bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatigue in Chronic Migraine Patients
Authors: Peres MFP , Zukerman E , Young WB , Silberstein SD
Published: March 2003

Fatigue is a common symptom frequently reported in many disorders including headaches, but little is known about its nature. The objective was to determine the prevalence of fatigue in chronic migraine (CM) patients, to define its subtypes and its relationship with other conditions comorbid with CM. Sixty-three CM patients were analysed. The Fatigue Severity Scale (FSS), the Chalder fatigue scale and the CDC diagnostic criteria for chronic fatigue syndrome (CFS) were used. Fifty-three (84.1%) patients had FSS scores greater than 27. Forty-two (66.7%) patients met the CDC criteria for CFS. Thirty-two patients (50.8%) met the modified CDC criteria (without headache). Beck depression scores correlated with FSS, mental and physical fatigue scores. Trait anxiety scores also correlated with fatigue scales. Women had higher FSS scores than men, P < 0.05. Physical fatigue was associated with fibromyalgia, P < 0.05. Fatigue as a symptom and CFS as a disorder are both common in CM patients. Therapeutic interventions include a graded aerobic exercise program, cognitive behavioural therapy and antidepressants. Identification of fatigue and its subtypes in headache disorders and recognition of headaches in CFS patients has implications for the pathophysiology, diagnosis and treatment of these disorders.
What is the Evolutionary Advantage of Migraine?
Authors: Loder E
Published: March 2003

Susceptibility to migraine is determined by genetic factors and is therefore subject to the forces of natural selection. Migraine is a common and ancient disorder whose prevalence may be increasing, suggesting that a migraine-prone nervous system may be associated with reproductive or survival advantages. Five evolutionary explanations are reviewed that might account for the persistence of migraine: (i) migraine as a defence mechanism; (ii) migraine as a result of conflict with other organisms; (iii) migraine as result of novel environmental factors; (iv) migraine as a trade-off between genetic harms and benefits; and (v) migraine as a design constraint. An evolutionary perspective on migraine allows the generation of important hypotheses about the disorder and suggests rewarding possibilities for further research.
Health-Related Quality of Life in Patients with Cluster Headache During Active Periods
Authors: D'Amico D , Rigamonti A , Solari A , Leone M , Usai S , Grazzi L , Bussone G
Published: March 2003

Cluster headache is characterized by excruciatingly painful headaches which occur one or several times during the day. Little is known about the functional consequences of this severe headache form. We assessed health-related quality of life in 56 consecutive patients, 34 of whom were episodic cluster headache patients during an active period, and 22 had chronic cluster headache. All patients completed the Short Form-36 (SF-36). We found lower scores in the studied patients than in those reported in the general population for all SF-36 domains. For most scales the difference was significant ( P < 0.0001, Student's t-test, Bonferroni correction). Our findings suggest that cluster headache has marked functional consequences even when appropriate treatments are used.
Sleep Apnoea and Chronic Headache
Authors: Sand T , Hagen K , Schrader H
Published: March 2003

The objective of this study was to estimate prevalence of headache and body pain among patients referred for suspected sleep apnoea syndrome compared with the occurrence in a large population-based study (the Nord-Tr⊘ndelag Health Study). Between 1995 and 1998, ambulatory polysomnography was successfully performed in 421 consecutive patients, 324 of whom completed a questionnaire about sleep-related habits, headache and body pain. Headache and neck pain were more likely among patients admitted for polysomnography compared with the general population ( n = 41 340). In the multivariate analyses, this association was mainly restricted to those with frequent complaints (≥7 days per month). Chronic headache (headache ≥ 15 days per month) was seven times more common among individuals with and without confirmed obstructive sleep apnoea syndrome than in the general population. There was no linear dose-response relationship between headache and neck pain and severity of apnoea or oxygen desaturation. Thus, hypoxia per se is less likely to explain the high headache prevalence among patients admitted for polysomnography.
Neurogenic Dural Protein Extravasation Induced by Meta-Chlorophenylpiperazine (Mcpp) Involves Nitric Oxide and 5-HT2B Receptor Activation
Authors: Johnson KW , Nelson DL , Dieckman DK , Wainscott DB , Lucaites VL , Audia JE , Owton WM , Phebus LA
Published: March 2003

The compound m-chlorophenylpiperazine (mCPP), which is known to trigger migraine-like head pain in some subjects, was evaluated for its ability to induce dural plasma protein extravasation (PPE) in guinea pigs. Intravenous mCPP dose-dependently increased PPE. This effect was inhibited by non-selective 5-HT2 receptor antagonists (methysergide, LY53857, LY215840), by a peripherally restricted 5-HT2 receptor antagonist (xylamidine) and by a 5-HT2B selective receptor antagonist (LY202146). These data suggests that peripheral 5-HT2B receptors mediate mCPP-induced PPE. The nitric oxide synthase inhibitor L-NAME and 5-HT1 agonist sumatriptan also blocked mCPP-induced PPE, suggesting a role for nitric oxide (NO) and the trigeminal system, respectively. NO release has been linked to activation of the 5-HT2B receptor on the vascular endothelium. However, LY202146 did not block PPE induced by electrical stimulation of the trigeminal ganglion. These data are consistent with activation of peripheral 5-HT2B receptors initiating PPE and the theory that selective 5-HT2B antagonists might be effective prophylactic therapies for migraine.
The Sensitivity and Specificity of the Case Definition Criteria in Diagnosis of Headache: A School-Based Epidemiological Study of 5562 Children in Mersin
Authors: Özge A , Buğdayci R , Şaşmaz T , Kaleağasi H , Kurt Ö , Karakelle A , Tezcan H , Siva A
Published: March 2003

The objectives of the present study were to estimate the prevalence of recurrent headaches in schoolchildren (ranging from 2nd to 5th degrees) in Mersin city of Turkey and to determine the sensitivity, specificity, positive predictive value and positive likelihood ratio of the diagnostic headache characteristics in children with migraine and Tension Type Headache (TTH) using neurologist's diagnosis as the gold standard. The stratified sample of study was composed of 5562 children. The prevalence of recurrent headache was 49.2% (2739 of 5562) and the prevalence of current headache was 31.3% (859 of 2739). TTH was more common than migraine (24.7% vs. 10.4%). The most sensitive headache characteristic for migraine was ‘severity of pain’ and the most sensitive definitive symptom is ‘duration of headache’ in children with TTH. IHS-based symptom definition criteria are highly beneficial in diagnosis of childhood headache, if used together with detailed clinical assessment.
Learning disability nursing staff: a response to psychiatric teaching
Authors: Haut Fabian , Hull Alistair , Irons Alison
Published: March 2003

Learning disability nursing staff have an important role in the assessment and management of dual diagnosis patients. The present study assesses the level of psychiatric knowledge and interest of nursing staff in core psychiatric topics. Nursing staff were invited to attend a series of tutorials, and their knowledge of psychiatric topics was tested via a set of multiple‐choice questions before and after the tutorials. The reasons for the low attendance rate (22%) and knowledge (47% mean correct score) are discussed. Ensuring attendance is vital because the tutorials were found to be effective in improving knowledge.
Paved with good intentions: the Hampstead and Clapton schools, 1873–1878
Authors: Stewart David S.
Published: March 2003

In terms of the history of education, most people think that 1870 saw the beginning of universal elementary education in the UK, yet few consider what provision was made for those with learning disabilities. The present paper seeks to throw light on the provision made by one authority in London, the Metropolitan Asylums Board. Prior to the establishment of the schools at Darenth in 1878, later known as Darenth Park, the Board established a school in Hampstead, and later, at Clapton for pauper children with learning disabilities. Equipped with classrooms and teachers, these were the first such schools to be funded by rates, as opposed to charitable giving. The present study will reveal that there was, in fact, a strong link with the School Board for London and that certain individuals, frustrated by constraints put on them by one authority, used their considerable skills to make provision through other routes. It was not until the 1970 Education Act that all children became entitled to education in the UK, but the example of the Hampstead and Clapton Schools reveal that attempts were being made 100 years earlier to provide rate‐funded education for children with learning disabilities. It might be regarded as a tragedy that philosophies in the intervening years did not reflect the optimism which policy makers in London held in the 1870s
Ethics in quasi‐experimental research on people with severe learning disabilities: dilemmas and compromises
Authors: Kellett Mary , Nind Melanie
Published: March 2003

The present paper follows up the theme of research ethics that has been discussed in the British Journal of Learning Disabilities in recent years. We join the debate in the capacity of people involved in doing research on, rather than with, people with learning disabilities. We focus on our own quasi‐experimental study evaluating the Intensive Interaction approach for pupils who are preverbal. We question our own practice, and illustrate some of the dilemmas which we have faced in our research and some of the compromises which we have reached.
Overcoming the barriers to voting experienced by people with learning disabilities
Authors: Bell Dorothy M. , McKay Colin , Phillips Kathryn J.
Published: March 2003

The present paper clarifies the legal situation with respect to people with a learning disability who wish to vote. It also considers other barriers to full participation in the voting franchise, which is a right that many of us see as a sign of our full participation in the democratic process and one that ensures that we have proper representation at the highest level. This paper also considers how many of the obstacles may be overcome.
Time to make up your mind: why choosing is difficult
Authors: Harris John
Published: March 2003

For many years, the promotion of choice has been a core objective for virtually every service provider working to support people with learning disability. This is confirmed by the 2001 English White Paper Valuing People, A New Strategy for Learning Disability for the 21st Century, which describes choice as one of four key principles at the heart of the UK Government's proposals, and the 2000 review of learning disability services commissioned by the Scottish Executive, People Like Us, which places a similarly high priority on the creation of choice. The present paper gives an overview of our current understanding of the concept of choice. It concludes that our aspirations to promote choice for people with learning disability are undermined by conceptual confusion about the meaning of choice, inappropriate methods for helping people to make choices and an absence of applied research to guide practice in service settings. This review is designed to establish a conceptual framework for examining choice and empowerment for people with learning disability, and to describe the implications for future research and practice.
Computing geochemical mass transfer and water/rock ratios in submarine hydrothermal systems: implications for estimating the vigour of convection
Authors: Alt‐Epping P. , Smith L.
Published: March 2003

A method of calculating chemical water/rock ratios is presented that enables the estimation of fluid velocities in open, flow‐through hydrologic systems. The approach is based on relating the gain/loss of a chemical species per kilogram of solid phase to the loss/gain of that species in the fluid phase, integrated across a specified length of the flowpath. After examining the underlying approximations of the approach using a one‐dimensional model of seawater moving through a basalt under nonisothermal conditions, the method is applied to representative zones within a two‐dimensional hydrothermal convective system. The method requires that regions within the flow system can be identified in which the direction of flow is steady for an extended period of time. Estimates of fluid velocity are spatial and temporal averages for the length of the flowpath used in the calculation. The location within the flow system and the nature of the alteration reactions determine which species can provide reliable values of the chemical water/rock ratio and useful estimates of fluid velocities. Over the length of the flowpath considered, the calculation of water/rock ratios works best when a species is controlled by a single reaction. Accurate estimates are favoured if the concentration profile of a species along the flowpath increases or decreases monotonically. If the length of the flowpath extends over more than one reaction zone, then erroneous estimates of the water/rock ratio and fluid velocity are more likely. Model calculations suggest that the quartz/silica system should provide reliable estimates for fluid velocity under a wide range of temperature and flow conditions, in particular in those regions of a system at or near quartz equilibrium, so that the aqueous silica concentration is buffered by quartz and correlated with the temperature distribution.
Episodic fluid flow within continental rift basins: some insights from field data and mathematical models of the Rhinegraben
Authors: Lampe C. , Person M. , Nöth S. , Ricken W.
Published: March 2003

Vitrinite reflectance data from a petroleum exploration well in the northern Upper Rhinegraben show an unusual vertical maturity trend. Above and below a 500 m thick marl layer the vitrinite reflectance levels are consistent with modern, conductive, geothermal gradients. Between about 1000 and 1500 m depth, however, vitrinite reflectance levels are significantly elevated (about 0.6%Ro). This anomaly cannot be explained with one‐dimensional conductive or conductive–convective heat transfer models, and thermal effects of sedimentation or igneous intrusion seem implausible for this geological setting. The thermal anomaly that formed this maturation anomaly must have been hydrothermal in origin, two‐dimensional in nature, and persisted long enough to elevate the vitrinite reflectance values within this marl unit, yet it must have dissipated before the thermal perturbation would have altered the organic matter below and above the unit.

In this study, we propose that the vitrinite reflectance anomalies were caused by a transient thermal inversion induced by episodic, lateral flow of hot (130–160°C) groundwater along conductive fractures and bedding planes. Heat flow constraints suggest that fluids must have moved rapidly up a vertical feeder fault from a depth of at least 3.6 km before migrating laterally. To test this hypothesis, we present a suite of simple, idealized mathematical models of groundwater flow, heat transfer, thermal degradation of kerogen and vitrinite systematics to explore the episodic flow that could have produced the observed thermal anomaly. In these simulations, a single, horizontal aquifer is sandwiched between two less permeable units: the total dimensions of the vertical section model are 4 km thick by 10 km long. The top of the aquifer coincides with the position of the observed thermal maturity anomaly in the Rhinegraben. Boundary conditions along the left edge of this aquifer were varied through time to allow for the migration of hot fluids out into the basin. Inflow temperature, horizontal velocity, duration and frequency of flow and thickness of the aquifer were varied. We found that a thermal maturity anomaly could only be produced by a rather restrictive set of hydrothermal conditions. It was possible to produce the observed vitrinite reflectance anomaly by a single hydrothermal flow event of 130°C fluid migrating laterally into the aquifer at a rate of 1 m a−1 for about 10 000 years. The anomaly is spatially confined to near the left edge of the basin, near the feeder fault. If the flow event lasted longer than 100 000 years, then the maturation anomaly disappeared as the lower confining unit approached steady‐state thermal conditions. It is possible that such an event occurred about 5 million years ago in response to increases in fault permeability associated with far field Alpine tectonism.
New insights from reactive transport modelling: the formation of the sericitic vein envelopes during early hydrothermal alteration at Butte, Montana
Authors: Geiger S. , Haggerty R. , Dilles J. H. , Reed M. H. , Matthäi S. K.
Published: March 2003

A reactive transport computer code has been employed to model hydrothermal alteration of a granitoid rock bordering a discrete vein channel. The model suggests that the grey sericitic and sericitic with remnant biotite alteration envelopes at the porphyry copper deposit at Butte, Montana, can be formed by a reducing, low pH, and low salinity fluid under constant temperature and pressure conditions of approximately 400 °C and less than 100 MPa during a time span of approximately 100 years or less. Hydrothermal alteration has little effect on the porosity of the host rock (Butte Quartz Monzonite), and the diffusivity of the aqueous species also changes little. A sequence of mineral reaction fronts characterizes the alteration envelopes. The biotite dissolution front occurs closest to the vein channel and marks the transition from the grey sericitic to sericitic with remnant biotite envelope. The plagioclase dissolution front occurs farthest into the matrix and marks the edge of relatively fresh Butte Quartz Monzonite. From the properties of the quasi‐stationary state approximation (Lichtner 1988; Lichtner 1991), it follows that once the sequence of reaction fronts is fully established, their relative locations remain constant and the widths of the reaction zones increase with the square root of time.
Three‐dimensional geometry, ore distribution and time‐integrated mass transfer through the quartz–tourmaline–gold vein network of the Sigma deposit (Abitibi belt, Canada)
Authors: Garofalo P. , Matthäi S. K. , Heinrich C. A.
Published: March 2003

We present a reconstruction of the three‐dimensional (3D) geometry and gold grade distribution of shear zone‐hosted, Au‐mineralized, quartz–tourmaline veins of the Sigma deposit (Abitibi belt). Host shears and veins form a network of anastomosing, steeply dipping structures associated with smaller subhorizontal extensional veins. Our reconstruction has been carried out using the exceptionally large geological database of the mine. From this database, we extracted the geometric position, thickness and gold grades of geometrically best‐defined steep veins contained in a representative subvolume of the deposit. These data allowed the 3D representation of 53 veins, which have been constructed by fitting surfaces through the geometrical data and by contouring thickness and gold grade. The geometry of the network is mainly characterized by: (i) a few large segmented veins, with sinuous and helicoidal shape, and typical vertical dimension of >100 m; (ii) a large number of smaller vertical veins, some of which splay off the steep veins with high dip angles; (iii) subhorizontal extension veins (joints) located at, or close to, the tips of steep veins. The absolute thickness of the vertically short veins is the same as that of the large veins, suggesting that they formed simultaneously, but only a few of them interconnect to form vertically continuous bodies. Patchy, vertically elongated zones of high dilation are present in the large veins, and are poorly correlated with Au‐rich zones. They presumably represent former high‐permeability zones of the network. The highest gold grades occur at the interconnections between the large veins and small splays or subhorizontal joints. This indicates the important role of vein interconnection for fluid flow and gold precipitation within the network. Combining the calculation of the volume of the network with the estimation of tourmaline abundance in the veins, we calculate that 2.1 × 106 m3 of tourmaline and 3.2 × 106 m3 of quartz precipitated during Au deposition.
The potential for baker’s yeast (Saccharomyces cerevisiae) in the production of wine from banana, cooking banana and plantain
Authors: Onwuka, U. N. , Awam F. N.
Published: March 2003

Musa species (banana, cooking banana and plantain) were bought from a market in Umuahia Abia State, Nigeria. Samples were chemically analysed and subsequently used in wine production by conventional methods of must preparation, filtration, primary and secondary fermentation (with baker’s yeast as inoculum), pasteurization and bottling. Physical–chemical properties and microbial content were monitored during the process. Sensory characteristics of the Musa wines were evaluated. The Musa species were found to have a fermentable sugar level of 18.81–23.57%. The wines produced showed an alcohol content of 9.96–11.25, brix (scale of densities used in the sugar industry) level 8.00–8.15, ash 0.32–0.45, and titratable acidity 1.00–1.108. Sensory evaluation indicated a significant difference in taste, colour and general acceptability at P < 0.05 among the wines. Potential opportunities exist to develop and produce local fruit wines for consumption by both the domestic market and tourists.
Water temperature as a factor in handwashing efficacy
Authors: Michaels Barry , Gangar Vidhya , Schultz Ann , Arenas Maria , Curiale Michael , Ayers Troy , Paulson Daryl
Published: March 2003

For many years, sanitarians have specified that the hands of food service workers should be washed and rinsed in warm or hot water to reduce the risk of cross‐contamination and disease transmission. In the food service environment, it has been suggested that handwashing with water at higher temperatures contributes to skin damage when frequent handwashing is necessitated, and that insistence on hot water usage is a deterrent to handwashing compliance. Separate handwashing studies involving different water temperatures and soap types (antibacterial versus non‐antibacterial) were performed. The ‘glove‐juice’ technique was employed for microbial recovery from hands in both studies. Initial work evaluated antimicrobial efficacy based on water temperature during normal handwashing with bland soap. Uninoculated, sterile menstrua (tryptic soy broth or hamburger meat) was used to study the effects of treatment temperatures (4.4°C, 12.8°C, 21.1°C, 35°C or 48.9°C) on the reduction of resident microflora, while Serratia marcescens‐inoculated menstrua was used to evaluate treatment effects on the reduction of transient contamination. Results of this first study indicated that water temperature exhibits no effect on transient or resident bacterial reduction during normal handwashing with bland soap. The follow‐up study examined the efficacy and skin irritation potential involving water temperatures with antimicrobial soaps. Hands of participants were contaminated with Escherichia coli inoculated ground beef, washed at one of two water temperatures (29°C or 43°C) using one of four highly active (USDA E2 equivalency) antibacterial soaps having different active ingredients (PCMX, Iodophor, Quat or Triclosan). Skin condition was recorded visually and with specialized instrumentation before and after repeated washing (12 times daily), measuring total moisture content, transepidermal water loss and erythema. Overall, the four soap products produced similar efficacy results. Although there were slight increases in Log10 reductions, visual skin irritation, loss of skin moisture content and transepidermal water loss at higher temperatures, results were not statistically significant for any parameter.
Chefs’ attitudes in North‐Eastern US toward irradiated beef, Olestra, rBST and genetically engineered tomatoes
Authors: Crowley Mary L. , Gaboury Donna J. , Witt David
Published: March 2003

Social and economic factors, such as cost, income, attitudes, availability and convenience have traditionally impacted consumer food choices. Newer determinants of food choice include the effects of legislation, technology and the increase in percentage of meals eaten outside the home (45% today, projected to be 53% by 2010). In this decade, controversial food technologies include irradiation, genetic engineering and and development of non‐digestible fat substitutes. With higher frequency of meals eaten outside the home, there is an increase in transfer of decision making from individuals and families to chefs. This study surveyed 115 chefs for their awareness of and willingness to purchase such technically altered foods. Chefs were also queried concerning support for labeling for genetically modified ingredients and foods. Irradiated ground beef and genetically engineered tomatoes had high levels of willingness to purchase; potato chips made with Olestra had the lowest level of willingness to purchase. Chefs supported mandatory labeling of food containing genetically modified ingredients.
Alien plant assemblages near roads in arid and semi‐arid South Africa
Authors: Milton S. J. , Dean W. R. J.
Published: March 2003

Herbaceous and woody alien plants visible from a moving vehicle were recorded along 1 km roadside transects at 5 km intervals over a distance of 5869 km in the semi‐arid and arid Fynbos, Succulent Karoo, Nama Karoo and Arid Savanna (Kalahari) biomes in South Africa. Each 1 km transect was classified by biome and vegetation type, mean annual rainfall, rainfall seasonality, soil surface type and landuse adjoining the roadside. Although travelling speed affected the range and frequency of plant species observed, the method was repeatable at a speed of 100 km h−1. Alien plants occurred in 98% of 119 Fynbos, 81% of 204 Succulent Karoo, 72% of 661 Nama Karoo, 47% of 171 Arid Savanna and 100% of seventeen Grassland transects. Alien species richness per site was correlated with mean annual rainfall, but in all regions, sites adjacent to cultivation had significantly more alien species than sites adjoining rangeland. The alien plant assemblage of the arid winter‐rainfall Succulent Karoo included species from mesic winter‐rainfall lowland Fynbos and the arid Nama Karoo receives unseasonal rainfall. The frequencies of Prosopis spp., Atriplex spp. and Opuntia ficus‐indica were not significantly greater near cultivation, and these perennial plants, all of which are dispersed by indigenous and domestic animals, can invade natural rangeland in arid and semi‐arid southern Africa.
Landscape heterogeneity, connectivity, and critical landscapes for conservation
Authors: Malanson George P. , Cramer Barton E.
Published: March 2003

Landscapes are diverse in the frequencies and distributions of habitat types. Does landscape heterogeneity, as a higher order (i.e. at a pheno‐ menological scale coarser than that of organisms) of diversity, allow greater connectivity; does higher order diversity change higher order functions? Climatic change and habitat fragmentation require that plant and animal species move across varied landscapes. Mediterranean‐type ecosystems provide contrasts in landscape heterogeneity. In order to assess potential impacts of either and thus to propose remedial measures, it is necessary to understand general classes of connectivity in landscapes. We developed six rules for movement (random, persistent, and directionally biased for both movement throughout habitat and restricted to habitat edges), which we simulated on three general landscape patterns (random, hierarch‐ ical, and fractal) with different degrees of habitat fragmentation. Organisms that move only on the edge of habitat patches are more successful with a moderate amount of fragmentation but are less successful overall and especially in the non‐random landscapes. Particular structures can thus differentiate connectivity for different vectors. We propose that general rules derived from simulations can be applied to the identification of landscapes that are near critical levels of fragmentation and which will respond sensitively to small increases in fragmentation or small efforts at restoration. Mediterranean‐type ecosystems are well suited to test this proposal because of contrasting patterns and changes in fragmentation.
Grasshopper (Orthoptera: Acridoidea) species diversity in the Pampas, Argentina
Authors: Cigliano María Marta , De Wysiecki María Laura , Lange Carlos E.
Published: March 2003

Abstract.  A study was conducted to describe the major features of geographical and temporal variation in the diversity of grassland grasshopper species (Orthoptera: Acridoidea) in different sites of the Pampas, Argentina. Species richness and relative abundance were assessed at 12 sites in eastern La Pampa and western Buenos Aires provinces, from 1994 through 1999. Mean species richness at the regional level was 10, and 34 grasshopper species were collected throughout of the study. Comparison with grasshopper species diversity from the Great Plains of North America is discussed. An evaluation of the proportions of species in each of the three distribution groups (broad, intermediate and narrow) revealed that, over all sites, broadly distributed species made up 14.7% of species composition and intermediately and narrowly distributed species made up 26.5% and 58.8%, respectively. The three top‐ranked species in the studied sites were Dichroplus elongatus, D. pratensis and Staurorhectus longicornis. Results showed that, contrary to what was expected, one of the widely distributed species in the region (i.e. Baeacris punctulatus) does not always constitute one of the most abundant species. Finally, the loss of one of the historically most common species in the Pampas, D. maculipennis, is also discussed.
Native and naturalized plant diversity are positively correlated in scrub communities of California and Chile
Authors: Sax Dov F.
Published: March 2003

Abstract. An emerging body of literature suggests that the richness of native and naturalized plant species are often positively correlated. It is unclear, however, whether this relationship is robust across spatial scales, and how a disturbance regime may affect it. Here, I examine the relationships of both richness and abundance between native and naturalized species of plants in two mediterranean scrub communities: coastal sage scrub (CSS) in California and xeric‐sloped matorral (XSM) in Chile. In each vegetation type I surveyed multiple sites, where I identified vascular plant species and estimated their relative cover. Herbaceous species richness was higher in XSM, while cover of woody species was higher in CSS, where woody species have a strong impact upon herbaceous species. As there were few naturalized species with a woody growth form, the analyses performed here relate primarily to herbaceous species. Relationships between the herbaceous cover of native and naturalized species were not significant in CSS, but were nearly significant in XSM. The herbaceous species richness of native and naturalized plants were not significantly correlated on sites that had burned less than one year prior to sampling in CSS, and too few sites were available to examine this relationship in XSM. In post 1‐year burn sites, however, herbaceous richness of native and naturalized species were positively correlated in both CSS and XSM. This relationship occurred at all spatial scales, from 400 m2 to 1 m2 plots. The consistency of this relationship in this study, together with its reported occurrence in the literature, suggests that this relationship may be general. Finally, the residuals from the correlations between native and naturalized species richness and cover, when plotted against site age (i.e. time since the last fire), show that richness and cover of naturalized species are strongly favoured on recently burned sites in XSM; this suggests that herbaceous species native to Chile are relatively poorly adapted to fire.
Pharmacokinetics of alizapride in children receiving chemotherapy for solid tumour
Authors: Rey Elisabeth , Stettler Eric , D'Athis Philippe , Pons Gérard
Published: March 2003

The purpose of the present study was to determine the pharmacokinetics of alizapride to optimize its use in children aged 1 month to 15 years old who were receiving chemotherapy. Seventeen children were given a single 4 mg/kg alizapride infusion prior to the administration of cytostatic drugs. Blood and urine samples were collected within 10 h after onset of the infusion. Kinetic parameters were calculated and showed a decrease in plasma clearance expressed per unit of body weight with age. The current data suggest that dosage expressed per unit of body weight should be higher in children than in adults and higher in infants than in children.
Blood pressure and vascular reactivity to endothelin‐1, phenylephrine, serotonin, KCl and acetylcholine following chronic alcohol consumption in vitro
Authors: Utkan Tijen , Yildiz Firuzan , Ilbay Gül , Özdemirci Sitki , Erden Bekir Faruk , Gacar Nejat , Ulak Güner
Published: March 2003

Ethanol has been reported to cause hypertension, the mechanism of which is unknown. Therefore, the effect of chronic ethanol consumption on vascular responsiveness and blood pressure was investigated. Systolic blood pressure was recorded weekly by tail‐cuff method. Aortic rings from rats fed chow ad libitum or pair‐fed liquid diets containing either ethanol (7.2% v/v) or isocaloric carbohydrate for 4 weeks were placed in organ chambers for isometric tension measurement. There was a mild but significant elevation of the systolic blood pressure in the alcohol‐fed rats by week 1 compared to baseline measurements and this remained higher. No significant changes in reactivity of rat isolated aortas to phenylephrine, serotonin, endothelin‐1 (ET‐1) and KCl were seen in chronic ethanol consumption. In addition, the sensitivity (i.e. pD2) of alcohol‐fed aortic rings to the vasoconstrictors was also unchanged compared to controls. Chronic ethanol consumption, however, increased relaxation to acetylcholine with increased pD2 values, but did not alter relaxation to sodium nitroprusside, a cyclic guanosine monophosphate (cGMP)‐dependent direct smooth muscle dilator. The results indicate that chronic ethanol consumption significantly potentiates endothelium‐dependent relaxations in aortic rings, probably through interference with the production and/or the release of nitric oxide (NO) or adaptive alterations in muscarinic receptors on the endothelial cells, and that increased vascular responsiveness to several vasoconstrictors is not a mechanism responsible for the blood pressure elevation in the chronic alcohol consumption in rats.
Role of K+‐channels in homotaurine‐induced analgesia
Authors: Serrano Maria Isabel , Serrano José S. , Asadi Ikhlas , Fernández Ana , Serrano‐Martino Maria Carmen
Published: March 2003

In previous articles, antinociceptive activity for homotaurine has been demonstrated to be mediated by opioid, GABAergic and cholinergic mechanisms. GABAB‐agonists affect K+‐channels and it is known that K+‐channels modulate specific activation of opioid receptors. In this study, we examined the involvement of K+‐channels in the antinociceptive activity of homotaurine (22–445 mg/kg). Antinociceptive response was obtained after icv pretreatment with the channel specific blockers 4‐aminopyridine (voltage‐dependent channels), tetraethylammonium (Ca++ and voltage‐dependent) and gliquidone (ATP‐dependent). The nociceptive tests performed were acetic acid induced abdominal constriction (mice) and tail flick (rats) tests. Acetic acid responses to homotaurine were inhibited by tetraethylammonium (5 μg) and gliquidone (16 μg). Tail flick response to homotaurine was inhibited by tetraethylammonium (50 μg), gliquidone (40 and 80 μg) and 4‐aminopyridine (25 and 250 ng). These results suggest an involvement of the three types of K+‐channels in antinociception by homotaurine, depending on specific homotaurine and blocker doses. At a spinal level, they appear to be involved together with GABAB and opioid mechanisms. Peripherally, only tetraethylammonium channels would be substantially activated during homotaurine antinociceptive effect.
Effects of six antihypertensive drugs on blood pressure and hypothalamic GABA content in spontaneously hypertensive rats
Authors: Guan Ying , Miao Chao‐Yu , Su Ding‐Feng
Published: March 2003

In order to investigate the effects of antihypertensive drugs on blood pressure and γ‐amino butyric acid (GABA) content in the hypothalamus and the possible relationship between blood pressure decrease and GABA content changes, blood pressure and GABA contents after chronic (20 weeks) treatments of nitrendipine, atenolol, captopril, hydrochlorothiazide, dihydralazine and prazosin were studied in spontaneously‐hypertensive rats (SHR). The acute and subacute (1 week) effects of nitrendipine on GABA contents was also observed in SHR. It was found that 20 week treatments with six different antihypertensive agents produced a decrease in systolic blood pressure and an increase in GABA content. The blood pressure level was significantly correlated with GABA content in the hypothalamus, but not with that in the cortex. Acute treatment with a single dose of nitrendipine, did not alter GABA content. Bicuculline, a GABA receptor antagonist, did not attenuate the hypotensive effect of nitrendipine. In conclusion, chronic treatments by different antihypertensive agents produced an increase of hypothalamic GABA content and a decrease of blood pressure. The increase of GABA content induced by nitrendipine seems likely to be secondary to blood pressure decrease.
Effects of tramadol on behavioural indicators of colic pain in a rat model of ureteral calculosis
Authors: Affaitati Giannapia , Giamberardino Maria Adele , Lerza Rosanna , Lapenna Domenico , De Laurentis Silvana , Vecchiet Leonardo
Published: March 2003

This study investigated the effect of prolonged administration of tramadol vs. placebo on behavioural indicators of ureteral pain and referred lumbar muscle hyperalgesia in a rat model of artificial ureteral calculosis.

Four groups of 10 rats each (female, Sprague‐Dawley) were treated twice a day, for 4 days, with i.p. injections of tramadol 1.25 mg/kg, 2.5 mg/kg, 5 mg/kg or saline, respectively. The first injection was delivered 45 min before laparotomy (under pentobarbital anaesthesia) for formation of the stone in the upper left ureter via injection of dental cement. All rats were video‐taped 24 h non‐stop from the immediate postoperative period until the 4th day for recording of behavioural ureteral crises indicative of colic pain. Lumbar muscle sensitivity was tested daily over the same period by verifying presence or absence of vocalization upon pinching of the parietal layers at L1 level, bilaterally, at a constant predefined pressure value with calibrated forceps.

Tramadol significantly reduced number and global duration (ANOVA, P < 0.008 and P < 0.004) of ureteral crises with respect to saline and the effect was dose‐dependent (linear regression analysis between doses and parameters of crises, P < 0.003 and P < 0.002). The drug also significantly reduced the incidence of referred muscle hyperalgesia (ANOVA, P < 0.0001). It is concluded that tramadol is highly effective in controlling pain phenomena from urinary stones and can represent a valid therapeutic approach in patients with urinary colics.
New insights in insurmountable antagonism
Authors: Vauquelin G. , Van Liefde I. , Birzbier B. B. , Vanderheyden P. M. L.
Published: March 2003

Antagonists that produce parallel rightward shifts of agonist dose–response curves with no alteration of the maximal response are traditionally classified as surmountable, while insurmountable antagonists also depress the maximal response. Although the longevity of the antagonist–receptor complex is quoted in many studies to explain insurmountable antagonism, slowly interconverting receptor conformations, allosteric binding sites, and receptor internalization have been evoked as alternative explanations. To complicate matters even further, insurmountable antagonism is not only drug‐related; it may also depend on the tissue, species and experimental design. For the sake of drug development, it is important to elucidate the molecular mechanisms of insurmountable antagonism. New experimental approaches, such as intact cell studies and the use of computer‐assisted simulations based on dynamic receptor models, herald the advent of better insight in the future.
In vitro effects of tacrolimus on human cytochrome P450
Authors: Lecointre K. , Furlan V. , Taburet A.‐M.
Published: March 2003

Tacrolimus, a potent immunosuppressive drug, is known to be metabolized predominantly in the liver by cytochrome P450 3A (CYP3A). In order to determine the potential of tacrolimus to inhibit the metabolism of other drugs, we have investigated its inhibitory effects on specific cytochrome reactions. Specific substrates for the seven cytochromes (CYPs) 1A2, 2A6, 2C9, 2C19, 2D6, 2E1 and 3A4/5 were incubated with human hepatic microsome preparations with or without specific inhibitors or tacrolimus and the metabolites were detected by high‐pressure liquid chromatography (HPLC) or fluorimetric methods. All the specific inhibitors reduced or abolished the specific CYP activity. Tacrolimus had no effect on any CYP at concentrations below 1 µm, while at higher concentrations it had a mild inhibitory effect on CYP3A4 and 3A5. These observations suggest that tacrolimus is unlikely to potentiate the effect of coadministered drugs through inhibition of their metabolism in the liver.
In vivo quantitative near‐infrared spectroscopy in skeletal muscle during incremental isometric handgrip exercise
Authors: Van Beekvelt Mireille C. P. , Van Engelen Baziel G. M. , Wevers Ron A. , Colier Willy N. J. M.
Published: March 2003

The aim of this study was to investigate the performance of in vivo quantitative near‐infrared spectroscopy (NIRS) in skeletal muscle at various workloads. NIRS was used for the quantitative measurement of O2 consumption (mV˙O2) in the human flexor digitorum superficialis muscle at rest and during rhythmic isometric handgrip exercise in a broad range of work intensities (10–90% MVC=maximum voluntary contraction force). Six subjects were tested on three separate days. No significant differences were found in mV˙O2 measured over different days with the exception of the highest workload. The within‐subject variability for each workload measured over the three measurements days ranged from 15·7 to 25·6% and did not increase at the high workloads. The mV˙O2 was 0·14 ± 0·01 mlO2 min–1 100 g–1 at rest and increased roughly 19 times to 2·68 ± 0·58 mlO2 min–1 100 g–1 at 72% MVC. These results show that local muscle oxygen consumption at rest as well as during exercise at a broad range of work intensities can be measured reliably by NIRS, applied to a uniform selected subject population. This is of great importance as direct local measurement of mV˙O2 during exercise is not possible with the conventional techniques. The method is robust enough to measure over separate days and at various workloads and can therefore contribute to a better understanding of human physiology in both the normal and pathological state of the muscle.
Non‐linear behaviour of respiratory movement in obstructive sleep apnoea syndrome
Authors: Miyata Masanori , Burioka Naoto , Suyama Hisashi , Sako Takanori , Nomura Takashi , Takeshima Takao , Higami Shigeru , Shimizu Eiji
Published: March 2003

In this study we investigated the non‐linear properties of respiratory movement in patients with obstructive sleep apnoea syndrome (OSAS) during sleep without and with nasal continuous positive airway pressure (nCPAP). To calculate the correlation dimension (D2) in respiratory movement we applied an algorithm proposed by Grassberger and Procaccia. Non‐linearity in respiratory movement was tested by comparing D2 for the original data with that for surrogate data. Respiratory movement was recorded from 10 patients with OSAS. D2 during both wakefulness with eyes closed and during sleep with nCPAP at 8 cm H2O could be computed in all subjects (2·50 ± 0·69 and 1·68 ± 0·17, respectively). On the other hand, D2 during sleep with apnoea could not be computed in patients with severe OSAS. These results indicate the abnormal properties of respiratory movement during apnoeic sleep in severe OSAS. Moreover, respiratory movement with nCPAP was shown to be non‐linear deterministic behaviour in respiratory movement during sleep. Analysis of D2 for respiratory movement may be useful in adjusting (titrating) nCPAP and classifying severity in OSAS.
Criteria Used for Protection of Natural Areas in Sweden 1909–1986
Authors: GÖTMARK FRANK , NILSSON CHRISTER
Published: March 2003

Abstract: We examined 15 criteria used for selection of 1175 natural areas protected by the Swedish Nature Conservation Act. We categorized criteria as “scientific,” having botanical, ornithological, and geological values, or “political,” having human‐oriented recreational, landscape, and cultural values. On average, 2.3 criteria were used per protected area, and number of criteria increased with size of area. The six major criteria in order of use were: recreational, botanical, landscape, geological, ornithological, and cultural values. Political criteria were as important as scientific ones for protection of Swedish nature. There were only minor historical changes in use of different criteria, except that recreational values increased strongly from 1965 to 1975. The average and median size of protected areas increased from 1960 onwards. Areas of recreational value were more common close to the three largest cities and were often large; areas of botanical value were often small. Areas of recreational or ornithological value were associated with lakes and the coast; areas of botanical and landscape value were associated with mountain and farmland. An ordination of areas with two or more criteria showed associations within the group of political and within the group of scientific criteria. Political criteria may be important in or close to populated areas during periods when urbanization and leisure increase; nationally, we plead for emphasis on biological criteria in future selection of protected areas.
Policies for the Enforcement of Wildlife Laws: The Balance between Detection and Penalties in Luangwa Valley, Zambia
Authors: Leader‐Williams N. , Milner‐Gulland E.J.
Published: March 2003

Models have shown that levels of law enforcement in Luangwa Valley, Zambia, during the 1980s were not adequate to prevent illegal exploitation of black rhinos and African elephants. Theory suggests that the deterrent effect of an increase in detection rate will be larger than that of a similar increase in penalty. The most effective penalty, in economic terms, would be a variable fine related to the number of illegal trophies harvested, but this may be hard to legislate effectively. Wildlife managers conserving rhinos and elephants should focus on improving detection rates rather than on requesting severe penalties with no improvements in detection.