bluuebunny/crossref_metadata_2025 huggingface dataset:
Globalization and local response to epidemiological overlap in 21st century Ecuador
Authors: Waters William F
Published: May 2006

Background

Third World countries are confronted by a complex overlay of two sets of health problems. Traditional maladies, including communicable diseases, malnutrition, and environmental health hazards coexist with emerging health challenges, including cardiovascular disease, cancer, and increasing levels of obesity. Using Ecuador as an example, this paper proposes a conceptual framework for linking epidemiologic overlap to emerging social structures and processes at the national and global levels.

Discussion

Epidemiologic trends can be seen as part of broader processes related to globalization, but this does not imply that globalization is a monolithic force that inevitably and uniformly affects nations, communities, and households in the same manner. Rather, characteristics and forms of social organization at the subnational level can shape the way that globalization takes place. Thus, globalization has affected Ecuador in specific ways and is, at the same time, intimately related to the form in which the epidemiologic transition has transpired in that country.

Ecuador is among neither the poorest nor the wealthiest countries and its situation may illuminate trends in other parts of the world.

As in other countries, insertion into the global economy has not taken place in a vacuum; rather, Ecuador has experienced unprecedented social and demographic change in the past several decades, producing profound transformation in its social structure. Examples of local represent alternatives to centralized health systems that do not effectively address the complex overlay of traditional and emerging health problems.
Variations in chemokine receptor and cytokine expression during pregnancy in multiple sclerosis patients
Authors: López C , Comabella M , Tintoré M , Sastre-Garriga J , Montalban X
Published: May 2006

Although several T cell-mediated autoimmune diseases have shown a reduction in their clinical disease activity during pregnancy, the underlying mechanisms by which pregnancy causes such a beneficial effect on the disease activity are not fully understood. We performed a longitudinal study of chemokine receptors (CCR3, CCR4, CCR5, CXCR3, CXCR4) by flow cytometry in different subsets of peripheral blood mononuclear cells (PBMC) during pregnancy in multiple sclerosis (MS) patients. The levels of cytokine mRNA expression (IL-10, IFN-g) were also investigated by real-time quantitative reverse transcription polymerase chain reaction. The expression of CXCR3 by CD4 and CD8 positive T cells was decreased to a statistically significant extent during the second trimester of pregnancy. CD4 and CD8 T cells showed a statistically significant increase in the expression of CXCR4 during the third trimester of pregnancy. At the mRNA expression level, an increase in the IL-10/IFN-g ratio was observed during pregnancy, especially during the third trimester. These findings indicate immunomodulatory effects of pregnancy on the expression of chemokine receptors and cytokines, which may be related to changes in the clinical disease activity of T cell-mediated autoimmune diseases, such as MS.
How to detect cognitive dysfunction at early stages of multiple sclerosis?
Authors: Deloire M SA , Bonnet M C , Salort E , Arimone Y , Boudineau M , Petry K G , Brochet B
Published: May 2006

Detecting cognitive dysfunction may be clinically important during the early stages of multiple sclerosis (MS). We assessed a self-report questionnaire on cognitive complaints and individual neuropsychological tests to select patients with early relapsing-remitting MS (RRMS) who needed comprehensive cognitive testing.

Fifty-seven patients underwent neurological and neuropsychological assessment, including Rao’s Brief Repeatable Battery (BRB) and the complete SEP-59 Questionnaire, a French adaptation of the MSQOL-54, which contains four specific questions about self-perception of cognitive functions. Predictive values, specificity, sensitivity and accuracy of five individual neuropsychological tests-Selective Reminding Test, Symbol Digit Modalities Test (SDMT), Similarities Subtest, PASAT and Stroop Test-were calculated to predict cognitive impairment.

Only 10.5% of patients did not report any cognitive complaint, while most reported complaints. On the basis of cognitive performances, 59.7% of patients were classified as cognitively impaired, although only one cognitive score was correlated with cognitive complaints. Depressive symptoms and fatigue were associated with more cognitive complaints. Sensitivity of the SDMT to predict cognitive impairment was 74.2%, specificity was 76.9% and accuracy was 75.4%. Since, at this stage, patients’ cognitive complaints are already influenced by depression and fatigue and do not accurately reflect cognitive performances, the SDMT may help to select patients for testing with a more complete cognitive battery.
Earthquake Mitigation Decisions and Consequences
Authors: Bostrom Ann , Turaga Rama Mohana R. , Ponomariov Branco
Published: May 2006

A primary aim of recent earthquake engineering research has been to integrate analyses of social and technical systems, to take into account the potential consequences of earthquakes for society as a whole. In some cases the resulting decision frameworks treat acceptable consequences and risks as fixed objectives. This paper describes the rationale for abandoning a priori assessment of the acceptability of earthquake consequences as conceived in consequence-based engineering (CBE). Support for an alternative approach comes from behavioral and policy research including an examination of seismic retrofit decision processes for U.S. General Services Administration-owned federal buildings. Additional review of research on earthquake mitigation policy making at the local government level also supports the case. We then suggest dynamic decision structuring that would better support the integration of engineering expertise and decision makers’ preferences.
Which Spectral Acceleration are you Using?
Authors: Baker Jack W. , Cornell C. Allin
Published: May 2006

Analysis of the seismic risk to a structure requires assessment of both the rate of occurrence of future earthquake ground motions (hazard) and the effect of these ground motions on the structure (response). These two pieces are often linked using an intensity measure such as spectral acceleration. However, earth scientists typically use the geometric mean of the spectral accelerations of the two horizontal components of ground motion as the intensity measure for hazard analysis, while structural engineers often use spectral acceleration of a single horizontal component as the intensity measure for response analysis. This inconsistency in definitions is typically not recognized when the two assessments are combined, resulting in unconservative conclusions about the seismic risk to the structure. The source and impact of the problem is examined in this paper, and several potential resolutions are proposed. This discussion is directly applicable to probabilistic analyses, but also has implications for deterministic seismic evaluations.
Seismic Evaluation of Low-Rise Reinforced Masonry Buildings with Flexible Diaphragms: III. Synthesis and Application
Authors: Cohen Gregory L. , Klingner Richard E. , Hayes John R. , Sweeney Steven C.
Published: May 2006

This paper outlines the last two phases of a joint research study performed by the University of Texas at Austin and the U.S. Army Corp of Engineers, Construction Engineering Research Laboratory, Engineer Research and Development Center (CERL). The study coordinates and synthesizes experimental testing, analytical modeling, practical implementation, and real-world application to enhance FEMA-310, the predominant seismic evaluation methodology for low-rise reinforced masonry buildings with flexible diaphragms. In earlier phases of study, conclusions from shaking-table testing, quasi-static testing, and analytical modeling were used to develop a simple tool for the seismic analysis of these types of buildings. In this paper, the tool is developed in the context of performance-based earthquake engineering into a supplementary evaluation methodology intended to fill a gap in FEMA-310. The tool is applied to four existing buildings and ultimately shown to be simple, useful, and necessary.
Modeling Community Recovery from Earthquakes
Authors: Miles Scott B. , Chang Stephanie E.
Published: May 2006

This paper sets out the foundations for developing robust models of community recovery from earthquake disasters. Models that anticipate post-disaster trajectories are complementary to loss estimation models that predict damage and loss. Such models can serve as important decision support tools for increasing community resilience and reducing disaster vulnerability. The paper first presents a comprehensive conceptual model of recovery. The conceptual model enumerates important relationships between a community's households, businesses, lifeline networks, and neighborhoods. The conceptual model can be operationalized to create a numerical model of recovery. To demonstrate this, we present a prototype computer simulation model and graphical user interface. As the model is intended for decision support, it is important to involve potential users in model development. We conducted a focus group involving Puget Sound, Washington, area disaster management practitioners to elicit local insight about community recovery and model development needs, using the prototype as stimulus. Important focus group issues included potential model inputs, useful recovery indicators, potential uses of recovery models, and suitable types of software systems.
Value of Injuries in the Northridge Earthquake
Authors: Porter Keith , Shoaf Kim , Seligson Hope
Published: May 2006

The economic equivalent value of deaths and injuries in the 1994 Northridge earthquake has not previously been calculated, although number of injuries by category of treatment has. Using dollar-equivalent values for injuries accepted and used by the U.S. government for evaluating the cost-effectiveness of risk-mitigation efforts, the value of injuries in the 1994 Northridge earthquake is estimated to be $1.3 to 2.2 billion in 1994 (90% confidence bounds, equivalent to $1.8 to 2.9 billion in 2005). This is equivalent to 3–4% of the estimated $50 billion (in 1994) estimated direct capital losses and direct business interruption losses. If injuries in the 1994 Northridge earthquake are representative of injuries in future U.S. events, then the economic value of future earthquake injuries—the amount that the U.S. government would deem appropriate to expend to prevent all such injuries—is on the order of $200 million per year (in 2005 constant dollars). Of this figure, 96% is associated with nonfatal injuries, an issue overlooked by current experimental research. Given the apparently high cost of this type of loss, this appears to represent an important gap in the present earthquake research agenda.
A Simplified Method for Estimating the Amount of Energy Dissipated by Flexure-Dominated Reinforced Concrete Members for Moderate Cyclic Deformations
Authors: Park Honggun , Eom Taesung
Published: May 2006

In advanced earthquake analysis/design methods, the cyclic behavior of reinforced concrete (RC) members, which is characterized by strength, deformability, and the amount of dissipated energy, must be estimated with reasonable precision. However, presently, the amount of dissipated energy is estimated by either empirical equations, which are not sufficiently accurate, or experiments and sophisticated numerical analysis, which are difficult to use in practice. In the present study, nonlinear finite element analysis was performed to investigate the behavioral characteristics of flexure-dominated RC members subject to moderate plastic displacements. The results showed that flexural pinching can occur due to the effects of axial compressive force and asymmetrical rebar arrangement. However, axial force has little effect on the energy dissipation. The arrangement and ratio of reinforcement have substantial effects. Based on the findings, a simplified method to estimate the energy dissipated by flexure-dominated members was developed, and was verified by comparing its results with those of existing experiments on beams, columns, and structural walls.
Nisqually Earthquake Electric Utility Analysis
Authors: Park Jaewook , Nojima Nobuoto , Reed Dorothy A.
Published: May 2006

The performance of an urban electric utility distribution system was evaluated for the February 2001 Nisqually earthquake. The restoration rate of the lifeline following the event was determined; the distribution of outage durations was estimated; and correlations between lifeline damage and instrumental Modified Mercalli intensity, peak ground velocity, and peak ground acceleration values were ascertained using a GIS (geographical information systems) approach. Using a logit regression analysis, a fragility curve was developed for the lifeline in a manner similar to O'Rourke's formulation of water-line performance (O'Rourke et. al. 2000). Extrapolation of the model to the Seattle Fault earthquake scenario was made to demonstrate its feasibility for prediction.
Methodology for Site Classification Estimation Using Strong Ground Motion Data from the Chi-Chi, Taiwan, Earthquake
Authors: Phung Vietanh , Atkinson Gail M. , Lau David T.
Published: May 2006

The ground motions of the Chi-Chi, Taiwan, earthquake ( Mw=7.6) were recorded at 420 strong-motion stations, including 69 near-fault sites. However, the site conditions of many stations are not available. Among 420 strong-motion stations, the site conditions are known for only 87 stations, which were classified into four groups ( S1, S2, S3, and S4) by using borehole data and some surface geology. This paper presents a methodology to estimate the missing site condition information at strong-motion stations in Taiwan. The method is based on the shape of the 5% damped pseudo-acceleration spectrum of the horizontal ground motion component normalized with respect to average PGA, where the classification scheme is developed using the data from the 87 stations for which the site conditions are known. Possible effects of soil nonlinearity, and distance to the fault on the classification are investigated. The results obtained from the proposed methodology are well correlated with the available known site classification information data. The methodology is then applied to estimate the site condition for the other 333 stations without known site classification. Our results are compared to previous results obtained based on interpretation of geologic maps and geomorphologic data. We find that the two approaches agree in 71% of the cases. We also tested the horizontal-to-vertical spectral ratio technique to estimate the site classification of other 333 strong-motion stations. However, this technique resulted in lower accuracy than does the proposed technique based on the spectral shape of normalized response spectra.
HER-2 Is an Independent Prognostic Factor in Endometrial Cancer: Association With Outcome in a Large Cohort of Surgically Staged Patients
Authors: Morrison Carl , Zanagnolo Vanna , Ramirez Nilsa , Cohn David E. , Kelbick Nicole , Copeland Larry , Maxwell Larry G. , Fowler Jeffrey M.
Published: May 2006

Purpose

To evaluate HER-2 expression and amplification in a large cohort of endometrial cancer with complete surgical staging and outcome data.

Patients and Methods

A tissue microarray was constructed of 483 patients with endometrial cancer of diverse histologic type and stage and tested for HER-2 expression and amplification using current standards of practice. There was outcome data for 83% of all patients and 81% with complete surgical staging.

Results

Both expression and amplification of HER-2 was associated with high-grade (P = .0001) and high stage (P = .0001) endometrial cancer. The highest rate of HER-2 expression and amplification was seen in serous carcinoma (43% and 29%), while grade 1 endometrioid adenocarcinoma showed the lowest levels (3% and 1%). For all histologic types, the rate of HER-2 expression and amplification was remarkably different (P < .0001) for grade 3 cancers (31% and 15%) versus grade 2 (7% and 3%) and grade 1 cancers (3% and 1%), with similar results for endometrioid type (P < .0001). Both HER-2 expression and amplification correlated with disease-specific survival and progression-free survival in univariate analyses. By multivariate analysis HER-2 expression in the presence of amplification (P = .012) correlated with overall survival, but not expression in the absence of amplification. Overall survival was significantly shorter (P = .0001) in patients who overexpressed (median, 5.2 years) and/or showed amplification of HER-2 (median, 3.5 years) versus those that did not (median of all cases, 13 years).

Conclusion

Our results would suggest that HER-2 is an important oncogene in high grade and stage endometrial cancer, but plays only a minor role in the much more common low grade and stage tumors that encompass the majority of clinical practice.
Is the Brain a Quantum Computer?
Authors: Litt Abninder , Eliasmith Chris , Kroon Frederick W. , Weinstein Steven , Thagard Paul
Published: May 2006

We argue that computation via quantum mechanical processes is irrelevant to explaining how brains produce thought, contrary to the ongoing speculations of many theorists. First, quantum effects do not have the temporal properties required for neural information processing. Second, there are substantial physical obstacles to any organic instantiation of quantum computation. Third, there is no psychological evidence that such mental phenomena as consciousness and mathematical thinking require explanation via quantum theory. We conclude that understanding brain function is unlikely to require quantum computation or similar mechanisms.
Molecular Cloning, Tissue Distribution, and Ontogenic Thyroidal Expression of the Chicken Thyrotropin Receptor
Authors: Grommen Sylvia V. H. , Taniuchi Shusuke , Janssen Tom , Schoofs Liliane , Takahashi Sumio , Takeuchi Sakae , Darras Veerle M. , De Groef Bert
Published: May 2006

TSH and the interaction with its receptor (TSHR) in the thyroid gland play a crucial role in the pituitary-thyroid axis of all vertebrates. Released upon stimulation by TSH, thyroid hormones influence numerous processes in the body and are extremely important during the last week of chicken embryonic development. In this study, we have cloned and functionally characterized the chicken TSHR (cTSHR), which was found to be a G protein-coupled receptor consisting of 10 exons. Besides the full-length cDNA, we detected two splice variants lacking either exon 3, or exons 2 and 3, both part of the extracellular domain of the receptor. Bovine TSH increased intracellular cAMP levels in HEK-239 cells transiently expressing the full-length cTSHR (EC50 = 1.43 nm). In situ hybridization showed the expression of cTSHR mRNA in the thyroidal follicular cells. cTSHR mRNA expression, as determined by real-time PCR, was also found in several other tissues such as brain, pituitary, pineal gland, and retina, suggesting that the TSH-TSHR interaction is not only important in regulating thyroid function. TSHR mRNA expression in the thyroid gland did not change significantly during the last week of embryonic development, which suggests that an increased thyroidal sensitivity is not part of the cause of the concomitant increasing T4 levels.
Klotho Protein Promotes Adipocyte Differentiation
Authors: Chihara Yukana , Rakugi Hiromi , Ishikawa Kazuhiko , Ikushima Masashi , Maekawa Yoshihiro , Ohta Junsuke , Kida Iwao , Ogihara Toshio
Published: May 2006

Mice with homozygous disruption of the klotho exhibit multiple age-related disorders and have barely detectable amounts of white adipose tissue. Although klotho expression in cultured adipocytes has been reported, little is known about its function in adipocytes. In the present study, we investigated the role of klotho on adipocyte differentiation. Adipocyte differentiation was induced by incubation of confluent 3T3-L1 cells with insulin, dexamethasone, and 1-methyl-3-isobutyl-xanthin. Klotho-siRNA and expression vector were produced for klotho suppression and overexpression, respectively. Klotho protein was purified for determination of the hormonal effect of klotho. Klotho mRNA and protein expression increased up to the 3rd d of differentiation. A peroxisome proliferator-activated receptor-γ agonist increased klotho expression during the early period of adipocyte differentiation. The mRNA expression of adipocyte differentiation markers, such as CCAAT/enhancer-binding protein (C/EBP)α, C/EBPβ, C/EBPδ, peroxisome proliferator-activated receptor-γ, and fatty acid binding protein 4, was decreased by klotho suppression, and increased 1.9- to 3.8-fold by klotho overexpression. The results of Oil Red O staining also suggested that klotho overexpression promoted adipocyte differentiation. Klotho protein stimulation resulted in a 2.4- to 4.6-fold increase in mRNA expression of differentiation markers compared with control, and the time course depended on adipocyte induction status. Western blot analysis showed that protein levels of C/EBPα and C/EBPδ were increased by Klotho protein stimulation. These results suggest that klotho works as a hormonal factor to promote adipocyte differentiation in the early days, during the period of transient proliferation in the differentiation process, and that klotho may play an essential role in adipocyte differentiation.
Interleukin 11 Signaling Components Signal Transducer and Activator of Transcription 3 (STAT3) and Suppressor of Cytokine Signaling 3 (SOCS3) Regulate Human Endometrial Stromal Cell Differentiation
Authors: Dimitriadis Evdokia , Stoikos Chelsea , Tan Yee-Lee , Salamonsen Lois A.
Published: May 2006

The differentiation of endometrial stromal cells into decidual cells (decidualization) is critical for embryo implantation, but the mechanisms remain poorly defined. Numerous paracrine agents including IL-11 promote human endometrial stromal cell (HESC) decidualization. IL-11 signaling is transduced by the signal transducers and activators of transcription (STAT) proteins. Suppressors of cytokine signaling (SOCS) proteins are stimulated in response to cytokine-inducible STAT phosphorylation, acting in a negative-feedback mechanism to hinder cytokine receptor activity. This study examined the role of IL-11 signal transduction components in HESC decidualization in an ex vivo model. Cells were induced to differentiate with estrogen plus medroxyprogesterone acetate (E+P) or cAMP (assessed by prolactin secretion) and resulted in increased STAT3 and SOCS3. E+P maximally stimulated STAT3, whereas cAMP maximally stimulated SOCS3 during decidualization, suggesting E+P and cAMP differentially regulated the signaling components. IL-11 stimulated the phosphorylation (p) of STAT3 and SOCS3 mRNA and protein. Antiprogestin (onapristone) added to decidualizing cells attenuated STAT3 protein but increased SOCS3 mRNA and protein, suggesting regulation via both ligand-dependent and -independent progesterone-receptor pathways. SOCS3 overexpression in HESC reduced IL-11-induced pSTAT3 and retarded decidualization, indicating that SOCS3 is a critical regulator of differentiation. Immunoreactive pSTAT3 and SOCS3 were all present in decidualized stromal cells, epithelial cells, and leukocytes in human endometrium. These data support a role for IL-11 via pSTAT3 and SOCS3 in initiating and progressing decidualization.
Biological Effect of a Novel Mutation in the Third Leucine-Rich Repeat of Human Luteinizing Hormone Receptor
Authors: Leung Michael Yiu-Kwong , Steinbach Peter J. , Bear Deborah , Baxendale Vanessa , Fechner Patricia Y. , Rennert Owen M. , Chan Wai-Yee
Published: May 2006

A novel heterozygous mutation A340T leading to the substitution of Phe for the conserved amino acid Ile114 was identified by nucleotide sequencing of the human LH/chorionic gonadotropin receptor (hLHR) of a patient with Leydig cell hypoplasia. This mutation is located in the third leucine-rich repeat in the ectodomain of the hLHR. In vitro expression studies demonstrated that this mutation results in reduced ligand binding and signal transduction of the receptor. Studies of hLHR constructs in which various amino acids were substituted for the conserved Ile114 showed that receptor activity is sensitive to changes in size, shape, and charge of the side chain. A homology model of the wild-type hLHR ectodomain was made, illustrating the packing of conserved hydrophobic side chains in the protein core. Substitution of Ile114 by Phe might disrupt intermolecular contacts between hormone and receptor. This mutation might also affect an LHR-dimer interaction. Thus, the I114F mutation reduces ligand binding and signal transduction by the hLHR, and it is partially responsible for Leydig cell hypoplasia in the patient.
The energetic costs of trunk and distal-limb loading during walking and running in guinea fowlNumida meleagris
Authors: Ellerby David J. , Marsh Richard L.
Published: May 2006

We examined the changes in muscle energy use in guinea fowl running at 1.5 m s-1 either unloaded, or carrying trunk loads equal to 23% of body mass, or loads on their distal legs equal to a total of 5% of body mass. We estimated muscle energy use by measuring blood flow to all of the leg muscles using injected microspheres. Total blood flow to the leg muscles increased by approximately 15% under both loading conditions, which matched the percentage increase in net organismal metabolic rate. Significant increases in energy use(inferred from blood flow) above that found in unloaded birds were found in 12 muscles in trunk-loaded birds, with most of the increases restricted to stance-phase muscles, as predicted. Just three of these muscles, the femerotibialis, the iliotibialis lateralis pars postacetabularis and the fibularis longus accounted for 70% of the increased energy use. Noticeably absent from the group of muscles that increased energy use during trunk loading were several large biarticular muscles that have extensor actions at the hip or ankle, but flexor actions at the knee. We concluded that the low energetic cost of carrying trunk loads in guinea fowl may rely on the activation of a group of muscles that together provide support and propulsion across all the major joints, without producing opposing moments at other joints that could potentially waste energy. The specific leg muscles responsible for the increase in metabolism during trunk loading also suggest that the energy cost of producing mechanical work may be an important determinant of the cost of carrying extra mass on the trunk. During distal-limb loading, eleven leg muscles had significant increases in energy use, but unlike during trunk loading, both stance- and swing-phase muscles had large increases in energy use. This distribution of energy use between stance and swing agrees with the prediction that increased mechanical work determines the cost of limb loading, because a substantial fraction of the increased segmental work during distal-limb loading in guinea fowl has been found to occur during stance.
Personal Taxes, Endogenous Default, and Corporate Bond Yield Spreads
Authors: Liu Sheen X. , Qi Howard , Wu Chunchi
Published: May 2006

Term structure models have often been criticized for failing to explain satisfactorily the yield spread between corporate and Treasury bonds. A potential problem is that the personal tax effect is ignored in these models. In this paper, we employ a structural model to investigate the role of personal taxes on both debt and equity returns in capital structure decisions and assess their impact on corporate bond yield spreads. It is shown that personal taxes affect the firm’s optimal capital structure, and the tax premium explains a substantial portion of yield spreads, especially for high-grade bonds. The predictive ability of the model for yield spreads is much improved when personal tax effects are accounted for. In controlling for the liquidity effect, we obtain implied personal income tax rates closely in line with Graham’s (1999) estimates.
Reclaiming Quasi–Monte Carlo Efficiency in Portfolio Value-at-Risk Simulation Through Fourier Transform
Authors: Jin Xing , Zhang Allen X.
Published: May 2006

Quasi–Monte Carlo methods overcome the problem of sample clustering in regular Monte Carlo simulation and have been shown to improve simulation efficiency in the derivatives pricing literature when the price is expressed as a multidimensional integration and the integrand is suitably smooth. For portfolio value-at-risk (VaR) problems, the distribution of portfolio value change is based on the expectation of an indicator function, hence the integrand is discontinuous. The purpose of this paper is to smooth the expectation estimation of an indicator function via Fourier transform so that the faster convergence rate of quasi–Monte Carlo methods can be reclaimed theoretically. Under fairly mild assumptions, the simulation of portfolio value-at-risk is fast and accurate. Numerical examples elucidate the advantage of the proposed approach over regular Monte Carlo and quasi–Monte Carlo methods.
Histochemical and Electron Microscopic Analysis of Spiculogenesis in the Demosponge Suberites domuncula
Authors: Eckert Carsten , Schröder Heinz C. , Brandt David , Perovic-Ottstadt Sanja , Müller Werner E.G.
Published: May 2006

The skeleton of demosponges is built of spicules consisting of biosilica. Using the primmorph system from Suberites domuncula, we demonstrate that silicatein, the biosilica-synthesizing enzyme, and silicase, the catabolic enzyme, are colocalized at the surface of growing spicules as well as in the axial filament located in the axial canal. It is assumed that these two enzymes are responsible for the deposition of biosilica. In search of additional potential structural molecules that might guide the mineralization process during spiculogenesis to species-specific spicules, electron microscopic studies with antibodies against galectin and silicatein were performed. These studies showed that silicatein forms a complex with galectin; the strings/bundles of this complex are intimately associated with the surface of the spicules and arranged concentrically around them. Collagen fibers are near the silactein/galectin complexes. The strings/bundles formed from silicatein/galectin display a lower degree of orientation than the collagen fibers arranged in a highly ordered pattern around the spicules. These data indicate that species-specific formation of spicules involves a network of (diffusible) regulatory factor(s) controlling enzymatic silica deposition; this mineralization process proceeds on a galectin/collagen organic matrix.
Liquid Chromatography–Tandem Mass Spectrometry for Detection of Low Concentrations of 21 Benzodiazepines, Metabolites, and Analogs in Urine: Method with Forensic Applications
Authors: Quintela Oscar , Sauvage François-Ludovic , Charvier Fabienne , Gaulier Jean-Michel , Lachâtre Gérard , Marquet Pierre
Published: May 2006

Background: Commonly used methods for detecting benzodiazepines (BZPs) and BZP-like substances, such as zolpidem and zopiclone, may not detect low concentrations of these drugs. We developed a liquid chromatographic–tandem mass spectrometric method for identifying these drugs and their relevant metabolites.

Methods: We extracted BZPs from urine by solid-phase extraction with a mixed-mode phase (OASIS® HLB cartridges). Chromatographic separation was performed with a Waters XTerra MS C18 [150 × 2.1 mm (i.d.); bead size, 5 μm] reversed-phase column with deuterated analogs of the analytes as internal standards (IS). Detection was performed with a triple-quadruple mass spectrometer that monitored 2 specific transitions per compound in the electrospray, positive-ion selected-reaction monitoring mode. We tested this technique on urine samples from 12 healthy volunteers and 1 forensic sample obtained in a case of alleged drug-facilitated sexual assault.

Results: Chromatographic separation was achieved within 18 min. The linear dynamic ranges extended from 0.02 or 0.1 μg/L (depending on the drug or metabolite) to 50 μg/L. Extraction recovery (range) was 77%–110%. Limits of detection were ≤0.05 μg/L. No ion suppression was seen except for alprazolam, for which baseline decreased by almost 20%. In the forensic urine sample, the method detected alprazolam (3.5 μg/L) and its characteristic metabolite, α-hydroxyalprazolam (0.17 μg/L).

Conclusion: This method measured low concentrations of BZPs and BZP-like substances and might be useful for analyses of urine in suspected drug-facilitated sexual assault cases.
High Lipoprotein-Associated Phospholipase A2 Is a Risk Factor for Recurrent Coronary Events in Postinfarction Patients
Authors: Corsetti James P , Rainwater David L , Moss Arthur J , Zareba Wojciech , Sparks Charles E
Published: May 2006

Background: Recent studies demonstrate that lipoprotein-associated phospholipase A2 (Lp-PLA2) is a risk factor for cardiovascular disease presumably deriving from generation of proinflammatory and proatherogenic species through its hydrolytic activity on lipoprotein-associated phospholipids. The goal of this study was to assess the relationship of Lp-PLA2 with a set of thrombogenic, lipid, inflammatory, and metabolic blood markers and to determine whether plasma Lp-PLA2 is a risk factor for recurrent coronary events in postinfarction patients.

Methods: Factor analysis on the set of blood markers and Lp-PLA2 was performed for 766 patients of the Thrombogenic Factors and Recurrent Coronary Events (THROMBO) postinfarction study. Recurrent coronary event risk was assessed as a function of blood marker concentrations and Lp-PLA2 by Cox proportional hazards multivariable regression adjusted for significant clinical covariates.

Results: Factor analysis revealed that Lp-PLA2 was associated with one factor dominated by cholesterol and apolipoprotein B and another factor dominated by HDL-cholesterol and triglycerides, with little association with an inflammatory factor dominated by C-reactive protein. Multivariable analysis demonstrated as significant and independent predictors of risk of secondary coronary events only apolipoprotein B in a model without Lp-PLA2 (hazard ratio, 1.66; 95% confidence interval, 1.14–2.40) and only Lp-PLA2 in a model with Lp-PLA2 included [1.90 (1.31–2.75)].

Conclusions: Lp-PLA2 is a significant and independent predictor of risk for recurrent coronary events in postinfarction patients, and Lp-PLA2 is related to both hypercholesterolemia and high triglyceride–low HDL dyslipidemia in this study population.
Diagnosing Inborn Errors of Lipid Metabolism with Proton Nuclear Magnetic Resonance Spectroscopy
Authors: Oostendorp Marlies , Engelke Udo FH , Willemsen Michèl AAP , Wevers Ron A
Published: May 2006

Background: Many severe diseases are caused by defects in lipid metabolism. As a result, patients often accumulate unusual lipids in their blood and tissues, and proper identification of these lipids is essential for correct diagnosis. In this study, we investigated the potential use of proton nuclear magnetic resonance (1H-NMR) spectroscopy to simultaneously identify and quantify (un)usual lipids present in the blood of patients with different inborn errors of lipid metabolism.

Methods: We extracted blood plasma or serum lipids in chloroform–methanol (2:1 by volume). After addition of the nonvolatile chemical shift and concentration reference compound octamethylcyclotetrasiloxane, we performed 1H-NMR measurements on a 500-MHz spectrometer. Assignments were based on the literature, computer simulations, and reference spectra of relevant authentic standards.

Results: Spectra of normal plasma samples allowed the identification of 9 lipid species. We found good correlation between conventional methods and 1H-NMR for cholesterol and triglyceride concentrations. We also investigated 4 inborn errors of lipid metabolism (3 in sterol metabolism and 1 in fatty acid metabolism). NMR analysis led to a correct diagnosis for all 4 diseases, whereas the concentration of the diagnostic metabolite could be determined for 3.

Conclusions: 1H-NMR spectroscopy of blood plasma or serum lipid extracts can be used to accurately identify and quantify lipids. The method can also identify unusual lipids in the blood of patients with inborn errors of lipid metabolism. This technique may therefore be applicable in clinical diagnosis and follow-up.
GABAergic Network Activation of Glial Cells Underlies Hippocampal Heterosynaptic Depression
Authors: Serrano Alexandre , Haddjeri Nasser , Lacaille Jean-Claude , Robitaille Richard
Published: May 2006

Tetanus-induced heterosynaptic depression in the hippocampus is a key cellular mechanism in neural networks implicated in learning and memory. A growing body of evidence indicates that glial cells are important modulators of synaptic functions, but very little is known about their role in heterosynaptic plasticity. We examined the role of glial cells in heterosynaptic depression, knowing that tetanization and NMDA application caused depression of synaptic field responses (fEPSPs) and induced Ca2+rise in glial cells. Here we report that chelating Ca2+in a glial syncytium interfered with heterosynaptic depression and NMDA-induced fEPSP depression, suggesting that Ca2+activation of glial cells is necessary for heterosynaptic depression. The NMDA-induced Ca2+rise in glial cells was sensitive to tetrodotoxin and reduced by the GABABantagonistCGP55845. Both heterosynaptic depression and simultaneous Ca2+activation of glial cells were prevented byCGP55845, suggesting an involvement of the GABAergic network in glial activation and heterosynaptic depression. Also, the GABABagonist baclofen caused both a Ca2+rise in glial cells and fEPSP depression. Heterosynaptic depression, as well as NMDA- and baclofen-induced depression, were attenuated by an A1antagonist, cyclopentyl-theophylline, whereas glial cell activation was not, indicating a role of adenosine downstream of glial activation. Finally, heterosynaptic depression requires ATP degradation because ectonucleotidase inhibitors reduced this plasticity. Our work indicates that Ca2+activation of glial cells is necessary for heterosynaptic depression, which involves the sequential interaction of Schaffer collaterals, the GABAergic network, and glia. Thus, glial and neuronal networks are functionally associated during the genesis of heterosynaptic plasticity at mammalian central excitatory synapses.
Translation, Migration, and Communication in the Roman Empire: Three Aspects of Movement in History
Authors: Moatti Claudia
Published: May 2006

Abstract This paper isolates movement as a topic for analysis in Roman imperial history. Movement is regarded under three aspects: translation (of texts, practices, ideas), migration (of officials, merchants, students, etc.), and communication (i.e. the movement of written documents). Interrelationships among the three aspects of movement are identified and discussed, as are the shared impact of translation, migration, and communication on issues of cultural and social identity and political negotiation and control. The article argues that movement changes the role of the state as well as relations between individual and states, augments the use of writing in society, transforms identities, and gives impulse to internal and external regulations. The implications of movement are understood as both pragmatic and formal, altering relations to space and time and influencing ways of organizing and thinking. The author surveys current work in the field and identifies potential areas for future research. The paper draws heavily on both literary and documentary sources and discusses material from the late republic through late antiquity, paying particular attention to continuities and discontinuities between early and later periods of the Roman empire.
Educating Croesus: Talking and Learning in Herodotus' Lydian {Logos
Authors: Pelling Christopher
Published: May 2006

Abstract Two themes, the elusiveness of wisdom and the distortion of speech, are traced through three important scenes of Herodotus' Lydian logos, the meeting of Solon and Croesus (1.29–33), the scene where Cyrus places Croesus on the pyre (1.86–90), and the advice of Croesus to Cyrus to cross the river and fight the Massagetae in their own territory (1.207). The paper discusses whether Solon is speaking indirectly at 1.29–33, unable to talk straight to Croesus about his transgressive behavior: if so, that illuminates the dynamics of speech at a court. At 1.86–90 Croesus may not have fully understood what Solon earlier said to him. Cyrus may understand Croesus' report of Solon's words better than Croesus does himself. Herodotus' readers will also be uncertain what the response of Delphi will be to Croesus' indignant questioning: if a reader has failed to grasp the significance of Gyges' transgression five generations earlier, that reenacts the forgetfulness of figures in the text. At 1.207 Croesus' advice to Cyrus is of questionable wisdom: Croesus too cannot speak directly, and he has anyway learned the wrong lesson from his catastrophe, extrapolating too directly from his own experience. The conclusion suggests some reasons why Herodotus should have chosen to begin his History with Lydia, the kingdom that is on the cusp between East and West, and with Croesus, a figure that resists description in the easy formulations of Greek/barbarian discourse.
History, Metahistory, and Audience Response in Livy 45
Authors: Levene D. S.
Published: May 2006

Abstract The paper studies Livy's account in Book 45 of the aftermath of Aemilius Paullus' conquest of Macedon employing two interpretative methods, both common in recent studies of historians. The first is “metahistory,” in other words interpreting events within a historical narrative as commenting covertly on the genre of history and on the work as an example of that genre. The second is seeing how internal audiences provide a guide for the reader's interpretation. These, though theoretically independent, are in practice often related, with internal audiences being used as a trigger for wider reflections on the text and the genre. Four linked passages from Livy 45 are discussed in detail. One (Aemilius' tour of Greece) invites a systematic metahistorical reading without the use of an internal audience, partly to endorse Livy's own manner of “secondary” history, partly to promote a moral reading of the text. The other three employ internal audiences to similar effect: first, Aemilius' meeting with the defeated Perseus, and the lesson which he draws about the mutability of fortune; second, the spectacular games he organizes at Amphipolis; and third, his eventual triumph in Rome, along with the speech that Servilius gives in its support. The understanding of the genre of history that Livy promotes through these passages is, however, astonishingly narrow and didactic, ignoring even central aspects of his own work which do not conform to that understanding. The paper concludes by considering why Livy would wish to present himself and his genre as single-mindedly moralistic when neither he nor it actually was.
Content Validity and Reliability Testing of the FIN-PED II: A Tool to Measure Care Needs of Parents of Children With Cancer
Authors: Monterosso Leanne , Kristjanson Linda J. , Dadd Gaye
Published: May 2006

This study tested the reliability and validity of the refined Family Inventory of Needs-Pediatrics (FIN-PED), the FIN-PED II, a 17-item instrument structured to measure care needs of parents of children with cancer. The instrument comprises three rating scales. The first rating scale measures the importance-of-care needs, the second measures the extent to which needs are met, and the third measures the need for further information. The revised instrument was first pilot tested with an expert panel of three mothers and three fathers of children with cancer who rated the tool for clarity, apparent internal consistency, and content validity. All items met preset criteria for these assessments. The instrument was then mailed to 85 parents of Australian children with cancer and tested for internal consistency reliability and test-retest reliability. Thirty-four parents returned the instrument. All three rating scales achieved high estimates of internal consistency. Evidence of the instrument’s stability over time was also achieved. This study provided support for the reliability and content validity of the FIN-PED II.
Maternal Sensitivity and Attachment Security in Thailand: Cross-Cultural Validation of Western Measures
Authors: Chaimongkol Nujjaree N. , Flick Louise H.
Published: May 2006

The purpose of this study was to examine the psychometric properties of Thai versions of the Maternal Behavior Q-Sort (MBQS), Caldwell’s HOME, and the Attachment Q-set (AQS). A sample of 110 Thai mother-infant dyads were studied. The Content Validity Index (CVIs) of the Thai MBQS, HOME and AQS were between 91% and 99%. Internal consistency of the HOME was .71. Interobserver reliability of the MBQS, HOME, and AQS were .95, .87, and .87, respectively. Convergent validity was supported by finding a positive correlation between the MBQS and the HOME (r = .29, p < .001). A positive correlation of .45 (p < .001) between the scores of the MBQS and the AQS indicated concurrent validity of these scales. Study findings indicate the Thai MBQS, HOME, and AQS are reliable and valid in this Thai sample and suggest that the Thai versions reflect concepts similar to those in the original English versions.
Managing Reproductive Isolation in Hybrid Seed Corn Production
Authors: Ireland D. S. , Wilson D. O. , Westgate M. E. , Burris J. S. , Lauer M. J.
Published: May 2006

Production of hybrid corn (Zea maysL) depends on cross‐pollination between male and female inbred parents. As such, reproductive isolation of seed fields is required to ensure genetic purity of the hybrid progeny. Customer demand for improved genetic purity prompted the seed industry to examine the level of genetic purity resulting from current isolation practices. A 3‐yr study was conducted to monitor purity of hybrid seed produced in 315 fields from 24 seed companies in North America. Each field was near a commercial corn field shedding pollen synchronously with the seed parent: a worse case scenario. Seed samples were collected at five locations along a 200‐m transect established perpendicular to the nearest potential adventitious pollen source, and 100 seed from each location were subjected to isozyme analysis to determine percent out‐crossing. Isolation distance, seed field size, field block size, number of border rows, adventitious field size, male:female row ratio, male population, and male pollen class were analyzed as continuous predictors and as variable class predictors of out‐crossing at the field margins and field midpoints. Year had a significant (p≤ 0.05) impact on observed out‐crossing. Isolation distance, border rows, and male pollen class were significant predictors of out‐crossing at the field margin but not at the field midpoint. A significant interaction between isolation distance and border rows was observed at both the field margin and midpoint. There also was an interaction between male:female ratio and male pollen class on out‐crossing at the field margin. These results indicate that current practices used to isolate hybrid seed fields often achieve the goal of producing ≥99% genetically pure seed, but much higher levels of out‐crossing can and do occur. Because out‐crossing generally was greater and more variable at the field margins than at the field midpoint, adjustments to field management that focus on minimizing out‐crossing at the field margins should lead to consistently high levels of genetic purity from hybrid seed fields.