bluuebunny/crossref_metadata_2025 huggingface dataset:
Shade Effects on Phaseolus vulgaris L. Intercropped with Zea mays L. under Well‐Watered Conditions
Authors: Tsubo M. , Walker S.
Published: May 2004

Field experiments were carried out under unstressed conditions of soil water during two summer crop growing seasons (1998–99 and 1999–2000 seasons) in a South African semi‐arid region (Bloemfontein, Free State, South Africa). The aim of this study was to investigate shade effects on beans intercropped with maize in terms of plant mass and radiation use. The experimental treatments were two cropping systems (no shading/sole cropping and shading/intercropping) and two row orientations (north–south and east–west). At the top of bean canopies shaded by maize, incident radiation was reduced by up to 90 %. Shading reduced total dry matter of beans by 67 % at the end of the growing season, resulting in yield losses. The dry matter partitioning into leaf and stem (the ratios of leaf and stem to total biomass) was about 50 % higher in intercropping than sole cropping. In contrast, intercropped beans had 40 % lower dry matter partitioning into pod (the ratio of pod to total biomass). Fraction of radiation intercepted by sole‐cropped beans steeply increased until canopy closure (0.9) and then slowly decreased, while fraction of radiation intercepted by intercropped beans remained constant between 0.0 and 0.2 throughout the growing seasons. However, intercropped beans had 77 % higher radiation use efficiency (RUE) than sole‐cropped beans. In contrast, for maize, no effect of intercropping (shading) was found on growth, partitioning, yield, radiation interception or RUE. Consequently, lower bean yield losses can be attained in association with late shading rather than early shading. This can be controlled by growing crops with different temporal and spatial treatments. As regards row treatment, no effect of row direction was found on growth, partitioning, yield, radiation interception or RUE.
Estimation of Leaf Area Index ofBeta vulgarisL. Based on Optical Remote Sensing Data
Authors: Hoffmann C. M. , Blomberg M.
Published: May 2004

Remote sensing and vegetation indices can be used to characterize the canopy of crops with a non‐destructive method on a large scale. Leaf area formation of sugar beet in early summer is the most important variable for crop growth models. This study aimed at estimating whether differences in leaf area development of sugar beet resulting from different agronomic practices can be determined with remote sensing. The relationship between the normalized difference vegetation index (NDVI) and leaf area index (LAI) during the season and yield of the storage root in autumn was studied in six field trials in 2001 and nine field trials in 2002. The vegetation index NDVI gave a good impression of differences in leaf development of sugar beet in early summer. LAI increased with increasing NDVI up to an NDVI of 0.65. Above that the NDVI did not respond as distinctly to treatments as the LAI. An exponential function was developed to calculate sugar beet LAI from NDVI, so that remote sensing data can be used as input variable for crop growth models. The yield of the storage root in autumn did not show any relationship to LAI or NDVI during the season, regardless of whether it was measured in June or September. Therefore, it seems to be necessary to combine NDVI data with crop growth models to forecast a potential sugar beet yield in autumn. For this purpose the formula presented is a valuable tool.
Treatment with intravenous hyperalimentation for severely anorectic patients and its outcome
Authors: TONOIKE TAKASHI , TAKAHASHI TOSHIHIKO , WATANABE HISASHI , KIMURA HIROYUKI , SUWA MAMI , AKAHORI KAORUKO , ITAKURA YOSHIKO
Published: May 2004

Abstract  In treating patients with severe anorexia nervosa, it is important to improve their physical condition first. Patients who had lost close to 60% standard bodyweight (SBW) were candidates for inpatient treatment due to the mortality risk. With 80% SBW as the target for therapy, they were given both intravenous hyperalimentation and food by oral intake in order to improve their physical condition. In total, 51 patients were admitted. One died and four patients dropped out in the course of treatment. Forty‐six patients who completed the inpatient treatment were reviewed. Although  admitted  with  an  average  weight  of  approximately  60% SBW,  they  were  discharged with a weight of approximately 80% SBW after approximately 60 days. An average follow up of 25.0 months was conducted, and two patients were found to have died. The mean weight, percentage resuming menstruation, and rehospitalization rate of the 44 survivors were 79% SBW, 23%, and 32%, respectively. The patients with the restricting type of anorexia had an earlier onset of the disorder and a better social outcome. Patients in whom onset occurred at a younger age had a better social outcome. After being discharged, the majority of the patients continued treatment as outpatients. Although the results were similar to those of conventional studies in terms of outcome, the shorter hospitalization was significant. Overall, in the treatment of patients with severe anorexia nervosa, it is important to begin psychotherapy while trying to improve their physical condition.
Trait and state aspects of harm avoidance and its implication for treatment in major depressive disorder, dysthymic disorder, and depressive personality disorder
Authors: ABRAMS KELLEY YOST , YUNE SOOK KYEONG , KIM SEOG JU , JEON HONG JIN , HAN SOO JUNG , HWANG JAEUK , SUNG YOUNG HOON , LEE KYUNG JIN , LYOO IN KYOON
Published: May 2004

Abstract  The authors evaluated the trait/state issues of harm avoidance in depressive‐spectrum disorders and its predictive potential for antidepressant response. Subjects with Diagnostic and Statistical Manual of Mental Disorders (4th edn; DSM‐IV) major depressive disorder (n = 39), dysthymic disorder (n = 37), depressive personality disorder (n = 39), and healthy control subjects (n = 40) were evaluated with the Temperament and Character Inventory and the 17‐item Hamilton Depression Rating Scale (HDRS‐17) at baseline and after a 12 week antidepressant treatment period. Higher harm avoidance scores predicted lesser improvement in subjects with dysthymic disorder and major depressive disorder, as determined by lesser decrease in HDRS‐17 scores. Mean harm avoidance scores in depressed subjects were consistently greater than those in healthy controls, controlling for age, gender and diagnosis. Mean harm avoidance scores decreased significantly in all depressive‐spectrum disorders after treatment, but still remained higher than harm avoidance scores in control subjects. The present study reports that harm avoidance is a reliable predictor of antidepressant treatment in subjects with major depressive disorder and dysthymic disorder and that harm avoidance is both trait‐ and state‐dependent in depressive‐spectrum disorders.
Intra‐episode hypomanic symptoms during major depression and their correlates
Authors: BENAZZI FRANCO
Published: May 2004

Abstract  Recent studies have shown that 40–50% of major depressive disorders (MDD) may become bipolar with time. Intra‐episode hypomanic symptoms in MDD may be a first step in this shift. The purpose of the present study was to find factors associated with intra‐episode hypomanic symptoms in MDD. Two hundred and forty‐three consecutive MDD outpatients were interviewed with the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (4th edn; DSM‐IV), Clinician Version (SCID‐CV), as modified by Benazzi and Akiskal (J. Affect. Disord. 2003; 73: 33–38). History of hypomania and presence of hypomanic symptoms during major depressive episode (MDE) were systematically assessed. Intra‐episode hypomanic symptoms were defined as an MDE combined with three or more hypomanic symptoms, following Akiskal and Benazzi (J. Affect. Disord. 2003; 73: 113–122). Major depressive disorder with intra‐episode hypomanic symptoms (MDD + H) was compared to MDD without hypomanic symptoms on classic bipolar validators. It was found that MDD + H (usually irritability, distractibility, racing thoughts, psychomotor agitation, and more talkativeness) was present in 32.5% of patients. Patients with MDD + H versus MDD had significantly lower age at onset, more atypical depressions, and more bipolar family history. Recurrences were not significantly different. Multivariate logistic regression found that bipolar family history and atypical depression were significantly and independently associated with MDD + H. Findings suggest that MDD + H may be associated with a bipolar vulnerability. Duration of illness and recurrences do not seem to be important for the onset of MDD + H. Bipolar genetic vulnerability seems to be required for onset of intra‐episode hypomanic symptoms in MDD. Intra‐episode hypomanic symptoms might be the first step of a process leading to the switch of MDD to bipolar disorders. Predicting the switch might have important treatment implications, because antidepressants used alone may worsen the course of bipolar disorders. Prospective studies are required to support these findings and hypotheses.
Quality of life and its correlates in patients with bipolar disorder stabilized on lithium prophylaxis
Authors: CHAND PRABHAT K. , MATTOO SURENDRA K. , SHARAN PRATAP
Published: May 2004

Abstract  The quality of life (QOL) of 50 bipolar disorder patients in remission (stabilized on lithium prophylaxis) was assessed and compared with that of clinically stable patients with schizophrenia (n = 20) and healthy subjects (n = 20). World Health Organization Quality of Life‐Bref (WHOQOL‐BREF) and Quality of Life Enjoyment and Satisfaction Questionnaire (Q‐LES‐Q) were used to assess QOL in the three groups of subjects. The factors that contribute or influence QOL (i.e. stressful life events, social support, daily hassles) were also studied using standardized instruments in the study group. It was found that, compared to schizophrenia group, the bipolar group had significantly better QOL in all the domains of Q‐LES‐Q and the domains of general well‐being, physical health and psychological health of the WHOQOL‐Bref. The bipolar group had similar QOL scores in all other domains and higher scores in leisure time activity domain of Q‐LES‐Q, in comparison to the healthy group. The QOL in the bipolar group was better in patients who were younger and had a lesser severity of daily hassle. The present findings suggest that euthymic patients with bipolar disorder have a QOL that is comparable to that of healthy subjects. In contrast, patients with clinically stable schizophrenia have a poorer QOL. Occurrence of daily hassles contributes significantly to QOL in patients with bipolar disorder. However, the relatively limited variance explained by the independent variables included in the study, suggests the need to examine other (perhaps non‐clinical) factors that may affect QOL.
Principles of antiepileptic drug treatment of epilepsy
Authors: YAMATOGI YASUKO
Published: May 2004

Abstract  For the successful treatment of epilepsy, accurate diagnosis of epilepsy and epileptic seizures, and proper selection of antiepileptic drugs (AED) according to the classification of epileptic syndromes are fundamentally important. Efficacy of AED treatment, however, depends not only on its pharmacological action but also on its efficient use, namely a rationally thinking tailor‐made treatment considering the characteristics of each patients, i.e. individual differences in pharmacokinetics, factors influencing AED concentrations, AED interactions, and comprehensively their life style and psychosocial factors.
Therapy‐resistant epilepsy in children: With the view of the long‐term outcome
Authors: MORIKAWA TATEKI
Published: May 2004

Abstract  Of 362 children with therapy‐resistant epilepsy, 119 patients had generalized tonic seizures, which were the most common seizure type in patients with generalized epilepsy. The long‐term observation of the patients with tonic seizures revealed that their seizures were completely controlled in 27 patients for more than 5 years. The effective antiepileptic drugs were VPA (10 patients), PHT (5), CLB (4), ZNS (2), VPA + PHT (4), ZNS + CLB (1) and VPA + AZA (1). For obtaining improvement of tonic seizures, another strong factor is reducing the number of antiepileptic drugs, such as the average number of drugs, which was 4.7 to 2.4 in these 27 patients.
Etiologic factors and clinical features of symptomatic epilepsy: Focus on pediatric cases
Authors: FUJIWARA TATEKI , SHIGEMATSU HIDEO
Published: May 2004

Abstract  We discuss the presumptive etiologic factors of symptomatic epilepsy from the clinical standpoint, based on our experience of 383 inpatients with epilepsy, with a focus on children. The main (top three) presumptive etiologic factors in partial epilepsy are intracranial infection, cerebral malformation and perinatal brain damage. In generalized epilepsy, the main presumptive etiologic factors are perinatal brain damage, intracranial infection, and cerebral malformation. As regards presumptive etiologic factors in partial epilepsy, cerebral malformation was most common in frontal lobe epilepsy, initial convulsive status in temporal lobe epilepsy and perinatal brain damage in occipital lobe epilepsy. Electroclinical characteristics of severe myoclonic epilepsy in infancy, the most intractable epilepsy syndrome in infancy, is the focus and recent advances of genetic research are introduced.
Neuroimaging and presurgical evaluation of symptomatic epilepsies
Authors: OTSUKI TAISUKE
Published: May 2004

Abstract  The goal of presurgical evaluation of intractable epilepsy is to identify epileptogenic regions in the brain. From our experience of 38 cases of resective epilepsy surgery from the last 3 years, ictal SPECT was considered the most sensitive at detecting focal changes relating to seizures compared to other neuroimaging modalities, such as MRI, FDG‐PET, SPECT and MEG. At interictal state, on the other hand, FDG‐PET was most sensitive, especially in cases with focal cortical dysplasia, which is often MRI‐invisible. In dysplastic tumors, MRI showed the highest concordance rate to clinically verified epileptogenic regions. Activation studies using functional neuroimaging such as PET and fMRI is useful to evaluate brain functions at epileptogenic regions presurgically. The role of functional brain imaging in epilepsy surgery is considered to be: (i) case selection for resective surgery, (ii) case selection for invasive EEG monitoring, and (iii) navigation of electrode placement and cortical resection.
Preoperative mapping for patients with supplementary motor area epilepsy: multimodality brain mapping
Authors: YAMANE FUMITAKA , MURAGAKI YOSHIHIRO , MARUYAMA TAKASHI , OKADA YOSHIKAZU , ISEKI HIROSHI , IKEDA AKIO , HOMMA IKUO , HORI TOMOKATSU
Published: May 2004

Abstract  Surgical management and strategies for the supplementary motor area (SMA) epilepsy are described. The following is our preoperative evaluations. The steps include functional magnetic resonance imaging (fMRI), interictal dipole tracing (DT), subdural electrodes mapping, measurements of movement‐related cortical potential (MRCP), and the use of the intraoperative open MRI under conscious craniotomy. Six patients with SMA epilepsy underwent surgery after the mapping procedures and are now seizure‐free. Combinations of preoperative (fMRI, subdural electrodes mapping) and intraoperative mapping allow exact localization and identification of the critical functional areas. Early postoperative deficits in motor and speech function were profound but patients recovered rapidly. It is concluded that the step of mapping procedures plays an important role in the management of SMA epilepsy surgery.
Clinical and experimental studies of epilepsy associated with focal cortical dysplasia
Authors: HASHIZUME KIYOTAKA , TSUDA HIROSHIGE , HODOZUKA AKIRA , TANAKA TATSUYA
Published: May 2004

Abstract  The results of clinical and experimental studies on epilepsy associated with focal cortical dysplasia (FCD) are presented. We have been interested in the findings of abnormal increases in the numbers of small vessels in specimens of FCD resected from epilepsy patients. In the clinical study of 13 patients with epilepsy, specimens of FCD or dysembryoplastic neuroepithelial tumor (DNT) were examined using immunohistochemistry. The number of vessels in both lesions were greater than those in cortical specimens of autopsy cases without epilepsy. Because the vessels showed negative staining of VEGF, it was thought that the phenomenon of increase in the number of vessels was simply a hypervascularity, not a neovascularity. The local hypervascularity was expected to show local hyperperfusion in CBF‐SPECT study, but interictal SPECT demonstrated local hypoperfusion and ictal SPECT showed hyperperfusion. This may have been caused by a functional change in those vessels. In the experimental study, we tried to make a new animal model of FCD to study epileptogenicity of FCD. When kainic acid had been infused into the neocortex in the neonatal rats, FCD was induced in adult Wistar rats. Histopathological examination revealed cortical dyslamination and abnormal neurons. On EEG, local spike bursts were elicited from the lesions, however, clinical seizures were not detected. Although the data are preliminary and observation over a longer period is required to determine whether spontaneous seizures will occur in this model, it is expected that this new model will be useful for studying epilepsy associated with FCD.
Questioning the effectiveness of the Natura 2000 Special Areas of Conservation strategy: the case of Crete
Authors: Dimitrakopoulos Panayiotis G. , Memtsas Dimitris , Troumbis Andreas Y.
Published: May 2004

Aim This study examines the effectiveness of the selected ‘network’ of Natura 2000 Special Areas of Conservation (SACs) at a regional scale in Greece, in terms of its representativeness of plant biodiversity.

Location The island of Crete is used as a case study because it is considered to be one of the 10 hotspots for biodiversity in the Mediterranean Basin.

Methods Hotspot analysis and complementarity algorithms are used to define priority areas for conservation and calculate their spatial overlap with the Natura 2000 SACs in Crete.

Results The various categories of hotspots contain subsamples of plant categories, used for their definition. Spatial overlap among different categories of hotspots, areas of complementary diversity and Natura 2000 SCAs is low.

Main conclusions The results show that the Natura 2000 SACs ‘network’ in Crete seems insufficient to ensure satisfactory representation of the regional plant biodiversity elements.
Contingent effects of water balance variation on tree cover density in semiarid woodlands
Authors: Kerkhoff Andrew J. , Martens Scott N. , Shore Gregory A. , Milne Bruce T.
Published: May 2004

Aim  The local distribution of woody vegetation affects most functional aspects of semiarid landscapes, from soil erosion to nutrient cycling. With growing concern about anthropogenic climate change, it has become critical to understand the ecological determinants of woody plant distribution in semiarid landscapes. However, relatively little work has examined the determinants of local variation in woody cover. Here we examine water balance controls associated with patterns of tree cover density in a topographically complex semiarid woodland.

Location  Los Pinos Mountains, Sevilleta National Wildlife Refuge LTER, New Mexico, USA.

Methods  To explore the relationship between local water balance variation and tree cover density, we used a combination of high‐resolution (1 × 1 m), remotely sensed imagery and quantitative estimates of water balance variation in space and time. Regression tree analysis (RTA) was used to identify the environmental parameters that best predict variation in tree cover density.

Results  Using six predictor variables, the RTA explains 39% of the deviance in tree cover density over the landscape. The relationship between water balance conditions and tree cover density is highly contingent; that is, similar tree cover densities occur under very different combinations of water balance parameters. Thus, the effect of one environmental parameter on tree cover density depends on the values of other parameters. After tree cover density is adjusted for water balance conditions, residual variation is related to tree cover density in the neighbourhood of a particular location.

Conclusion  In semiarid landscapes, vegetation structure is largely controlled by water supply and demand. Results presented here indicate that localized feedbacks and site‐specific historical processes are critical for understanding the responses of semiarid vegetation to climate change.
Use of a latitudinal gradient in bald cypress (Taxodium distichum) production to examine physiological controls of biotic boundaries and potential responses to environmental change
Authors: Middleton Beth A. , McKee Karen L.
Published: May 2004

Aim  Predictions of vegetation change with global warming require models that accurately reflect physiological processes underlying growth limitations and species distributions. However, information about environmental controls on physiology and consequent effects on species boundaries and ecosystem functions such as production is limited, especially for forested wetlands that are potentially important carbon sinks.

Location  The bald cypress (Taxodium distichum) region of the south‐eastern United States was studied to examine how production of an important forested wetland varies with latitude and temperature as well as local hydrology.

Methods  We used published data to analyse litter production across a latitudinal gradient from 26.2 to 37.8° N to determine how bald cypress swamps might respond to alternate climate conditions and what changes might occur throughout the distributional range.

Results  Litterfall rates followed a bell shaped curve, indicating that production was more limited at the distributional boundaries (c. 225 g/m2 year−1) compared to the mid‐range (795–1126 g/m2 year−1). This pattern suggests that conditions are suboptimal near both boundaries and that the absence of populations outside this latitudinal range may be largely due to physiological constraints on the carbon balance of dominant species. While dispersal limitations cannot be totally discounted, competition with other wetland types at the extremes of the range does not seem likely to be important because the relative basal area of bald cypress does not decrease near the edges of the range. Impaired hydrology depressed production across the entire range, but more in the south than the north.

Main conclusions  Our findings suggest that (1) physiological limitations constrain biotic boundaries of bald cypress swamps; (2) future changes in global temperature would affect litter production in a nonlinear manner across the distributional range; (3) local changes in hydrology may interact with climate to further reduce litter production, particularly at lower latitudes; and (4) southernmost forests could be extirpated if environmental conditions compromise carbon balance and water‐use efficiency of trees.
Growth of Lythrum salicaria and Phragmites australis plants originating from a wide geographical area: response to nutrient and water supply
Authors: Bastlová Daša , Čížková Hana , Bastl Marek , Květ Jan
Published: May 2004

Aim  The response of L. salicaria and P. australis plants originating from a broad latitudinal gradient to mineral nutrient and water supply was studied. We suggest implications for mechanisms possibly underlying the invasiveness of these two plant species.

Location  A common garden tub experiment was carried out at Třeboň, Czech Republic (49° N 14°47′ E, altitude 433 m).

Methods  Plants of 30 L. salicaria and 6 P. australis populations originating from a wide geographical area in Europe and in Israel (60°−32° N latitude, 6° W−20° E longitude) were cultivated for one growing season at two water levels and three (L. salicaria) or two (P. australis) nutrient doses, respectively. At the end of cultivation, basic morphological and growth characteristics were recorded.

Results  The latitude of the original geographical location was the most significant factor, affecting both the phenology and most of the plant morphological and growth characteristics measured in both plant species, with the characteristics related to plant size being negatively correlated with latitude. The effect of nutrient dose was very strong in both species, while the effect of water level was more pronounced in P. australis than in L. salicaria.

Main conclusions  The results confirmed the existence of a large phenotypic variability in both plant species within their native ranges of occurrence. In both plant species, the latitudinal variation in plant morphological and growth characteristics most probably indicates the differentiation of genotypes adapted to local geographical conditions. The plants of both species originating from all geographical locations tested responded to the respective nutrient treatments in a similar manner. Exceptions were found in growth characteristics related to reproduction in L. salicaria, indicating that better nutrient supply could enhance the reproductive ability of certain genotypes. Based on the results obtained, we suggest implications for mechanisms possibly underlying the invasiveness of the plant species studied.
Defining Interests: Disambiguation and the Need for New Distinctions?
Authors: Jordan Grant , Halpin Darren , Maloney William
Published: May 2004

This article notes the systemic lack of conceptual clarity in the social sciences and attempts to illustrate the adverse consequences by closer examination of the particular example of the interest group field. It indicates the significant ambiguities implicit in the term. Not all policy-influencing organisations are interest groups as normally understood, but because there is a lack of an appropriate label the term interest group is used by default. The article seeks to distinguish between interest groups and other policy relevant bodies—often corporations or institutions. It finds disadvantages in adopting a functional interpretation of the interest group term (i.e. any organisation trying to influence public policy). While the wider range of organisations are crucial in understanding the making of public policy, it is confusing to assume that this wider population are all interest groups. The article instead advances the complementary notions of pressure participant, policy participant and interest group. This slightly expanded repertoire of terms avoids conflating important distinctions, and, in Sartori's term permits ‘disambiguation’. The core assumption is that the search for comparative data and exploration of normative questions implies some harmonisation in the interest group currency.
Internal and external motivation in phonetic change: Dialect levelling outcomes for an English vowel shift
Authors: Torgersen Eivind , Kerswill Paul
Published: May 2004

This article is a contribution to the debate about the primacy of internal versus external factors in language change (Farrar and Jones 2002; Thomason and Kaufman 1988). Taking Labov's Principles of Vowel Shifting (Labov 1994) as representing internal factors, we examine a vowel shift in Ashford, south‐east of London. F1 and F2 measurements of the short vowels suggest a classic chain shift, largely following Labov's Principles II and III (though Labov's assumption that London short front vowels are rising is shown to be wrong). However, corresponding data from Reading, west of London, evidence no signs of a chain shift. The two datasets show identical targets for the changes in each town. Thus, there has been convergence between the two short vowel systems – from different starting points. We argue that a dialect contact model is more explanatory than internal factors in  this case of regional dialect levelling in the south‐east of England.
Aggregation of random parameters Ornstein‐Uhlenbeck or AR processes: some convergence results
Authors: Oppenheim Georges , Viano Marie‐Claude
Published: May 2004

Abstract.  It is shown that by aggregating simple random parameters, processes such as autoregressive micro‐relationships or Ornstein‐Uhlenbeck processes, one can obtain various seasonal long memory Gaussian models. The investigation concerns the discrete as well as the continuous time setting. In both situations the precise asymptotic behaviour of the covariance is studied. The regularity of sample paths is evaluated when possible.
A Note on the Filtering for Some Time Series Models
Authors: Peiris S. , Thavaneswaran A.
Published: May 2004

Abstract. This paper is concerned with filtering for various types of time series models including the class of generalized ARCH models and stochastic volatility models. We extend the results of Thavaneswaran and Abraham (1988) for some time series models using martingale estimating functions. Nonlinear filtering for biostatistical time series models with censored observations is also discussed as a special case.
An account of the joint fight for human rights by Flemish Musketeers and their Tinker Ladies
Authors: Roets Griet , Van de Perre Danny , Hove Geert Van , Schoeters Ludo , Schauwer Elisabeth De
Published: May 2004

The Musketeer book One for All – All for One! A joint fight for human rights (Onze Nieuwe Toekomst 2002) is a disclosure of oral accounts of people with the label of ‘learning difficulties’. The Musketeer book is particularly an articulation of their individual and collective politics of resistance. With this collection of stories – taken from life – true activists and their allies hope to bring tangible shifts in beliefs and attitudes in disabling society. In this paper, the Head Musketeer Danny and his right‐hand Musketeer Ludo reflect upon their relational perspective on the process of (self‐)empowerment with their Tinker Ladies. Our experience unfolds like walking a high wire. Our Flemish perspective reveals a profound awareness of power dynamics in an intensely felt cooperative research process.
Sociocultural study of intellectual disability: moving beyond labelling and social constructionist perspectives
Authors: Klotz Jani
Published: May 2004

This paper outlines the development of the sociocultural study of people with an intellectual disability, focusing in particular on the pioneering work of Robert Edgerton, Robert Bogdan and Steven Taylor, David Goode and John Gleason.1 As part of this analysis, I shall critically assess the contributions and limitations of these authors. I argue that the parameters of the debate have tended to become too rigid. The sociocultural study of intellectual disability has mostly focused on the experiences of people with mild intellectual disabilities, extrapolating from these experiences conclusions about the nature of intellectual disability in general, while the experiences and life worlds of those whose impairments are severe, profound, and often multiple, are often ignored. However, the portrayal and analysis of such people's lives are essential for our greater understanding and appreciation of intellectual disability, and of human difference in all its diverse manifestations. It is also essential for understanding, accepting and respecting people with severe and profound intellectual disabilities, and recognizing that such people are already living socially meaningfully lives as they are, despite not conforming to the dominant and socially prescribed norms and expectations of meaningful action and behaviour.2 The methodological and theoretical tools that are required to engage with and interpret such lives, however, are profoundly different to those used by the majority of sociocultural theorists in the field, as shall be discussed below.
Mutations in the extracellular domains of glutamate‐gated chloride channel α3 and β subunits from ivermectin‐resistant Cooperia oncophora affect agonist sensitivity
Authors: Njue Annete I. , Hayashi Jon , Kinne Lyle , Feng Xiao‐Peng , Prichard Roger K.
Published: May 2004

Two full‐length glutamate‐gated chloride channel (GluCl) cDNAs, encoding GluClα3 and GluClβ subunits, were cloned from ivermectin‐susceptible (IVS) and ‐resistant (IVR) Cooperia oncophora adult worms. The IVS and IVR GluClα3 subunits differ at three amino acid positions, while the IVS and IVR GluClβ subunits differ at two amino acid positions. The aim of this study was to determine whether mutations in the IVR subunits affect agonist sensitivity. The subunits were expressed singly and in combination in Xenopus laevis oocytes. Electrophysiological whole‐cell voltage‐clamp recordings showed that mutations in the IVR GluClα3 caused a modest but significant threefold loss of sensitivity to glutamate, the natural ligand for GluCl receptors. As well, a significant decrease in sensitivity to the anthelmintics ivermectin and moxidectin was observed in the IVR GluClα3 receptor. Mutations in the IVR GluClβ subunit abolished glutamate sensitivity. Co‐expressing the IVS GluClα3 and GluClβ subunits resulted in heteromeric channels that were more sensitive to glutamate than the respective homomeric channels, demonstrating co‐assembly of the subunits. In contrast, the heteromeric IVR channels were less sensitive to glutamate than the homomeric IVR GluClα3 channels. The heteromeric IVS channels were significantly more sensitive to glutamate than the heteromeric IVR channels. Of the three amino acids distinguishing the IVS and IVR GluClα3 subunits, only one of them, L256F, accounted for the differences in response between the IVS and IVR GluClα3 homomeric channels.
Multiple sites of ethanol action in α1 and α2 glycine receptors suggested by sensitivity to pressure antagonism
Authors: Davies Daryl L. , Crawford Daniel K. , Trudell James R. , Mihic S. John , Alkana Ronald L.
Published: May 2004

The current study used an ethanol antagonist, increased atmospheric pressure, to test the hypothesis that ethanol acts on multiple sites in glycine receptors (GlyRs). The effects of 12 times normal atmospheric pressure of helium‐oxygen gas (pressure) on ethanol‐induced potentiation of GlyR function in Xenopus oocytes expressing human α1, α2 or the mutant α1(A52S) GlyRs were measured using two‐electrode voltage clamp. Pressure reversibly antagonized potentiation of glycine in α1 GlyR by 40–200 mm ethanol, but did not antagonize 10 and 25 mm ethanol in the same oocytes. In contrast, pressure did not significantly affect potentiation of glycine by 25–100 mm ethanol in α2 GlyRs, nor did pressure alter ethanol response in the A52S mutant. Pressure did not affect baseline receptor function or response to glycine in the absence of ethanol. These findings provide the first direct evidence for multiple sites of ethanol action in GlyRs. The sites can be differentiated on the basis of ethanol concentration, subunit and structural composition and sensitivities to pressure antagonism of ethanol. Parallel studies with butanol support this conclusion. The mutant α1(A52S) GlyR findings suggest that increased attention should be focused on the amino terminus as a potential target for ethanol action.
Neisseria meningitidis‐induced death of cerebrovascular endothelium: mechanisms triggering transcriptional activation of inducible nitric oxide synthase
Authors: Constantin Despina , Cordenier Axelle , Robinson Karen , Ala'Aldeen Dlawer A. A. , Murphy Sean
Published: May 2004

The intense host response to meningococcus reflects marked functional and morphological alterations in blood–brain barriers. We showed previously that mouse‐derived cerebrovascular endothelium responded to meningococcal lysates with a robust nitric oxide (NO) response, resulting in the loss of cell viability. To understand how the NO synthase‐2 gene in endothelium is activated by meningococcus, we investigated upstream roles for specific protein kinases. Using known kinase inhibitors, and measuring both mRNA expression and nitrite release, we found MAPK/ERK kinase (MEK)2, p38 kinase and phosphoinositide 3‐kinase (but not MEK1 or phospholipase C) to be implicated in the NO synthase‐2 response. Recruitment of these kinases by meningococcus did not depend on the prior release of the proinflammatory cytokines tumour necrosis factor α or interleukin‐1β from endothelium. These endothelial cells were found to express toll‐like receptors (TLR) 2, 4 and 9 and antibodies directed against TLR 2 and 4 (but not TLR 9) blocked the NO synthase‐2 response to meningococcus. Both meningococcus‐induced translocation of nuclear factor‐kB (NF‐kB) and endothelial cell death were blocked by a known inhibitor of p38 kinase. Calpain inhibitor‐1 blocked the NO synthase‐2 response to meningococcus, which is further evidence of a role for NF‐kB.
Stress‐induced activation of the immediate early gene Arc (activity‐regulated cytoskeleton‐associated protein) is restricted to telencephalic areas in the rat brain: relationship to c‐fos mRNA
Authors: Ons Sheila , Martí Octavi , Armario Antonio
Published: May 2004

Arc is an effector immediate early gene whose expression is induced in situations of increased neuronal activity. However, there is no report on the influence of stress on Arc expression. Here, we compared the induction of both c‐fos and Arc mRNAs in the brain of rats exposed to one of three different stressful situations: novel environment, forced swimming and immobilization. An absent or weak c‐fos mRNA signal was observed in control rats, whereas those exposed to one of three stressors showed enhanced c‐fos expression in a wide range of brain areas. Constitutive Arc expression was observed in some areas such as cortex, striatum, hippocampus, reticular thalamic nucleus and cerebellar cortex. In response to stressors, a strong induction of Arc was observed, but the pattern was different from that of c‐fos. For instance, activation of Arc but not c‐fos was observed in the nucleus accumbens after immobilization and in the hippocampus after novel environment. No Arc induction was observed in diencephalic and brainstem areas. The present data show that Arc has a neuroanatomically restricted pattern of induction in the brain after emotional stress. Telencephalic activation suggests that a more intense induction of synaptic plasticity is occurring in this area after exposure to emotional stressors.
3‐Nitropropionic acid‐induced neurotoxicity – assessed by ultra high resolution positron emission tomography with comparison to magnetic resonance spectroscopy
Authors: Brownell Anna‐Liisa , Chen Y. Iris , Yu Meixiang , Wang Xukui , Dedeoglu Alpaslan , Cicchetti Francesca , Jenkins Bruce G. , Beal M. Flint
Published: May 2004

To explore acute and long‐term effects of 3‐nitropropionic acid (3‐NP)‐induced neurotoxicity, longitudinal positron emission tomography (PET) studies of energy metabolism and magnetic resonance spectroscopic (MRS) studies of neurochemicals were conducted in a rat model. The first injection of 3‐NP (20 mg/kg i.p.) was followed by MRS study of neurochemicals and PET study of glucose utilization using [18F]2‐fluorodeoxy‐d‐glucose (18F‐FDG). After that, 3‐NP administration was done two times a day with a dose of 10 mg/kg i.p. until animals were symptomatic or for a maximum of 5 days combined with daily PET studies. Long‐term effects were investigated 4 weeks and 4 months after cessation of 3‐NP. These studies showed a significant inter‐animal variation in response of 3‐NP toxicity. Animals that developed large striatal lesions had decreased glucose utilization in the striatum and cortex 1 day after starting 3‐NP injections. Similarly succinate and lactate/macromolecule levels were enhanced; these changes being, however, reversible. Progressive degeneration was observed by decreasing striatal glucose utilization and N‐acetylaspartate (NAA) and increasing choline. These observations paralleled with weight loss and deficits in behavior. Animals that did not develop lesions showed reversible enhancement in cortical glucose utilization and no change in striatal glucose utilization or neurochemicals or locomotor activity.
Taurine‐induced long‐lasting potentiation in the rat hippocampus shows a partial dissociation from total hippocampal taurine content and independence from activation of known taurine transporters
Authors: Dominy John , Thinschmidt Jeffrey S. , Peris Joanna , Dawson Ralph , Papke Roger L.
Published: May 2004

Perfusion with high millimolar levels of taurine evoked a long‐lasting potentiation (LLP‐TAU) of synaptic transmission in the Schaffer‐collateral CA1 region of the rat hippocampus. Although LLP‐TAU showed some correlations to increases in the total taurine content of hippocampal slices, it could not be blocked by the taurine transport inhibitor guanidinoethanesulfonic acid (GES), which was able to significantly reduce total slice taurine uptake. Inhibition of GABA transport by either nipecotic acid or β‐guanidinopropionate failed to abolish LLP‐TAU and had no significant effect on taurine uptake. The combination of GES and nipecotic acid also had no significant effect on LLP‐TAU. Experiments with transportable structural analogs of taurine (β‐aminoisobutyric acid, homotaurine, and isethionic acid) suggest that activation of classical taurine transport pathways does not always yield a robust LLP‐TAU. Hippocampal LLP‐TAU could be significantly attenuated, however, by pre‐incubation with submillimolar levels of taurine. In summary, the development of LLP‐TAU in the rat hippocampus appears to be associated with the intracellular accumulation rather than the activation of known transporters of taurine, but the precise means of its accumulation remains to be identified.
Regulation of glycogen synthase kinase‐3β by products of lipid peroxidation in human neuroblastoma cells
Authors: Dozza Barbara , Smith Mark A. , Perry George , Tabaton Massimo , Strocchi Paola
Published: May 2004

The potential role of 4‐hydroxynonenal (HNE), a major product of membrane lipid peroxidation, in regulating glycogen synthase kinase‐3β (GSK3β) activity was examined in human neuroblastoma IMR‐32 cells. The inhibition of GSK3β activity by HNE was observed by in vitro kinase assays with two substrates, the synthetic glycogen synthase peptide‐2 and the human recombinant tau. GSK3β activity is regulated by Ser9 (inhibitory) and Tyr216 (stimulatory) phosphorylation. By using specific activity‐dependent phospho‐antibodies, immunoblot analysis revealed that HNE induces an increase in phosphorylation of GSK3β in Ser9, enhancing basal phosphatidylinositol 3‐kinase (PI3K)/AKT and extracellular signal‐regulated kinase 2 (ERK2) signalling pathways. Ser9‐GSK3β phosphorylation induced by HNE was abolished by treatment with LY294002 or U0126, two inhibitors of PI3K/AKT and ERK pathways, respectively. These experiments provide evidence for a crucial role of the PI3K/AKT and ERK2 pathways as intracellular targets of HNE that mediate the inhibition of GSK3β activity in regulating cellular response to HNE in viable cells under conditions in which membrane lipid peroxidation occurs. These data support a key role for GSK3β as a mediator of the signalling pathways activated by oxidative stress, and therefore it may be included among the redox‐sensitive enzymes.
Pro‐regenerative properties of cytokine‐activated astrocytes
Authors: Liberto Christina M. , Albrecht P. J. , Herx L. M. , Yong V. W. , Levison S. W.
Published: May 2004

The prevailing view of the astrocytic response to injury is that reactive astrocytes impede the regenerative process by forming scar tissue. As the levels of many cytokines dramatically increase following CNS insult and as this increase in cytokine expression precedes the production of the glial scar, a long‐standing view has been that cytokines diminish neuronal survival and regeneration by stimulating the formation of astrogliotic scar tissue. However, there is a wealth of data indicating that cytokines ‘activate’ astrocytes, and that cytokine‐stimulated astrocytes can promote the recovery of CNS function. Supporting evidence demonstrates that cytokine‐activated astrocytes produce energy substrates and trophic factors for neurons and oligodendrocytes, act as free radical and excess glutamate scavengers, actively restore the blood–brain barrier, promote neovascularization, restore CNS ionic homeostasis, promote remyelination and also stimulate neurogenesis from neural stem cells. Accordingly, a re‐assessment of cytokine‐activated astrocytes is necessary. Here, we review studies that promote the thesis that cytokines elicit potent neuroprotective and regenerative responses from astrocytes.
A low molecular weight copper chelator crosses the blood–brain barrier and attenuates experimental autoimmune encephalomyelitis
Authors: Offen Daniel , Gilgun‐Sherki Yossi , Barhum Yael , Benhar Moran , Grinberg Leonid , Reich Reuven , Melamed Eldad , Atlas Daphne
Published: May 2004

Increasing evidence suggests that enhanced production of reactive oxygen species (ROS) activates the MAP kinases, c‐Jun N‐terminal protein kinase (JNK) and mitogen‐activated protein kinase MAPK (p38). These phosphorylated intermediates at the stress‐activated pathway induce expression of matrix metalloproteinases (MMPs), leading to inflammatory responses and pathological damages involved in the etiology of multiple sclerosis (MS). Here we report that N‐acetylcysteine amide (AD4) crosses the blood–brain barrier (BBB), chelates Cu2+, which catalyzes free radical formation, and prevents ROS‐induced activation of JNK, p38 and MMP‐9. In the myelin oligodendrocyte glycoprotein (MOG)‐induced experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, oral administration of AD4 drastically reduced the clinical signs, inflammation, MMP‐9 activity, and protected axons from demylination damages. In agreement with the in vitro studies, we propose that ROS scavenging by AD4 in MOG‐treated animals prevented MMP's induction and subsequent damages through inhibition of MAPK pathway. The low toxicity of AD4 coupled with BBB penetration makes this compound an excellent potential candidate for the therapy of MS and other neurodegenerative disorders.
Delayed genomic responses to transient middle cerebral artery occlusion in the rat
Authors: Kim Jung‐Bin , Piao Chun‐Shu , Lee Kang Woo , Han Pyung‐Lim , Ahn Joon Ik , Lee Yong Sung , Lee Ja‐Kyeong
Published: May 2004

Ischemic stress in the brain induces acute and massive neuronal death in the targeted area, which is followed by a second round of detrimental processes, called delayed neuronal death, in the neighboring areas. To test the hypothesis that transcriptional control plays a role in the pathophysiology of the postischemic brain, the genomic responses that occurred in the brain at 3, 6 and, 12 h, and 1, 2 or 4 days after transient middle cerebral artery occlusion (MCAO) were examined using a microarray harboring 5000 rat cDNAs. This analysis indicated that the number of up‐regulated genes was gradually increased, along with the concomitant reduction in the number of down‐regulated genes, until 12 h to 1 day after MCAO. It was followed by a delayed surge of down‐regulated genes at 2 days after MCAO. Northern blots and immunohistological analysis confirmed the validity of these microarray data. We present a list of 85 genes that were up‐regulated more than 2.3‐fold between 12 h and 4 days after MCAO, which included 56 novel genes whose expression has not previously been implicated in ischemic pathophysiology. The list included genes involved in oxidative stress, inflammation, extracellular matrix (ECM), neuronal development and differentiation processes. Together these results suggest that the pathophysiology of the postischemic brain proceeds by the transcriptional activation of genes related to the process of delayed neuronal damage and/or recovery and repair.