bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exposure misclassification: bias in category specific Poisson regression coefficients
Authors: Veierød Marit B. , Laake Petter 
Published: September 2002

AbstractIn epidemiologic studies of the association between exposure and disease, misclassification of exposure is common and known to induce bias in the effect estimates. The nature of the bias is difficult to foretell. For this purpose, we present a simple method to assess the bias in Poisson regression coefficients for a categorical exposure variable subject to misclassification. We derive expressions for the category specific coefficients from the regression on the error‐prone exposure (naive coefficients) in terms of the coefficients from the regression on the true exposure (true coefficients). These expressions are similar for crude and adjusted models, if we assume that the covariates are measured without error and that it is independence between the misclassification probabilities and covariate values. We find that the bias in the naive coefficient for one category of the exposure variable depends on all true category specific coefficients weighted by misclassification probabilities. On the other hand, misclassification of an exposure variable does not induce bias in the estimates of the coefficients of the (perfectly measured) covariates. Similarities with linear regression models are pointed out. For selected scenarios of true exposure–disease associations and selected patterns of misclassification, we illustrate the inconsistency in naive Poisson regression coefficients and show that it can be difficult to intuitively characterize the nature of the bias. Both the magnitude and the direction of the bias may vary between categories of an exposure variable. Copyright © 2001 John Wiley & Sons, Ltd.
A closer look at combining data among a small number of binomial experiments
Authors: Malec Donald 
Published: September 2002

AbstractIn a regulatory environment, the regulators and the regulated may not be able to agree on the use of subjective prior information for a clinical trial. The use of a data‐based prior offers a greater possibility for agreement, however, the degree of importance given to the prior data may still be contentious. The use of a hierarchical model to link the prior data and the current trial is shown to provide a relatively objective method for assigning weight to the prior data. Using a series of examples combining two binomial experiments, the effect of a hierarchical model on estimating rates, on the degree to which data is combined and on hypothesis testing is illustrated. In addition, the phenomenon in which combining data reduces the precision is explained. Simpler models based on finite mixtures of beta distributions are shown to work as well as the more computationally intensive, continuous mixtures. Lastly, an example combining three concurrent studies is illustrated. Published in 2001 by John Wiley & Sons, Ltd.
Randomization at the level of primary care practice: use of pre‐intervention data and random effects models
Authors: Nixon R. M. , Duffy S. W. , Fender G. R. K. , Day N. E. , Prevost T. C. 
Published: September 2002

AbstractThe Anglia menorrhagia education study tests the effectiveness of an education package for the treatment of menorrhagia given to doctors at a primary care level. General practices were randomized to receive or not receive the package. It is hoped that this intervention will reduce the proportion of women suffering from menorrhagia that are referred to hospital. Data are available on the treatment and referral of women in the practices in the education and control groups, both pre‐ and post‐intervention. We define and demonstrate a random effects logistic regression model that includes pre‐intervention data for calculating the effectiveness of the intervention. Copyright © 2001 John Wiley & Sons, Ltd.
A concept‐oriented belief revision approach to domain knowledge recovery from source code
Authors: Li Yang , Yang Hongji , Chu William 
Published: September 2002

AbstractDomain knowledge is the soul of software systems. After decades of software development, domain knowledge has reached a certain degree of saturation. The recovery of domain knowledge from source code is beneficial to many software engineering activities, in particular, software evolution. In the real world, the ambiguous appearance of domain knowledge embedded in source code constitutes the biggest barrier to recovering reliable domain knowledge. In this paper, we introduce an innovative approach to recovering domain knowledge with enhanced reliability from source code. In particular, we divide domain knowledge into interconnected knowledge slices and match these knowledge slices against the source code. Each knowledge slice has its own authenticity evaluation function which takes the belief of the evidence it needs as input and the authenticity of the knowledge slice as output. Moreover, the knowledge slices are arranged to exchange beliefs with each other through interconnections, i.e. concepts, so that a better evaluation of the authenticity of these knowledge slices can be obtained. The decision on acknowledging recovered knowledge slices can therefore be made more easily. Our approach, rooted as it is in cognitive science and social psychology, is also widely applicable to other knowledge recovery tasks. Copyright © 2001 John Wiley & Sons, Ltd.
Futures thinking by middle managers: a neglected necessity
Authors: Sales Michael 
Published: September 2002

AbstractSystemic forces result in chronic underutilization of the knowledge and insight of middle management. This hypothesis is explored through a case study, which recounts both the efforts of a group of technical managers to affect R&D policy and staffing in their company and the negative reaction of their superiors to this initiative. The management group used various ‘futures thinking’ technologies as a backdrop to their proposals and these are described. The case data are then interpreted through the lens of Barry Oshry's organizational theory, with a particular focus on the difficulties of acting in a concerted fashion from the ‘middle’ of an organization. Some of Oshry's antidotes to the organizational pathologies impacting middle managers are discussed, including recommendations for executives who want to deploy their subordinates strategically. Copyright © 2002 John Wiley & Sons, Ltd.
Chronic cocaine increases κ‐opioid receptor density: Lack of effect by selective dopamine uptake inhibitors
Authors: Collins Stephanie L. , Kunko Paul M. , Ladenheim Bruce , Cadet Jean‐Lud , Carroll F. Ivy , Izenwasser Sari 
Published: September 2002

AbstractContinuous infusion of cocaine or the selective dopamine uptake inhibitors GBR 12909 or RTI‐117 increases locomotor stimulation, to which partial tolerance occurs. In addition, all three drugs produce significant decreases in tyrosine hydroxylase immunoreactivity in caudate putamen and nucleus accumbens core, suggesting a decreased dopaminergic tone. An interaction between cocaine and opioids has long been documented. Chronic cocaine significantly increases μ‐ and κ‐opioid receptors and treatment with a κ‐opioid agonist markedly reduces the behavioral effects of cocaine. In addition, chronic cocaine, but not GBR 12909, increases prodynorphin gene expression in caudate putamen. To further understand the interaction between cocaine and the κ‐opioid system, the effects of a chronic continuous infusion for 14 days of cocaine or one of the selective dopamine uptake inhibitors GBR 12909 or RTI‐117 via osmotic minipump were examined on κ‐opioid receptors using the selective κ‐opioid ligand [3H] U‐69593. [3H] U‐69593 binding density was significantly increased in caudate putamen, nucleus accumbens shell, claustrum, and endopiriform nucleus after cocaine, while neither GBR 12909 nor RTI‐117 had any effect. The increased κ‐opioid receptor densities observed following cocaine are likely not related to dopamine uptake inhibition, since they were not produced by selective dopamine uptake inhibitors. These findings suggest that regulation of κ‐opioid receptors by cocaine may be via inhibition of serotonin or norepinephrine uptake, by a combination of effects on two or three monoamine transporters, or by a mechanism unrelated to transporter inhibition. Synapse 45:153–158, 2002. © 2002 Wiley‐Liss, Inc.
Repeated ventral tegmental area amphetamine administration alters dopamine D1 receptor signaling in the nucleus accumbens
Authors: Hu Xiu‐Ti , Koeltzow Timothy E. , Cooper Donald C. , Robertson George S. , White Francis J. , Vezina Paul 
Published: September 2002

AbstractNeuroadaptations of the mesoaccumbens dopamine (DA) system likely underlie the emergence of locomotor sensitization following the repeated intermittent systemic administration of amphetamine (AMPH). In the nucleus accumbens (NAc), such neuroadaptations include enhanced DA overflow in response to a subsequent AMPH challenge as well as increased sensitivity to the inhibitory effects of D1 DA receptor (D1R) activation and an altered profile of D1R‐dependent induction of immediate early genes (IEGs). Previous results indicate that AMPH acts in the ventral tegmental area (VTA) to initiate those changes leading to sensitization of the locomotor activity and NAc DA overflow produced by systemic administration of this drug. These observations are intriguing, given that acute infusion of AMPH into the VTA does not stimulate locomotor activity or, as we report presently, increase extracellular NAc DA concentrations. Two experiments, therefore, assessed the ability of repeated VTA AMPH to produce adaptations in D1R signaling in the NAc. Rats were administered three bilateral VTA infusions of saline or AMPH (2.5 μg/0.5 μl/side, one every third day). In the first experiment, in vivo extracellular electrophysiological recordings revealed that previous exposure to VTA AMPH enhanced the sensitivity of NAc neurons to the inhibitory effects of iontophoretic application of the D1R agonist SKF 38393. This effect was observed early (2–3 days) and at 1 month of withdrawal, but not after 2 months. Similarly, in the second experiment it was found that the D1R‐dependent induction by AMPH of Fos, FosB, and JunB, but not NGFI‐A, in the NAc was enhanced in rats exposed 1 week earlier to repeated VTA AMPH. These findings indicate that repeated VTA AMPH administration initiates relatively long‐lasting adaptations in D1R signaling in the NAc that may, together with presynaptic adaptations affecting DA overflow, contribute to the expression of locomotor sensitization by this drug. Synapse 45:159–170, 2002. © 2002 Wiley‐Liss, Inc.
5‐HT6 receptor binding sites in schizophrenia and following antipsychotic drug administration: Autoradiographic studies with [125I]SB‐258585
Authors: East Simon Z. , Burnet Philip W.J. , Leslie Ronald A. , Roberts Jennifer C. , Harrison Paul J. 
Published: September 2002

AbstractThe 5‐hydroxytryptamine (5‐HT; serotonin)‐6 receptor (5‐HT6R) is a putative target of atypical antipsychotic drugs and its mRNA expression is altered in schizophrenia. [125I]SB‐258585 is a selective 5‐HT6R antagonist which has been well characterized for use in the rat brain. The present study evaluated its suitability for receptor autoradiography in the human brain and its application to quantitative studies. The affinity (Kd ∼1.2 nM) and relative distribution of binding sites (striatum ≫ cortex ∼ hippocampus) were similar to the rat. The distribution of [125I]SB‐258585 binding in these regions was also consistent with that of 5‐HT6R mRNA, determined in parallel using in situ hybridization. [125I]SB‐258585 binding site densities were measured in dorsolateral prefrontal cortex of 20 patients with chronic schizophrenia and compared with 17 normal subjects. No differences were seen between groups. Neither were [125I]SB‐258585 binding site densities affected in the frontal cortex or striatum of rats following 2 weeks' administration of the antipsychotic drugs haloperidol, chlorpromazine, olanzapine, risperidone, or clozapine. In summary, [125I]SB‐258585 is a suitable radioligand for studies of human brain 5‐HT6R binding sites and shows that their distribution is broadly similar to that of the rodent. The lack of effect of schizophrenia or antipsychotic drug administration on [125I]SB‐258585 binding suggests that an altered receptor density does not contribute to any involvement which the 5‐HT6R may have in the disease or its treatment. Synapse 45:191–199, 2002. © 2002 Wiley‐Liss, Inc.
Prenatal exposure to cocaine reduces the number and enhances reactivity of A10 dopaminergic neurons to environmental stress
Authors: Morrow Bret A. , Elsworth John D. , Roth Robert H. 
Published: September 2002

AbstractPrenatal exposure to cocaine has been shown to result in poor cognitive performance in the resulting offspring in humans and laboratory animals. The underlying biochemical changes that contribute to these behavioral effects are not known but have been proposed to involve changes in dopaminergic function. In these studies, we exposed rats to cocaine in utero using the clinically relevant intravenous model and report a mean loss of 24.8% of the tyrosine hydroxylase immunoreactive, presumed dopaminergic, neurons in the A10, but not A9 and A8, cell groups of the young adult offspring. Additionally, in prenatal cocaine‐exposed rats dopaminergic neurons in the ventral, midline A10, and lateral A9 regions demonstrated a hyperreactivity to environmental stress, as measured by activation of the immediate‐early gene, Fos. Mild, intermittent footshock did not further increase the number of dopamine neurons expressing Fos in prenatal cocaine‐exposed rats, as it did in the prenatal saline controls. Because the exposure to cocaine took place during development, other potential changes in dopaminergic and nondopaminergic neuronal systems could result from the cocaine‐induced reduction in numbers of A10 dopamine neurons. We hypothesize that a perinatal loss of A10 dopamine neurons, and subsequent developmental changes, contributes to a dysregulation of the adult mesoprefrontal system, resulting in the reported cognitive deficits. Synapse 41:337–344, 2001. © 2001 Wiley‐Liss, Inc.
Modulation of voltage‐dependent calcium currents by serotonin in acutely isolated rat amygdala neurons
Authors: Lin Chih‐Hung , Huang Ya‐Chun , Tsai Jing‐Jane , Gean Po‐Wu 
Published: September 2002

AbstractThe modulation of voltage‐dependent calcium currents (ICa) by serotonin (5‐HT) was studied in rat acutely dissociated amygdala neurons using whole‐cell patch‐clamp recording techniques. 5‐HT inhibited ICa in a concentration‐dependent manner with a ED50 of ∼1 μM and a maximal inhibition of ∼50%. The inhibition was mimicked by the selective 5‐HT1A agonist 8‐hydroxy‐dipropylaminotetralin (8‐OH‐DPAT) and was reduced by the 5‐HT1A antagonist NAN‐190, indicating its mediation by 5‐HT1A receptors. Pretreatment of neurons with the alkylating agent N‐ethylmaleimide (NEM) or pertussis toxin (PTX) markedly reduced the action of 5‐HT. The modulation was partially reversed by strong depolarization and was not seen in cell‐attached patches when the agonist was applied outside the recorded patch, suggesting a membrane‐delimited, G‐protein‐mediated signaling pathway. Nimodipine (1 μM) reduced the ICa by ∼30% without reducing inhibition of current by 5‐HT significantly, ruling out L‐type channels as the target of modulation. 5‐HT‐mediated inhibition after exposure to ω‐conotoxin‐GVIA (ω‐CgTX, 1 μM) or ω‐agatoxin‐IV (ω‐AgTX, 200 nM), which blocked 26% and 21% of the total ICa, respectively, was significantly decreased, suggesting involvement of the N‐ and P/Q‐type channels. In the combined presence of ω‐CgTX and ω‐AgTX, 5‐HT still caused a small but significant reduction of ICa, suggesting a possible involvement of R‐type channels. Stimulation of β‐adrenergic receptor with isoproterenol (Iso) or activation of adenylyl cyclase with forskolin resulted in an enhancement of ICa. 5‐HT caused the same degree of inhibition with or without Iso or forskolin pretreatment. On the other hand, application of 8‐OH‐DPAT inhibited ICa and blocked Iso‐ and Sp‐cAMPS‐induced enhancement. These results provide the first evidence showing a dominant effect of 5‐HT‐mediated inhibition over Iso‐mediated enhancement of ICa. Synapse 41:351–359, 2001. © 2001 Wiley‐Liss, Inc.
Spatial distribution and developmental appearance of postjunctional P2X1 receptors on smooth muscle cells of the mouse vas deferens
Authors: Liang Simon Xun , Motin Leonard , Moussa Charbel E.H. , Lavidis Nickolas A. , Phillips William Donald 
Published: September 2002

AbstractP2X1‐type purinoceptors have been shown to mediate fast transmission between sympathetic varicosities and smooth muscle cells in the mouse vas deferens but the spatial organization of these receptors on the smooth muscle cells remains inconclusive. Voltage clamp techniques were used to estimate the amplitudes of spontaneous excitatory junction currents (SEJCs) in cells of the vas deferens longitudinal smooth muscle layer. These currents involved the activation of about 6% of the P2X‐type channels present on the cell, as compared to whole cell currents produced when isolated smooth muscle cells were exposed to maximal concentrations of either ATP or α,β‐MeATP. Immunofluorescence staining of the vas deferens with antibodies against P2X1 receptor showed a diffuse, grainy distribution over the entire membrane of each smooth muscle cell. Anti‐P2X1 staining was not markedly clustered beneath anti‐SV2‐stained sympathetic varicosities. Similar results were obtained for cells in the urinary bladder. During development, P2X1 mRNA was detected as early as embryonic day 15 (E15). Increasing intensities of diffuse immunostaining for P2X1 were observed in the walls of the bladder, tail artery, and aorta from E15 until 6 weeks postnatal. The vas deferens showed increasing intensities of diffuse staining of its smooth muscle layers between 2 and 6 weeks postnatal, consistent with the time‐course of development of fast purinergic transmission described previously. Together, the results suggest that the response of smooth muscle of the vas deferens to ATP released from sympathetic varicosities relies on rapidly desensitizing P2X1 receptors, distributed diffusely across the smooth muscle cell surface. Synapse 42:1–11, 2001. © 2001 Wiley‐Liss, Inc.
GABAergic neurotransmission at the nucleus tractus solitarii in the suppression of reflex bradycardia by parabrachial nucleus
Authors: Len Wen‐Bin , Chan Julie Y.H. 
Published: September 2002

AbstractWe investigated the role of GABAergic neurotransmission at the nucleus tractus solitarii (NTS) in the suppression of cardiac baroreceptor reflex (BRR) response induced by parabrachial nucleus (PBN) complex in adult Sprague‐Dawley rats maintained under pentobarbital anesthesia. Based on in vivo microdialysis coupled with high‐performance liquid chromatography‐fluorescence detection for γ‐aminobutyric acid (GABA), we found that electrical stimulation of the ventrolateral regions and Koelliker‐Fuse (KF) subnucleus of PBN complex resulted in a site‐specific increase in GABA concentration in the dialysate collected from the NTS. The temporal increase in extracellular GABA concentration in the NTS coincided with the time course of PBN‐induced cardiac BRR inhibition. In addition, the PBN‐induced cardiac BRR suppression was reversed by microinjection bilaterally into the NTS of a GABAA receptor antagonist, bicuculline methiodide (5 pmol), or a GABAB receptor antagonist, 2‐OH saclofen (500 pmol). Blockade of neuronal activity in the ventrolateral regions and KF subnucleus of PBN complex with lidocaine (5%) elicited an enhancement of the same reflex response. The time course of this facilitatory effect of lidocaine correlated positively with the temporal decrease in extracellular GABA concentration in the NTS. Anatomically, Fast Blue‐labeled neurons were identified in the same subnuclei of the PBN complex after microinjection of the retrograde transport tracer into the NTS. Some of these Fast Blue‐labeled neurons were also immunoreactive to glutamic acid decarboxylase. These results suggest that a direct GABAergic descending projection from the KF subnucleus and surrounding areas of the PBN complex to the NTS may inhibit cardiac BRR response by activating GABAA and GABAB receptors at the NTS. Synapse 42:27–39, 2001. © 2001 Wiley‐Liss, Inc.
Warping analysis of concrete cores
Authors: Mendis Priyan 
Published: September 2002

AbstractWhen a substantial torsional moment is present, the magnitude of the longitudinal stresses on the core walls due to warping and the header beam forces are quite significant and those actions are too large to be neglected. Many methods developed for warping analysis of concrete cores are either not applicable for complex core structures or difficult to adopt in normal design offices because they are not versatile enough for practical applications. Also, models based on either open sections or completely closed sections may be grossly inaccurate for partially‐closed core sections. A simple method of analysis for estimating the longitudinal stresses on walls and header beam forces for torsionally loaded concrete cores is presented in a manner suitable for use in design offices. In this method, an open section with the header beams is converted to an appropriate continuous continuum through an equivalent thickness element. This method of analysis is found to be very versatile and may be used in both preliminary and final design stages. In order to illustrate the application of the proposed model, and to evaluate the contribution of the parameters involved, a case study is presented. Copyright © 2001 John Wiley & Sons, Ltd.
Three‐dimensional association of bending moment and shear force deformable panels
Authors: Mancini Eddie , Savassi Walter 
Published: September 2002

AbstractIn a previous paper, by using the continuous medium technique, the present authors showed that every plane panel, used to brace tall building structures acted upon by horizontal forces, is approximately equivalent to another panel composed of a shear wall joined to a two‐column frame by pinned horizontal bars. In this paper, the three‐dimensional association of such panels is considered. A simple example structure shows the advantage of the formulation, wherein very few parameters are needed to describe the whole structural behavior. Copyright © 2001 John Wiley & Sons, Ltd.