bluuebunny/crossref_metadata_2025 huggingface dataset:
“Aging Out” of Violence: The Multiple Faces of Intimate Violence Over the Life Span
Authors: Band-Winterstein Tova , Eisikovits Zvi
Published: December 2008

In this article, we explore how continuous intimate partner violence is experienced in old age and how age and violence interact and change throughout the life span. This is a qualitative study based on a phenomenological perspective focusing on the lived experiences of the elderly who have dwelled in domestic violence most of their lives. The sample consisted of 40 informants. In-depth, semistructured interviews were performed. Content analysis of the interviews yielded four clusters of living in violence over time: (a) The arena of violence is alive and active, (b) violence is in the air, (c) more of the same but differently, and (d) violence through illness to the very end. These clusters are discussed and their implications for practice are suggested.
Review Article: Review of the Literature on Temporal Resolution in Listeners With Cochlear Hearing Impairment: A Critical Assessment of the Role of Suprathreshold Deficits
Authors: Reed Charlotte M. , Braida Louis D. , Zurek Patrick M.
Published: December 2008

A critical review of studies of temporal resolution in listeners with cochlear hearing impairment is presented with the aim of assessing evidence for suprathreshold deficits. Particular attention is paid to the roles of variables—such as stimulus audibility, overall stimulus level, and participant's age—which may complicate the interpretation of experimental findings in comparing the performance of hearing-impaired (HI) and normal-hearing (NH) listeners. On certain temporal tasks (e.g., gap detection), the performance of HI listeners appears to be degraded relative to that of NH listeners when compared at equal SPL (sound pressure level). For other temporal tasks (e.g., forward masking), HI performance is degraded relative to that of NH listeners when compared at equal sensation level. A relatively small group of studies exists, however, in which the effects of stimulus audibility and level (and occasionally participant's age) have been controlled through the use of noise-masked simulation of hearing loss in NH listeners. For some temporal tasks (including gap-detection, gap-duration discrimination, and detection of brief tones in modulated noise), the performance of HI listeners is well reproduced in the results of noise-masked NH listeners. For other tasks (i.e., temporal integration), noise-masked hearing-loss simulations do not reproduce the results of HI listeners. In three additional areas of temporal processing (duration discrimination, detection of temporal modulation in noise, and various temporal-masking paradigms), further studies employing control of stimulus audibility and level, as well as age, are necessary for a more complete understanding of the role of suprathreshold deficits in the temporal-processing abilities of HI listeners.
Partisan Strength and Nonpartisanship Among Asian Americans
Authors: Nguyen N. Kim , Garand James C.
Published: December 2008

Relatively little is known about partisan identification among immigrant-dominated ethnic groups in the United States. In this article we build on the work of Lien, Conway, and Wong (2004) to explore patterns of partisan strength and nonpartisanship among Asian Americans. We note that more than one third of Asian Americans do not identify themselves on the standard seven-point partisan identification scale, indicating that they either have no party attachment (denoted no-party nonpartisans) or are not sure of their partisanship (denoted unsure nonpartisans). Using data from the 2000-2001 Pilot National Asian American Political Survey, we estimate separate models of (a) partisan acquisition (i.e., partisan vs. nonpartisan), (b) strength of partisanship, and (c) type of nonpartisanship. As expected, we find significant differences in this Asian American sample between partisans and nonpartisans and among strong partisans, weak or independent-leaning partisans, and pure independents. In our nonpartisanship model, we also find discernible differences among pure independents, no-party nonpartisans, and unsure nonpartisans. Our findings address questions about how one should test models of party strength in Asian American samples, particularly given the relatively large percentage of nonpartisans among Asian Americans in comparison to samples drawn from the general population.
On the Relative Contribution of the Paretic Leg to the Control of Posture After Stroke
Authors: Roerdink Melvyn , Geurts Alexander C. H. , de Haart Mirjam , Beek Peter J.
Published: December 2008

Background. Reduced postural steadiness and asymmetry of weight bearing are characteristic for posture after stroke. Objective. To examine the relative contribution of each leg to postural control in a cohort of 33 stroke patients at 5 stages during 3 months of inpatient rehabilitation, while taking clinical scores of sensory and motor impairments of the paretic leg into account. Methods. Participants were instructed to stand as symmetrically as possible under both sensory and cognitive manipulations, while a dual-plate force platform was used to assess the contribution of each leg to postural control, quantified by the amplitude, velocity, and regularity of recorded center-of-pressure trajectories. A greater contribution of the nonparetic leg was expected, particularly in patients with ankle clonus, disturbed sensibility, and lack of selective muscle control on the paretic side. Results. With follow-up assessments, weight-bearing asymmetry and postural steadiness improved. Patients strongly relied on visual information. When attention was distracted by having the patients perform an arithmetic task, weight-bearing asymmetry increased, suggesting that symmetric weight bearing was attention demanding. Patients with severe motor impairments of the paretic leg showed greater static (weight-bearing) and dynamic (lateralized control) asymmetries than patients with limited motor impairments, whereas postural steadiness did not differ between these subgroups. Disturbed sensation did not affect weight-bearing asymmetry, postural steadiness, or lateralized control. Conclusion. Patients with severe motor impairments of the paretic leg employ an effective compensatory strategy consisting of asymmetric weight bearing and lateralized control.
Bilateral Upper Limb Training With Functional Electric Stimulation in Patients With Chronic Stroke
Authors: Chan Marko Ka-leung , Tong Raymond Kai-yu , Chung Kenneth Yiu-kwan
Published: December 2008

Background. The recovery rate of upper limb function after stroke is poor when compared with independent walking. Therefore, effective methods are warranted for upper limb rehabilitation. Objective. The aim of this study was to investigate the effectiveness of functional electric stimulation (FES) with bilateral activities training on upper limb function. Methods. This study was a double-blinded randomized controlled trial. Twenty patients were recruited 6 months after the onset of stroke and completed 15 training sessions. Participants were randomly assigned to the FES group or to the control group. Each session consisted of stretching activities (10 minutes), FES with bilateral tasks (20 minutes), and occupational therapy treatment (60 minutes). The participants used a self-trigger mechanism, with an accelerometer as a motion detector, for generating an electric stimulation pattern that was synchronized with the bilateral upper limb activities during the training. The participants in the control group received the same duration of stretching and occupational therapy training except that they just received placebo stimulation with the bilateral tasks. The outcome measures included Functional Test for the Hemiplegic Upper Extremity (FTHUE), Fugl—Meyer Assessment (FMA), grip power, forward reaching distance, active range of motion of wrist extension, Functional Independence Measure, and Modified Ashworth Scale. Results. At baseline comparison, there was no significant difference in both groups. After 15 training sessions, the FES group had significant improvement in FMA ( P = .039), FTHUE ( P = .001), and active range of motion of wrist extension ( P = .020) when compared with the control group. Conclusions. Bilateral upper limb training with FES could be an effective method for upper limb rehabilitation of stroke patients after 15 training sessions.
Peripheral blood lymphocytes genetically modified to express the self/tumor antigen MAGE-A3 induce antitumor immune responses in cancer patients
Authors: Fontana Raffaella , Bregni Marco , Cipponi Arcadi , Raccosta Laura , Rainelli Cristina , Maggioni Daniela , Lunghi Francesca , Ciceri Fabio , Mukenge Sylvain , Doglioni Claudio , Colau Didier , Coulie Pierre G. , Bordignon Claudio , Traversari Catia , Russo Vincenzo
Published: December 2008

Dendritic cell (DC) targeting in vivo has recently been shown to confer strong and protective cytotoxic T lymphocyte (CTL)–based immunity in tumor murine models. Our group has recently demonstrated in preclinical models that the infusion of genetically modified lymphocytes (GMLs) expressing the self/tumor antigen TRP-2 is able to elicit functional TRP-2–specific effectors with antitumor activity by targeting DCs in vivo. Here we have analyzed vaccine- and tumor-specific immune responses of 10 melanoma patients treated with autologous GMLs expressing the cancer germline gene MAGE-A3. Three of 10 patients treated with MAGE-A3–GML showed an increase of circulating anti–MAGE-A3 T cells, and developed skin delayed-type hypersensitivity to MAGE-A3. Interestingly, in 2 of these patients, with progressive and measurable tumors at study entry, anti–MAGE-A3 T cells were detected not only in the blood but also within tumors resected after vaccination. These results demonstrate that the infusion of MAGE-A3–GML elicits antitumor T cells, which are capable of trafficking to inflamed tissues and of infiltrating tumors. Clinical studies on a larger group of patients are needed to evaluate the clinical efficacy of such a strategy.
Cotreatment with BCL-2 antagonist sensitizes cutaneous T-cell lymphoma to lethal action of HDAC7-Nur77–based mechanism
Authors: Chen Jianguang , Fiskus Warren , Eaton Kelly , Fernandez Pravina , Wang Yongchao , Rao Rekha , Lee Pearl , Joshi Rajeshree , Yang Yonghua , Kolhe Ravindra , Balusu Ramesh , Chappa Prasanthi , Natarajan Kavita , Jillella Anand , Atadja Peter , Bhalla Kapil N.
Published: December 2008

Pan-histone deacetylase inhibitors, for example, vorinostat and panobinostat (LBH589; Novartis Pharmaceuticals, East Hanover, NJ), have shown clinical efficacy against advanced cutaneous T-cell lymphoma (CTCL). However, the molecular basis of this activity remains unclear. HDAC7, a class IIA histone deacetylase (HDAC), is overexpressed in thymocytes, where it represses expression of the proapoptotic nuclear orphan receptor Nur77. Here, we demonstrate that treatment with panobinostat rapidly inhibits the in vitro and intracellular activity, as well as the mRNA and protein levels of HDAC7, and induces expression and translocation of Nur77 to the mitochondria. There, Nur77 converts death resistance protein Bcl-2 into a killer protein, promoting cell death of cultured and patient-derived human CTCL cells. Treatment with panobinostat improved survival of athymic nude mice implanted with human CTCL cells. Ectopic expression of Nur77 induced apoptosis and sensitized HH cells to panobinostat, whereas combined knockdown of Nur77 and its family member Nor1 was necessary to inhibit panobinostat-induced apoptosis of CTCL cells. Cotreatment with the Bcl-2/Bcl-xL antagonist ABT-737 decreased resistance and synergistically induced apoptosis of human CTCL cells. These findings mechanistically implicate HDAC7 and Nur77 in sensitizing human CTCL cells to panobinostat as well as suggest that cotreatment with an anti–Bcl-2 agent would augment the anti-CTCL activity of panobinostat.
microRNA expression in the biology, prognosis, and therapy of Waldenström macroglobulinemia
Authors: Roccaro Aldo M. , Sacco Antonio , Chen Changzhong , Runnels Judith , Leleu Xavier , Azab Feda , Azab Abdel Kareem , Jia Xiaoying , Ngo Hai T. , Melhem Molly R. , Burwick Nicholas , Varticovski Lyuba , Novina Carl D. , Rollins Barrett J. , Anderson Kenneth C. , Ghobrial Irene M.
Published: December 2008

Multilevel genetic characterization of Waldenström macroglobulinemia (WM) is required to improve our understanding of the underlying molecular changes that lead to the initiation and progression of this disease. We performed microRNA-expression profiling of bone marrow–derived CD19+ WM cells, compared with their normal cellular counterparts and validated data by quantitative reverse-transcription–polymerase chain reaction (qRT-PCR). We identified a WM-specific microRNA signature characterized by increased expression of microRNA-363*/-206/-494/-155/-184/-542-3p, and decreased expression of microRNA-9* (ANOVA; P < .01). We found that microRNA-155 regulates proliferation and growth of WM cells in vitro and in vivo, by inhibiting MAPK/ERK, PI3/AKT, and NF-κB pathways. Potential microRNA-155 target genes were identified using gene-expression profiling and included genes involved in cell-cycle progression, adhesion, and migration. Importantly, increased expression of the 6 miRNAs significantly correlated with a poorer outcome predicted by the International Prognostic Staging System for WM. We further demonstrated that therapeutic agents commonly used in WM alter the levels of the major miRNAs identified, by inducing downmodulation of 5 increased miRNAs and up-modulation of patient-downexpressed miRNA-9*. These data indicate that microRNAs play a pivotal role in the biology of WM; represent important prognostic marker; and provide the basis for the development of new microRNA-based targeted therapies in WM.
Mesenchymal stem cell–mediated ectopic hematopoiesis alleviates aging-related phenotype in immunocompromised mice
Authors: Yamaza Takayoshi , Miura Yasuo , Akiyama Kentaro , Bi Yanming , Sonoyama Wataru , Gronthos Stan , Chen WanJun , Le Anh , Shi Songtao
Published: December 2008

Subcutaneous transplants of bone marrow mesenchymal stem cells (BMMSCs) are capable of generating ectopic bone and organizing functional hematopoietic marrow elements in animal models. Here we report that immunocompromised mice received subcutaneous BMMSC transplants using hydroxyapatite tricalcium phosphate as a carrier suppressed age-related degeneration in multiple organs and benefited an increase in life span extension compared with control littermates. The newly organized ectopic bone/marrow system restores active hematopoiesis via the erythropoietin receptor/signal transducer and activator of transcription 5 (Stat5) pathway. Furthermore, the BMMSC recipient mice showed elevated level of Klotho and suppression of insulin-like growth factor I signaling, which may be the mechanism contributing to the alleviation of aging-like phenotypes and prolongation of life in the treated mice. This work reveals that erythropoietin receptor/Stat5 pathway contributes to BMMSC-organized ectopic hematopoiesis, which may offer a treatment paradigm of reversing age-related degeneration of multiple organs in adult immunocompromised mice.
Investigation of Structure-Activity Relationships of Oxyntomodulin (Oxm) Using Oxm Analogs
Authors: Druce Maralyn R. , Minnion James S. , Field Benjamin C. T. , Patel Sejal R. , Shillito Joyceline C. , Tilby Michael , Beale Kylie E. L. , Murphy Kevin G. , Ghatei Mohammad A. , Bloom Stephen R.
Published: December 2008

Oxyntomodulin (Oxm) is an intestinal peptide that inhibits food intake and body weight in rodents and humans. These studies used peptide analogs to study aspects of structure and function of Oxm, and the sensitivity of parts of the Oxm sequence to degradation. Analogs of Oxm were synthesized and studied using receptor binding and degradation studies in vitro. Their effects on food intake and conditioned taste avoidance were measured in vivo in rodents. Oxm breakdown by the enzyme dipeptidyl peptidase IV (DPPIV) was demonstrated in vitro and in vivo. In vitro degradation was reduced and in vivo bioactivity increased by inhibitors of DPPIV. Modifications to the N terminus of Oxm modulated binding to the glucagon-like peptide (GLP)-1 receptor and degradation by DPPIV. Modifications to the midsection of Oxm modulated binding to the GLP-1 receptor and degradation by neutral endopeptidase. These modifications also altered bioactivity in vivo. The C-terminal octapeptide of Oxm was shown to contribute to the properties of Oxm in vitro and in vivo but was not alone sufficient for the effects of the peptide. Elongation and acylation of the C terminus of Oxm altered GLP-1 receptor binding and duration of action in vivo, which may be due to changes in peptide clearance. An Oxm analog was developed with enhanced pharmaceutical characteristics, with greater potency and longevity with respect to effects on food intake. These studies suggest that Oxm is a potential target for antiobesity drug design.
Estrogen Receptor-β Agonist Diarylpropionitrile: Biological Activities of R- and S-Enantiomers on Behavior and Hormonal Response to Stress
Authors: Weiser Michael J. , Wu T. John , Handa Robert J.
Published: December 2008

Estrogens have been shown to have positive and negative effects on anxiety and depressive-like behaviors, perhaps explained by the existence of two distinct estrogen receptor (ER) systems, ERα and ERβ. The ERβ agonist, diarylpropionitrile (DPN) has been shown to have anxiolytic properties in rats. DPN exists as a racemic mixture of two enantiomers, R-DPN and S-DPN. In this study, we compared R-DPN and S-DPN for their in vitro binding affinity, ability to activate transcription in vitro at an estrogen response element, and in vivo endocrine and behavioral responses. In vitro binding studies using recombinant rat ERβ revealed that S-DPN has a severalfold greater relative binding affinity for ERβ than does R-DPN. Furthermore, cotransfection of N-38 immortalized hypothalamic cells with an estrogen response element-luc reporter and ERβ revealed that S-DPN is a potent activator of transcription in vitro, whereas R-DPN is not. Subsequently, we examined anxiety-like behaviors using the open-field test and elevated plus maze or depressive-like behaviors, using the forced swim test. Ovariectomized young adult female Sprague Dawley rats treated with racemic DPN, S-DPN, and the ERβ agonist, WAY-200070, showed significantly decreased anxiety-like behaviors in both the open-field and elevated plus maze and significantly less depressive-like behaviors in the forced swim test compared with vehicle-, R-DPN-, or propylpyrazoletriol (ERα agonist)-treated animals. In concordance with the relative binding affinity and transcriptional potency, these results demonstrate that the S-enantiomer is the biologically active form of DPN. These studies also indicate that estrogen’s positive effects on mood, including its anxiolytic and antidepressive actions, are due to its actions at ERβ.
Prototyping artificial jaws for the robotic dental testing simulator
Authors: Alemzadeh K , Raabe D
Published: December 2008

This paper presents a robot periphery prototyped for the six-degrees-of-freedom robotic dental testing simulator, simulating the wear of materials on dental components, such as individual teeth, crowns, bridges, or a full set of teeth. The robot periphery consists of the artificial jaws and compliance module. The jaws have been reverse engineered and represent a human-like mandible and maxilla with artificial teeth. Each clinically fabricated tooth consists of a crown and glass ceramic roots which are connected using resin cement. Normal clinical occlusion of the artificial jaws assembly was emulated by a dental articulator based on ‘Andrew's six keys to occlusion’. The radii of the von Spee curve, the Monson curve, and the Wilson curve were also measured as important jaw characteristic indicators to aid normal occlusion. A compliance module had to be built between the lower jaw and the robot platform to sustain the fluctuating forces that occur during normal chewing in the occlusal contact areas, where these high bite forces are major causes of dental component failure. A strain gauge force transducer has been integrated into the machined lower jaw, underneath the second molars, to measure axial biting forces applied to the posterior teeth. The experiments conducted have shown that the sensor is able to sense small changes in the compression force satisfactorily, when applied perpendicular to the occlusal surfaces of the teeth.
An analysis of the strain field in biaxial Flexcell membranes for different waveforms and frequencies
Authors: Colombo A , Cahill P A , Lally C
Published: December 2008

Mechanical stimuli have been shown to affect cell behaviour in terms of proliferation, apoptosis, and protein expression. In terms of cardiovascular diseases, for example, endothelial and smooth muscle cells exposed to an abnormal strain environment have been associated with atherosclerosis and in-stent restenosis. The FX-4000™ system (Flexercell® Tension Plus System, Flexcell Corporation, McKeesport, Pennsylvania, USA) is an in-vitro system that is widely used to strain cells in order to evaluate their response to strain. The precision, accuracy, and repeatability of the strains controlled by the system are therefore crucial to analyse and interpret the results confidently. The aim of this study was to investigate the mechanical behaviour of the FX-4000™ Flexercell® six-well-plate silicon membranes for static and dynamic cyclic strains by measuring the maximum peak strain and analysing the change in the membrane deformation after cyclic strain for 0 h, 24 h, and 48 h at different strain amplitudes and frequencies. The results of the tests conducted demonstrate notable differences between the measured strains of the membranes in comparison with both the inputs and the outputs of the Flexcell® software. The calibration method used by Flexcell® International assumes that the strain values determined for a given vacuum pressure on the silicone membranes are reliable for different waveforms and frequencies. The data reported here clearly indicate that this is not the case. The results indicate that a unique calibration pressure—strain curve must be determined for each test given the viscoelastic nature of the Flexcell system. A new method to calibrate the machine in house was applied using new pressure—strain equations. This new calibration method has been presented and should enable researchers using the Flexcell® machine to set up their cell experiments more accurately.
Morphology and compression behaviour of biodegradable scaffolds produced by the sintering process
Authors: Ghassemieh E
Published: December 2008

Porous poly(l-lactic acid) (PLA) scaffolds of 85 per cent and 90 per cent porosity are prepared using polymer sintering and porogen leaching method. Different weight fractions of 10 per cent, 30 per cent, and 50 per cent of hydroxyapatite (HA) are added to the PLA to control the acidity and degradation rate. The three-dimensional (3D) morphology and surface porosity are tested using micro-computer tomography (micro-CT), optical microscopy, and scanning electron microscopy (SEM). Results indicate that the surface porosity does not change on the addition of HA. The micro-CT examinations show a slight decrease in the pore size and increase in the wall thickness accompanied by reduced anisotropy for the scaffolds containing HA. Scanning electron micrographs show detectable interconnected pores for the scaffold with pure PLA. Addition of the HA results in agglomeration of the HA particles and reduced leaching of the porogen. Compression tests of the scaffold identify three stages in the stress—strain curve. The addition of HA results in a reduction in the modulus of the scaffold at the first stage of elastic bending of the wall, but this is reversed for the second and third stages of collapse of the wall and densification in the compression tests. In the scaffolds with 85 per cent porosity, the addition of a high percentage of HA could result in 70 per cent decrease in stiffness in the first stage, 200 per cent increase in stiffness in the second stage, and 20 per cent increase in stiffness in the third stage. The results of these tests are compared with the Gibson cellular material model that is proposed for prediction of the behaviour of cellular material under compression. The pH and molecular weight changes are tracked for the scaffolds within a period of 35 days. The addition of HA keeps the pH in the alkaline region, which results in higher rate of degradation at an early period of observation, followed by a reduced rate of degradation later in the process. The final molecular weight is higher for the scaffolds with HA than for scaffolds of pure PLA. The manufactured scaffolds offer acceptable properties in terms of the pore size range and interconnectivity of the pores and porosity for non-load-bearing bone graft substitute; however, improvement to the mixing of the phases of PLA and HA is required to achieve better integrity of the composite scaffolds.
Bone mineral density assessment using the EOS® low-dose X-ray device: A feasibility study
Authors: Sapin E , Briot K , Kolta S , Gravel P , Skalli W , Roux C , Mitton D
Published: December 2008

To predict bone strength in the case of osteoporosis, it could be a real benefit to assess the three-dimensional (3D) geometry and the bone mineral density (BMD) with a single low-dose X-ray device, such as the EOS system (Biospace Med, Paris, France). EOS 3D reconstructions of the spine have already been validated. Thus, this study aims at evaluating the accuracy of this low-dose system as a densitometer first ex vivo. The European Spine Phantom (ESP) (number 129) was scanned ten times using both the EOS and a Hologic device (Hologic, Inc., Massachusetts, USA). Accuracy was given by the sum of the systematic error (difference between BMDs assessed and true values given by the phantom manufacturer) and the random error (coefficient of variation). EOS BMDs and Hologic BMDs of 41 ex-vivo vertebrae were calculated and compared. The reproducibility of the method evaluating the EOS BMD was assessed giving the coefficient of variation of three measurements of the 41 vertebrae. The accuracy of the EOS system is below 5.2 per cent, versus 7.2 per cent for the Hologic system in the same conditions. EOS BMDs are significantly higher than Hologic BMDs, but they are strongly correlated. The reproducibility of the method of assessment is equal to 0.95 per cent. The EOS system is accurate for ex-vivo BMD assessments, which is promising regarding the use of this new system to predict vertebral strength.
Haemodynamic analysis of coronary artery bypass grafting in a non-linear deformable artery and Newtonian pulsatile blood flow
Authors: Kouhi E , Morsi Y S , Masood S H
Published: December 2008

A three-dimensional (3D) computational model of stenotic coronary artery bypass grafting (CABG) system with fluid—structure interaction (FSI) using realistic physiological conditions is introduced. Unsteady pulsatile blood flow is applied to the wall of non-linear deformable arteries over the systolic period. In the analysis, the arbitrarily Lagrangian—Eulerian (ALE) formulation is used to couple the fluid region and solid domain. The method couples the equations of the deformation of the artery wall and applies them as the fluid domain boundary condition. The flow distribution and haemodynamic forces are presented in terms of velocity profiles and temporal and spatial wall shear stresses (WSSs) at the distal area. Rapid changes in the flow fields are observed in the early stages of the cardiac cycle, which alters the location of the recirculation zone from the toe to the host bed and then to the heel. The migration of the recirculation zone, considering the effect of deformability of the artery wall, indicates the same trend as the rigid wall model according to the location of low and high WSSs. However, the WSSs in the critical areas such as toe, heel, and suture lines are found to have dramatic drops in magnitudes in comparison with those of the rigid wall model. This could initiate the promotion of intimal hyperplasia (IH) and may cause an early graft failure in CABG.
Properties of a porous Ti—6Al—4V implant with a low stiffness for biomedical application
Authors: Li X , Wang C-T , Zhang W-G , Li Y-C
Published: December 2008

Porous Ti—6Al—4V alloy was fabricated using the electron beam melting (EBM) process. The phases of the as-received powder and fabricated samples were characterized using X-ray diffraction (XRD) analysis. The XRD peaks of both diffraction patterns agree well, which indicated that the EBM process has not changed the composition of Ti—6Al—4V. The fabricated samples exhibited a Vickers microhardness value of around 428 HV. The compression and three-point bending tests were performed to evaluate the mechanical properties of the porous Ti—6Al—4V implant with a porosity of around 60 per cent. The compressive yield strength, Young's modulus, and ultimate compressive strength were 194.6 MPa, 4.25 GPa, and 222.6 MPa respectively. The bending stiffness and bending strength were 3.7 GPa and 126.3 MPa respectively. These results demonstrated that the porous Ti—6Al—4V implant with a low stiffness and high porosity could be a promising biomaterial for biomedical applications.
Effects of age and gender on the movement workspace of the trapeziometacarpal joint
Authors: Kuo L-C , Cooney III W P , An K-N , Lai K-Y , Wang S-M , Su F-C
Published: December 2008

While researchers have suggested that joint mobility would probably be affected by age and gender, research findings often present discrepancies. Little research has been performed on the factors which effect mobility of the trapeziometacarpal (TMC) joint. The purpose of this study was to address the effects of age and gender on the ranges of motion of the normal TMC joint. Eighty normal subjects divided into four age groups participated in this study. The TMC joint motions were recorded using an electromagnetic tracking system. In order to achieve a maximal range of TMC joint motion which was defined as the maximal workspace, each subject was asked to perform actively maximal circumduction, flexion—extension, and abduction—adduction of the TMC joint. Numerical and statistical methods were used to compute the TMC workspace and to detect significant differences. A workspace-to-length ratio was determined as an index to examine the effects of the age and gender on the joint mobility. The results demonstrated that age and gender had significant influences on the TMC workspace among the groups studied. The understanding of TMC joint mobility under different age and gender conditions is achieved through this study. The findings can be used to report clinical measures in the determination of the extent of impairment of osteoarthritis as well as the outcomes between pre- and post-surgical (or non-surgical) interventions.
C-Reactive Protein Concentrations Are Very High and More Stable over Time Than the Traditional Vascular Risk Factors Total Cholesterol and Systolic Blood Pressure in an Australian Aboriginal Cohort
Authors: Shemesh Tomer , Rowley Kevin G , Jenkins Alicia J , Best James D , O'Dea Kerin
Published: December 2008

Background: Stability of circulating high-sensitivity C-reactive protein (hsCRP) concentrations has implications for its utility in assessing cardiovascular disease (CVD) risk. We sought to determine hsCRP reproducibility in an indigenous Australian cohort with a view to use hsCRP as a marker of future CVD in community-based risk-factor screenings.

Methods: Seventy people living in a community on the northern coast of Australia participated in 2 risk-factor screenings over a median (interquartile range) follow-up time of 829 (814–1001) days. hsCRP was measured by high-sensitivity nephelometry.

Results: Geometric mean hsCRP concentrations at baseline and follow-up were 4.5 and 5.1 mg/L, respectively (P = 0.220), and Pearson product-moment correlation was 0.775. The proportion of people at high CVD risk (hsCRP >3.0 mg/L) at baseline was 67.1% and remained consistently high (68.6%) at follow-up. Linear regression analysis for follow-up hsCRP as a function of baseline hsCRP, sex, and differences in total and regional body fatness showed that baseline hsCRP was the single predictor in the model, accounting for 63.9% of the total variance in follow-up hsCRP (Pmodel < 0.001). Prevalence agreement (95% CI) between baseline and follow-up for the hsCRP >3.0 mg/L category was 84% (73%–92%) (PMcNemar = not significant), and κ coefficient was fair (0.64, compared with 0.31 for systolic blood pressure ≥140 mmHg and 0.43 for total cholesterol ≥5.5 mmol/L).

Conclusions: hsCRP concentrations remained consistently reproducible over time across a wide concentration range in an Aboriginal cohort. Correlations between concentrations over time were better than for other traditional CVD risk factors. hsCRP concentration has potential as a marker of future CVD risk.
Oxidized LDL Receptor LOX-1 Binds to C-Reactive Protein and Mediates Its Vascular Effects
Authors: Fujita Yoshiko , Kakino Akemi , Nishimichi Norihisa , Yamaguchi Saburo , Sato Yuko , Machida Sachiko , Cominacini Luciano , Delneste Yves , Matsuda Haruo , Sawamura Tatsuya
Published: December 2008

Background: C-reactive protein (CRP) exerts biological activity on vascular endothelial cells. This activity may promote atherothrombosis, but the effects of this activity are still controversial. Lectin-like oxidized LDL receptor-1 (LOX-1), the oxidized LDL receptor on endothelial cells, is involved in endothelial dysfunction induced by oxidized LDL.

methods: We used laser confocal microscopy to examine and fluorescence cell image analysis to quantify the binding of fluorescently labeled CRP to cells expressing LOX-1. We then examined the binding of unlabeled CRP to recombinant human LOX-1 in a cell-free system. Small interfering RNAs (siRNAs) against LOX-1 were applied to cultured bovine endothelial cells to analyze the role of LOX-1 in native cells. To observe its in vivo effects, we injected CRP intradermally in stroke-prone spontaneously hypertensive (SHR-SP) rats and analyzed vascular permeability.

results: CRP bound to LOX-1–expressing cells in parallel with the induction of LOX-1 expression. CRP dose-dependently bound to the cell line and recombinant LOX-1, with significant binding detected at 0.3 mg/L CRP concentration. The Kd value of the binding was calculated to be 1.6 × 10–7 mol/L. siRNA against LOX-1 significantly inhibited the binding of fluorescently labeled CRP to the endothelial cells, whereas control RNA did not. In vivo, intradermal injection of CRP-induced vascular exudation of Evans blue dye in SHR-SP rats, in which expression of LOX-1 is greatly enhanced. Anti–LOX-1 antibody significantly suppressed vascular permeability.

Conclusions: CRP and oxidized LDL-receptor LOX-1 directly interact with each other. Two risk factors for ischemic heart diseases, CRP and oxidized LDL, share a common molecule, LOX-1, as their receptor.
Uterine influences on embryogenesis and early placentation in the horse revealed by transfer of day 10 embryos to day 3 recipient mares
Authors: Wilsher Sandra , Allen W R
Published: December 2008

Eight day 10 horse embryos were transferred non-surgically to recipient mares that had ovulated 7 days after the donors. The embryonic vesicle was seen ultrasonographically in all eight recipients, and three out of eight (38%) of the vesicles developed an embryo proper with a beating heart. Conceptus expansion was initially slower than that in control mares but continued until day 22 (recipient day 15). Time of fixation of the vesicle was related to its diameter, rather than uterine stage. Although the embryo proper first appeared ultrasonographically on day 22, as normal, it grew more slowly and the allantois expanded more slowly than that in control mares with normal pregnancies. The development of endometrial cups and their secretion of equine chorionic gonadotropin in the two mares allowed to remain pregnant to >50 days occurred at a conceptus age ∼7 days later than that in the control mares. The results demonstrated the uniqueness of the horse conceptus in being able to overcome a 7-day asynchrony with the uterus, and also highlighted the overriding influence of the uterine environment on conceptus development in the mare.
Accessing Time–Varying Forces on the Vibrating Tip of the Dynamic Atomic Force Microscope to Map Material Composition
Authors: Sahin Ozgur
Published: December 2008

In dynamic atomic force microscopes the primary physical quantities being measured are the amplitude/phase or amplitude/frequency of the vibrating force probe. Topographic images with spatial resolutions down to the atomic scale can be obtained by mapping these measurements across the sample surface under feedback control. During the imaging process the vibrating tip is observing tip–sample interaction potentials (force–distance relationships) at every point on the surface. The interaction potential is a superposition of short‐ and long–distance interactions of various origins determined by the material compositions of the tip, sample, and the medium of imaging. In principle, measurement of tip–sample interaction potential should allow determination and mapping of material composition of the sample. However, a single measurement of amplitude/phase or amplitude/frequency in dynamic atomic force microscopes is not enough to characterize a complicated tip–sample interaction potential. Recent developments in the understanding of dynamics of the vibrating force probe (cantilever), together with specially designed cantilevers that utilize torsional vibrations in addition to conventional vertical vibrations, enable the recovery of tip–sample interaction potentials at a timescale less than a millisecond. Here, with theory and experiments, we discuss how these cantilevers recover the information about the tip–sample interaction forces and give an example of compositional mapping on a polymeric material system.
Endogenous Fibroblastic Progenitor Cells in the Adult Mouse Lung Are Highly Enriched in the Sca-1 Positive Cell Fraction
Authors: McQualter Jonathan L. , Brouard Nathalie , Williams Brenda , Baird Brandi N. , Sims-Lucas Sunder , Yuen Karen , Nilsson Susan K. , Simmons Paul J. , Bertoncello Ivan
Published: December 2008

Originally identified as a marker specifying murine hematopoietic stem cells, the Sca-1 antigen has since been shown to be differentially expressed by candidate stem cells in tissues including vascular endothelium, skeletal muscle, mammary gland, and prostate of adult mice. In the adult murine lung, Sca-1 has previously been identified as a selectable marker for the isolation of candidate nonhematopoietic (CD45−), nonendothelial (CD31−) bronchioalveolar stem cells (BASC) located at the bronchioalveolar duct junction that coexpress surfactant protein C and the Clara cell specific protein. Our systematic analysis of CD45−CD31−Sca-1+ cells in fetal, neonatal, and adult lung shows that very few of these cells are detectable prior to birth but expand exponentially postnatally coinciding with the transition from the saccular to the alveolar stage of lung development. Unlike candidate BASCs, the CD45−CD31−Sca-1+CD34+ cell fraction we describe coexpresses immunophenotypic markers (Thy-1 and platelet-derived growth factor receptor α) that define lung fibroblastic rather than epithelial cells. The mesenchymal “signature” of the CD45−CD31−Sca-1+CD34+ cell fraction is further confirmed by transcriptional profiling, by cell culture studies demonstrating enrichment for clonogenic lipofibroblastic and nonlipofibroblastic progenitors, and by immunohistochemical localization of Sca-1 in perivascular cells of the lung parenchyma. Although the CD45−CD31−Sca-1+CD34+ cell phenotype does define endogenous clonogenic progenitor cells in the adult murine lung, our data indicate that these progenitors are predominantly representative of mesenchymal cell lineages, and highlights the pressing need for the identification of alternative markers and robust functional assays for the identification and characterization of epithelial and fibroblastic stem and progenitor cell populations in the adult lung.
The role of hydrochlorofluorocarbon densifiers in the formation of clathrate hydrates in deep boreholes and subglacial environments
Authors: Murshed M. Mangir , Faria Sérgio H. , Kuhs Werner F. , Sepp Kipfstuhl  , Wilhelms Frank
Published: December 2008

Clear evidence for the formation of mixed clathrate hydrates of air and hydrochlorofluorocarbon densifier (known as HCFC-141b, sometimes also called R-141b) is found by means of synchrotron X-ray diffraction and Raman spectroscopy on a sample recovered from the bottom of the EPICA Dronning Maud Land deep borehole in Antarctica. Subglacial water (SGW) appears to have reacted with the drilling liquid to build a large lump of clathrate hydrate. The hydrate growth may well have been accelerated by the stirring of the SGW–densifier mixture during drilling. Moreover, dissolved air in the SGW appears to have participated in the formation of mixed hydrates of air and HCFC-141b as evidenced by the concomitant appearance of Raman signals from both constituents. Our findings elucidate to some extent the meaning of earlier accounts of the formation of ‘heavy chips’ that may sink to the bottom of the borehole, possibly affecting or even impeding the drilling advance. These observations raise concerns with respect to the use of HCFC-141b densifiers in ice-core drilling liquids under warm ice conditions.
The Hans Tausen drill: design, performance, further developments and some lessons learned
Authors: Johnsen Sigfús J. , Hansen Steffen Bo , Sheldon Simon G. , Dahl-Jensen Dorthe , Steffensen Jørgen P. , Augustin Laurent , Journé Paul , Alemany Olivier , Rufli Henry , Schwander Jakob , Azuma Nobuhiko , Motoyama Hideaki , Popp Trevor , Talalay Pavel , Thorsteinsson Thorsteinn , Wilhelms Frank , Zagorodnov Victor
Published: December 2008

In the mid-1990s, excellent results from the GRIP and GISP2 deep drilling projects in Greenland opened up funding for continued ice-coring efforts in Antarctica (EPICA) and Greenland (NorthGRIP). The Glaciology Group of the Niels Bohr Institute, University of Copenhagen, was assigned the task of providing drilling capability for these projects, as it had done for the GRIP project. The group decided to further simplify existing deep drill designs for better reliability and ease of handling. The drill design decided upon was successfully tested on Hans Tausen Ice Cap, Peary Land, Greenland, in 1995. The 5.0m long Hans Tausen (HT) drill was a prototype for the ~11m long EPICA and NorthGRIP versions of the drill which were mechanically identical to the HT drill except for a much longer core barrel and chips chamber. These drills could deliver up to 4m long ice cores after some design improvements had been introduced. The Berkner Island (Antarctica) drill is also an extended HT drill capable of drilling 2 m long cores. The success of the mechanical design of the HT drill is manifested by over 12 km of good-quality ice cores drilled by the HT drill and its derivatives since 1995.
Drilling to the beds of the Greenland and Antarctic ice sheets: a review
Authors: Bentley Charles R. , Koci Bruce R.
Published: December 2008

We give a review of drilling to the beds of the Greenland and Antarctic ice sheets, with a history of just a century. We use a chronological rather than a geographical ordering to emphasize the way drilling has developed. The review is divided into two parts: core drilling and hole-only drilling for access to the beds or the deep interior of the ice sheets. This is an overview, not a comprehensive report on each project. While we have endeavoured to include all projects that fit our selection criteria, we have not provided all the technical details.
Viscosity and density of a two-phase drilling fluid
Authors: Alemany O. , Mityar H.
Published: December 2008

Many ice-core drilling projects expect to reach depths greater than 1000 m. At such depths it is necessary to fill the borehole with a fluid to compensate the ice pressure and avoid the resulting significant hole closure. Knowledge of the ice-chips and drilling-fluid circulation parameters (e.g. flow rate, pressure drop, velocity) is essential for understanding the behaviour of the fluid around the drill and will support drill design through a better parameterization in models. A characterization of the dynamic viscosity and of the density of the ice-chips and drilling-fluid mixture is required to calculate these circulation parameters. The goal of this study is to propose a method to calculate, to a first approximation, both these physical properties. The relationships presented here have been established after experimentation, building on prior assumptions taken from the literature.
Dimethyl siloxane oils as an alternative borehole fluid
Authors: Talalay P.G.
Published: December 2008

Finding a new safe and ecologically friendly borehole fluid is one of the most pressing problems for forthcoming ice-drilling projects. Not all recent borehole fluids qualify as intelligent choices from safety, environmental and other technological standpoints. We propose the use of silicone oils as the borehole fluid. The most suitable type of silicone oils for deep ice drilling are low-molecular (or volatile) dimethyl siloxane oils (DSOs). Low-molecular DSOs are clear, water-white, tasteless, odorless, neutral liquids. They are hydrophobic and inert substances that are stable to water, air, oxygen, metals, wood, paper, plastics, etc. Of the DSOs, class 2 grades of KF96-1.5cs and KF96-2.0cs most fully fit our criteria for choice as borehole fluids. The final conclusion as to the suitability of DSOs for ice deep drilling will be made after the experiments in a test borehole.
Nonflowers near the base of extant angiosperms? Spatiotemporal arrangement of organs in reproductive units of Hydatellaceae and its bearing on the origin of the flower
Authors: Rudall Paula J. , Remizowa Margarita V. , Prenner Gerhard , Prychid Christina J. , Tuckett Renee E. , Sokoloff Dmitry D.
Published: December 2008

Reproductive units (RUs) of Trithuria, the sole genus of the early‐divergent angiosperm family Hydatellaceae, are compared with flowers of their close relatives in Cabombaceae (Nymphaeales). Trithuria RUs combine features of flowers and inflorescences. They differ from typical flowers in possessing an “inside‐out” morphology, with carpels surrounding stamens; furthermore, carpels develop centrifugally, in contrast to centripetal or simultaneous development in typical flowers. Trithuria RUs could be interpreted as pseudanthia of two or more cymose partial inflorescences enclosed within an involucre, but the bractlike involucral phyllomes do not subtend partial inflorescences and hence collectively resemble a typical perianth. Teratological forms of T. submersa indicate a tendency to fasciation and demonstrate that the inside‐out structure—the primary feature that separates RUs of Hydatellaceae from more orthodox angiosperm flowers—can be at least partially modified, thus producing a morphology that is closer to an orthodox flower. The Trithuria RU could be described as a “nonflower”, i.e., a structure that contains typical angiosperm carpels and stamens but does not allow recognition of a typical angiosperm flower. The term nonflower could combine cases of secondary loss of flower identity and cases of a prefloral condition, similar to those that gave rise to the angiosperm flower. Nonhomology among some angiosperm flowers could be due to iterative shifts between nonfloral construction and flower/inflorescence organization of reproductive organs. Potential testing of these hypotheses using evolutionary‐developmental genetics is explored using preliminary data from immunolocalization of the floral meristem identity gene LEAFY in T. submersa, which indicated protein expression at different hierarchical levels.