Kuntz Charles P. , James Morré D. , Morré Dorothy M.
Published: November 2006

Mouse embryonic fibroblast (MEF) cells prepared from transgenic mice overexpressing a cancer‐specific and growth‐related cell surface NADH oxidase with protein disulfide‐thiol interchange activity grew at rates approximately twice those of wild‐type embryonic fibroblast cells. Growth of transgenic MEF cells overexpressing tNOX was inhibited by low concentrations of the green tea catechin (−)‐epigallocatechin‐3‐gallate (EGCg) or the synthetic isoflavene phenoxodiol. Both are putative tNOX‐targeted inhibitors with anti‐cancer activity. With both EGCg and phenoxodiol, growth inhibition was followed after about 48 h by apoptosis. Growth of wild‐type mouse fibroblast cells from the same strain was unaffected by EGCg and phenoxodiol and neither compound induced apoptosis even at concentrations 100–1,000‐fold higher than those that resulted in apoptotic death in the transgenic MEF cells. The findings validate earlier reports of evidence for tNOX presence as contributing to unregulated growth of cancer cells as well as the previous identification of the tNOX protein as the molecular target for the anti‐cancer activities attributed to both EGCg and phenoxodiol. The expression of tNOX emerges as both necessary and sufficient to account for the cancer cell‐specific growth inhibitions by both EGCg and phenoxodiol. J. Cell. Biochem. 101: 295–306, 2007. © 2006 Wiley‐Liss, Inc.
Pair interaction energy decomposition analysis
Authors: Fedorov Dmitri G. , Kitaura Kazuo
Published: November 2006

The energy decomposition analysis (EDA) by Kitaura and Morokuma was redeveloped in the framework of the fragment molecular orbital method (FMO). The proposed pair interaction energy decomposition analysis (PIEDA) can treat large molecular clusters and the systems in which fragments are connected by covalent bonds, such as proteins. The interaction energy in PIEDA is divided into the same contributions as in EDA: the electrostatic, exchange‐repulsion, and charge transfer energies, to which the correlation (dispersion) term was added. The careful comparison to the ab initio EDA interaction energies for water clusters with 2–16 molecules revealed that PIEDA has the error of at most 1.2 kcal/mol (or about 1%). The analysis was applied to (H2O)1024, the α helix, β turn, and β strand of polyalanine (ALA)10, as well as to the synthetic protein (PDB code 1L2Y) with 20 residues. The comparative aspects of the polypeptide isomer stability are discussed in detail. © 2006 Wiley Periodicals, Inc.J Comput Chem 2007
N‐glycosylation of the Xenopus laevis ClC‐5 protein plays a role in cell surface expression, affecting transport activity at the plasma membrane
Authors: Schmieder Sandra , Bogliolo Stéphanie , Ehrenfeld Jordi
Published: November 2006

Mutations in the gene encoding ClC‐5 lead to X‐linked hypercalciuric nephrolithiasis (XLHN), characterized by proteinuria, hypercalciuria, and phosphaturia. In renal proximal tubule cells, ClC‐5 was identified as an important player in endocytosis, which ensures reabsorption of filtered protein. However, the recent finding that ClC‐5 is a Cl−/H+ antiporter and not a Cl− channel as long thought points to the lack of understanding of its functional role. Also, little biochemical data are available about ClC‐5 and its post‐translational modifications have not been investigated. Here, we examined the role of N‐glycosylation of xClC‐5 in the Xenopus oocyte expression system by comparing wild‐type (WT) xClC‐5 and N‐glycosylation site mutants. We found that xClC‐5 is N‐glycosylated on asparagines 169 and 470, which are the only N‐glycosylated sites. xClC‐5 mutants have an increased susceptibility to polyubiquitination and proteasomal degradation; however, without a notable impact on the expression level. Using a cross‐linking reagent, we showed that xClC‐5 assembles into protein complexes, independent of its N‐glycosylation. Voltage‐clamp measurements showed a reduced conductance in the presence of tunicamycin and with xClC‐5 N‐glycosylation site mutants. Using immunocytochemistry, we localized xClC‐5 mainly in intracellular compartments, and found that its cell surface pool is reduced in the absence of N‐glycans. We further examined the plasma membrane retrieval of WT and mutant xClC‐5 in the presence of Brefeldin A (BFA), and found that the non‐glycosylated mutant was retrieved more than five times faster than the WT protein. We conclude that N‐glycosylation enhances cell surface expression of xClC‐5, increasing its plasma membrane transport activity. J. Cell. Physiol. 210: 479–488, 2007. © 2006 Wiley‐Liss, Inc.
Patterning the developing and regenerating olfactory system
Authors: Henion Timothy R. , Schwarting Gerald A.
Published: November 2006

The olfactory system is a remarkable model for investigating the factors that influence the guidance of sensory axon populations to specific targets in the CNS. Since the initial discovery of the vast odorant receptor (ORs) gene family in rodents and the subsequent finding that these molecules directly influence targeting, several additional olfactory axon guidance cues have been identified. Two of these, ephrins and semaphorins, have well‐established functions in patterning axon connections in other systems. In addition, lactosamine‐containing glycans are also required for proper targeting and maintenance of olfactory axons, and may also function in other sensory regions. It is now apparent that these and likely other additional molecules are required along with ORs to orchestrate the complex pattern of convergence and divergence that is unique to the olfactory system. J. Cell. Physiol. 210: 290–297, 2007. © 2006 Wiley‐Liss, Inc.
Differentiation of human adult skin‐derived neuronal precursors into mature neurons
Authors: Gingras Marie , Champigny Marie‐France , Berthod François
Published: November 2006

The isolation of autologous neuronal precursors from skin‐derived precursor cells extracted from adult human skin would be a very efficient source of neurons for the treatment of various neurodegenerative diseases. The purpose of this study was to demonstrate that these neuronal precursors were able to differentiate into mature neurons. We isolated neuronal precursors from breast skin and expanded them in vitro for over ten passages. We showed that 48% of these cells were proliferating after the first passage, while this growth rate decreased after the second passage. We demonstrated that 70% of these cells were nestin‐positive after the third passage, while only 17% were neurofilament M‐positive after 7 days of differentiation. These neuronal precursors expressed βIII tubulin, the dendritic marker MAP2 and the presynaptic marker synaptophysin after 7 days of in vitro maturation. They also expressed the postsynaptic marker PSD95 and the late neuronal markers NeuN and neurofilament H after 21 days of differentiation, demonstrating they became terminally differentiated neurons. These markers were still expressed after 50 days of culture. The generation of autologous neurons from an accessible adult human source opens many potential therapeutic applications and has a great potential for the development of experimental studies on normal human neurons. J. Cell. Physiol. 210: 498–506, 2007. © 2006 Wiley‐Liss, Inc.
Mitogen activated protein kinase‐dependent activation of c‐Jun and c‐Fos is required for neuronal differentiation but not for growth and stress response in PC12 cells
Authors: Eriksson Minna , Taskinen Minna , Leppä Sirpa
Published: November 2006

MAPK‐dependent activation of AP‐1 protein c‐Jun is involved in PC12 cell differentiation and apoptosis. However, the role of other AP‐1 proteins and their connection to MAPKs during growth, differentiation and apoptosis has remained elusive. Here we studied the activation of AP‐1 proteins in response to ERK, JNK, and p38 signaling upon NGF, EGF and anisomycin exposures. All treatments caused different kinetics and strength of MAPK and AP‐1 activities. NGF induced persistent ERK and AP‐1 activities, whereas upon EGF and anisomycin exposures, their activities were only weakly and transiently induced. The sustained AP‐1 activity was associated with concomitant c‐Fos and c‐Jun expression and phoshorylation, which were JNK and ERK dependent. While inhibition of the ERK, JNK, and p38 activities partially prevented AP‐1 activity and suppressed differentiation, none of them was required for anisomycin‐induced apoptosis. The importance of c‐Fos and c‐Jun as mediators of differentiation was demonstrated by the findings that the corresponding siRNAs suppressed NGF‐induced neurite outgrowth. However, the capacity of c‐Fos to promote differentiation required cooperation with Jun proteins. In contrast, Fra‐2 expression was not required for the differentiation response. Together, the results show that sustained c‐Jun and c‐Fos activities mediate MAPK signaling and are essential for differentiation of PC12 cells. J. Cell. Physiol. 210: 538–548, 2007. © 2006 Wiley‐Liss, Inc.
Activation of the β myosin heavy chain promoter by MEF‐2D, MyoD, p300, and the calcineurin/NFATc1 pathway
Authors: Meissner Joachim D. , Umeda Patrick K. , Chang Kin‐Chow , Gros Gerolf , Scheibe Renate J.
Published: November 2006

Calcium is a key element in intracellular signaling in skeletal muscle. Changes in intracellular calcium levels are thought to mediate the fast‐to‐slow transformation of muscle fiber type. One factor implicated in gene regulation in adult muscle is the nuclear factor of activated T‐cells (NFAT) isoform c1, whose dephosphorylation by the calcium/calmodulin‐dependent phosphatase calcineurin facilitates its nuclear translocation. Here, we report that differentiated C2C12 myotubes predominantly expressing fast‐type MyHCII protein undergo fast‐to‐slow transformation following calcium‐ionophore treatment, with several transcription factors and a transcriptional coactivator acting in concert to upregulate the slow myosin heavy chain (MyHC) β promoter. Transient transfection assays demonstrated that the calcineurin/NFATc1 signaling pathway is essential for MyHCβ promoter activation during transformation of C2C12 myotubes but is not sufficient for complete fast MyHCIId/x promoter inhibition. Along with NFATc1, myocyte enhancer factor‐2D (MEF‐2D) and the myogenic transcription factor MyoD transactivated the MyHCβ promoter in calcium‐ionophore‐treated myotubes in a calcineurin‐dependent manner. To elucidate the mechanism involved in regulating MyHCβ gene expression, we analyzed the −2.4‐kb MyHCβ promoter construct forcis‐regulatory elements. Using electrophoretic mobility shift assays (EMSAs), chromatin immunoprecipitation assays (ChIP), and nuclear complex coimmunoprecipitation (NCcoIP) assays, we demonstrated calcium‐ionophore‐induced binding of NFATc1 to a NFAT consensus site adjacent to a MyoD‐binding E‐box. At their respective binding sites, both NFATc1 and MyoD recruited the transcriptional coactivator p300, and in turn, MEF‐2D bound to the MyoD complex. The calcium‐ionophore‐induced effects on the MyHCβ promoter were shown to be calcineurin‐dependent. Together, our findings demonstrate calcium‐ionophore‐induced activation of the β MyHC promoter by NFATc1, MyoD, MEF‐2D, and p300 in a calcineurin‐dependent manner. J. Cell. Physiol. 211: 138–148, 2007. © 2006 Wiley‐Liss, Inc.
Life without water: expression of plant LEA genes by an anhydrobiotic arthropod
Authors: Hand Steven C. , Jones Dana , Menze Michael A. , Witt Trudy L.
Published: November 2006

Anhydrobiotic animals protect cellular architecture and metabolic machinery in the dry state, yet the molecular repertoire supporting this profound dehydration tolerance is not fully understood. For the desiccation‐tolerant crustacean, Artemia franciscana, we report differential expression of two distinct mRNAs encoding for proteins that share sequence similarities and structural features with late‐embryogenesis abundant (LEA) proteins originally discovered in plants. Bioinformatic analyses support assignment of the LEA proteins from A. franciscana to group 3. This eucoelomate species is the most highly evolved animal for which LEA gene expression has been reported. It is becoming clear that an ensemble of micromolecules and macromolecules is important for establishing the physical conditions required for cellular stabilization during drying in nature. J. Exp. Zool. 305A:62–66, 2006. © 2006 Wiley‐Liss, Inc.
Nowhere‐zero flows in tensor product of graphs
Authors: Zhang Zhao , Zheng Yirong , Mamut Aygul
Published: November 2006

In this paper, we characterize graphs whose tensor product admit nowhere‐zero 3‐flow. The main result is: For two graphs G1 and G2 with δ ≥ 2 and G2 not belonging to a well‐characterized class of graphs, the tensor product of G1 and G2 admits a nowhere‐zero 3‐flow. © 2006 Wiley Periodicals, Inc. J Graph Theory 54: 284–292, 2007
Multivariate analysis approach to the plasma protein profile of patients with advanced colorectal cancer
Authors: Ragazzi Eugenio , Pucciarelli Salvatore , Seraglia Roberta , Molin Laura , Agostini Marco , Lise Mario , Traldi Pietro , Nitti Donato
Published: November 2006

The aim of the present study was to identify the pattern of plasma protein species of interest as markers of colorectal cancer (CRC). Using matrix‐assisted laser desorption/ionization‐mass spectrometry (MALDI‐MS), the plasma protein profile was determined in nine stage IV CRC patients (study group) and nine clean‐colon healthy subjects (control group). Multivariate analysis methods were employed to identify distinctive disease patterns at protein spectrum. In the study and control groups, cluster analysis (CA) on the complete MALDI‐MS spectra plasma protein profile showed a distinction between CRC patients and healthy subjects, thus allowing the identification of the most discriminating ionic species. Principal component analysis (PCA) and linear discriminant analysis (LDA) yielded similar grouping results. LDA with leave‐one‐out cross validation achieved a correct classification rate of 89% in both the patients and the healthy subjects. Copyright © 2006 John Wiley & Sons, Ltd.
Seasonality of the northern hemisphere circumpolar vortex
Authors: Wrona Kalyn M. , Rohli Robert V.
Published: November 2006

In previous research, Rohli et al. (2005) identified long‐term features of the northern hemispheric circumpolar vortex (NHCPV) in January. This research provides a seasonal analysis using December and February to augment the previously analyzed January data in representing winter, along with April, July, and October data to represent spring, summer, and autumn, respectively. A representative 500 hPa geopotential height contour was selected to delineate the NHCPV in each of the five months. The area, shape, and centroid of the monthly December, February, April, July, and October NHCPV are computed for 1959–2001 to supplement the previously identified January properties. These geometrical features of the NHCPV reveal relationships between hemispheric‐scale circulation and temperature anomalies throughout the year. A circularity ratio (Rohli et al., 2005) is used to characterize the shape of the hemispheric‐scale circulation. Results suggest that only October exhibit long‐term trends in either area or circularity, with July being the most variable month in area and October being the most variable month in circularity. Centroids tend to be skewed toward the Pacific basin, except in spring, but few systematic temporal shifts in centroid position were noted for any month. The NHCPV is correlated with atmospheric teleconnection patterns in several months. For example, as was the case for January (Rohli et al., 2005), the Arctic Oscillation (AO) is associated with the area of the December, February, and April NHCPV, while in December the circularity is positively correlated to the AO Index. Also, the Pacific‐North American index is correlated with the area of the December and February NHCPV and with the shape of the December and October NHCPV. Copyright © 2006 Royal Meteorological Society
Measuring and managing engagement in a cross‐cultural workforce: New insights for global companies
Authors: Sanchez Paul , McCauley Dan
Published: November 2006

Should a company take a global or local approach to building engagement in its worldwide workforce? Research by Mercer Human Resource Consulting finds that country norms for drivers of engagement, as well as for other employee perceptions about their work and their employers, differ noticeably from region to region—and not in ways that might be expected. But a core set of drivers is emerging globally. This should help multinational companies distinguish between global and local engagement issues, design a manageable global engagement strategy and initiatives, and tailor implementation to meet the needs and preferences of the local workforce. © 2006 Wiley Periodicals, Inc.
Critical events and next best activities in relationship marketing: Best practices beyond advanced analytics
Authors: Bartikowski Boris , Braunmüller Peter
Published: November 2006

Customer relationship management (CRM) systems are the backbone of effective marketing efforts. Yet some research has found that such systems can suffer failure rates as high as 75 percent, thus negating their value to their organizations. This interview explores both the promise and the problems of CRM applications. Because effective CRM implementation requires thorough organizational integration, particularly in the use of data warehousing techniques, both academic and managerial perspectives are brought to bear as the discussants detail the evolution of CRM applications and where their challenges lie. And they highlight some best practices of eventtriggered CRM uses. © 2006 Wiley Periodicals, Inc.
Stimulation of EP4 receptor enhanced bone consolidation during distraction osteogenesis
Authors: Chang Fei , Mishima Hajime , Ishii Tomoo , Yanai Takaji , Akaogi Hiroshi , Sakai Shinsuke , Yoshioka Tomokazu , Ochiai Naoyuki
Published: November 2006

The objective of this study was to confirm whether an agonist of prostaglandin E receptor subtype EP4 can enhance bone consolidation in distraction osteogenesis. A rat distraction osteogenesis model was generated. A unilateral external fixator was fixed to the left femur of the rats of this model after osteotomy. Seven days later, 0.25 mm/12 h or 0.5 mm/12 h elongation was performed for 2 weeks. A systemic administration of an EP4 receptor agonist (ONO 4819 · CD, 3, 10, 30 µg/kg) or normal saline by subcutaneous injection was also performed for 2 weeks. The animals were sacrificed 10, 14, 17, 21, and 42 days after the operation. Radiographic examination, histological examination, and measurements of bone mineral density (BMD) and distraction‐callus hardness were performed to qualitatively and quantitatively evaluate new bone formation. Twenty‐one days after the operation, the experimental group had a higher BMD and a higher distraction‐callus hardness than that of the control group. Forty‐two days after the operation, BMD was similar among all of the groups. But the hardness of the experimental groups increased more than that of the control group, so the statistical differences in distraction‐callus hardness became more distinct between the two groups, indicating an improved remodeling of the distraction callus. These findings are also supported by histological examination. Subcutaneous injection of an EP4 receptor agonist can promote bone formation and remodeling during distraction osteogenesis. ONO 4819 · CD might be a potential candidate for shortening the treatment time of distraction osteogenesis. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:221–229, 2007
Determination by Raman scattering of the nature of pigments in cultured freshwater pearls from the mollusk Hyriopsis cumingi
Authors: Karampelas S. , Fritsch E. , Mevellec J.‐Y. , Gauthier J.‐P. , Sklavounos S. , Soldatos T.
Published: November 2006

The nature of pigments in naturally colored pearls is still under discussion. For this study, Raman scattering measurements were obtained for 30 untreated freshwater cultured pearls from the mollusk Hyriopsis cumingi covering their typical range of colors. The originality of this work is that seven different excitation wavelengths (1064 nm, 676.44 nm, 647.14 nm, 514.53 nm, 487.98 nm, 457.94 nm, 363.80 nm) are used for the same samples at the highest possible resolution. All colored pearls show the two major Raman features of polyenic compounds assigned to double carbon–carbon (CC) – at about 1500 cm−1 – and single carbon–carbon (CC) – at about 1130 cm−1 – bond stretching mode, regardless of their specific hue. These peaks are not detected in the corresponding white pearls, and therefore seem directly related to the major cause of body color. Additionally, the exact position of CC stretching vibration shows that these compounds are not members of the carotenoid family. Moreover, some changes are observed in intensities, shape and positions of the two main characteristic polyenic peaks from one sample to the next. Similar changes are observed also using several excitation wavelengths for the same point of the same pearl. The exact position of CC stretching vibration of polyenic molecules depends strongly on the number of double bonds (N) contained in their polyenic chain. Hence, using a constrained decomposition of this band for different excitation wavelengths, up to nine different pigments may be detected in the same pearl. Their general chemical formula is R‐(CHCH)N‐R′ with N = 6–14. All our colored samples contained at least four pigments (N = 8–11). Different colors are explained by different mixtures, not by a simple change of pigment. The chemical nature of the chain ends is still unknown, because it cannot be detected with Raman scattering. However, it is possible that these polyenes are complexed with carbonate molecules of the nacre. Similar coloration mechanisms are found in products from other living organisms (e.g. parrots feathers). Moreover, it seems that a similar series of pigments is found in other pearls also, as well as in some marine animals living in similar environments (e.g. corals). Copyright © 2006 John Wiley & Sons, Ltd.