bluuebunny/crossref_metadata_2025 huggingface dataset:
A multicenter, randomized clinical trial comparing zoledronic acid versus observation in patients with asymptomatic myeloma
Authors: Musto Pellegrino , Petrucci Maria Teresa , Bringhen Sara , Guglielmelli Tommasina , Caravita Tommaso , Bongarzoni Velia , Andriani Alessandro , D'Arena Giovanni , Balleari Enrico , Pietrantuono Giuseppe , Boccadoro Mario , Palumbo Antonio
Published: August 2008

BACKGROUND.

Bisphosphonates (BPs) are effective in the prevention and treatment of skeletal‐related events (SREs) in patients with symptomatic myeloma who are receiving chemotherapy. Recent data also suggest a possible antineoplastic activity of BPs. Few studies published to date have explored the role of BPs in patients with untreated, asymptomatic myeloma (AM). No data are available on the efficacy of zoledronic acid in these patients.

METHODS.

The authors conducted a prospective, multicenter, open‐label, phase 3, randomized trial comparing the administration of zoledronic acid versus simple observation in patients with AM. One‐hundred sixty‐three patients were enrolled and randomized (1:1) to receive zoledronic acid (n = 81 patients) or not to receive zoledronic acid (n = 82 patients) for 1 year at a dose of 4 mg monthly as a single, 15‐minute, intravenous infusion.

RESULTS.

After a median follow‐up of 64.7 person‐months, 44.4% of patients in the zoledronic acid group and 45.1% of the control group progressed to ‘symptomatic’ myeloma requiring chemotherapy (P = .9307). The median time to progression was 67 months and 59 months for the treatment and control groups, respectively (P = .8312). At progression, SREs were significantly lower in the zoledronic acid‐treated group (55.5%) than in the control group (78.3%; P = .041), whereas anemia, renal failure, and extramedullary disease were not statistically different. More frequent adverse events observed in the zoledronic acid‐treated group were asymptomatic hypocalcemia and fever. One patient developed reversible osteonecrosis of the jaw. No renal failure caused by zoledronic acid was reported.

CONCLUSIONS.

The monthly use of zoledronic acid for 1 year in patients with AM reduced the development of SREs at progression but did not influence the natural history of the disease. Cancer 2008. © 2008 American Cancer Society.
The midget‐parvocellular pathway of marmoset retina: A quantitative light microscopic study
Authors: Telkes Ildiko , Lee Sammy C.S. , Jusuf Patricia R. , Grünert Ulrike
Published: August 2008

The midget‐parvocellular pathway in foveal retina of primates shows a “private line” (one‐to‐one) connectivity with cone photoreceptors. The connectivity of this pathway outside the fovea is not well understood. Here, we studied the population of OFF midget bipolar cells across the retinae of marmoset monkeys (Callithrix jacchus) by using light microscopy. Cone pedicles were labeled with peanut agglutinin, OFF midget bipolar cells were labeled with antibodies against CD15, and midget ganglion cells were retrogradely labeled from the lateral geniculate nucleus and subsequently photofilled. Each midget bipolar cell contacts a single cone in foveal retina, but outside the fovea midget bipolar cells contact multiple cones: one to two cones at 1 mm (∼8 degrees); three to four cones at 3–4 mm (∼25 degrees); and five or more cones beyond 6 mm (>50 degrees). Throughout this eccentricity range, all medium (M) and long (L) wavelength sensitive cones make similar number of contacts with midget bipolar cells, but short wavelength sensitive (S) cones make little or no contact. By calculating the numerical convergence between midget bipolar and midget ganglion cells, we estimate that midget ganglion cells receive input from up to 25 cones at ∼5 degrees, and from more than 65 cones at ∼50 degrees. No obvious differences were seen between the retinae of animals with di‐ or trichromatic color vision. The finding that the one‐to‐one connectivity is restricted to the fovea predicts that in marmosets spectral mixing of M/L cone inputs will occur peripheral to 10 degrees of visual angle. J. Comp. Neurol. 510:539–549, 2008. © 2008 Wiley‐Liss, Inc.
FISH analysis in cell touch preparations and cytological specimens from formalin‐fixed fetal autopsies
Authors: Rivasi Francesco , Schirosi Laura , Bettelli Stefania , Bigiani Nazzarena , Curatola Carlo
Published: August 2008

Postmortem studies on still‐borns and miscarriages are important to define the sex and eventually the morphologic anomalies correlated to chromosomal aberrations. When the conditions for carrying out a cytogenetic study do not exist, these chromosomal alterations can be investigated by nucleic acid fluorescent in situ hybridization (FISH), which can be performed on interphase nuclei, usually on formalin‐fixed paraffin embedded tissues or on fresh cytological specimens. The objective of the present study is to prove whether this technique can be successfully applied to formalin‐fixed cell touch preparations and cytological specimens obtained from foetal autopsies. The study was carried out 12 abortions some of which were spontaneous and some of which were therapeutic. The materials were formalin‐fixed. Cell touch preparations and cytological specimens were obtained. The FISH was performed using X/Y probes (Vysis) and the Aneuvysion Kit (05J38‐030, Vysis), the probes being for chromosomes 13/21 and X/Y/18. To verify the reliability of the technique, the same reactions were also performed on fresh analogous materials. The slides were evaluable, and the probes hybridized to interphase nuclei showed distinct signals. All the samples were adequate for FISH analysis without any notable difference in the results. Moreover, it is technically possible to perform this analysis not only on fresh but particularly on formalin‐fixed cytological specimens. On the other hand, the use of this type of cytological samples, as compared to formalin‐fixed and paraffin embedded tissue sections, has the advantage of presenting intact, noncut nuclei with preserved cytomorphology, avoiding the problems of overlapping nuclei and making the identification of the real chromosomal arrangement easier. Diagn. Cytopathol. 2008;36:633–636. © 2008 Wiley‐Liss, Inc.
Antioxidant Pathways and One‐Electron Oxidation of Dopamine and Cysteine in Electrospray and On‐Line Electrochemistry Electrospray Ionization Mass Spectrometry
Authors: Mautjana Nare Alpheus , Estes Joshua , Eyler John R. , Brajter‐Toth Anna
Published: August 2008

Dopamine [DA]+ (m/z 154), DA dimer [2DA‐H]+ (m/z 307) and DA quinone [DAQ]+ (m/z 152) are detected in positive ion mode electrospray ionization mass spectrometry (ESI MS) of dopamine in 50/1/49 (vol%) water/acetic acid/methanol. H/D exchange experiments support a covalent structure of DA dimer. Thus, ESI of DA may involve 1e−, 1H+ oxidation processes followed by rapid radical dimerization. The DA quinone signal is low in ESI MS, which indicates a low efficiency of the 2e−, 2H+ oxidation reaction. On‐line electrochemistry ESI MS (EC/ESI MS) with low electrochemical cell voltage floated on high ES voltage increases electrospray current and improves sensitivity for DA. The DA quinone signal increases and DA dimer signal decreases. A new configuration of the ESI MS instrument with a cone‐shaped capillary inlet significantly enhanced sensitivity of ESI and EC/ESI MS measurements. A DA quinone‐cysteine adduct [DAQ+Cys]+ was detected in solutions of DA with cysteine (Cys). ESI MS and EC/ESI MS indicate formation of the DA quinone‐cysteine adduct by 1e− pathway. Oxidation pathways in ESI MS are relevant to biological reactivity of DA and Cys.
Sensitive Electrochemical Detection of Horseradish Peroxidase at Disposable Screen‐Printed Carbon Electrode
Authors: Lee Ai‐Cheng , Liu Guodong , Heng Chew‐Kiat , Tan Swee‐Ngin , Lim Tit‐Meng , Lin Yuehe
Published: August 2008

A rapid, simple and sensitive electrochemical assay of horseradish peroxidase (HRP) performed on disposable screen‐printed carbon electrode was developed. HRP activities were monitored by square‐wave voltammetric (SWV) measuring the electroactive enzymatic product in the presence of o‐aminophenol and hydrogen peroxide substrate solution. SWV analysis demonstrated a greater sensitivity and shorter analysis time than the widely used amperometric and differential‐pulsed voltammetric methods. The voltammetric characteristics of substrate and enzymatic product as well as the parameters of SWV analysis were optimized. Under optimized conditions, a linear response for HRP from 0.003 to 0.1 U/mL and a detection limit of 0.002 U/mL (1.25×10−15 mol in 25 μL) were obtained with a good precision (RSD=8%; n=6). This rapid and sensitive HRP assay with microliter‐assay volume could be readily integrated to portable devices and point‐of‐care (POC) diagnosis applications.
Eating disorders in ballet dancing students: Problems and risk factors
Authors: Toro Josep , Guerrero Marta , Sentis Joan , Castro Josefina , Puértolas Carles
Published: August 2008

Objective

To study the prevalence of symptoms of eating disorders and risk eating behaviours and the relationship between life at a dance school and the risk of developing an eating disorder (ED) in an adolescent population of Spanish dance students.

Methods

Questionnaires were used to assess attitudes to eating, cultural influences on the body shape model, eating disorders (DSM‐IV) and risk factors for eating disorders in 76 adolescent dance students (age 12–17 years) at the Barcelona Theatre Institute. Subjects were compared with a community sample of 453 female adolescents. To study the relationship between ED and characteristics of this particular school, an original questionnaire was administered to 105 students at the school aged from 12 to 21 years.

Results

The prevalence of eating disorders and several risk attitudes and behaviours were similar in the dance students and the female adolescents from the general population. Students at risk of eating disorders perceived greater pressure from coaches concerning eating, appearance, weight and artistic performance; they felt less satisfied with their weight and weighed themselves more often; they avoided performing so as not to exhibit their body in public, disliked comparing their body with their peers and believed that audiences paid a great deal of attention to their bodies. In contrast, Body Mass Index (BMI) had hardly any influence on these experiences. Depressive symptoms were associated almost exclusively with experience of stressors and aversive situations.

Conclusions

Dance school students do not necessarily present a greater risk of ED than other girls of the same age. The risk of ED may be associated with greater pressure from coaches, with attitudes related to the ED itself, or with depressive symptoms, rather than with the BMI. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association.
Bank‐collapse processes in a valley‐bottom gully, western Iowa
Authors: Thomas John T. , Iverson Neal R. , Burkart Michael R.
Published: August 2008

Widening and bank‐slope reduction of a valley‐bottom gully in western Iowa was correlated to increasing subsurface flow over a 36‐year period. To study bank collapse at this gully, we measured rainfall, air temperature, hydraulic head near the banks and bank movement nearly continuously over a 2‐year period. Styles of movement ranged from imperceptible creep to rapid slab collapses preceded by the formation of tension cracks parallel to the gully walls. Bank movement was commonly correlated to rainfall or snowmelt and associated head increases in the banks. If the banks are modelled as a two‐dimensional slab with an adjacent tension crack partly filled with water, measured heads were sufficient to cause bank failures through reduction of frictional support at the base of the slab. During winter months, air temperature variations across 0 °C were correlated with bank movement: during mildly subfreezing periods banks expanded, and most, but usually not all, of this movement was recovered during above‐freezing periods. This motion is attributed to frost heave followed by thawing. Deformation of the banks by heaving and thawing during winter may weaken them and prime them for failure during spring rains and snowmelt, when the frequency of mass‐wasting events is highest. Copyright © 2008 John Wiley and Sons, Ltd.
Turbulence fields in the lee of two‐dimensional transverse dunes simulated in a wind tunnel
Authors: Dong Zhibao , Qinan Guangqiang , Lu Ping , Luo Wanyin , Wang Hongtao
Published: August 2008

The turbulence field of airflow in the lee of a dune has significant impacts on dune dynamics and related processes. We used particle image velocimetry in a wind tunnel simulation to obtain detailed velocity measurements in the lee of two‐dimensional transverse dune models, then used the results to analyse their turbulence fields. The dune models used in this study had a single lee angle of 30°, and a total of six stoss angles: 3°, 5°, 10°, 15°, 20° and 25°. We used vorticity, turbulence intensity, Reynolds stress and turbulent kinetic energy to characterize the turbulence fields. These parameters were functions of stoss angle, wind velocity, distance from the dune crest and height above the ground surface. The stoss angles could generally be divided into two groups based on the profiles of mean velocity, turbulence and Reynolds stress. Stoss angles of 3° and 5° usually had similar profiles, and angles of 15°, 20° and 25° formed a second group with similar profiles. The profiles for the stoss angle of 10° were usually transitional and were intermediate between the two groups. Vorticity, Reynolds stress and turbulent kinetic energy increased monotonically with increasing free‐stream wind velocity, but their variations with respect to the stoss angle were complex. The stoss angles of 15° and 20° had the maximum values of these three parameters, thus these angles may have special significance in dune development given the characteristics of the mean velocity fields and turbulence fields they produce within the lee airflow. It is the streamwise velocity component and its turbulence that determine the surface shear stress. Copyright © 2008 John Wiley and Sons, Ltd.
Parallel implementation of a non‐hydrostatic model for free surface flows with semi‐Lagrangian advection treatment
Authors: Jankowski Jacek A.
Published: August 2008

The parallel implementation of an unstructured‐grid, three‐dimensional, semi‐implicit finite difference and finite volume model for the free surface Navier–Stokes equations (UnTRIM) is presented and discussed. The new developments are aimed to make the code available for high‐performance computing in order to address larger, complex problems in environmental free surface flows. The parallelization is based on the mesh partitioning method and message passing and has been achieved without negatively affecting any of the advantageous properties of the serial code, such as its robustness, accuracy and efficiency. The key issue is a new, autonomous parallel streamline backtracking algorithm, which allows using semi‐Lagrangian methods in decomposed meshes without compromising the scalability of the code. The implementation has been carefully verified not only with simple, abstract test cases illustrating the application domain of the code but also with advanced, high‐resolution models presently applied for research and engineering projects. The scheme performance and accuracy aspects are researched and discussed. Copyright © 2008 John Wiley & Sons, Ltd.
A viscous vortex particle method for deforming bodies with application to biolocomotion
Authors: Zhang Li Jeany , Eldredge Jeff D.
Published: August 2008

Bio‐inspired mechanics of locomotion generally consist of the interaction of flexible structures with the surrounding fluid to generate propulsive forces. In this work, we extend, for the first time, the viscous vortex particle method (VVPM) to continuously deforming two‐dimensional bodies. The VVPM is a high‐fidelity Navier–Stokes computational method that captures the fluid motion through evolution of vorticity‐bearing computational particles. The kinematics of the deforming body surface are accounted for via a surface integral in the Biot–Savart velocity. The spurious slip velocity in each time step is removed by computing an equivalent vortex sheet and allowing it to flux to adjacent particles; hence, no‐slip boundary conditions are enforced. Particles of both uniform and variable size are utilized, and their relative merits are considered. The placement of this method in the larger class of immersed boundary methods is explored. Validation of the method is carried out on the problem of a periodically deforming circular cylinder immersed in a stagnant fluid, for which an analytical solution exists when the deformations are small. We show that the computed vorticity and velocity of this motion are both in excellent agreement with the analytical solution. Finally, we explore the fluid dynamics of a simple fish‐like shape undergoing undulatory motion when immersed in a uniform free stream, to demonstrate the application of the method to investigations of biomorphic locomotion. Copyright © 2008 John Wiley & Sons, Ltd.
Human leukocyte antigen polymorphisms in italian primary biliary cirrhosis: A multicenter study of 664 patients and 1992 healthy controls
Authors: Invernizzi Pietro , Selmi Carlo , Poli Francesca , Frison Sara , Floreani Annarosa , Alvaro Domenico , Almasio Piero , Rosina Floriano , Marzioni Marco , Fabris Luca , Muratori Luigi , Qi Lihong , Seldin Michael F. , Gershwin Eric M. , Podda Mauro
Published: August 2008

Genetic factors are critical in determining susceptibility to primary biliary cirrhosis (PBC), but there has not been a clear association with human leukocyte antigen (HLA) genes. We performed a multicenter case-control study and analyzed HLA class II DRB1 associations using a large cohort of 664 well-defined cases of PBC and 1992 controls of Italian ancestry. Importantly, healthy controls were rigorously matched not only by age and sex, but also for the geographical origin of the proband four grandparents (Northern, Central, and Southern Italy). After correction for multiple testing, DRB1*08 [odds ratio (OR), 3.3; 95% confidence interval (CI), 2.4-4.5] and DRB1*02 (OR 0.9; 95% CI 0.8-1.2) were significantly associated with PBC, whereas alleles DRB1*11 (OR 0.4; 95% CI 0.3-0.4) and DRB1*13 (OR 0.7; 95% CI 0.6-0.9) were protective. When subjects were stratified according to their grandparental geographical origin, only the associations with DRB1*08 and DRB1*11 were common to all three areas. Associated DRB1 alleles were found only in a minority of patients, whereas an additive genetic model is supported by the gene dosage effect for DRB1*11 allele and the interaction of DRB1*11,*13, and *08. Lastly, no significant associations were detected between specific DRB1 alleles and relevant clinical features represented by the presence of cirrhosis or serum autoantibodies. In conclusion, we confirm the role for HLA to determine PBC susceptibility and suggest that the effect of HLA is limited to patient subgroups. We suggest that a large whole-genome approach is required to identify further genetic elements contributing to the loss of tolerance in this disease. (Hepatology 2008;48:1906-1912.)
Changes in neuropsychological functioning following treatment with risperidone, olanzapine, and conventional antipsychotic medications
Authors: Jerrell Jeanette M. , Ramirez Paul Michael
Published: August 2008

Objective

To compare changes in neuropsychological functioning over time among adults with schizophrenia treated with atypical and conventional antipsychotics, controlling for phenomenological changes, medication dosage, concomitant use of anticholinergic medications, and practice effects.

Methods

In a larger clinical trial, 108 patients diagnosed with schizophrenia or schizoaffective disorder were randomly assigned to medication groups (risperidone, olanzapine, or conventional medications), treated in an open‐label design, and monitored prospectively for 12 months using standard neuropsychological and symptomatology instruments.

Results

Significant differential effects were evident on the ability to maintain and rapidly shift mental set within a psychomotor task, with patients in the conventional medication group consistently making more errors over time until the 12‐month follow‐up, when the olanzapine group made significantly more errors. Significant differential effects were also evident on delayed memory, with patients receiving olanzapine improving more steadily over time until the 12‐month follow‐up, when patients in the conventional group were able to recall significantly more. Positive and negative symptomatology was a significant, inversely related covariate on most of the cognitive measures examined.

Conclusions

The atypical and conventional medications examined were not consistently differential enhancers of cognitive functioning on disparate cognitive functioning measures over time. Copyright © 2008 John Wiley & Sons, Ltd.
Thin‐film assembly of diethanolamine‐based lipidic material as potential gene carrier in mouse embryonic neural stem cells
Authors: Kusumoto Ken‐ichi , Yamashita Satoko , Nagata Takahiro , Ido Takeshi , Hamachi Itaru , Akao Tetsuyuki
Published: August 2008

Understanding of lipidic materials used for gene delivery system is essential for the effective design and development of potential applications in basic and therapeutic research. This study aimed to evaluate the biological activity of totally synthesized ditetradecylacetyldiethanolaminetrimethylammonium (TMA‐C2‐DEA‐C14) as gene carriers for neural stem cells. The transfer abilities were estimated by expressing green fluorescent protein (GFP) in mouse embryonic neural stem cells. Here, we demonstrate that lipidic assembly of TMA‐C2‐DEA‐C14, which was self‐organized by incubation in water for a month at 25°C, can provide an efficient gene delivery with low cytotoxicity (∼40% of GFP‐expressed neural stem cells). However, when dispersed by ultrasonication, TMA‐C2‐DEA‐C14 showed low effect (∼4%). Moreover, electron microscopic analysis showed that TMA‐C2‐DEA‐C14 assembly is characterized by thin‐film structures with polygonal shapes (∼2.7 μm), and after association with DNA, their structures dramatically changes to form liposome complexes that can effectively deliver DNA into the cellular cytoplasm of neural stem cells. Thus, TMA‐C2‐DEA‐C14 assembly identified in this study was determined to have an effective activity as gene carriers for primary neural stem cells. Our findings suggest that this approach can serve as a novel model for the development of lipidic materials on nonviral gene delivery system. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Covalent surface modification of a titanium alloy with a phosphorylcholine‐containing copolymer for reduced thrombogenicity in cardiovascular devices
Authors: Ye Sang‐Ho , Johnson Carl A. , Woolley Joshua R. , Snyder Trevor A. , Gamble Lara J. , Wagner William R.
Published: August 2008

Our objective was to develop a surface modification strategy for a titanium alloy (TiAl6V4) to provide thromboresistance for surfaces in rigorous blood‐contacting cardiovascular applications, such as that found in ventricular assist devices. We hypothesized that this could be accomplished by the covalent attachment of a phospholipid polymer, poly(2‐methacryloyloxyethylphosphorylcholine (MPC)‐co‐methacryl acid) (PMA). TiAl6V4 was H2O plasma treated by radio frequency glow discharge, silanated with 3‐aminopropyltriethoxysilane (APS), and ammonia plasma treated to increase surface reactivity. The TiAl6V4 surface was then modified with PMA via a condensation reaction between the amino groups on the TiAl6V4 surface and the carboxyl groups on PMA. The surface composition was verified by X‐ray photoelectron spectroscopy, confirming successful modification of the TiAl6V4 surfaces with APS and PMA as evidenced by increased Si and P. Plasma treatments with H2O and ammonia were effective at further increasing the surface reactivity of TiAl6V4 as evidenced by increased surface PMA. The adsorption of ovine fibrinogen onto PMA‐modified surfaces was reduced relative to unmodified surfaces, and in vitro ovine blood contact through a rocking test revealed marked reductions in platelet deposition and bulk phase platelet activation relative to unmodified TiAl6V4 and polystyrene controls. The results indicate that the PMA‐modification scheme for TiAl6V4 surfaces offers a potential pathway to improve the thromboresistance of the blood‐contacting surfaces of cardiovascular devices. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Tendon bone healing can be enhanced by demineralized bone matrix: A functional and histological study
Authors: Sundar Siva , Pendegrass Catherine J. , Blunn Gordon W.
Published: August 2008

Rotator cuff repair surgery has high failure rates, with tendon reattachment to bone remaining a challenging clinical problem. Increasing the integrity of the healing tendon‐bone interface has been attempted by adopting a number of different augmentation strategies. Because of chondrogenic and osteogenic properties we hypothesise that demineralized bone matrix (DBM) augmentation of a healing tendon‐bone interface will result in improved function, and a morphology that more closely resembles that of a normal enthesis, compared with nonaugmented controls in an ovine patellar tendon model. The right patellar tendon was detached from its insertion and reattached to an osteotomized bone bed using suture anchors. Two groups were analyzed, the control group (without augmentation) and the DBM group (DBM interposed between the tendon and bone). Animals were sacrificed at 12 weeks. Force plate, mechanical, and histomorphometric analyses were performed. Tendon repairs failed at a rate of 33 and 0% for the control and DBM groups, respectively. DBM augmentation resulted in significantly improved functional weight bearing and increased amounts of fibrocartilage and mineralized fibrocartilage. This study shows that DBM enhances tendon‐bone healing and may reduce the high failure rates associated with rotator cuff repair clinically. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
In vivo severe corrosion and hydrogen embrittlement of retrieved modular body titanium alloy hip‐implants
Authors: Rodrigues Danieli C. , Urban Robert M. , Jacobs Joshua J. , Gilbert Jeremy L.
Published: August 2008

Titanium alloys are widely used in total‐joint replacements due to a combination of outstanding mechanical properties, biocompatibility, passivity, and corrosion resistance. Nevertheless, retrieval studies have pointed out that these materials can be subjected to localized or general corrosion in modular interfaces when mechanical abrasion of the oxide film (fretting) occurs. Modularity adds large crevice environments, which are subject to micromotion between contacting interfaces and differential aeration of the surface. Titanium alloys are also known to be susceptible to hydrogen absorption, which can induce precipitation of hydrides and subsequent brittle failure. In this work, the surface of three designs of retrieved hip‐implants with Ti‐6Al‐4V/Ti‐6Al‐4V modular taper interfaces in the stem were investigated for evidence of severe corrosion and precipitation of brittle hydrides during fretting‐crevice corrosion in the modular connections. The devices were retrieved from patients and studied by means of scanning electron microscopy (SEM), X‐ray diffraction (XRD), and chemical analysis. The surface qualitative investigation revealed severe corrosion attack in the mating interfaces with evidence of etching, pitting, delamination, and surface cracking. In vivo hydrogen embrittlement was shown to be a mechanism of degradation in modular connections resulting from electrochemical reactions induced in the crevice environment of the tapers during fretting‐crevice corrosion. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
The mechanism of double proton transfer in dimers of uracil and 2‐thiouracil—The reaction force perspective
Authors: Lamsabhi Al Mokhtar , Mó Otilia , Gutiérrez‐Oliva Soledad , Pérez Patricia , Toro‐Labbé Alejandro , Yáñez Manuel
Published: August 2008

The intermolecular double proton transfer in dimers of uracil and 2‐thiouracil is studied through density functional theory calculations. The reaction force framework provides the basis for characterizing the mechanism that in all cases has been associated to a dynamic balance between polarization and charge transfer effects. It has been found that the barriers for proton transfer depend upon the nature of the acceptor atoms and its position within the seminal monomer. Actually, the change in the nature of the hydrogen bonds connecting the two monomers along the reaction coordinate may favor or disfavor the double‐proton transfer. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Comparison of glycolysis and oxidative phosphorylation as energy sources for mammalian sperm motility, using the combination of fluorescence imaging, laser tweezers, and real‐time automated tracking and trapping
Authors: Nascimento Jaclyn M. , Shi Linda Z. , Tam James , Chandsawangbhuwana Charlie , Durrant Barbara , Botvinick Elliot L. , Berns Michael W.
Published: August 2008

The combination of laser tweezers, fluorescent imaging, and real‐time automated tracking and trapping (RATTS) can measure sperm swimming speed and swimming force simultaneously with mitochondrial membrane potential (MMP). This approach is used to study the roles of two sources of ATP in sperm motility: oxidative phosphorylation, which occurs in the mitochondria located in the sperm midpiece and glycolysis, which occurs along the length of the sperm tail (flagellum). The relationships between (a) swimming speed and MMP and (b) swimming force and MMP are studied in dog and human sperm. The effects of glucose, oxidative phosphorylation inhibitors and glycolytic inhibitors on human sperm motility are examined. The results indicate that oxidative phosphorylation does contribute some ATP for human sperm motility, but not enough to sustain high motility. The glycolytic pathway is shown to be a primary source of energy for human sperm motility. J. Cell. Physiol. 217: 745–751, 2008. © 2008 Wiley‐Liss, Inc.
Phage display screening for peptidic chitinase inhibitors
Authors: Petter Cordula , Scholz Christa , Wessner Helga , Hansen Gerd , Henklein Peter , Watanabe Takeshi , Höhne Wolfgang
Published: August 2008

A phage display library with disulfide‐cyclized peptides was screened for peptides binding to chitinases from Serratia marcescens. One of those peptides was found to efficiently inhibit chitinase A and two others were inhibitors of chitinase B. Complete substitutional analysis of all three peptides using cellulose‐bound peptide spot synthesis revealed key interaction positions and allowed optimization of the chitinase B inhibitory peptides towards higher affinity, with inhibitory constants in the lower nanomolar range. Inhibition by all peptides proved to be competitive and highly specific for the chitinase used to select them, as shown with a series of chitinases from different organisms. Copyright © 2008 John Wiley & Sons, Ltd.
Transcriptional profile of primary astrocytes expressing ALS‐linked mutant SOD1
Authors: Vargas Marcelo R. , Pehar Mariana , Díaz‐Amarilla Pablo J. , Beckman Joseph S. , Barbeito Luis
Published: August 2008

Amyotrophic lateral sclerosis (ALS) is caused by the progressive degeneration of motor neurons. Mutations in the Cu/Zn superoxide dismutase (SOD1) are found in approximately 20% of patients with familial ALS. Mutant SOD1 causes motor neuron death through an acquired toxic property. Although the molecular mechanism underlying this toxic gain‐of‐function remains unknown, evidence support the role of mutant SOD1 expression in nonneuronal cells in shaping motor neuron degeneration. We have previously found that in contrast to nontransgenic cells, SOD1G93A‐expressing astrocytes induced apoptosis of cocultured motor neurons. This prompted us to investigate whether the effect on motor neuron survival was related to a change in the gene expression profile. Through high‐density oligonucleotide microarrays, we found changes in the expression of genes involved in transcription, signaling, cell proliferation, extracellular matrix synthesis, response to stress, and steroid and lipid metabolism. The most up‐regulated gene was decorin (Dcn), a small multifunctional extracellular proteoglycan. Down‐regulated genes included the insulin‐like growth factor‐1 receptor (Igf‐1r) and the RNA binding protein ROD1. Rod1 was also found down‐regulated in purified motor neurons expressing SOD1G93A. Changes in the expression of Dcn, Igf‐1r, and Rod1 were found in the spinal cord of asymptomatic animals, suggesting these changes occur before overt neuronal degeneration and potentially influence astrocyte–motor neuron interaction in the course of the disease. The astrocyte‐specific gene expression profile might contribute to the identification of possible candidates for cell type‐specific therapies in ALS. © 2008 Wiley‐Liss, Inc.
Intracerebral transplantation of neural stem cells combined with trehalose ingestion alleviates pathology in a mouse model of Huntington's disease
Authors: Yang Chia‐Ron , Yu Robert K.
Published: August 2008

The present investigation examined the neuroprotective benefits for combined trehalose administration with C17.2 neural stem cell transplantation in a transgenic mouse model of Huntington's disease (HD), R6/2. C17.2 neural stem cells have the potential of differentiating into a neuronal phenotype in vitro and have been shown to be effective in the treatment of a variety of lysosomal lipid storage disorders in the nervous system. In this study, we transplanted these cells into the lateral ventricle of R6/2 transgenic mice in order to examine the efficacy of using these cells for correcting the accumulated polyglutamine storage materials in HD. To improve efficacy, animals were fed with a diet rich in trehalose, which has been shown to be beneficial to retard aggregate formation. The combined treatment strategy not only decreased ubiquitin‐positive aggregation in striatum, alleviated polyglutamine aggregation formation, and reduced striatal volume, but also extended life span in the R6/2 animal model. Behavioral evaluation showed that the combination treatment improved motor function. Statistical analysis revealed that the combination treatment was more effective than treatment with trehalose alone on the basis of the above biochemical and behavioral criteria. This study provides a strong a basis for further developing an effective therapeutic strategy for HD. © 2008 Wiley‐Liss, Inc.
Evidence for disruption of sphingolipid metabolism in schizophrenia
Authors: Narayan Sujatha , Head Steven R. , Gilmartin Timothy J. , Dean Brian , Thomas Elizabeth A.
Published: August 2008

As the field of glycobiology grows, important roles for glycolipids and glycoproteins in neurological disorders are being increasingly appreciated. However, few studies have explored the involvement of these molecules in the pathology of psychiatric illnesses. We investigated molecular differences related to glycobiology in subjects with schizophrenia by analyzing gene expression profiles using a focused glycogene chip, a custom‐designed oligonucleotide array containing genes encoding proteins related to glycobiology, including glycosyltransferases, carbohydrate‐binding proteins, proteoglycans, and adhesion molecules. We measured expression profiles in prefrontal cortical (BA46) samples from schizophrenic subjects and matched controls. We find differential expression of genes particularly related to glycosphingolipid/sphingolipid metabolism and N‐ and O‐linked glycan biosynthesis in subjects with schizophrenia. Expression decreases of seven genes associated with these pathways, UGT8, SGPP1, GALC, B4GALT6, SPTLC2, ASAH1, and GAL3ST1, were validated by quantitative PCR in schizophrenic subjects with short‐term illness. Only one of these genes, SPTLC2, showed differential expression in chronic schizophrenic subjects, although an increase in expression was observed. Covariate analysis showed that the expression of five of these genes was significantly positively correlated with age in schizophrenic, but not control, subjects. These changing patterns of expression could represent an adaptive response to pathology with disease progression or a compensatory effect of antipsychotic medication, although no significant correlations between gene expression levels and drug doses were observed. Disruption of sphingolipid metabolism early in illness could result in widespread downstream effects encompassing diverse pathological deficits already described in schizophrenia, especially those involving myelination and oligodendrocyte function; hence, this system may represent an important link in schizophrenia pathology. © 2008 Wiley‐Liss, Inc.
Effect of plant cultivation methods on content of major and trace elements in foodstuffs and retention in rats
Authors: Kristensen Mette , Østergaard Lars F , Halekoh Ulrich , Jørgensen Henry , Lauridsen Charlotte , Brandt Kirsten , Bügel Susanne
Published: August 2008

BACKGROUND: Many consumers perceive organic foods as more nutritious than conventional foods. However, the existing evidence is insufficient to support or refute this belief. The purpose of the present study was to investigate the effect of three different model cultivation systems on selected major and trace element contents of dried foodstuffs (carrots, kale, peas, potatoes and apples) grown in two consecutive years, as well as mineral retention determined in 36 rats (second generation in a multi‐generation study) fed diets based on these foodstuffs from one year.

RESULTS: Overall, there was no evident trend towards differences in element content of foodstuffs or diets due to the use of different cultivation systems, and differences between harvest years exceeded those seen between cultivation methods. Also, no significant differences in the retention of elements in rats fed diets derived from different cultivation systems were seen, since higher intake resulted in correspondingly higher excretion.

CONCLUSION: This study does not support the belief that organically grown foodstuffs generally contain more major and trace elements than conventionally grown foodstuffs, nor does there appear to be an effect on the bioavailability of major and trace minerals in rats. Copyright © 2008 Society of Chemical Industry
Timing of sentinel lymph node biopsy in patients receiving neoadjuvant chemotherapy for breast cancer
Authors: Papa Moshe Zvi , Zippel Douglas , Kaufman Bella , Shimon‐Paluch Shani , Yosepovich Ady , Oberman Bernice , Sadetzki Siegal
Published: August 2008

Objective

To address optimal timing of sentinel lymph node biopsy (SLNB) in breast cancer patients undergoing neoadjuvant treatment.

Methods

The study population included 117 patients with locally advanced cancer with clinically negative nodes treated with primary chemotherapy. Group 1 underwent SLNB and completion axillary lymph node dissection (ALND) in conjunction with lumpectomy/mastectomy, after neoadjuvant treatment (n = 31). Group 2 underwent SLNB followed by neoadjuvant therapy and subsequently surgery and completion of ALNDs (n = 58). Group 3 was treated using the same sequence as group 2, however, completion ALND was performed only for patients with positive sentinel lymph nodes (SLNs) (n = 28).

Results

SLN identification was lowest in group 1 compared to groups 2 and 3 (87% and 98.8% respectively; P = <0.05). The highest false negative rate was in group 1 (15.8% compared with 0% in group 2).

Conclusion

Neoadjuvant treatment lowers the SLN identification rate, possibly due to fibrosis within the axilla, and increases the false negative rate due to downstaging. SLN biopsy prior to chemotherapy could give a more accurate evaluation of axillary status, unaffected by any previous therapeutic intervention. J. Surg. Oncol. © 2008 Wiley‐Liss, Inc.
Oligonucleotide Nanostructured Surfaces: Effect on Escherichia coli Curli Expression
Authors: Cottenye Nicolas , Teixeira Francisco , Ponche Arnaud , Reiter Günter , Anselme Karine , Meier Wolfgang , Ploux Lydie , Vebert‐Nardin Corinne
Published: August 2008

Oligonucleotide model surfaces allowing independent variation of topography and chemical composition were designed to study the adhesion and biofilm growth of E.coli. Surfaces were produced by covalent binding of oligonucleotides and immobilization of nucleotide‐based vesicles. Their properties were confirmed through a combination of fluorescence microscopy, XPS, ellipsometry, AFM and wettability studies at each step of the process. These surfaces were then used to study the response of three different strains of E.coli quantified in a static biofilm growth mode. This study led to convincing evidence that oligonucleotide‐modified surfaces, independent of the topographical feature used in this study, enhanced curli expression without an increase in the number of adherent bacteria.

magnified image
Cellular Adhesion, Proliferation and Viability on Conducting Polymer Substrates
Authors: del Valle Luis J. , Estrany Francesc , Armelin Elaine , Oliver Ramón , Alemán Carlos
Published: August 2008

This work reports a comprehensive study about cell adhesion and proliferation on the surface of different electroactive substrates formed by π‐conjugated polymers. Biological assays were performed considering four different cellular lines: two epithelial and two fibroblasts. On the other hand, the electroactivity of the three conducting systems was determined in physiological conditions. Results indicate that the three substrates behave as a cellular matrix, even though compatibility with cells is larger for PPy and the 3‐layered system. Furthermore, the three polymeric systems are electro‐compatible with the cellular monolayers.

magnified image
Corrosion mechanisms in the wood industry, especially caused by tannins
Authors: Winkelmann H. , Badisch E. , Roy M. , Danninger H.
Published: August 2008

In order to improve the lifetime of cutting knives in the wood processing industry, a study has been undertaken to find out which wear process is primarily responsible for the reduction of the lifetime of steel blades. The examination of damaged surfaces of the cutting tools reveals mechanical damage at the cutting edges on one hand, but on the other hand pitting corrosion can be detected. It turned out that the corrosion impact reduces the lifetime of the cutting tools more than the mechanical loading, because a mechanically damaged steel blade can easily be repaired through grinding. But once the blade is subjected to pitting corrosion, it becomes useless because whenever the blade is reground, new holes due to pitting corrosion come to the surface again. Further investigations showed that the corrosiveness of different wood types is responsible for a major part of the damage, and that different woods have a different corrosive impact. One important goal of the present investigation is to learn more about the corrosive agents of different woods. It is revealed that tannin, a water‐soluble acid, which can be found in all woods in different concentrations, is responsible for the main part of the corrosive attack. In view of the above, the corrosion mechanism of steel blades caused by tannin is analyzed. During the cutting processes in the industry the blade temperature is increased. Thus, it is aimed to evaluate the influence of higher temperatures on tannin and the pH value of the acid. It is also revealed that the additional mechanical stress has an important influence on the corrosion process. The investigation could satisfactorily show the lowering of the pH value of tannin acid at higher temperature, which leads to increased corrosion. It is also revealed that the additional mechanical stress causes off stripping of tannin–Fe complexes from the steel surface, there the steel was not able to build a protective layer yet. That also leads to a further increase in corrosion.
Structure and Mechanical Properties of Poly(lactic acid) Filled with (Starch nanocrystal)‐graft‐poly(ε‐caprolactone)
Authors: Yu Jiahui , Ai Fujin , Dufresne Alain , Gao Shanjun , Huang Jin , Chang Peter R.
Published: August 2008

Poly(ε‐caprolactone) (PCL) was grafted to the surface of starch nanocrystals (StN) via microwave‐assisted ROP. The resultant nanoparticles were then incorporated into a poly(lactic acid) matrix to produce fully‐biodegradable nanocomposites with good mechanical properties. A loading level of 5 wt.‐% StN‐g‐PCL resulted in simultaneous enhancements of strength and elongation. The StN‐g‐PCL self‐aggregated as rubbery microparticles to enhance the elongation by ca. 10‐fold over that of neat PLA. Meanwhile, the grafted PCL chains were miscible with PLA and formed a stress‐transferring interface to the StN, providing a reinforcing function.

magnified image
Hydrated Clay for Catalyst Removal in Copper Mediated Atom Transfer Radical Polymerization
Authors: Munirasu Selvaraj , Deshpande Ashwini , Baskaran Durairaj
Published: August 2008

A simple method has been described to remove catalyst from the copper mediated atom transfer radical polymerization (ATRP) of benzyl methacrylate and methyl methacrylate in anisole at 25 °C using hydrated natural clay (sodium montmorillonite, Na‐clay). The method consists of (1) addition of hydrated clay (CuI/clay ≈ 5 wt.‐%) either during or after the polymerization, (2) oxidation of catalyst complex by exposing the terminated reaction mixture in air, and (3) filtration to obtain catalyst free polymer solution. A strong coordination of CuBr‐ligand complex onto hydrated clay (10 wt.‐% < H2O/clay < 30 wt.‐%) upon oxidation resulted in polymers with no or insignificant residual catalyst (<1.74 ppm), as determined by UV‐vis and atomic absorption spectroscopy. The recovered clay exhibited expanded intercalary layers and absence of polymer within it.

magnified image
Micellization of a Siloxane‐Based Segmented Copolymer in Organic Solvents and its Use as a Tool for Metal Complex Nanoparticles
Authors: Racles Carmen , Cazacu Maria , Ioanid Aurelia , Vlad Angelica
Published: August 2008

The micellization of a polysiloxane‐ketimine has been studied in solvents of different polarity, i.e., dimethylformamide (DMF) and toluene. The critical micelle concentration was determined from surface tension measurements ‐in DMF‐, and from viscosity variation with concentration. Metal complex nanoparticles have been synthesized from this macromolecular ligand in DMF and in toluene, using the formed micelles as templates. Spectroscopic data (IR and UV‐vis) confirmed the metal complexation. TEM observations revealed the formation of nanoparticles with different morphologies, which were consistent with the assumed conformation of the ligand in solutions of the two selective solvents.

magnified image
Reductive Formation of Isospecific Ti Dinuclear Species on a MgCl2 (110) Surface in Heterogeneous Ziegler‐Natta Catalysts
Authors: Taniike Toshiaki , Terano Minoru
Published: August 2008

Dinucleation of TiCl4 on the MgCl2 (100) surface has been conventionally believed as the origin of the stereospecificity of heterogeneous Ziegler‐Natta catalysts for propylene polymerization, while the MgCl2 (110) surface has been regarded as non‐stereoselective in the absence of organic donors. Based on periodic density functional calculations, we propose a new isospecific Ti dinuclear species on the MgCl2 (110) surface, which is formed as a result of reduction of Ti from 4+ to 3+. The new species closely resembles the dinuclear species on the (100) surface, but two Ti ions are obliquely stacked along the (110) surface through Cl bridges. The results address the importance of the reduction and re‐distribution of surface Ti species after contacting with cocatalysts in considering the origin of the stereospecificity.

magnified image