bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitive Quantitative Analysis of C-Peptide in Human Plasma by 2-Dimensional Liquid Chromatography–Mass Spectrometry Isotope-Dilution Assay
Authors: Rogatsky Eduard , Balent Beate , Goswami Gayotri , Tomuta Vlad , Jayatillake Harsha , Cruikshank Greg , Vele Louis , Stein Daniel T 
Published: March 2006

AbstractBackground: Isotope-dilution assays (IDAs) are well established for quantification of metabolites or small drug molecules in biological fluids. Because of their increased specificity, IDAs are an alternative to immunoassays for measuring C-peptide.Methods: We evaluated a 2-dimensional liquid chromatography–mass spectrometry (2D LC/MS) IDA method. Sample preparation was by off-line solid-phase extraction, and C-peptide separation was performed on an Agilent 1100 2D LC system with a purification method based on high-pressure switching between 2 high-resolution reversed-phase columns. Because of the low fragmentation efficiency of C-peptide, multiple-reaction monitoring analysis was omitted and selective-ion monitoring mode was chosen for quantification. Native and isotope-labeled ([M+18] and [M+30]) C-peptides were monitored in the +3 state at m/z 1007.7, 1013.7, and 1017.7.Results: The assay was linear (r2 = 0.9995), with a detection limit of 300 amole (1 pg) on column. Inter- and intraday CVs for C-peptide were ≤2%. Comparison with an established polyclonal-based RIA showed high correlation (r = 0.964). Plasma concentrations of total C-peptide measured by RIA were consistently higher than by IDA LC/MS, consistent with the higher specificity of IDAs compared with immunoassays.Conclusions: The 2D LC/MS IDA approach eliminates matrix effects, enhancing assay performance and reliability, and has a detection limit 100-fold lower than any previously reported LC/MS method. Isotope-labeled C-peptide(s) can be clearly differentiated from endogenous C-peptide by the difference in m/z ratio, so that both peptides can be quantified simultaneously. The method is highly precise, robust, and applicable to pharmacokinetic detection of plasma peptides.
Transplantation of Human Embryonic Stem Cell-Derived Cells to a Rat Model of Parkinson's Disease: Effect of In Vitro Differentiation on Graft Survival and Teratoma Formation
Authors: Brederlau Anke , Correia Ana Sofia , Anisimov Sergey V. , Elmi Muna , Paul Gesine , Roybon Laurent , Morizane Asuka , Bergquist Filip , Riebe Ilse , Nannmark Ulf , Carta Manolo , Hanse Erik , Takahashi Jun , Sasai Yoshiki , Funa Keiko , Brundin Patrick , Eriksson Peter S. , Li Jia-Yi 
Published: March 2006

Abstract
Human embryonic stem cells (hESCs) have been proposed as a source of dopamine (DA) neurons for transplantation in Parkinson's disease (PD). We have investigated the effect of in vitro predifferentiation on in vivo survival and differentiation of hESCs implanted into the 6-OHDA (6-hydroxydopamine)-lesion rat model of PD. The hESCs were cocultured with PA6 cells for 16, 20, or 23 days, leading to the in vitro differentiation into DA neurons. Grafted hESC-derived cells survived well and expressed neuronal markers. However, very few exhibited a DA neuron phenotype. Reversal of lesion-induced motor deficits was not observed. Rats grafted with hESCs predifferentiated in vitro for 16 days developed severe teratomas, whereas most rats grafted with hESCs predifferentiated for 20 and 23 days remained healthy until the end of the experiment. This indicates that prolonged in vitro differentiation of hESCs is essential for preventing formation of teratomas.
Failure of Transdifferentiation of Adult Hematopoietic Stem Cells into Neurons
Authors: Roybon Laurent , Ma Zhi , Asztely Fredrik , Fosum Anna , Jacobsen Sten Eirik W. , Brundin Patrik , Li Jia-Yi 
Published: March 2006

AbstractPrevious studies of bone marrow-derived stem cell transdifferentiation into neurons have not involved purified cell populations and determined their exact phenotype prior to differentiation. The present study investigates whether highly purified mouse adult hematopoietic stem cells (HSCs), characterized by lineage marker depletion and expression of the cell surface markers Sca1 and c-Kit (Lin− Sca1+ c-Kit+ [LSK]), can be stimulated to adopt a neuronal fate. When the HSCLSK cells were cultured in vitro in neuronal differentiation medium supplemented with retinoic acid, 50% of the cells expressed the neural progenitor marker nestin and no cells had become postmitotic. Electrophysiological recordings on neuron-like cells showed that these cells were incapable of generating action potentials. When the HSCLSK cells either were grown in vitro together with neural precursor cells or were transplanted into the striatum or cerebellum of wild-type mouse, they either differentiated into Iba1-immunopositive macrophage/microglia or died. In conclusion, we demonstrate that adult HSCLSK cells do not have the capacity to leave the hematopoietic lineage and differentiate into neurons.
Polyesters, Thermoplastic
Authors: East Anthony J. 
Published: March 2006

AbstractThis article covers semicrystalline thermoplastic polyesters and their applications as molding resins. The principal polymers described are PET, PBT, PEN, PTT, PCT, thermoplastic elastomers of the PBT–PTMEG‐T type, and liquid crystalline polymers. The raw materials for various polyesters and their production are described and general routes to polyester polymer synthesis outlined. Individual polyesters are described in more detail with particular reference to special features of their polymer chemistry. PET stretch blow‐molded bottles and containers are a very large market and the production of PET bottle resin by continuous polymerization and solid‐state polymerization is described together with an outline of the stretch blow‐molding process. Physical properties, polymer characterization and mechanical properties together with details of polymer injection molding are described.Particular reference is given to the growing demands for PCT of new electronic and electrical fabrication techniques such as surface mounting technology and its requirements for high temperature polymer properties. PBT polymer is described in detail. Flame‐retardant additives are described and how they affect polymer performance. Safety and health factors for the polymers in use are discussed.Liquid‐crystal polymers are relatively new high performance thermoplastics. The nature of the mesophase state and how LCPs differ from conventional materials is described. The LCP polymer synthesis is outlined and physical and mechanical properties of several commercial LCP polymers are given.
Polyimides
Authors: Bryant Robert G. 
Published: March 2006

Abstract

Polyimides are a class of high performance polymers that contain an imide group, defined as an sp
3
nitrogen bonded to two adjacent carbonyls. This imide structure is most commonly found as part of a five or six membered ring. Aromatic polyimides are noted for their mechanical properties, chemical resistance and dielectric strength. They exist as thermoplastics and thermosets and are available in many formats. Polyimides are used as hot melt adhesives, matrix resins for composites, dielectric films, photoimageable coatings, flex circuits, foams, wire insulation, thin walled tubing, molding resins and high performance bushings and seals. Products that compete with polyimides for niche applications include aerospace epoxies (Dow, Ciba and Shell), cyanate resins (Dow), polysulfones (Solvay), filled polycarbonates and polyesters (Dow, Amoco and GE), polybenzimidazoles (Hoechst‐Celanese) and some high Tg filled phenolics. Although polyimides command a premium price, their versatility, reliability, and demonstrated performance makes them suitable use in high performance applications where failure and replacement costs are high.
White Electroluminescence from a Single‐Polymer System with Simultaneous Two‐Color Emission: Polyfluorene as the Blue Host and a 2,1,3‐Benzothiadiazole Derivative as the Orange Dopant
Authors: Liu J. , Zhou Q. G. , Cheng Y. X. , Geng Y. H. , Wang L. X. , Ma D. G. , Jing X. B. , Wang F. S. 
Published: March 2006

AbstractNew single‐polymer electroluminescent systems containing two individual emission species—polyfluorenes as a blue host and 2,1,3‐benzothiadiazole derivative units as an orange dopant on the main chain—have been designed and synthesized. The resulting single polymers are found to have highly efficient white electroluminescence with simultaneous blue (λmax = 421 nm/445 nm) and orange emission (λmax = 564 nm) from the corresponding emitting species. The influence of the photoluminescence (PL) efficiencies of both the blue and orange species on the electroluminescence (EL) efficiencies of white polymer light‐emitting diodes (PLEDs) based on the single‐polymer systems has been investigated. The introduction of the highly efficient 4,7‐bis(4‐(N‐phenyl‐N‐(4‐methylphenyl)amino)phenyl)‐2,1,3‐benzothiadiazole unit to the main chain of polyfluorene provides significant improvement in EL efficiency. For a single‐layer device fabricated in air (indium tin oxide/poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonic acid/polymer/Ca/Al), pure‐white electroluminescence with Commission Internationale de l'Eclairage (CIE) coordinates of (0.35,0.32), maximum brightness of 12 300 cd m–2, luminance efficiency of 7.30 cd A–1, and power efficiency of 3.34 lm W–1 can be obtained. This device is approximately two times more efficient than that utilizing a single polyfluorene containing 1,8‐naphthalimide moieties, and shows remarkable improvement over the corresponding blend systems in terms of efficiency and color stability. Thermal treatment of the single‐layer device before cathode deposition leads to the further improvement of the device performance, with CIE coordinates of (0.35,0.34), turn‐on voltage of 3.5 V, luminance efficiency of 8.99 cd A–1, power efficiency of 5.75 lm W–1, external quantum efficiency of 3.8 %, and maximum brightness of 12 680 cd m–2. This performance is roughly comparable to that of white organic light‐emitting diodes (WOLEDs) with multilayer device structures and complicated fabrication processes.
Regulation of tack development of acrylate films by the properties of the support
Authors: Fike Gregory M. , Banerjee Sujit 
Published: March 2006

AbstractDrying an acrylate formulation on carbon and stainless steel coupons leads to films with dramatic differences in tack. The tack of the film deposited on stainless steel is high, as expected, but that of the film on carbon steel is much lower. This difference arises from changes in the polar component of the surface energy. Atomic force microscopy showed that the carbon steel‐based film had a rougher surface, and that the components separated into the valleys in the surface, thereby reducing the overall tack. The origin of the phenomenon lies in the nonuniformity of carbon steel. Local differences in heat transfer from the metal to the adjoining liquid layer gives rise to temperature differences at the surface of the film as it dries. This induces Marangoni flow, which leads to inhomogeneities in the composition and topology of the surface. © 2006 American Institute of Chemical Engineers AIChE J, 2006
On the breakup of fluid particles in turbulent flows
Authors: Andersson Ronnie , Andersson Bengt 
Published: March 2006

AbstractDynamics of bubble and drop breakup in turbulent flows have been studied in detail, using a high‐speed CCD camera. Analysis of breakup times, deformations, deformation velocities, number of fragments, and the resulting daughter size distributions show that there are several important differences in the breakup mechanism of bubbles and drops. It is shown that the increase in interfacial energy prior to breakup exceeds the increase after breakup. The use of an activation barrier that better describes the turbulent structures that can interact with fluid particles and also cause breakup is proposed. Measurements under identical hydrodynamic conditions reveal that an internal flow redistribution mechanism is responsible for generation of unequal‐sized bubble fragments. Due to the three orders of magnitude higher density of liquids than of gases, this mechanism does not occur for drops. The measurements also show that assumption of binary breakup is reasonable for bubbles but not for drops. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Movement‐related cortical potentials in primary lateral sclerosis
Authors: Bai Ou , Vorbach Sherry , Hallett Mark , Floeter Mary Kay 
Published: March 2006

AbstractObjectiveSome patients with primary lateral sclerosis (PLS) have a clinical course suggestive of a length‐dependent dying‐back of corticospinal axons. We measured movement‐related cortical potentials (MRCPs) in these patients to determine whether cortical functions that are generated through short, intracortical connections were preserved when functions conducted by longer corticospinal projections were impaired.MethodsAn electroencephalogram was recorded from scalp electrodes of 10 PLS patients and 7 age‐matched healthy control subjects as they made individual finger‐tap movements on a keypad. MRCPs were derived from back‐averaging the electroencephalogram to the movement.ResultsMRCPs produced by finger taps were markedly reduced in PLS patients, including components generated by premotor areas of the cortex as well as the primary motor cortex. In contrast, the β‐band event‐related desynchronization from the motor cortex was preserved.InterpretationThese findings suggest that impairment in PLS is not limited to the distal axons of corticospinal neurons, but also affects neurons within the primary motor cortex and premotor cortical areas. The loss of the MRCP may serve as a useful marker of upper motor neuron dysfunction. Preservation of event‐related desynchronization suggests that the cells of origin differ from the large pyramidal cells that generate the MRCP. Ann Neurol 2006;59:682–690
Microphthalmia and brain atrophy: A novel neurodegenerative disease
Authors: Kanavin Øivind J. , Haakonsen Monika , Server Andrès , Bajwa Tariq J. , van der Knaap Marjo S. , Strømme Petter 
Published: March 2006

AbstractObjectiveTo delineate the features of a novel neurodegenerative disease.MethodsWe report three children of three related families with congenital microphthalmia and blindness, and progressive spasticity, microcephaly, seizures, and profound mental retardation.ResultsA magnetic resonance imaging scan was normal at birth. However, follow‐up studies showed progressive atrophy involving the cerebral white matter and cortex, cerebellum, brainstem, and corpus callosum. The white matter changes extended into the subcortical region leaving only small islands of remaining cortical tissue. Known metabolic conditions involving white matter degeneration were excluded.InterpretationWe propose this to be a novel autosomal recessive neurodegenerative disorder to be coined MOBA (microphthalmia brain atrophy) disease. Ann Neurol 2006;59:719–723
Magnetic resonance imaging as a surrogate outcome measure of disability in multiple sclerosis: Have we been overly harsh in our assessment?
Authors: Goodin Douglas S. 
Published: March 2006

AbstractObjectiveThe validity of magnetic resonance imaging (MRI) as a surrogate outcome measure in multiple sclerosis (MS) clinical trials has been greeted skeptically both by the US Food and Drug Administration and by clinical researchers because the correlation between current MRI measures and clinical disability, although significant, has generally been low. Thus, the reported correlations have varied between ρ = 0.09 and ρ = 0.60, and have often been at the lower end of this range. Nevertheless, it still appears possible that this apparently poor correlation is due not to any deficiency either with our current MRI measures or with our disability scale, but rather to the intrinsic variability in the clinical expression of MS plaques in different anatomical locations.MethodsThis article explores this possibility through the development of a general mathematical model for the relation between MRI changes and clinical disability in patients with MS.ResultsUnder the conditions of this general model, the maximum expected correlation between clinical disability and MRI will typically be quite low (eg, ρ = 0.2–0.3), even when it is assumed that the MRI changes are the sole determinant of disability and, furthermore, that the scale used to measure disability is ideal.InterpretationThese observations, together with the significant relations already reported between MRI and disability (with observed correlations in the range of 0.2–0.6), actually suggest that our available clinical and MRI measures are considerably better than is currently believed and, in fact, that the MRI may be a valid surrogate marker in the assessment of treatment efficacy in MS. Ann Neurol 2006;59:597–605
Synthetic Multivalent Ligands as Probes of Signal Transduction
Authors: Kiessling Laura L. , Gestwicki Jason E. , Strong Laura E. 
Published: March 2006

AbstractCell‐surface receptors acquire information from the extracellular environment and coordinate intracellular responses. Many receptors do not operate as individual entities, but rather as part of dimeric or oligomeric complexes. Coupling the functions of multiple receptors may endow signaling pathways with the sensitivity and malleability required to govern cellular responses. Moreover, multireceptor signaling complexes may provide a means of spatially segregating otherwise degenerate signaling cascades. Understanding the mechanisms, extent, and consequences of receptor co‐localization and interreceptor communication is critical; chemical synthesis can provide compounds to address the role of receptor assembly in signal transduction. Multivalent ligands can be generated that possess a variety of sizes, shapes, valencies, orientations, and densities of binding elements. This Review focuses on the use of synthetic multivalent ligands to characterize receptor function.
Cues they use: clinicians' endorsement of risk cues in predictions of dangerousness
Authors: Odeh Michael S. , Zeiss Robert A. , Huss Matthew T. 
Published: March 2006

AbstractClinical predictions of violence are a necessary part of clinical practice despite extensive literature validating the use of actuarial rather than clinical prediction. The current study examined clinicians' use of risk cues in predictions of violence. Clinicians identified several risk cues as significant in clinical assessments of risk, including a history of assaults, hostility, medication noncompliance, paranoid delusions, presence of psychosis, and family problems. However, further results indicated that clinician‐endorsed risk cues lack predictive power in the present sample. Copyright © 2006 John Wiley & Sons, Ltd.
A comparison of selected Rorschach variables of violent female offenders and female non‐offenders
Authors: Weizmann‐Henelius Ghitta , Ilonen Tuula , Viemerö Vappu , Eronen Markku 
Published: March 2006

AbstractA national sample of incarcerated violent female offenders (N = 45) and a sample of female non‐offenders (N = 30) were compared on nine selected Rorschach CS (Exner, 2003) variables and three of the aggression variables of Gacono and Meloy (1994). The results indicate that an avoidant and inconsistent coping style was more characteristic of the offenders than the non‐offenders. The offenders were characterized by social immaturity and limited capacities to cope with stress as compared with the non‐offenders. No significant differences were found between the two groups in handling intense emotions. Although the aggressive scores revealed no discrimination between the groups, significant correlations were found between the aggressive content score and childhood victimization. An inverse relation was found between the aggressive past score and the emotional intensity of the violent offense. The study indicates that the selected RCS variables related to adaptive resources for coping discriminate between violent offenders and non‐offenders, but that the variables related to affective features need further examination. Copyright © 2006 John Wiley & Sons, Ltd.
Assessing the “evolving standards of decency:” perceptions of capital punishment for juveniles
Authors: Kalbeitzer Rachel , Sevin Goldstein Naomi E. 
Published: March 2006

AbstractThis study examines whether public opinion parallels recent judicial and statutory changes limiting the applicability of capital sentences to offenders younger than 18 years old. Two hundred and thirty‐five undergraduate students were administered a vignette of a capital case and asked to render a sentence of death or life in prison without parole. Results revealed that age of the defendant was not a significant predictor of sentence type; participants sentenced 16‐ and 17‐year‐old defendants similarly to 18‐ and 25‐year‐old defendants. Therefore, public opinion appears inconsistent with legal and legislative changes to abandon the practice of executing juveniles. Findings also suggested that perceived level of the defendant's responsibility and general opinion about capital sentences significantly predicted sentence type; perceptions of greater responsibility were associated with an increased likelihood of a death sentence. However, participants did not perceive differences in responsibility between juvenile and adult defendants. In addition, participants were more comfortable sentencing defendants to death compared with life in prison. Copyright © 2006 John Wiley & Sons, Ltd.
Opinion formation in evaluating the adjudicative competence and restorability of criminal defendants: a review of 8,000 evaluations
Authors: Warren Janet I. , Murrie Daniel C. , Stejskal William , Colwell Lori H. , Morris James , Chauhan Preeti , Dietz Park 
Published: March 2006

AbstractEvaluations of competence to stand trial (CST) are the most common type of criminal forensic evaluation conducted, and courts tend to defer to clinician opinions regarding a defendant's competence. Thus, it is important to study the ways in which clinicians arrive at opinions regarding adjudicative competence and the data they consider in forming their opinions. We reviewed 8,416 evaluations conducted by forensic evaluators in Virginia over a 12 year period, and examined (a) the clinical, demographic, and criminal characteristics of a defendant as related to opinions regarding competence, predicted restorability, and impairment on “prongs” of the Dusky standard, (b) process and outcome differences in evaluations conducted by psychiatrists versus psychologists and inpatient versus outpatient evaluators, and (c) the consistency of incompetence base rates over a 10 year period. Overall, clinicians opined that 19% of defendants were incompetent and considered 23% of these unlikely to be restored to competence. Not surprisingly, psychotic and organic/intellectual disorders were most strongly associated with findings of incompetence. However, there were some notable differences between evaluations by psychologists versus psychiatrists and between evaluations conducted in inpatient versus outpatient settings. Copyright © 2006 John Wiley & Sons, Ltd.