bluuebunny/crossref_metadata_2025 huggingface dataset:
Tuberous Sclerosis and Multiple Tubers: Localizing the Epileptogenic Zone
Authors: Weiner Howard L.
Published: July 2004

Summary:  Tuberous sclerosis complex (TSC) is associated with medically refractory seizures and developmental delay in children. These epilepsies are often resistant to antiepileptic drugs (AEDs), may be quite severe, and usually have a negative impact on the child's neurological and cognitive development. It is believed that functional outcome is improved if seizures can be controlled at an early age. The surgical treatment of intractable epilepsy in children and adults with TSC has gained significant interest in recent years. Previously published studies have shown a potential benefit from resection of single tubers, with most of the results noted in relatively older children. All of these reports support the idea that if a single primary epileptogenic tuber/region can be identified, then a surgical approach is appropriate. However, most children with TSC have multiple potentially epileptogenic tubers, rendering localization challenging, and they are therefore rejected as possible surgical candidates. We have utilized a novel surgical approach using invasive intracranial monitoring, which is typically multistaged and bilateral. Here we present an illustrative case of a young boy with TSC and medically refractory epilepsy who underwent a staged surgical approach. This multistage surgical approach has been useful in identifying both primary and secondary epileptogenic zones in TSC patients with multiple tubers. Multiple or bilateral seizure foci are not necessarily a contraindication to surgery in selected TSC patients. Long‐term follow‐up will determine whether this approach has durable effects. We await better methods for identifying the epileptogenic zone, both noninvasive and invasive.
Laminar Analysis of Human Neocortical Interictal Spike Generation and Propagation: Current Source Density and Multiunit Analysis In Vivo
Authors: Ulbert Istvan , Heit Gary , Madsen Joseph , Karmos George , Halgren Eric
Published: July 2004

Summary:  Multicontact microelectrodes were chronically implanted in epilepsy patients undergoing subdural grid implantation for seizure localization. Current source density and multiple unit activity of interictal spikes (IISs) were sampled every ∼150 μm in a line traversing all layers of a cortical column. Our data suggest that interictal epileptiform events in humans are initiated by large postsynaptic depolarizations, consistent with the hypothesis that human IISs correspond to animal paroxysmal depolarization shifts. Furthermore, the cortical layer where the initial depolarization occurs may differ according to whether the IIS is locally generated or propagated from a distant location, and among the propagated IISs, whether the IIS is in the direct path of propagation or on the periphery of that path.
Magnetoencephalography in Epilepsy
Authors: Knowlton Robert C. , Shih Jerry
Published: July 2004

Summary:  Magnetoencephalography (MEG)—also known as magnetic source imaging when combined with magnetic resonance imaging—has developed to the point that it has now entered routine clinical application. Epilepsy MEG studies show that it can accurately localize spike sources—both ictal and interictal—as compared to both direct (intracranial EEG) and indirect (imaging abnormalities) measures. Challenges remain with difficulties in detecting complex or deep sources when recording spontaneous cerebral activity. Magnetoencephalography not only provides a novel tool to localize and characterize epileptiform disturbances, it also has an important role in determining the significance of abnormalities seen on both structural and functional imaging. Combined with mapping of normal or eloquent brain function, MEG should ultimately play a major role in the totally noninvasive epilepsy surgery evaluation.
Status Epilepticus and Periictal Imaging
Authors: Cole Andrew J.
Published: July 2004

Summary:  Peri‐ and postictal changes on both anatomic and functional imaging examinations have been recognized for many years. With the wide availability of magnetic resonance imaging and positron emission tomography, a growing range of recognized acute imaging findings have been described. Periictal and postictal findings can be classified as either local or remote, with respect to the site of maximal ictal EEG abnormality. Although many of the findings described are reversible, the factors that determine whether findings will resolve are incompletely understood. This article considers the range of findings that have been described, places them into the context of known or hypothesized pathophysiologic mechanisms, and considers their clinical significance. A framework is proposed for considering the relation between ictal duration and severity, the characteristics of imaging abnormalities, and the mechanism of their underlying pathophysiology.
Diagnosis of Infantile Spasms, Lennox‐Gastaut Syndrome, and Progressive Myoclonic Epilepsy
Authors: Shields W. Donald
Published: July 2004

Summary:  The epilepsies of childhood are distinguished by an interesting dichotomy between the benign and catastrophic disorders. Approximately 50% of children outgrow childhood epilepsy as they mature; although the disorder is disruptive for children and families alike, it is not considered a medical disaster. The catastrophic epilepsies of childhood, in contrast, are associated with significant morbidity and mortality. Infantile spasms, Lennox‐Gastaut syndrome, and the progressive myoclonic epilepsies are correlated with significant disability and a multiplicity of underlying etiologies. Accurate diagnosis of both the syndrome and the etiology is very important for treatment purposes, as well as for family education, since many of the disorders have a significant genetic component.
Following Catastrophic Epilepsy Patients from Childhood to Adulthood
Authors: Glauser Tracy A.
Published: July 2004

Summary:  As patients with catastrophic epilepsies move from childhood to adulthood, evolving and innovative therapeutic regimens are often required. However, the goal of providing the best quality of life while minimizing both seizures and side effects remains the same. Clinicians can develop appropriate care plans by being aware of patients' changing needs. Clinical symptoms of the catastrophic epilepsies may change over time; by understanding the natural history of a patient's condition, clinicians can help ease the transition from childhood to adulthood. Additionally, as children with catastrophic epilepsies become adults, medical issues (e.g., medication side effects, tolerance, and dependence) and nonmedical issues (e.g., guardian/caretaker issue, group home applications, and respite care options) must be considered when developing strategies for patient care. Regular assessment of patients, the development of emergency plans, and maintenance of consistency in the delivery of care are also important issues to consider. Finally, a multidisciplinary care plan that incorporates resources from health‐care practitioners, social service professionals, and community agencies can be valuable in optimizing treatment for patients with catastrophic epilepsies.
Personal Characteristics, Unemployment, and Anxiety among Highly Educated Immigrants
Authors: Lev‐Wiesel Rachel , Kaufman Roni
Published: July 2004

This exploratory study examines the relationship between personal resources (sense of potency, marital quality, social support from family and friends), the duration of unemployment, and the level of state anxiety experienced by highly educated, unemployed, middle‐aged immigrants. Studying the anxiety levels among populations at‐risk such as unemployed immigrants is particularly important in the context of situations of military conflict. In such situations, when formal support systems are in the process of erosion, the unemployed must increasingly rely on social and familial support. The following measures were examined in an anonymous, self‐report questionnaire: potency (defined as a person's enduring confidence in his/her own capacities and confidence in, and commitment to, his/her social environment which is perceived as being characterized by a basically meaningful order and just distribution of rewards), social support from friends and family, marital quality, and state anxiety. Results indicate that personal resources – particularly potency and social support from family – predicted the level of state anxiety among immigrants. Duration of unemployment was also positively correlated with state anxiety. A major recommendation that emerges is the need to foster the development of social support groups consisting of both veterans and new immigrants in order to broaden the social ties of the immigrants. This may assist newcomers not only in finding jobs, but also in coping with political and economic uncertainties in a new cultural context.
Irregular and Illegal Migration through Ukraine
Authors: Uehling Greta
Published: July 2004

With the expansion of Europe's borders, Ukraine has entered the spotlight of attention as a source and transit country for irregular migrants. Irregular migration has risen on the international security and political agendas because it is perceived as a threat to security, and has been linked to problems such as crime and drugs. In the debate about how to manage this migration, the voices of the migrants themselves are often lost.

Drawing on a review of the literature and migrants' testimonies, this paper argues that assumptions about irregular migrants in policy and position papers can be revised in light of migrants' experiences. For example, whereas officials and workers in non‐governmental organizations often picture irregular migration in terms of an inexorable striving, what migrants emphasize most is the undesirable nature of their movement. And, whereas many sources view irregular migration as symptomatic of globalization and the transnational “flows” of people, capital, and ideas, asylum seekers who become irregular in the absence of a strong asylum system in Ukraine describe highly constrained lives that include detention and isolation.

Before more efforts are directed toward combating irregular migration, migrants' descriptions of a traumatic and transformative experience of being “turned into illegals”, and “broken” can be taken into account. While there is a tendency to view the migrants as the problem, this paper suggests it is international migration regimes and not migrants that need amendment and improvement.
War and Forced Migration in the Indian Ocean: The US Military Base at Diego Garcia
Authors: Vine David
Published: July 2004

Between 1967 and 1973, the indigenous people of the Indian Ocean's Chagos Archipelago were forcibly displaced from their homelands so the US Government could construct a strategic military base on the island of Diego Garcia. The people of Diego Garcia and the rest of the Chagos Archipelago now live in poverty in the island nations of Mauritius and Seychelles, nearly 2,000 kilometres from their homes. Analysing formerly classified government documents, this paper demonstrates how between the end of World War II and the final removals in 1973, the US Government planned, ordered, financed, helped orchestrate, and participated in the expulsion of the exiled people, known as Chagossians or Ilois. While some have detailed the role the British Government played in the removals, this paper clarifies how the US Government bears primary responsibility for the expulsion. Ultimately the creation of the base at Diego Garcia and the expulsion of the Chagossians reveal much about how the United States has exercised its political, economic, and military will on the world since World War II. The paper explains the significance of Diego Garcia and the expulsion of the Chagossians to post‐war US foreign relations, incorporating comparative analyses of other forced migrations caused by the construction of US military facilities, including those in the Marshall Islands; Thule, Greenland; Okinawa, Japan; and Vieques, Puerto Rico.
Structuring health needs assessments: the medicalisation of health visiting
Authors: Cowley Sarah , Mitcheson Jan , Houston Anna M.
Published: July 2004

Abstract  This paper draws on Foucault to understand the changing discourse and impact of structured ‘health needs assessments’ on health visiting practice. Literature about this activity makes little mention of the long‐standing social purposes of health visiting, which include surveillance of vulnerable and invisible populations, providing them, where needed, with help and support to access protective and supportive services. Instead, the discourse has been concerned primarily with an epidemiological focus and public health, which is associated with risk factors and assessments.

The use of pre‐defined needs assessment schedules suggests that health visiting activity can be sanctioned and clients’ needs serviced only if they reach the threshold of pre‐determined, epidemiologically‐defined risk. Their effect on practice is examined through a conversation analysis of ten health visitor/client interactions using two different structured needs assessment tools. The study indicates that the health visitors, like their clients, were controlled by institutional expectations of their role; analysis of their conversations shows how they achieved the requirements of the organisational agenda. Structuring client needs and health visiting practice through the use of formal needs assessment tools emphasises the epidemiological focus of the health service above the need to arrange support for vulnerable individuals. In this respect, it serves as a marker in the continued medicalisation of health visiting.
Accounting for Irish Catholic ill health in Scotland: a qualitative exploration of some links between ‘religion’, class and health
Authors: Walls Patricia , Williams Rory
Published: July 2004

Abstract This paper considers the ways in which accounts from Glasgow Catholics diverge from those of Protestants and explores the reasons why people leave jobs, including health grounds. Accounts reveal experiences distinctive to Catholics, of health‐threatening stress, obstacles to career progression within (mainly) private‐sector organisations, and interactional difficulties which create particular problems for (mainly) middle class men. This narrows the employment options for upwardly mobile Catholics, who may then resort to self‐employment or other similarly stressful options. The paper considers whether the competence of Catholics or Catholic cultural factors are implicated in thwarting social mobility among Catholics or, alternatively, whether institutional sectarianism is involved. We conclude that, of these options, theories of institutional sectarianism provide the hypothesis which currently best fits these data. In Glasgow, people of indigenous Irish descent are recognisable from their names and Catholic background and are identified as Catholic by others. Overt historical exclusion of Catholics from middle class employment options now seems to take unrecognised forms in routine assumptions and practices which restrict Catholic employment opportunities. It is argued that younger Catholics use education to overcome the obstacles to mobility faced by older people and circumvent exclusions by recourse to middle class public‐sector employment. This paper aims to link historical, structural and sectarian patterns of employment experience to accounts of health and work, and in so doing to contribute to an explanation for the relatively poor health of Catholic Glaswegians with Irish roots.
A disputed occupational boundary: operating theatre nurses and Operating Department Practitioners
Authors: Timmons Stephen , Tanner Judith
Published: July 2004

Abstract  Traditionally, surgeons (and to a lesser extent anaesthetists) have been assisted primarily by nurses. This role has been threatened in recent years, in the UK NHS (and elsewhere), by a relatively new profession, that of the Operating Department Practitioner (ODP). The ODP profession is still in the process of establishing itself as a ‘full’ profession within UK health care. While occupational boundary disputes between professions are common in health care, it is unusual for them to become as overt as the dispute we will analyse in this paper. Drawing on fieldwork observations and interviews conducted in operating theatres, as well as documentary sources, we will show how this dispute arose, how it is manifested at both the micro and the macro level, and how both groups involved justify their positions, drawing on surprisingly similar rhetorical strategies. A further unusual feature of this dispute is the fact that, unlike many attempts by managers to substitute one type of labour for another, issues of cost are relatively unimportant, as both theatre nurses and ODPs earn similar salaries.
Passing Between the Clashing Rocks: The Heroic Quest for a Common and Inclusive Identity
Authors: Henzell‐Thomas Jeremy
Published: August 2004

It is Jeremy Henzell‐Thomas's conviction that the contemporary preoccupation with the so‐called ‘clash of civilizations’ is as ill‐founded as it is unhelpful. The assumption of an adversarial stance to which it leads is fuelled by, and affirms, a polarized thinking which does disservice to fundamental truths about unity and diversity. Drawing on theology and philosophy, he examines the etymology of key words –‘identity’, ‘authenticity’, ‘originality’, ‘fitra’ (nature) – to argue for the need to transcend difference in order to achieve (universal) identity. ‘We share a common identity as human beings, and, beyond that, a common origin within the source of Creation.’ If we are to honour the spiritual needs of young people and provide an education which is genuinely holistic, we need teachers who are prepared to listen to what young people are saying and to enter into a relationship with them that goes beyond the personal, the social and the moral.
Instantaneous Quantitative Video Intensity Heterogeneity: Evaluation with Low Mechanical Index Contrast Echocardiography
Authors: Bransford Toni L. , Bierig Serena Michelle , Habermehl Kathleen , Labovitz Arthur J.
Published: August 2004

Background: Instantaneous video intensity of myocardium has been poorly characterized. Myocardial video intensity is usually displayed in the fitted curve from the exponential equation, y = a(1 − e −bt). However, information from the fitted curve will be as accurate as the original video intensity data from the perfusion image. Therefore, we sought to characterize the intramyocardial instantaneous video intensity from low mechanical index (MI) contrast echo imaging for variation. Method: Low‐MI imaging using a nonlinear cancellation technique was performed on 10 subjects with normal myocardium. Quantitative video intensity was analyzed in five segments in the epicardium and subendocardium, as well as in systole and diastole. Results: Video intensity varied between the epicardium and endocardium in each of the region that was analyzed, with the greatest variation in the inferior region (P < 0.0001). Diastolic and systolic differences were also present. Conclusion: Instantaneous video intensity is heterogeneous within the myocardium. Differences can result from attenuation, myocardial fiber structure, and even isotropic effects of the contrast agent, and should be taken into account when data are fitted into an exponential function.
Improved Detection of Spontaneous Echo Contrast in the Aorta with Tissue Doppler Imaging
Authors: Leitman Marina , Sidenko Stanislav , Peleg Eli , Wolf Ruth , Sucher Edgar , Rosenblath Simha , Vered Zvi
Published: August 2004

Aims: Spontaneous echo contrast (SEC) within the cardiac chambers has been associated with increased risk of thromboembolism. We investigated the presence and severity of SEC in the aorta with tissue Doppler imaging (TDI) and compared these to the aortic flow velocity and to the clinical profile of the patients. Methods and Results: Seventy patients (35 males, 35 females, mean age 64, 22–86 years) underwent TEE for standard indications. Spontaneous echo contrast was studied with conventional and TDI imaging. Aortic flow velocity was measured in the center and lateral part of the descending aorta. SEC of any grade was detected in 24 patients with conventional imaging and in 53 using TDI (P < 0.0001). The presence of swirling was associated with aortic atherosclerosis, older age, history of hypertension and coronary artery disease, atrial fibrillation, and previous embolic events. There was correlation between intraaortic swirling, larger descending aortic diameter (23.6 vs 17 mm, P < 0.00001) and lower peak aortic flow velocity (55 vs 68 cm/s, P = 0.038). Conclusion: Spontaneous echo contrast in the aorta is common in high‐risk patients and is associated with increased clinical profile, larger aortic diameter, and lower peak aortic flow velocity. Tissue Doppler imaging is more sensitive in the detection of SEC than conventional imaging.
Live Three‐Dimensional Transthoracic Echocardiographic Assessment of Anomalous Origin of Left Coronary Artery from the Pulmonary Artery
Authors: Ilgenli T. Fikret , Nanda Navin C. , Sinha Ashish , Khanna Deepak
Published: August 2004

We describe live three‐dimensional transthoracic echocardiographic (3DTTE) findings in a 52‐year‐old female who had previously undergone an aortopulmonary tunnel operation for anomalous origin of the left coronary artery (ACA) from the pulmonary artery. Three‐dimensional transthoracic echocardiography clearly delineated the origin of the ACA from the posterolateral aspect of the main pulmonary artery just above the pulmonary valve, the surgically created tunnel, as well as a small defect in the tunnel near the aortic end communicating with the pulmonary artery.
‘Don't ask, don't tell’– the undesirable consequences of incidental test results in gastroenterology
Authors: Sonnenberg A.
Published: August 2004

A gastroenterologist is frequently approached to perform an endoscopic procedure after an incidental test has resulted in an unexpected positive finding. Should the incidental test result be ignored or automatically followed by an endoscopic procedure? The present analysis strives to characterize the common pattern of such scenarios and resolve their underlying dilemma. A model of game theory is used as a mathematical tool to develop general management strategies. Three clinical scenarios are used as examples to demonstrate this approach. The model is based on how doctors rank the various outcomes with which they are confronted by the incidental test results. The ranks of different outcomes are listed in a decision matrix that is converted into a two‐by‐two, non‐zero, ordinal game. All scenarios of incidental test results emerge as a similar type of game that is best played by both parties adhering to the same set of strategies: ‘Don't do the test’ and ‘don't respond to whatever test result it yields’. These two strategies lead to a Nash equilibrium for a non‐zero game, where neither party can improve its payoff any further by choosing a different strategy. Although the equilibrium does not provide the individual players with their best possible payoff, it yields the best overall outcome available to both parties given the economic and medical constraints of the situation.
Functional properties of biscuits with whey protein concentrate and honey
Authors: Conforti Paula Andrea , Lupano Cecilia Elena
Published: July 2004

The effects of honey, lemon juice, and two different whey protein concentrates (WPC) on the structural and functional properties of biscuits, were analysed. Firmness, elasticity, relaxation time, adhesiveness, consistency and cohesiveness of dough and colour, fracture stress and fracture strain of biscuits were also determined. The presence of WPC with a high protein content produced a decrease in the firmness and consistency and an increase in the cohesiveness of dough. Honey increased the adhesiveness of dough, mainly in samples with the WPC of lower protein content and lemon juice, and tended to decrease dough relaxation time. The fracture stress of biscuits decreased with the incorporation of WPC. Also, honey increased the red undertone and yellowness of biscuits and decreased their lightness; however, the addition of lemon juice reduced these effects.
A review of theoretical and practical aspects of solid‐phase microextraction in food analysis
Authors: Wardencki Waldemar , Michulec Magdalena , Curyło Janusz
Published: July 2004

Solid‐phase microextraction (SPME) is a modern, solvent‐free sample preparation technique, commonly used in trace analysis. This technique has been developed to combine sampling and sample preparation in one step. This paper reviews selected theoretical and practical aspects of the SPME method used for the isolation and preconcentration of impurities, food constituents, additives and flavour compounds in food samples. The main parameters affecting the extraction effectiveness are discussed and exemplified by selected chromatograms. The review is intended for readers who are either new to the field of SPME or its use in food analysis and many examples of its application for different food matrices are listed.
Hot air dehydration of figs (Ficus carica L.): drying kinetics and quality loss
Authors: Piga Antonio , Pinna Ivo , Özer Kamer B. , Agabbio Mario , Aksoy Uygun
Published: July 2004

The dehydration of fruit from fig trees is normally achieved by sun drying. There is concern about the safety of the end product, mainly because there is a risk of the development of aflatoxins. These concerns can be overcome by artificial drying (oven dehydration). Fig fruits of a local cultivar, which were either pre‐treated by blanching or blanching plus sulphuring or not treated at all, underwent hot air dehydration under mild processing conditions in a pilot airflow cabinet dryer. Sampling was carried out at regular intervals to calculate the rate of dehydration and assess quality changes. Microbiological counts and nonenzymatic browning were also monitored. Pretreatments resulted in a shorter processing time, compared with control fruits. In general, a falling dehydration rate period was observed. A dramatic loss of ascorbic acid was recorded, while an informal sensorial assay of the dried fruits gave a positive assessment.
Post‐translational regulation of phosphatidylglycerolphosphate synthase in response to inositol
Authors: He Quan , Greenberg Miriam L.
Published: August 2004

Phosphatidylglycerolphosphate synthase (Pgs1p) catalyses the committed step in the synthesis of cardiolipin (CL). This is the only step of CL synthesis that is regulated by inositol. We have shown previously that Pgs1p enzyme activity is decreased within minutes after supplementation with inositol, but PGS1 expression is unaltered. We utilized an epitope‐tagged Pgs1p to determine if the rapid decrease in activity following inositol was because of degradation or inactivation of the protein. In this report, we show that, in response to inositol, the decrease in CL content and Pgs1p enzyme activity are associated with increased phosphorylation of Pgs1p, but not with degradation or mislocalization of the protein. This is the first evidence of phosphorylation of a phospholipid biosynthetic enzyme in response to inositol and identifies a new mechanism of inositol‐mediated regulation.
Physiological growth is associated with esophageal morphometric and biomechanical changes in rats
Authors: Gregersen Hans , Lu Xiao , Zhao Jingbo
Published: August 2004

Abstract  Esophageal geometry and biomechanical changes were studied during physiological growth in rats aged 1–32 weeks. Histological examination was done after the biomechanical study. The esophageal dimensions increased many‐fold from 1–32 weeks, e.g. the weight per unit length increased six‐fold and the wall cross‐sectional area increased eight‐fold. The inner and outer circumferential length of the mucosa and muscle, and the thickness and area of the layers increased as function of age. The opening angle was approximately 140 degrees at age 1 and 2 weeks and gradually decreased to approximately 80 degrees after 16 weeks. The circumferential and longitudinal stress–strain curves were exponential. The circumferential stress–strain curves shifted from left to the right up to 4 weeks of age (P < 0.001) where after no further change was observed, i.e. the esophagus became more compliant during the first 4 weeks of life. The longitudinal stress–strain curves shifted from left to the right up to 16 weeks of age (P < 0.001), i.e. the esophagus became more compliant longitudinally during the first 16 weeks of life. Bi‐axial stress–strain analysis with determination of mechanical tissue constants showed that the esophagus was stiffer in the longitudinal direction than in the circumferential direction. In conclusion, a pronounced morphometric and biomechanical remodelling was observed in the rat esophagus during physiological growth. The observed changes likely reflect the development of the physiological function of the esophagus since for other tissues the function dictates the form of the tissue, and growth and remodelling depend on the mechanical loading.
Effect of ghrelin and growth hormone‐releasing peptide 6 on septic ileus in mice
Authors: De Winter B. Y. , De Man J. G. , Seerden T. C. , Depoortere I. , Herman A. G. , Peeters T. L. , Pelckmans P. A.
Published: August 2004

Abstract  Ghrelin is an orexigenic peptide with prokinetic effects in the rat. We investigated the effect of ghrelin and growth hormone‐releasing hormone 6 (GHRP‐6) on gastric emptying and transit in control and septic mice. Mice were injected i.p. with lipopolysaccharides (LPS) or saline (control). After 16–17 h mice were pretreated with saline, ghrelin or GHRP‐6 1 h before intragastric administration of Evans blue. Fifteen minutes later, after assessment of the behaviour scale, mice were killed and gastric emptying, transit and rectal temperature were measured. In control mice, ghrelin (100 μg kg−1) and GHRP‐6 (20–100 μg kg−1) accelerated gastric emptying, whereas ghrelin and GHRP‐6 failed to increase transit significantly. Septic mice developed a delay in gastric emptying and transit, hypothermia and a deterioration of the behaviour scale. In septic mice, ghrelin (20 μg kg−1) accelerated gastric emptying without effect on transit while GHRP‐6 significantly accelerated gastric emptying dose‐dependently and failed to increase transit significantly. Ghrelin and GHRP‐6 had no effect on the endotoxin‐induced hypothermia or deterioration of behaviour scale. Therefore, the beneficial prokinetic effect of ghrelin but mainly of GHRP‐6 offers potential therapeutic options in the treatment of septic gastric ileus.
Character of sediments entering the Costa Rica subduction zone: Implications for partitioning of water along the plate interface
Authors: Spinelli Glenn A. , Underwood Michael B.
Published: July 2004

Abstract  Sediments deposited off the Nicoya Peninsula advect large volumes of water as they enter the Costa Rica subduction zone. Seismic reflection data, together with results from Ocean Drilling Program Leg 170, show that hemipelagic mud comprises the upper ∼135 m of the sediment column (ranging from 0 to 210 m). The lower ∼215 m of the sediment column (ranging from 0 to 470 m) is pelagic carbonate ooze. We analyzed samples from 60 shallow (<7 m) cores to characterize the spatial variability of sediment composition on the incoming Cocos Plate. The bulk hemipelagic sediment is 10 wt% opal and 60 wt% smectite on average, with no significant variations along strike; the pelagic chalk contains approximately 2 wt% opal and <1 wt% smectite. Initially, most of the water (96%) in the subducting sediment is stored in pore spaces, but the pore water is expelled during the early stages of subduction by compaction and tectonic consolidation. Approximately 3.6% of the sediment's total water volume enters the subduction zone as interlayer water in smectite; only 0.4% of the water is bound in opal. Once subducting strata reach depths greater than 6 km (more than 30 km inboard of the subduction front), porosity drops to less than 15%, and temperature rises to greater than 60°C. Under those conditions, discrete pulses of opal and smectite dehydration should create local compartments of fluid overpressure, which probably influence fluid flow patterns and reduce effective stress along the plate boundary fault.
Optimal Tariffs and Subsidies and Changes in Market Structure
Authors: Egli Dominik , Westermann Frank
Published: August 2004

The paper presents a unified treatment of optimal trade policy for a small country. The well‐known results for duopoly and competitive markets emerge as benchmark cases of the authors’ model. In addition, it is shown that changes in market structure have nonmonotonic effects on optimal tariffs. The results suggest that the recent reduction of tariffs in eastern Europe is consistent with welfare‐maximizing trade policy in response to the substantial changes in the market structure of these countries.
Income Distribution, Learning‐by‐Doing, and Comparative Advantage
Authors: Mani Anandi , Hwang Jinyoung
Published: August 2004

The paper examines the impact of the income distribution in a less‐developed country (LDC) on its patterns of trade, through its influence on home market demand patterns. In a learning‐by‐doing model with nonhomothetic preferences, the authors show that import substitution under low inequality generates more focused learning and enhances trade potential more effectively. In addition, relative wages under trade are higher in a low‐inequality LDC. The model predicts that high‐inequality LDCs are more likely to remain exporters of unskilled/low‐skilled goods, whereas low‐inequality LDCs are more likely to mature into simple manufactures and beyond—a prediction that is consistent with world trade patterns of LDCs. The authors present descriptive and empirical evidence in support of this link between income inequality, domestic demand patterns, and dynamic comparative advantage.
A Swedish translation and validation of the Disgust Scale: A measure of disgust sensitivity
Authors: BJÖRKLUND FREDRIK , HURSTI TIMO J.
Published: July 2004

The psychometric properties of a Swedish version ofHaidt, McCauley and Rozin's (1994)Disgust Scalewere studied. Confirmatory factor analysis of the original model with eight factors (food, animals, body products, sex, body envelope violations, death, hygiene, and magic) provided satisfactory fit to the data (N= 280), significantly better than to the alternative one‐factor and five‐factor models. As in the US version women scored significantly higher than men. Positive correlations with measures of food neophobia (r= 0.30,p< 0.0001) and nausea frequency (rs= 0.28,p< 0.001) indicate convergent validity. In a separate study (N= 30) a behavioral measure of the willingness to touch, hold, and taste disgusting food objects correlated negatively with the Disgust Scale (r=−0.46,p< 0.01), indicating criterion‐related validity.
Behavioral and social development of children born extremely premature: 5‐year follow‐up
Authors: HOFF BARBARA , HANSEN BO MØLHOLM , MUNCK HANNE , MORTENSEN ERIK LYKKE
Published: July 2004

A cohort of extremely prematurely born children and matched term controls was assessed at 5 years of age. The parents completed a questionnaire on their behavioral and social development. The purpose was to illuminate whether the children's general intellectual ability and parental sensitivity were associated with behavioral and social development. The index children exhibited more hyperactive behavior and had poorer social skills than the controls. Lower Full Scale IQ (FSIQ) was associated with outward reacting and hyperactive behavior and poorer social skills. Sensitive parenting was associated with less outward reacting and less hyperactive behavior. When controlling for differences in FSIQ and parental sensitivity, the index children persisted to have an increased risk of exhibiting hyperactive behavior but not poorer social skills. The index children with normal intellectual development, however, did not exhibit more behavioral problems or poorer social skills than the control children did.
Appraised psychological workload, musculoskeletal symptoms, and the mediating effect of fatigue: A structural equation modeling approach
Authors: BYSTRÖM PERNILLA , HANSE JAN JOHANSSON , KJELLBERG ANDERS
Published: July 2004

The aim of the present study was to test two structural models of the relationship between appraised psychological workload and musculoskeletal symptoms from the neck, shoulder, and upper and lower back with different aspects of perceived fatigue as mediating variables. In this cross‐sectional study a questionnaire survey was conducted among employees at three Swedish assembly plants (n= 305). The proposed models were tested for one general fatigue dimension – lack of energy – and four specific fatigue dimensions – physical discomfort, physical exertion, lack of motivation, and sleepiness – using structural equation modeling. The results indicate that the role of perceived fatigue in the relationship between appraised workload and musculoskeletal symptoms is different for different aspects of fatigue. The general fatigue dimension, lack of energy, does not mediate the relationship. As regards the specific fatigue dimensions, the relationship is partially mediated by physical discomfort and lack of motivation but not by physical exertion or sleepiness. Appraised psychological workload has a unique effect on musculoskeletal symptoms not mediated by fatigue.
Does Commuting Reduce Wage Disparities?
Authors: Hazans Mihails
Published: July 2004

ABSTRACT  This paper shows that in the Baltic countries, commuting reduces urban‐rural wage and employment disparities and increases national output. To quantify the effect of commuting on wage differentials, two sets of earnings functions are estimated (based on Estonian, Latvian, and Lithuanian Labor Force Surveys) with location variables (capital city, rural, etc.) measured at the workplace and at the place of residence. We find that the ceteris paribus wage gap between capital city and rural areas, as well as between capital and other cities is significantly narrowed by commuting in some cases but remains almost unchanged in others. Different outcomes are explained by country‐specific spatial patterns of commuting, educational and occupational composition of commuting flows, and presence or absence of wage discrimination against rural residents in urban markets. A treatment effects model is used to estimate individual wage gains to rural—urban or inter‐city commuting; these gains are substantial in most but not all cases. Wage effects of commuting distance, as well as impact of education, gender, ethnicity, and local labor market conditions on the commuting decision are also explored.
In vivo mechanisms of vascular endothelial growth factor‐mediated increased hydraulic conductivity of Rana capillaries
Authors: Pocock T. M. , Bates D. O.
Published: August 2004

Vascular endothelial growth factor (VEGF) increases hydraulic conductivity (Lp) in vivo. To determine the signal transduction cascade through which this is mediated, we measured the effect of inhibition of various signalling pathways on VEGF‐mediated acute increases in Lp in individually perfused frog mesenteric microvessels.

VEGF receptors have previously been shown to activate phospholipase C‐γ (PLCγ), protein kinase C (PKC) and MEK, the mitogen‐activated and extracellular signal‐related kinase (ERK) kinase. To determine the role of these signalling pathways we measured the effects of inhibitors of each on the VEGF‐mediated increase in Lp.

VEGF‐mediated increases in Lp were attenuated by pre‐treatment with the PLC inhibitor U73122, but not affected by treatment with the inactive enantiomer U73343. The PLC inhibitor was also able to attenuate the increase in Lp mediated by the inflammatory mediator ATP.

Inhibition of either PKC or MEK activation using the selective inhibitors bisindolylmaleimide (BIM, 1 μm) and PD98059 (30 μm), respectively, did not change the VEGF‐mediated increase in Lp. However, PD98059, BIM and U73122 all reduced phosphorylation of ERK1/2 determined by Western blot analysis with anti‐phospho‐ERK1/2 antibodies.

Furthermore, inhibition of the conversion of diacyl glycerol (DAG) to arachidonic acid, by perfusion with the DAG lipase inhibitor RHC80267 (50 μm), did not attenuate the increase in Lp brought about by VEGF.

These data suggest that VEGF acutely increases microvascular permeability in vivo through a mechanism that is dependent on PLC stimulation, but is independent of PKC or MEK activation or production of arachidonic acid from DAG. We therefore propose that VEGF acutely acts to increase Lp through the direct actions of DAG, independently of PKC or arachidonic acid.
Transmural differences in rat ventricular protein kinase C epsilon correlate with its functional regulation of a transient cardiac K+ current
Authors: Thorneloe K. S. , Liu X. F. , Walsh M. P. , Shimoni Y.
Published: August 2004

The effects of PKC activation on a transient (It) and a sustained (Iss) cardiac K+ current and the subcellular distribution of the epsilon isoform of PKC (PKCε) were compared in epicardial and endocardial regions of the rat ventricle.

Activation of PKCε with a diacylglycerol analogue (di‐octanoyl‐glycerol (DiC8), 20 μm) leads to differential effects in epicardial and endocardial cells. In epicardial cells (n = 20) It and Iss are attenuated by 17.7 ± 2.1 % and 11.9 ± 3.1 %, respectively (means ±s.e.m.). In endocardial cells It attenuation was significantly smaller (4.6 ± 1.6 %, n = 14, P < 0.0005). Iss attenuation was similar to that in epicardial cells (10.5 ± 3.8 %).

PKCε expression was measured by Western blotting. Calculated endocardial/epicardial ratios showed no regional differences in total protein extracts (1.04 ± 0.11, mean ±s.e.m, n = 4), but PKCε distribution in the cytosolic fraction showed a marked difference, with significantly (P < 0.05) higher levels in endocardial extracts. The cytosolic endocardial/epicardial PKCε ratio was 2.64 ± 0.24 (n = 4), indicating a reduced amount of PKCε in the membrane fraction of the endocardium. This could account for the reduced effect of DiC8 on It in endocardial myocytes.

Under both hypothyroid and streptozotocin‐induced diabetic conditions the difference in endocardial and epicardial cytosolic PKCε levels was absent (ratios of 0.86 ± 0.21 (n = 4) and 1.09 ± 0.16 (n = 3), respectively; means ±s.e.m.). Ratios in the total protein extracts were not significantly different from those in control conditions.

The results show transmural differences in the functional effects of PKCε activation on a cardiac K+ current, and in the subcellular distribution of PKCε. These differences are absent in diabetic and hypothyroid conditions.
Adaptive changes in locomotor control after partial denervation of triceps surae muscles in the cat
Authors: Gritsenko Valeriya , Mushahwar Vivian , Prochazka Arthur
Published: August 2004

This report concerns a test of the hypothesis that gain in the stretch reflex pathway of cat medial gastrocnemius (MG) muscle during locomotion increases after denervation of its synergists, lateral gastrocnemius (LG), soleus (SOL) and plantaris (PL) muscles.

In four cats, MG, tibialis anterior (TA) and vastus lateralis (VL) muscles were implanted with electromyogram (EMG) electrodes. The cats walked on a row of elevated pegs, some of which were spring‐loaded and could be triggered to pop up at the moment of foot touchdown, rapidly dorsiflexing the foot. Pre‐stretch EMG activity in MG as well as short‐, medium‐ and long‐latency responses to the dorsiflexions were compared before and after unilateral denervation of synergists.

Short‐ and medium‐latency responses of MG to perturbations increased in proportion to the increase in pre‐stretch EMG in the days and weeks after partial denervation. This argues against an adaptive increase in stretch reflex gain independent of centrally generated extensor drive.

Local anaesthesia of the skin of the paw did not significantly change the sizes of the stretch responses of MG before or after partial denervation.

We conclude that pre‐stretch EMG activity as well as stretch reflexes in MG muscle increased substantially after denervation of synergistic muscles. The data were consistent with an adaptive increase in central locomotor drive, causing more motoneuronal activity, which in turn resulted in an increase in the size of stretch reflexes.
Kinetic modification of the α1I subunit‐mediated T‐type Ca2+ channel by a human neuronal Ca2+ channel γ subunit
Authors: Green P. J. , Warre R. , Hayes P. D. , McNaughton N. C. L. , Medhurst A. D. , Pangalos M. , Duckworth D. M. , Randall A. D.
Published: August 2004

Voltage‐sensitive Ca2+ channels (VSCCs) are often heteromultimeric complexes. The VSCC subtype specifically expressed by skeletal muscle has long been known to contain a γ subunit, γ1, that is only expressed in this tissue. Recent work, initiated by the identification of the mutation present in the stargazer mouse, has led to the identification of a series of novel potential Ca2+ channel γ subunits expressed in the CNS.

Based on bioinformatic techniques we identified and cloned the human γ2, γ3 and γ4 subunits.

TaqMan analysis was used to quantitatively characterise the mRNA expression patterns of all the γ subunits. All three subunits were extensively expressed in adult brain with overlapping but subunit‐specific distributions. γ2 and γ3 were almost entirely restricted to the brain, but γ4 expression was seen in a broad range of peripheral tissues.

Using a myc epitope the γ2 subunit was tagged both intracellularly at the C‐terminus and on a predicted extracellular site between the first and second transmembrane domains. The cellular distribution was then examined immunocytochemically, which indicated that a substantial proportion of the cellular pool of the γ2 subunit was present on the plasma membrane and provided initial evidence for the predicted transmembrane topology of the γ subunits.

Using co‐transfection techniques we investigated the functional effects of each of the γ subunits on the biophysics of the T‐type VSCC encoded by the α1I subunit. This revealed a substantially slowed rate of deactivation in the presence of γ2. In contrast, there was no significant corresponding effect of either γ3 or γ4 on α1I subunit‐mediated currents.
Differences between nerve terminal impulses of polymodal nociceptors and cold sensory receptors of the guinea‐pig cornea
Authors: Brock James A. , Pianova Svetlana , Belmonte Carlos
Published: August 2004

Extracellular recording techniques were used to study nerve terminal impulses (NTIs) recorded from single polymodal nociceptors and cold‐sensitive receptors in guinea‐pig cornea isolated in vitro.

The amplitude and time course of NTIs recorded from polymodal nociceptors was different from those of cold‐sensitive receptors.

Bath application of tetrodotoxin (1 μm) changed the time course of spontaneous NTIs recorded from both polymodal and cold‐sensitive receptors.

Bath application of lignocaine (lidocaine; 1–5 mm) abolished all electrical activity.

Local application of lignocaine (2.5 and 20 mm) through the recording electrode changed the time course of the NTIs recorded from polymodal nociceptors but not that of NTIs recorded from cold‐sensitive nerve endings.

It is concluded that action potentials propagate actively in the sensory nerve endings of polymodal nociceptors. In contrast, cold‐sensitive receptor nerve endings appear to be passively invaded from a point more proximal in the axon where the action potential can fail or be initiated.