bluuebunny/crossref_metadata_2025 huggingface dataset:
Successful treatment with enoximone for severe poisoning with atenolol and verapamil: a case report
Authors: Sandroni C. , Cavallaro F. , Addario C. , Ferro G. , Gallizzi F. , Antonelli M.
Published: June 2004

Combined poisoning with calcium channel blockers (CCBs) and beta‐blockers is usually associated with severe hypotension and heart failure. Due to the block of the beta receptors, treatment with adrenergic agonists, even at high doses, can be insufficient, and beta‐independent inotropes, such as glucagon, may be required. Phosphodiesterase III (PDEIII) inhibitors represent a possible alternative to glucagon in these cases as they have an inotropic effect which is not mediated by a beta receptor.
Abolished circadian rhythm of melatonin secretion in sedated and artificially ventilated intensive care patients
Authors: Olofsson K. , Alling C. , Lundberg D. , Malmros C.
Published: June 2004

Background:  Sleep disturbance is common in intensive care patients. Aside from its unpleasantness, there is a correlation with intensive care unit (ICU) syndrome/delirium. Reasons for sleep deprivation appear to be multifactorial, including the underlying illness, an acute superimposed disturbance, medications, and the ICU environment itself. There are reasons to believe that alterations of the ‘biological clock’ might contribute. Melatonin secretion is one reflection of this internal sleep/wake mechanism. Melatonin levels are normally high during the night and low during daytime, being suppressed by bright light.

Methods:  Melatonin levels in blood and urine were studied over 3 consecutive days in eight critically ill patients during deep sedation and mechanical ventilation. Sedation was assessed with the sedation‐agitation (SAS) scale and bispectral index (BIS) monitor.

Results:  The circadian rhythm of melatonin release was abolished in all but one patient, who recovered much more quickly than the others. There was no correlation between melatonin levels and levels of sedation.

Conclusions:  This study indicates that dyssynchronization of the melatonin secretion rhythm is common in critically ill and mechanically ventilated patients. It could be hypothesized that an impairment of the melatonin rhythm may play a role in the development of sleep disturbances and delirium in intensive care patients, and that melatonin supply could reduce the incidence of these phenomena.
The role of smoking intentions in predicting future smoking among youth: findings from Monitoring the Future data
Authors: Wakefield Melanie , Kloska Deborah D. , O'Malley Patrick M. , Johnston Lloyd D. , Chaloupka Frank , Pierce John , Giovino Gary , Ruel Erin , Flay Brian R.
Published: June 2004

Aims  To demonstrate that intentions predict long‐term future levels of smoking, irrespective of level of past smoking experience. A growing body of research suggests that intentions about future smoking might play an important role in addition to the influence of past smoking experience on the likelihood of smoking in future.

Design  Using logistic regression analyses, we assessed the relationship between baseline smoking experience and a firm intention ‘not to be smoking cigarettes 5 years from now’ with four outcome measures of smoking at follow‐up: 30‐day smoking at a 3/4‐ and 5/6‐year follow‐up and current established smoking (self‐described regular smokers or former smokers who had smoked in the past 30 days) at a 3/4‐ and 5/6‐year follow‐up.

Participants  US nationally representative samples of 12th graders who responded to the Monitoring the Future (MTF) survey from the years 1976 to 1993, inclusive. For these panels, we linked stage of smoking and intentions at 12th grade to follow‐up measures of smoking collected at 3/4 years after baseline and 5/6 years after baseline.

Findings  Analysis of 3/4‐year follow‐up data (weighted n = 4544) and 5/6‐year follow‐up data (weighted n = 3885) for both definitions of smoking outcome indicated that there was a dose–response relationship between levels of baseline smoking experience and the likelihood of future smoking. In addition, independent of baseline smoking experience, there was a statistically significant protective effect for a firm intention not to smoke in five year's time on future smoking behavior.

Conclusions  The findings suggest that evaluative studies of tobacco control policies and programs might usefully employ smoking uptake categories that incorporate smoking intentions as early indicators of outcome.
Determination of the regularization level of truncated singular‐value decomposition inversion: The case of 1D inversion of MT data
Authors: Pedersen Laust B.
Published: June 2004

The total mean‐square error (MSE) of the estimated model, defined as the sum of the standard model variance and the bias variance, is used to define the truncation level of the singular‐value decomposition to give a reasonable balance between model resolution and model variance. This balance is determined largely by the data and no further assumptions are necessary except that the bias terms are estimated sufficiently well. This principle has been tested on the 1D magnetotelluric inverse problem with special emphasis on high‐frequency radio magnetotelluric (RMT) data. Simulations clearly demonstrate that the method provides a good balance between resolution and variance. Starting from a homogeneous half‐space, the best solution is sought for a fixed set of singular values. The model variance is estimated from the sum of the inverse eigenvalues squared, up to a certain threshold, and the bias variance is estimated from the model projections on the remaining eigenvectors. By varying the threshold, the minimum of the MSE is found for an increasing number of fixed singular values until the number of active singular values becomes greater than or equal to the estimated number. As a side‐effect, the depth of penetration of a given set of measurements can be estimated very efficiently by simply noting at which depth the final model deviates little from the starting homogeneous half‐space model. A suite of synthetic data is inverted and an example of inversion of one site is shown to illustrate how the truncation is carried out as the non‐linear inversion process proceeds. A field example with a profile across a plume of contaminated groundwater in the Netherlands shows good agreement with the electrical resistivity obtained in a nearby borehole.
Dispersion and radial depth of investigation of borehole modes
Authors: Sinha Bikash K. , Asvadurov Sergey
Published: June 2004

Sonic techniques in geophysical prospecting involve elastic wave velocity measurements that are performed by placing acoustic transmitters and receivers in a fluid‐filled borehole. The signals recorded at the receivers are processed to obtain compressional‐ and shear‐wave velocities in the surrounding formation. These velocities are generally used in seismic surveys for the time‐to‐depth conversion and other formation parameters, such as porosity and lithology. Depending upon the type of transmitter used (e.g. monopole or dipole) and as a result of eccentering, it is possible to excite axisymmetric(n= 0), flexural(n= 1)and quadrupole(n= 2)families of modes propagating along the borehole. We present a study of various propagating and leaky modes that includes their dispersion and attenuation characteristics caused by radiation into the surrounding formation. A knowledge of propagation characteristics of borehole modes helps in a proper selection of transmitter bandwidth for suppressing unwanted modes that create problems in the inversion for the compressional‐ and shear‐wave velocities from the dispersive arrivals. It also helps in the design of a transmitter for a preferential excitation of a given mode in order to reduce interference with drill‐collar or drilling noise for sonic measurements‐while‐drilling. Computational results for the axisymmetric family of modes in a fast formation with a shear‐wave velocity of 2032 m/s show the existence of Stoneley, pseudo‐Rayleigh and anharmonic cut‐off modes. In a slow formation with a shear‐wave velocity of 508 m/s, we find the existence of the Stoneley mode and the first leaky compressional mode which cuts in at approximately the same normalized frequencyωa/VS= 2.5(ais the borehole radius) as that of the fast formation. The corresponding modes among the flexural family include the lowest‐order flexural and anharmonic cut‐off modes. For both the fast and slow formations, the first anharmonic mode cuts in at a normalized frequencyωa/VS= 1.5approximately. Cut‐off frequencies of anharmonic modes are inversely proportional to the borehole radius in the absence of any tool. The borehole quadrupole mode can also be used for estimating formation shear slownesses. The radial depth of investigation with a quadrupole mode is marginally less than that of a flexural mode because of its higher frequency of excitation.
Joint cross‐well and single‐well seismic studies of CO2injection in an oil reservoir
Authors: Gritto R. , Daley T.M. , Myer L.R.
Published: June 2004

A series of time‐lapse seismic cross‐well and single‐well experiments were conducted in a diatomite reservoir to monitor the injection of CO2into a hydrofracture zone, based on P‐ and S‐wave data. A high‐frequency piezo‐electric P‐wave source and an orbital‐vibrator S‐wave source were used to generate waves that were recorded by hydrophones as well as 3‐component geophones. During the first phase the set of seismic experiments was conducted after the injection of water into the hydrofractured zone. The set of seismic experiments was repeated after a time period of seven months during which CO2was injected into the hydrofractured zone. The questions to be answered ranged from the detectability of the geological structure in the diatomic reservoir to the detectability of CO2within the hydrofracture. Furthermore, it was intended to determine which experiment (cross‐well or single‐well) is best suited to resolve these features.

During the pre‐injection experiment, the P‐wave velocities exhibited relatively low values between 1700 and 1900 m/s, which decreased to 1600–1800 m/s during the post‐injection phase (−5%). The analysis of the pre‐injection S‐wave data revealed slow S‐wave velocities between 600 and 800 m/s, while the post‐injection data revealed velocities between 500 and 700 m/s (−6%). These velocity estimates produced high Poisson's ratios between 0.36 and 0.46 for this highly porous (∼50%) material. Differencing post‐ and pre‐injection data revealed an increase in Poisson's ratio of up to 5%. Both velocity and Poisson's ratio estimates indicate the dissolution of CO2in the liquid phase of the reservoir accompanied by an increase in pore pressure.

The single‐well data supported the findings of the cross‐well experiments. P‐ and S‐wave velocities as well as Poisson's ratios were comparable to the estimates of the cross‐well data.

The cross‐well experiment did not detect the presence of the hydrofracture but appeared to be sensitive to overall changes in the reservoir and possibly the presence of a fault. In contrast, the single‐well reflection data revealed an arrival that could indicate the presence of the hydrofracture between the source and receiver wells, while it did not detect the presence of the fault, possibly due to out‐of‐plane reflections.
‘How did it know we weren't talking?’: An investigation into the impact of self‐assessments and feedback in a group activity
Authors: Ulicsak Mary H.
Published: June 2004

AbstractThe paper describes a model designed to support the development of children's group skills by explicitly scaffolding reflection on collaboration and providing feedback using the children's self‐assessment of these skills. The model incorporates existing training schemes, including procedural prompting, assigning roles, modelling exchanges, and giving feedback. This paper then reports a study that compared 9 and 10‐year‐old children who used a computer‐based implementation of this model (n=26) with children who did not use the system (n=25). The study found: a trend for improved recall of material studied, that the children believed the computer assessment of group skills used was correct, and finally, the time spent reflecting on their group behaviour increased when the children thought they were being observed by the system. The implications of these findings are discussed.
Splanchnic oxygen transport, hepatic function and gastrointestinal barrier after normothermic cardiopulmonary bypass
Authors: Braun J. P. , Schroeder T. , Buehner S. , Dohmen P. , Moshirzadeh M. , Grosse J. , Streit F. , Schlaefke A. , Armstrong V. W. , Oellerich M. , Lochs H. , Konertz W. , Kox W. J. , Spies C.
Published: June 2004

Background:  The effect of non‐pulsatile, normothermic cardiopulmonary‐bypass (CPB) on the splanchnic blood‐flow and oxygen‐transport, the hepatic function and the gastrointestinal barrier were observed in a prospective observational study in 31 adults undergoing cardiac valve replacement surgery.

Methods:  The splanchnic (i.e. hepatic) blood‐flow (HBF) was measured by the constant infusion of indocyanine‐green (ICG) using a hepatic‐venous catheter. Liver function was examined by calculation of lactate uptake, ICG extraction and the monoethylglycinexylidide (MEGX) test. A day before and after surgery the gastrioduodenal and intestinal permeability was measured by determination of sucrose and lactulose/mannitol excretion.

Results:  Splanchnic blood flow and oxygen delivery did not decrease during and after surgery while splanchnic oxygen consumption (P < 0.0125) and arterial lactate concentrations increased. The splanchnic lactate uptake paralleled the lactate concentration. After but not during CPB an increase of systemic oxygen consumption was observed. The MEGX test values decreased on the first day after surgery. The ICG extraction was attenuated during the operation. The gastroduodenal and the intestinal permeability increased significantly postoperatively (P < 0.002, respectively, P < 0.001). There was no correlation between these findings and the duration of CPB. There was a significant correlation of the intestinal permeability but not of the gastroduodenal permeability between the prior and after surgery values (P < 0.001).

Conclusion:  Increased oxygen consumption during CPB may indicate an inflammatory reaction due to the pump beginning in the splanchnic area or a redistribution of the splanchinc blood flow during the CPB. Normothermic CPB does not lead to a significant or prolonged reduction of liver function. Normothermic CPB causes an increase of gastrointestinal permeability. The intestinal barrier function prior to surgery was accountable for the degree of loss of intestinal barrier function following surgery.
Giving Away One's Poverty. on the Consumption of Scarce Resources within the Family
Authors: Kochuyt Thierry
Published: June 2004

This article draws on qualitative data from a Belgian poverty research. Intensive in-depth interviews questioned parents of deprived households about the way they deal with their limited means. To make ends meet, they are forced to restrain their personal needs and desires until they are adapted to the financial stringency of their condition. Further analysis of their situation is somehow confronted with a marked contrast between the parental austerity and the sometimes affluent way in which the wants of their young children are gratified. The poor household's consumption is indeed favouring the kids. Although there is not that much to share, the respondents prefer to neglect their own basic needs in order to satisfy their children's desires. This self-sacrifice is upholding one's honour as a parent and it develops at the same time a relationship with the children marked by affection, care and loyalty. By giving one can take up the parental role of a responsible actor who preserves his/her children from economic adversities. Consequently the gift bestows an identity upon the parents and helps to constitute a family bond marked by internal solidarity. This altruism clearly shows that consumption is not a simple deduction of the available income, nor is it a strictly utilitarian business. The means of consumption are also cultural means of communication, through which people assume roles and create social ties, resulting in a moral economy that tries to counter the misfortune of the outside world.
Personal Narratives, Relational Selves: Residential Histories in the Living and Telling
Authors: Mason Jennifer
Published: June 2004

This article is set in the context of debates about how far social identity and agency should be seen as individualised or relational concepts. It examines how people in a qualitative study in the North of England constructed personal narratives about their residential histories. These were fundamentally about identity and agency, because they centred upon ‘what mattered’ more widely to the narrator, and upon what had constrained or enabled action and change in their life. The narratives were characterised by contextuality, contingency and in particular by relationality. Four styles of relational narrative are explored: relational inclusion and co-presence, relational participation, relational constraint and conflict, and relational individualism. Overall, it is argued that both agency and identity need to be understood relationally, and that through their narratives people in the study were constructing relational selves. It is suggested that a misreading of personal narrative as an individualistic discursive form has fuelled the hold of the concept of individualism on popular and sociological imagination, in the face of increasingly compelling empirical evidence about the extent and nature of people's connectivity with others.
Markets, Contingency and Preferences: Contemporary Managers' Narrative Identities
Authors: Martin Bill , Wajcman Judy
Published: June 2004

We explore work identity amongst managers, a key group in the ‘new’ capitalism. Some existing accounts of such workplace identities emphasize new ‘cultures of control’, others focus on new requirements and possibilities of individual autonomy through reflective identity formation, while others identify a crisis in workplace identity formation. Focusing on these issues, we analyse the career narratives of 136 managers and show that our empirical data do not neatly fit any existing models. Managers' career stories were dominated by a ‘market’ narrative, in which they placed themselves as strategic actors making choices in a social world constituted by market-like interactions. We show that the market narrative frames how managers understand risks to their careers arising from the contingent actions of firms, and how it provides a space for managers to reflectively identify their preferences and pleasures. We consider the consequences of this analysis for contemporary understandings of work and identity.
Modelling Growth and Decline in Lung Function in Duchenne’s Muscular Dystrophy with an Augmented Linear Mixed Effects Model
Authors: Scott Marc A. , Norman Robert G. , Berger Kenneth I.
Published: June 2004

Longitudinal modelling of lung function in Duchenne’s muscular dystrophy is complicated by a mixture of both growth and decline in lung function within each subject, an unknown point of separation between these phases and significant heterogeneity between individual trajectories. Linear mixed effects models can be used, assuming a single changepoint for all cases; however, this assumption may be incorrect. The paper describes an extension of linear mixed effects modelling in which random changepoints are integrated into the model as parameters and estimated by using a stochastic EM algorithm. We find that use of this ‘mixture modelling’ approach improves the fit significantly.
A Class of Distribution-Free Control Charts
Authors: Chakraborti S. , van der Laan P. , van de Wiel M. A.
Published: June 2004

A class of Shewhart-type distribution-free control charts is considered. A key advantage of these charts is that the in-control run length distribution is the same for all continuous process distributions. Exact expressions for the run length distribution and the average run length (ARL) are derived and properties of the charts are studied via evaluations of the run length distribution probabilities and the ARL. Tables are provided for implementation for some typical ARL values and false alarm rates. The charts proposed are preferable from a robustness point of view, have attractive ARL properties and would be particularly useful in situations where one uses a classical Shewhart X-chart. A numerical illustration is given.
Optimal Predictive Sample Size for Case–Control Studies
Authors: De Santis Fulvio , Pacifico Marco Perone , Sambucini Valeria
Published: June 2004

The identification of factors that increase the chances of a certain disease is one of the classical and central issues in epidemiology. In this context, a typical measure of the association between a disease and risk factor is the odds ratio. We deal with design problems that arise for Bayesian inference on the odds ratio in the analysis of case–control studies. We consider sample size determination and allocation criteria for both interval estimation and hypothesis testing. These criteria are then employed to determine the sample size and proportions of units to be assigned to cases and controls for planning a study on the association between the incidence of a non-Hodgkin’s lymphoma and exposition to pesticides by eliciting prior information from a previous study.
Clinicopathological spectrum of mycosis fungoides
Authors: Kazakov DV , Burg G , Kempf W
Published: June 2004

Cutaneous lymphomas represent a heterogeneous group of T‐, NK‐ and B‐cell neoplasms, with mycosis fungoides (MF) being the most common subtype. MF has a plethora of clinicopathological manifestations. Many variants of this lymphoma differ substantially from the ‘classical’ Alibert–Bazin disease and are therefore sometimes referred to as ‘atypical’ forms of the disease. This review addresses the whole clinicopathological spectrum of mycosis fungoides with respect to epidemiology, clinical, histopathological, immunophenotypic and genotypic features and the clinical course and prognosis of its variants: classical, erythrodermic, follicular, syringotropic, bullous/vesicular, granulomatous, poikilodermic, hypo‐ and hyperpigmented, unilesional, palmoplantar, hyperkeratotic/verrucous, vegetating/papillomatous, ichthyosiform, pigmented purpura‐like, pustular and mucosal involvement in MF.
Sutures and Burrow's triangles placed in the red vermilion in the surgery of upper lip defects
Authors: Ascari‐Raccagni A , Baldari U
Published: June 2004

Background  In upper lip defects both the design of the flap and the position of the Burrow's triangles may be reversed so as to conceal the scars among skin wrinkles, folds and the mucosal lip to maximize the aesthetic outcome.

Objective  To report two cases of upper lip defects in which both scars and Burrow's triangles were concealed in the natural folds and the vermilion.

Methods  Both surgeries were performed under local anaesthesia.

Result  In both patients the scars were successfully concealed and the results aesthetically acceptable.

Conclusion  The technique described can be used to conceal scars in cases of upper lip defects with aesthetically acceptable results.
Bullous systemic lupus erythematosus with antiphospholipid syndrome
Authors: Kacalak‐Rzepka A , Zaluga E , Maleszka R , Królicki A , Klimowicz A
Published: June 2004

We report the case of a 44‐year‐old male with a 10‐year history of manifestations of the rare form of bullous systemic lupus erythematosus (SLE) with coexisting antiphospholipid syndrome (APS) that remained undiagnosed until thrombotic‐embolic episodes appeared and high titres of anticardiolipin (ACL) antibodies were detected. The patient fulfilled the criteria for SLE and the atypical cutaneous manifestations together with histopathological changes and a favourable response to sulphones were the grounds for the diagnosis of the bullous variety of SLE. Treatment with prednisolone, acenocoumarol and dapsone resulted in marked clinical improvement, reduction in antinuclear antibodies (ANAs) and normalization of ACL antibody titres.
Brain electrocortical activity during and after exercise: A quantitative synthesis
Authors: Crabbe James B. , Dishman Rod K.
Published: June 2004

Investigators of brain electrocortical responses to exercise have interpreted increased activity, or frontal hemispheric asymmetry, in the alpha frequency band as indicative of relaxation or a change in affect. However, few studies compared alpha activity with other frequencies and within or across hemispheres. To clarify the cumulative evidence in this area, we provide a quantitative review of the effects of exercise on brain electrocortical activity according to frequency bands and recording sites. Fifty‐eight effects from 18 studies and 282 participants were retrieved. The mean effect size was moderately large (0.54 SD, 95% CI: 0.43 to 0.65) but heterogeneous. Compared to before exercise, alpha activity was greater immediately after and during exercise when expressed as absolute power but not as relative to power in other frequency bands; delta, theta, and beta activity also increased (0.38 to 0.75 SD). Effects did not differ significantly by recording sites. The cumulative evidence does not indicate that change in brain electrocortical activity after exercise is specific to alpha activity or hemispheric site.
Life‐span changes in P3a
Authors: Fjell Anders M. , Walhovd Kristine B.
Published: June 2004

The relationship of visual P3a to age was investigated in a life‐span sample. The aims of the study were (1) to assess to what extent P3a, relative to P3b, decreases with increasing age; (2) To assess at which recording sites the relationship between P3a and age is strongest; (3) to investigate whether the relationship between P3a and age is best described as linear or nonlinear. One hundred and three well‐functioning adults, 20–92 years old, were given a health interview, a battery of neuropsychological tests, and performed a visual three‐stimuli oddball ERP task yielding both a P3a and a P3b. P3a and age was moderately correlated, with coefficients reaching .53 (Cz) and −.52 (Pz) for latency and amplitude, respectively. P3b was to a much lesser extent related to age. Generally, the age–P3a relationship was strongest at midline and central electrodes. Finally, the relationship between age and P3a was best described as linear. P3a seems selectively more impaired with age than P3b, but this impairment seems less pronounced at Fz than at Cz and Pz. There is a need for complex theoretical integration of these and previous findings.
The electrophysiological correlates sustaining the retrieval of face–name associations: An ERP study
Authors: Joassin F. , Campanella S. , Debatisse D. , Guerit J.M. , Bruyer R. , Crommelinck M.
Published: June 2004

An ERP study on 9 healthy participants was carried out to temporally constrain the neural network proposed by Campanella et al. (2001) in a PET study investigating the cerebral areas involved in the retrieval of face–name associations. Three learning sessions served to familiarize the participants with 24 face–name associations grouped in 12 male/female couples. During EEG recording, participants were confronted with four experimental conditions, requiring the retrieval of previously learned couples on the basis of the presentation of name–name (NN), face–face (FF), name–face (NF), or face–name (FN) pairs of stimuli. The main analysis of this experiment consisted in the subtraction of the nonmixed conditions (NN and FF) from the mixed conditions (NF and FN). It revealed two main ERP components: a negative wave peaking at left parieto‐occipital sites around 285 ms and its positive counterpart recorded at left centro‐frontal electrodes around 300 ms. Moreover, a dipole modeling using three dipoles whose localization corresponded to the three cerebral areas observed in the PET study (left inferior frontal gyrus, left medial frontal gyrus, left inferior parietal lobe) explained more than 90% of the variance of the results. The complementarity between anatomical and neurophysiological techniques allowed us to discuss the temporal course of these cerebral activities and to propose an interactive and original anatomo‐temporal model of the retrieval of face–name associations.
Automatic time perception in the human brain for intervals ranging from milliseconds to seconds
Authors: Näätänen Risto , Syssoeva Olga , Takegata Rika
Published: June 2004

Time perception in everyday life deals with various intervals. Here we investigated whether an automatic duration‐discrimination mechanism in audition operates even for intervals of an order of seconds, by using the mismatch negativity (MMN), an index of automatic change detection in audition. In Experiment 1, occasional decrements of the duration of a repetitive “standard” tone elicited an MMN in subjects ignoring auditory stimulation, even with the standard‐stimulus durations over a second. Nevertheless, the MMN amplitude was significantly diminished with standard‐stimulus durations of 800 ms and above, despite the fact that a constant deviant versus standard duration ratio was used. Complementary experiments varying the interstimulus interval (Experiment 2) and the magnitude of duration change (Experiment 3) yielded corroborating results. The present results suggest that automatic duration discrimination in audition operates even for durations of the order of seconds; yet its optimum time scale might be of the order of milliseconds.
Spatiotemporal analysis of event‐related potentials to upright, inverted, and contrast‐reversed faces: Effects on encoding and recognition
Authors: Itier Roxane J. , Taylor Margot J. , Lobaugh Nancy J.
Published: June 2004

In an n‐back face recognition task where subjects responded to repeated stimuli, ERPs were recorded to upright, inverted, and contrast‐reversed faces. The effects of inversion and contrast reversal on face encoding and recognition were investigated using the multivariate spatiotemporal partial least squares (PLS) analysis. The configural manipulations affected early processing (100–200 ms) at posterior sites: Inversion effects were parietal and lateral, whereas contrast‐reversal effects were more occipital and medial, suggesting different underlying generators. A later reactivation of face processing areas was unique to inverted faces, likely due to processing difficulties. PLS also indicated that the “old–new” repetition effect was maximal for upright faces and likely involved frontotemporal areas. Marked processing differences between inverted and contrast‐reversed faces were seen, but these effects were similar at encoding and recognition.
Aerobic exercise training and cardiovascular reactivity to psychological stress in sedentary young normotensive men and women
Authors: Spalding Thomas W. , Lyon Lewis A. , Steel Donald H. , Hatfield Bradley D.
Published: June 2004

Forty‐five (22 women) sedentary young (18–30 years old) nonsmoking normotensive volunteers engaged in either 6 weeks of aerobic training (AT), weight training (WT), or a no‐treatment (NT) condition to determine whether AT lowers systolic (SBP) and diastolic (DBP) blood pressure, heart rate (HR), and rate‐pressure product (RPP) during rest, psychological stress, and recovery periods. Estimated VO2max increased for the AT (32.1±1.1 to 38.4±1.0 ml·kg−1·min−1). A smaller increase for the WT (30.5±1.1 to 33.8±1.0) was likely due to increased leg strength, and VO2max did not change for the NT (32.5±1.1 to 32.9±1.0). Heart rate and RPP levels were lower during psychological stress and recovery after training for AT relative to the WT and NT. Overall SBP was also lower in the AT relative to the NT but not the WT. In conclusion, aerobic training lowered cardiovascular activity levels during psychological stress and recovery in healthy young adults, implying a protective role against age‐related increases in coronary heart disease for individuals who adopt aerobic exercise early in life and maintain the behavior across the life span.
The psychophysiology of the maternal–fetal relationship
Authors: Dipietro Janet A. , Irizarry Rafael A. , Costigan Kathleen A. , Gurewitsch Edith D.
Published: June 2004

The enigmatic quality of the maternal–fetal relationship has been extolled throughout history with little empirical support. We apply time series analysis to data for 137 maternal–fetal pairs collected at 20, 24, 28, 32, 36, and 38 weeks gestation. Maternal heart rate and skin conductance data were digitized in tandem with fetal heart rate and motor activity. No temporal relations between fetal heart rate and either maternal variable were found, although averaged maternal and fetal heart rates were correlated from 32 weeks. Consistent temporal associations between fetal movement and maternal heart rate and skin conductance were detected. Fetal movement stimulated rises in each parameter, peaking at 2 and 3 s, respectively. Associations did not change over gestation, were unaffected by a maternal stressor, and showed within‐pair stability. The bidirectional nature of the maternal–fetal relationship is considered.
Neurophysiological correlates of word and pseudo‐word processing in well‐recovered aphasics and patients with right‐hemispheric stroke
Authors: Pulvermüller Friedemann , Mohr Bettina , Lutzenberger Werner
Published: June 2004

Neurophysiological correlates of language recovery after stroke were investigated. Neurological patients with single focal lesions in their left or right hemisphere and healthy control subjects made lexical decisions on written words and pseudo‐words while EEG responses were recorded. At the time of testing, patients did not show clinically apparent language dysfunction, although those with left‐hemisphere lesions had suffered from aphasia in the first months after their stroke. A P3‐like positive deflection of the event‐related potential (ERP) was reduced in the patients relative to healthy controls, this reduction being most pronounced over the hemisphere affected by stroke. Consistent with earlier research, healthy control subjects showed more positive ERPs to words than to pseudo‐words. This pattern was reversed in both patient groups, where words elicited more negative‐going ERPs than pseudo‐words already 160–320 ms after stimulus onset. Because ERPs showed between‐group differences only for words, these word‐specific neurophysiological signatures altered in stroke patients with well‐recovered language functions may be a correlate of cortical lesions or an index of reorganization of language after stroke.
Stability, consistency, and heritability of electrodermal response lability in middle‐aged male twins
Authors: Crider Andrew , Kremen William S. , Xian Hong , Jacobson Kristen C. , Waterman Brian , Eisen Seth A. , Tsuang Ming T. , Lyons Michael J.
Published: June 2004

We examined individual differences in nonspecific electrodermal response (EDR) lability in terms of retest stability, cross‐situational consistency, and heritability in a sample of 345 adult monozygotic and dizygotic twin pairs. We also examined the phenotypic and genetic relationships between EDR lability and speed of habituation of the specific EDR to a nonsignal stimulus. Individual variation in EDR lability showed substantial retest stability and cross‐situational consistency and also predicted resistance to specific EDR habituation. Structural equation modeling showed that the covariation among EDR lability measures and resistance to specific EDR habituation operated through a single latent phenotype, which was influenced in approximately equal measure by genetic and unique environmental factors. We discuss these findings in terms of an information processing account of individual differences in phasic EDR activation.
Mental stress‐induced hemoconcentration: Sex differences and mechanisms
Authors: Veldhuijzen Van Zanten Jet J. C. S. , Ring Christopher , Burns Victoria E. , Edwards Kate M. , Drayson Mark , Carroll Douglas
Published: June 2004

Given the possible role of hemoconcentration in myocardial infarction and apparent sex differences in susceptibility, three studies examined sex differences in mental stress‐induced hemoconcentration, and explored possible underlying mechanisms. Blood pressure, heart rate, and hematocrit were monitored at rest and in response to a mental stress task that was contrived to be increasingly provocative across the three studies. This was confirmed by self‐report, performance, and cardiovascular reactivity data. The most convincing evidence for hemoconcentration effects and sex differences in hemoconcentration emerged from exposure to the more provocative of the stress tasks, with men also showing greater hemoconcentration than women. Blood pressure reactivity was a strong and consistent predictor of stress‐induced hemoconcentration. These findings may help to explain sex differences in susceptibility to myocardial infarction.
Comparison of sensory gating to mismatch negativity and self‐reported perceptual phenomena in healthy adults
Authors: Kisley Michael A. , Noecker Tara L. , Guinther Paul M.
Published: June 2004

To better understand the possible functional significance of electrophysiological sensory gating measures, response suppression of midlatency auditory event related potential (ERP) components was compared to the mismatch negativity (MMN) and to self‐rated indices of stimulus filtering and passive attention‐switching phenomena in an age‐restricted sample of healthy adults. P1 sensory gating, measured during a paired‐click paradigm, was correlated with MMN amplitude, measured during an acoustic oddball paradigm (intensity deviation). Also, individuals that exhibited less robust P1 suppression endorsed higher rates of “perceptual modulation” difficulties, whereas component N1 suppression was more closely related to “over‐inclusion” of irrelevant sounds into the focus of attention. These findings suggest that the ERP components investigated are not redundant, but correspond to distinct—possibly related—pre‐attentive processing systems.
Latent inhibition mediates N1 attenuation to repeating sounds
Authors: Sable Jeffrey J. , Low Kathy A. , Maclin Edward L. , Fabiani Monica , Gratton Gabriele
Published: June 2004

Sound repetition typically reduces auditory N1 amplitudes, more so at higher rates. This has been attributed to refractoriness of N1 generators. However, evidence that N1 attenuation is delayed 300–400 ms after the first occurrence of a repeated sound suggests an alternative process, such as inhibition, that requires 300–400 ms to become fully operational. We examined the N1 to trains of fixed‐interval (100, 200, 300, 400 ms) tones for evidence of effects predicted by models of refractoriness and of latent inhibition. Regardless of interval, latency of the eliciting tone from train onset determined N1 amplitudes during the first 400 ms of the train, which decreased in this window. The results show that N1 attenuation cannot be due simply to refractoriness, which would elicit the smallest N1 to the second tone. An inhibitory neural circuit can account for these and previous results, and may be important to auditory perceptual processing.
The effect of the menstrual cycle on electrophysiological and behavioral measures of memory and mood
Authors: O'Reilly Michelle A. , Cunningham Conal J. , Lawlor Brian A. , Walsh Cathal D. , Rowan Michael J.
Published: June 2004

Event‐related potentials (ERPs) were compared between the menses and ovulatory phase of the menstrual cycle in response to visually presented words, some of which were repeated as part of direct and indirect memory tasks. Twelve spontaneously cycling women were tested during the menses and ovulatory phases. For the direct task, participants had to discriminate between new words and those repeated after a mean of six trials. In the indirect task, subjects were required to discriminate between target and nontarget words. Some of the nontarget words were repeated after a mean of six trials. The ERP repetition effect mean amplitude was significantly greater in response to repeated words at both cycle phases but did not differ across the cycle. P300 amplitude was significantly greater during menses than the ovulatory phase. We conclude that context updating mechanisms as indexed by the P300 are sensitive to cyclic hormonal fluctuations.
Heart rate and skin conductance analysis of antecendents and consequences of decision making
Authors: Crone Eveline A. , Somsen Riek J. M. , Beek Bert Van , Van Der Molen Maurits W.
Published: June 2004

The current study examined the pattern of heart rate and skin conductance changes preceding risky choices and following outcome for bad, moderate, and good performers on an analogue of the Iowa gambling task (Bechara, Damasio, Damasio, & Anderson, 1994). The task required a choice between four options; two options were followed by a high reward and, unpredictably, an even higher loss (disadvantageous options) and two other options were followed by a small reward but the unpredictable loss was also small (advantageous options). Anticipatory heart rate slowing and skin conductance level were higher preceding disadvantageous relative to advantageous options, but only for good performers. In contrast, heart rate slowed and skin conductance level increased following loss relative to reward outcomes, and these changes were similar for all performance groups. These findings were interpreted to suggest that decision‐making impairments in bad performers arise from a weak somatic response generated by secondary inducers (i.e., somatic markers), rather than a weak somatic response generated by primary inducers of reward and punishment.
Focal epithelial hyperplasia (Heck's disease): report of two cases with PCR detection of human papillomavirus DNA
Authors: Jayasooriya PR , Abeyratne S , Ranasinghe AW , Tilakaratne WM
Published: June 2004

Focal epithelial hyperplasia (FEH) (Heck's disease) is essentially a benign oral infection produced by the human papillomavirus (HPV). Although this condition is known to exist in numerous populations and ethnic groups, it is relatively rare in South‐East Asia. The following report is based on two cases of adult FEH with histopathological features in favour of the disease. In addition, polymerase chain reaction was performed to detect the presence of HPV DNA in the lesions in order to confirm the histopathological diagnosis.
Plasticity of the β cell insulin secretory competence: preparing the pancreatic β cell for the next meal
Authors: Hinke Simon A. , Hellemans Karine , Schuit Frans C.
Published: June 2004

It is well established that the acute rise in plasma glucose and in the incretin hormones glucose‐dependent insulinotropic peptide (GIP) and glucagon‐like peptide‐1 (7–36) amide (GLP‐1), as occurs during a meal, is of pivotal importance in regulating the minute‐to‐minute output of insulin from pancreatic β cells. In addition to this well studied acute effect, both glucose and incretin hormones have been recently observed to determine the future secretory responsiveness of the cells. Such plasticity of the insulin secretory competence would imply that glucose and incretins not only act during the present meal, but also help to prepare the β cells to function during the subsequent meal. Evidence supporting this hypothesis is growing as a result of physiological studies of cultured β cells (either primary cells or β cell lines), as well as from an increasing number of large‐scale gene expression studies, exploring transcriptional and post‐transcriptional events in genes regulated by glucose and incretins. On the basis of this hypothesis, one can speculate that genetic or environmental disturbances of plasticity of the insulin secretory competence is one aspect of β cell dysfunction that can contribute to the aetiology of type 2 diabetes.
An Optimized CD4 T-Cell Response Can Control Productive and Latent Gammaherpesvirus Infection
Authors: Sparks-Thissen Rebecca L. , Braaten Douglas C. , Kreher Scott , Speck Samuel H. , Virgin Herbert W.
Published: June 2004

CD4 T cells are important for control of infection with murine gammaherpesvirus 68 (γHV68), but it is not known whether CD4 T cells function via provision of help to other lymphocyte subsets, such as B cells and CD8 T cells, or have an independent antiviral function. Moreover, under conditions of natural infection, the CD4 T-cell response is not sufficient to eliminate infection. To determine the functional capacities of CD4 T cells under optimal or near-optimal conditions and to determine whether CD4 T cells can control γHV68 infection in the absence of CD8 T cells or B cells, we studied the effect of ovalbumin (OVA)-specific CD4 T cells on infection with a recombinant γHV68 that expresses OVA. OVA-specific CD4 T cells limited acute γHV68 replication and prolonged the life of infected T-cell receptor-transgenic RAG (DO.11.10/RAG) mice, demonstrating CD4 T-cell antiviral activity, independent of CD8 T cells and B cells. Despite CD4 T-cell-mediated control of acute infection, latent infection was established in DO.11.10/RAG mice. However, OVA-specific CD4 T cells reduced the frequency of latently infected cells both early (16 days postinfection) and late (42 days postinfection) after infection of mice containing CD8 T cells and B cells (DO.11.10 mice). These results show that OVA-specific CD4 T cells have B-cell and CD8 T-cell-independent antiviral functions in the control of acute infection and can, in the absence of preexisting CD8 T-cell or B-cell immunity, inhibit the establishment of gammaherpesvirus latency.
Regulation of Hepatitis B Virus Core Promoter by Transcription Factors HNF1 and HNF4 and the Viral X Protein
Authors: Zheng Yanyan , Li Jie , Ou Jing-hsiung
Published: June 2004

Hepatitis B virus (HBV) core promoter contains a binding site for nuclear receptors. A natural double mutation in this binding site, which changes nucleotide (nt) 1765 from A to T and nt 1767 from G to A, selectively abolishes the binding of several nuclear receptors without affecting that of HNF4. This double mutation also creates a binding site for the transcription factor HNF1 and changes two amino acids in the overlapping X protein sequence. In this study, we have examined the roles of HNF1, HNF4, and the X protein in the regulation of the core promoter activities in Huh7 hepatoma cells. Our results indicate that HNF4 could stimulate the expression of the precore RNA and the core RNA from the core promoter of both the wild-type (WT) HBV and the double mutant, although its effect on the former was more prominent. In contrast, HNF1, which did not affect the WT core promoter, suppressed the precore RNA expression of the double mutant. Further analysis using HBV genomic constructs, with and without the ability to express the X protein, indicates that the X protein did not affect the HNF4 activity on the core promoter and affected the HNF1 activity on the core promoter of only the double mutant. Thus, our results indicate that the phenotypic differences of HBV WT and double-mutant core promoters are at least partially due to the differential activities of HNF1, HNF4, and the X protein on these two promoters.