bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sphingosylphosphocholine effects on cultured astrocytes reveal mechanisms potentially involved in neurotoxicity in Niemann‐Pick type A disease
Authors: Chiulli Nino , Codazzi Franca , Di Cesare Alessandra , Gravaghi Claudia , Zacchetti Daniele , Grohovaz Fabio 
Published: July 2007

AbstractNiemann‐Pick type A is a disease characterized by the absence of a functional SMPD1 (acidic sphingomyelinase) gene and the abnormal accumulation of sphingomyelin. Under these conditions, also sphingosylphosphocholine (SPC, a sphingomyelin metabolite) accumulates in various tissues, including the brain, where it might act as a toxic stimulus, contributing to the appearance of the neurological symptoms. We studied the effects of SPC on astrocytic and neuronal cultures from rat. In particular, we investigated the possibility that SPC acts on astrocytes and that this represents the first step leading to neurodegeneration. Our results show that acute administration of SPC to astrocytes in culture promotes Ca2+ responses and a release of glutamate that, in turn, leads to cytosolic [Ca2+] elevation in neurons. We also show that chronic stimulation by SPC leads astrocytes to proliferate, but can also change their phenotype towards an activated state that might contribute to the inflammatory responses. Interestingly, upon acute SPC stimulation, activated astrocytes release more glutamate. In conclusion, we show that both chronic and acute exposure to SPC can constitute harmful signals that may have a role in the sequence of events leading to neurodegeneration.
Increase of serum C‐reactive protein is an early indicator of subsequent symptomatic anastomotic leakage after anterior resection
Authors: Matthiessen P. , Henriksson M. , Hallböök O. , Grunditz E. , Norén B. , Arbman G. 
Published: July 2007

AbstractObjective  This prospective study investigated the factors which might indicate anastomotic leakage after low anterior resection.Method  Thirty‐three patients who underwent anterior resection for rectal carcinoma (n = 32) and severe dysplasia (n = 1), were monitored daily by serum C‐reactive protein (CRP) and white blood cell count (WBC) estimations until discharge from hospital. Computed tomography (CT) scans were performed on postoperative days 2 and 7 and the amount of presacral fluid collection was assessed. All patients had a pelvic drain and the volume of drainage was measured daily.Results  The level of the anastomosis was at a median 5 cm (3–12 cm) above the anal verge. There was no 30‐day mortality. Nine (27.2%) of the 33 patients developed a symptomatic anastomotic leakage which was diagnosed at a median of 8 days (range 4–14) postoperatively. The serum CRP was increased in patients who leaked from postoperative day 2 onwards (P = 0.004 on day 2; P < 0.001 on day 3–8). The WBC was decreased in preoperatively irradiated patients on days 1–5 (P ≤ 0.021), with no difference seen between patients with or without leakage. Patients with leakage had a larger presacral fluid collection on CT on day 7 (median 76 ml vs 52 ml; P = 0.016) and a larger increase in the fluid collection between the first and the second CT examinations (28 ml vs 3 ml; P = 0.046).Conclusion  An early rise in serum CRP was a strong indicator of leakage. Monitoring of CRP for possible early detection of symptomatic anastomotic leakage is recommended.
MANAGEMENT BUYOUTS, SUPERVISION AND EMPLOYEE DISCRETION
Authors: Amess Kevin , Brown Sarah , Thompson Steve 
Published: July 2007

ABSTRACTUsing a matched sample of 1959 firms and 27,263 employees from the UK Workplace Employee Relations Survey, we examine the effects of the management buyout (MBO) organizational form on employee discretion and supervision. Our findings suggest that for MBO firms, supervision is lower where there is a higher proportion of craft and skilled service workers but is not lower for other occupational groups. Using random effects ordered probit analysis, we find that employees' discretion over their work practices is higher in MBO firms; and that the probability of higher discretion is greater where there is a higher proportion of craft and skilled service employees. Our findings are consistent with: (i) MBOs reducing hierarchical tiers and the number of supervisory staff, which increase employees' span of control and their discretion; and (ii) organizational change via an MBO being ‘skill biased’ in favour of craft and skilled service employees.
OUTPUT AND INFLATION IN MODELS OF THE BUSINESS CYCLE WITH NOMINAL RIGIDITIES: FURTHER COUNTERFACTUAL IMPLICATIONS
Authors: Páez‐Farrell Juan 
Published: July 2007

ABSTRACTThis paper examines the relationship between cyclical output and inflation in models commonly used for monetary policy analysis. This includes models that incorporate the New Keynesian, Fuhrer–Moore and backward‐looking Phillips curves. The main finding is that these models imply a strong negative relationship between inflation and output, a result that is at odds with the data. The fact that New Keynesian models yield counterfactual implications is not new; the novelty of the paper lies in the fact that the finding extends to the other variants, such as the backward‐looking Phillips Curve, which have been put forward as displaying superior dynamics.
INEQUALITY AND GROWTH: FROM MICRO THEORY TO MACRO EMPIRICS
Authors: Gobbin Niko , Rayp Glenn , Van de gaer Dirk 
Published: July 2007

ABSTRACTWe show that the way individual income data should be aggregated into an index of inequality in order to explain countries' growth performance is theory specific. A simulation set‐up shows that the use of a wrong measure might obscure the inequality–growth relationship and that the relative performance of different measures of inequality can be informative about the channel through which inequality influences economic growth.
OCCUPATIONAL PENSIONS, WAGES, AND JOB MOBILITY IN GERMANY
Authors: Rabe Birgitta 
Published: July 2007

ABSTRACTPension‐covered workers in Germany are three times less likely to change jobs than workers not covered by an occupational pension scheme. This paper examines the effects of occupational pension coverage and pension portability loss on voluntary job changes using a sample selection model with endogenous switching. The model estimates, derived from western German panel data for 1985–1998, indicate that occupational pension coverage reduces worker mobility by imposing a capital loss on those leaving their job before retirement age. Moreover, pension‐covered workers receive a higher compensation, which discourages mobility. Making pensions portable increases mobility, but from a low initial level.
KEEPING UP WITH THE JONESES, GROWTH, AND DISTRIBUTION
Authors: Tsoukis Chris 
Published: July 2007

ABSTRACTA recent class of models on ‘keeping up with the Joneses’ suggests that comparison with the consumption of other individuals affects individual utility. This paper nests three variants of the ‘Joneses’ effect into an otherwise standard growth model. Under some conditions, growth and distribution are jointly determined, presenting thus a unification of the relevant theories. These variants are however not equivalent in terms of their effects on growth and distribution. It is also shown that, at least if comparisons‐in‐mean predominate, rises in the mean skills level and in the exogenous skills variance increase both growth and inequality with ambiguous effects on aggregate welfare.
The time course of building discourse coherence in schizophrenia: An ERP investigation
Authors: Ditman Tali , Kuperberg Gina R. 
Published: July 2007

AbstractImpairments in the buildup and use of context may lead to disorders of thought and language in schizophrenia. To test this hypothesis, event‐related potentials (ERPs) were measured while patients and healthy controls read sentences that were highly causally related, intermediately related, or unrelated to preceding contexts. Although patients were slower than controls, both groups used the discourse context similarly as evidenced by similar reaction time patterns across conditions. Neurally however, different patterns emerged between patients and controls: within the N400 time window, patients failed to modulate their neural responses across conditions. This failure to differentiate between conditions was specifically correlated with positive thought disorder. Results suggest that schizophrenia patients, particularly those with positive thought disorder, fail to make immediate use of discourse context to build up semantic coherence in the brain.
It's worse than you thought: The feedback negativity and violations of reward prediction in gambling tasks
Authors: Hajcak Greg , Moser Jason S. , Holroyd Clay B. , Simons Robert F. 
Published: July 2007

AbstractThe reinforcement learning theory suggests that the feedback negativity should be larger when feedback is unexpected. Two recent studies found, however, that the feedback negativity was unaffected by outcome probability. To further examine this issue, participants in the present studies made reward predictions on each trial of a gambling task where objective reward probability was indicated by a cue. In Study 1, participants made reward predictions following the cue, but prior to their gambling choice; in Study 2, predictions were made following their gambling choice. Predicted and unpredicted outcomes were associated with equivalent feedback negativities in Study 1. In Study 2, however, the feedback negativity was larger for unpredicted outcomes. These data suggest that the magnitude of the feedback negativity is sensitive to violations of reward prediction, but that this effect may depend on the close coupling of prediction and outcome.
A way of seeing study abroad: narratives from nurse education
Authors: Greatrex‐White Sheila 
Published: July 2007

AbstractThis paper reports on the findings of a phenomenological study of nursing students studying abroad. The literature shows that study abroad has long been part of liberal educational approaches dating back to medieval times. Yet it is only recently that undergraduate nursing students have been allowed to study abroad as part of their formal programme. The research conducted was informed by the philosophical hermeneutic phenomenology of Martin Heidegger and was designed to answer the question: ‘How is study abroad manifest in the experience of nursing students?’ Data were collected through the use of unstructured diaries of 26 nursing students studying at two universities in the United Kingdom. Analysis uncovered six structures or ‘ways for study abroad to be’: leaving behind, escape, foreigner, learning, self‐discovery and risk. The main focus of this paper is ‘leaving behind’; the selection of this structure reflects its general interest and predominance in data analysis. Interpretation of the structure suggests that study abroad might offer an opportunity to militate against the limiting effects of personal and professional socialization processes. Here, socialization is viewed as a state of becoming and study abroad for some nursing students is a facet of this state of becoming. Finally, it is argued that study abroad is deserving of much greater attention in nurse education and beyond. For example, the concepts of global communities and a global economy necessitate the need for employees in the future to have wider experiences and understanding of different cultures and understanding the experience of study abroad is one possible contribution to this. Thus, it is believed that this study makes a valuable contribution to teaching and learning discourses, specifically nurse education and also in wider educational arenas.
Elevated Homocysteine Levels in Patients with Slow Coronary Flow: Relationship with Helicobacter pylori Infection
Authors: Evrengul Harun , Tanriverdi Halil , Kuru Omur , Enli Yasar , Yuksel Dogangun , Kilic Ayhan , Kaftan Asuman , Kirac Suna , Kilic Mustafa 
Published: July 2007

AbstractBackground and objective:  Elevation of plasma homocysteine (Hcy) level has been implicated in the pathogenesis of slow coronary flow (SCF) as it can severely disturb vascular endothelial function. Helicobacter pylori chronically infect the human stomach and causes malabsorption of vitamin B12 and folate in food, leading ultimately to an increase in circulating Hcy levels.Methods:  Forty‐three patients with angiographically proven SCF (group I) were enrolled in this study; 43 cases with normal coronary flow pattern (group II) served as controls. Fasting plasma levels of Hcy, vitamin B12, and folate were measured in all subjects. Presence of H. pylori infection was defined as positive 14 C urea breath test. Coronary flow patterns for each major epicardial coronary artery were determined with the Thrombolysis in Myocardial Infarction (TIMI) frame count method.Results:  Mean TIMI frame count was 46.3 ± 8.7 in group I and 24.3 ± 2.9 in Group II (p = .0001). Vitamin B12 levels were similar, whereas folate levels were dramatically reduced in group I compared to group II (13.2 ± 4.3 vs. 17.1 ± 5.2, p = .0001). Plasma Hcy levels were significantly higher in group I compared to group II (13.4 ± 5.6 vs. 7.9 ± 2.5, p = .0001) as was the prevalence of H. pylori infection (90.7% in group I vs. 58.1% in group II, p = .001). Hcy levels were elevated (11.7 ± 5.3 vs. 7.5 ± 2.7, p = .0001) and folate levels were reduced (13.9 ± 4.7 vs. 18.6 ± 4.9, p = .0001) in patients with H. pylori infection, while vitamin B12 levels were similar in patients with and without H. pylori infection. Correlation analysis revealed a significant negative correlation between plasma folate and Hcy levels and also between folate levels and mean TIMI frame counts (r = –.33, p = .002 vs. r = –.33, p = .003). Moreover, there was a significant positive correlation between plasma Hcy levels and mean TIMI frame counts (r = .66, p = .0001). In addition, the folate level was the only significant determinant of the variance of Hcy in multiple regression analysis (r = –.21, p = .03).Conclusion:  Our data showed that plasma folate levels were decreased and plasma Hcy levels were increased in patients with SCF compared to controls. Also, the prevalence of H. pylori infection was increased in patients with SCF. These findings suggest that elevated levels of plasma Hcy, possibly caused by H. pylori infection, and/or a possible disturbance in its metabolism may play a role in the pathogenesis of SCF.
Helicobacter pylori Colonization in the First 3 Years of Life in Japanese Children
Authors: Okuda Masumi , Miyashiro Eikichi , Booka Mina , Tsuji Tomomi , Nakazawa Teruko 
Published: July 2007

AbstractBackground:  Acquisition of Helicobacter pylori infection occurs in early childhood, but the exact time of the acquisition and dynamics of infection are not clear. The aim of this study was to estimate the time of acquisition of H. pylori colonization in infants.Subjects and methods:  This prospective follow‐up study included 237 infants born in Wakayama Rosai Hospital from February, 2001 to April, 2002. Stool samples were collected at indicated ages, and H. pylori antigens were determined by a stool antigen test, HpSA.Results:  One‐hundred and eight infants among initially enrolled 237 children have been followed up until 24 months. Among these, 16 infants turned to be HpSA positive within 12 months, but only four remained positive by the consecutive tests with optical density values of more than 0.7. They were assumed persistent positives. The rest 12 infants reverted to be negative by the consecutive tests and were assumed transient or false‐positives. The optical density values of HpSA in the transient cases were exclusively less than 0.35.Conclusions:  The consecutive follow up of HpSA, but not the one‐point test, might be useful to diagnose persistent colonization of H. pylori in young infants, and some infants seemed to acquire H. pylori infection in the first year of life. These results should be taken into account for prevention and treatment strategies for H. pylori infection in infants.
A Review of the Postulated Mechanisms Concerning the Association of Helicobacter pylori with Ischemic Heart Disease
Authors: Manolakis Anastassios , Kapsoritakis Andreas N. , Potamianos Spiros P. 
Published: July 2007

AbstractSince its discovery, Helicobacter pylori has been implicated in the pathogenesis of several diseases, both digestive and extradigestive. Interestingly, the majority of the extradigestive‐related literature is focused on two vascular manifestations: stroke and ischemic heart disease. Potential mechanisms for the establishment of a H. pylori‐induced ischemic heart disease have been proposed with regard to chronic inflammation, molecular mimicry, oxidative modifications, endothelial dysfunction, direct effect of the microorganism on atherosclerotic plaques as well as changes regarding traditional or novel risk factors for ischemic heart disease or even platelet‐H. pylori interactions. A positive link between H. pylori infection and ischemic heart disease has been suggested by a series of studies focusing on epidemiologic evidence, dyslipidemic alterations, upregulation of inflammatory markers or homocysteine levels, induction of hypercoagulability, oxidation of low‐density lipoprotein, causation of impaired endothelial function, detection of H. pylori DNA in atherosclerotic plaques, and participation of certain antigens and antibodies in a cross‐reactivity model. There are studies, however, which investigated the relationship between H. pylori and ischemic heart disease with regard to the same parameters and failed to confirm the suggested positive association. Further studies in the direction of interaction between H. pylori and the host's genotype as well as a quest for evidence towards novel risk factors for ischemic heart disease such as oxidative stress, vascular remodeling, vascular calcification, or vasomotor activity, may reveal a field of great interest, thus contributing to the determination of new potential mechanisms.
Idiopathic Generalized Epilepsy with Absences: Syndrome Classification
Authors: Valentin Antonio , Hindocha Neeti , Osei‐Lah Abeena , Fisniku Leonora , McCormick David , Asherson Phillip , Moran Nicholas , Makoff Andrew , Nashef Lina 
Published: July 2007

Summary In a cohort of 275 Caucasians with a broad IGE phenotype, patients with absences were classified. Criteria of the 1989 Commission on Classification of the International League Against Epilepsy for Childhood Absence Epilepsy (CAE 1989 criteria) were compared with the stricter criteria of the ILAE Task Force for Classification and Terminology (CAE 2005 criteria). Among the 129 patients with absences without significant myoclonus, 50 had juvenite absence epilepsy 44 had CAE according to the CAE 1989 criteria and only 30 had CAE according to the CAE 2005 criteria. We found a significantly better outcome in patients considered as CAE by the CAE 2005 criteria, compared with those excluded. Strict criteria for classification of absence syndromes leave many patients unclassified. However, diagnostic criteria used to classify CAE patients have prognostic significance. We propose that patients are classified as having benign CAE or as having CAE with the adverse prognostic factors indicated.
Focal Increases in Perfusion and Decreases in Hemoglobin Oxygenation Precede Seizure Onset in Spontaneous Human Epilepsy
Authors: Zhao Mingrui , Suh Minah , Ma Hongtao , Perry Challon , Geneslaw Andrew , Schwartz Theodore H. 
Published: July 2007

Summary
Purpose: Optical recording of intrinsic signals provides the highest combined spatial and temporal resolution with broad spatial sampling for measuring cerebral blood volume (CBV) and hemoglobin oxygenation in cerebral cortex. Few opportunities arise to apply this laboratory method to record spontaneous seizures in unanesthetized human brain during neurosurgery. We report such a rare opportunity in a man with recurrent focal epilepsy arising from a cavernous malformation.
Methods: We recorded intrinsic optical signals (IOS) from human cortex intraoperatively during spontaneous seizures arising from brain surrounding a small cavernous malformation in an awake patient using only local anesthesia with simultaneous electrocorticography. The IOS was recorded at two wavelengths, one an isosbestic point for hemoglobin to measure CBV (570 nm) and the other at a wavelength more sensitive to deoxygenated hemoglobin (Hbr) (610 nm). A modified Beer‐Lambert calculation was used on two separate but similar seizures to approximate changes in Hbr, CBV as well as oxygenated hemoglobin (HbO2).
Results: Electrographically recorded seizures (n = 3) elicited a focal increase in both Hbr and CBV that lasted for the duration of the seizure, indicating that perfusion was inadequate to meet metabolic demand. Remarkably, these hemodynamic changes preceded the onset of the seizures by ∼20 s and occurred focally over the known location of the lesion and the seizure onsets.
Discussion: These findings demonstrate that the hemoglobin becomes deoxygenated in spite of large increase in CBV during spontaneous human focal seizures and that optically recorded hemodynamic events can be used both to predict and localize human focal epilepsy. Such data may someday be useful to assist in the presurgical evaluation of patients considered for epilepsy surgery and to predict the timing and location of seizure onsets.
EFFECT OF NITROGEN STARVATION ON OPTICAL PROPERTIES, PIGMENTS, AND ARACHIDONIC ACID CONTENT OF THE UNICELLULAR GREEN ALGA PARIETOCHLORIS INCISA (TREBOUXIOPHYCEAE, CHLOROPHYTA)1
Authors: Merzlyak Mark N. , Chivkunova Olga B. , Gorelova Olga A. , Reshetnikova Irina V. , Solovchenko Alexei E. , Khozin‐Goldberg Inna , Cohen Zvi 
Published: July 2007

Spectral properties of cell suspensions, individual cells, and extracts of the unicellular green alga Parietochloris incisa (Reisigl) Shin Watan. grown under low light were studied. Long‐term nitrogen (N) deprivation resulted in a decrease of chloroplast volume, appearance of numerous large cytoplasmic oil bodies, and the deposition of triacylglycerols with a high proportion of arachidonic acid. Chlorophylls a and b underwent a synchronous decline, whereas carotenoids (Car) showed a relative increase. Simultaneously, significant qualitative changes in the spectral properties of P. incisa individual cells, cell extracts, and cell suspensions were observed. To a large extent, the spectral changes observed in cell suspension could be attributed to a decrease in overall pigment content, leading to a gradual weakening of the so‐called package effect and accumulation of additional amounts of Car over chl, most probably, in oil bodies. Several optical characteristics of cell suspensions could serve as sensitive indicators of N‐deficiency in P. incisa. Furthermore, the absorption ratios, A476/A676 and A650/A676, showed close correlations with the Car‐to‐chl ratio and relative arachidonic acid (AA) content, respectively. The latter makes it possible to suggest that the increase in AA percentage in P. incisa proceeds in parallel with a decrease in cell chl content, accounting for the weakening of the package effect. N‐replenishment resulted in complete recovery of cell optical properties. The possible significance of the changes in cell ultrastructure, pigments, lipids, and optical properties is discussed with special reference to the ability of algae to adapt to and survive under conditions of long‐term nutrient deficiency.