bluuebunny/crossref_metadata_2025 huggingface dataset:
A structured health needs assessment tool: acceptability and effectiveness for health visiting
Authors: Cowley Sarah , Houston Anna M.
Published: June 2003

Background. There is, nominally at least, a universal health visiting service in Great Britain, although the frequency of contacts may be severely restricted. Debates about whether home visiting should be universal or selective, therefore, focus on whether health visitors should use professional judgement or structured assessment tools to target attention within their caseload. Research attention has focused mainly on unstructured needs assessments and professional judgment or the development of assessment tools, so that the views of practitioners using structured instruments and their clients are not known.

Methods. A two‐phase qualitative study examined the acceptability and effectiveness of a structured health needs assessment tool (HNAT) implemented in London. Views about the tool were elicited from 30 health visitors through telephone interview, and then 21 assessments were observed and tape‐recorded; 19 clients were interviewed after the event. Data were evaluated for adequate coverage of views across the target population and analysed using the framework approach.

Findings. A range of views were expressed, but the HNAT caused anxiety and distress to, particularly, the most vulnerable clients. The structured format of the tool appeared to encourage the health visitors to question instead of listen. It did not help to identify all the needs and intruded into normal practice in an insensitive and unhelpful way.

Limitations. This study investigated only one form of structured HNAT. These are commonly used to prioritize undifferentiated needs of clients who have been offered an unsolicited, health promoting service. Our findings therefore do not apply to validated instruments used for screening or specific diagnostic purposes where a client has requested help with a problem.

Conclusions. Given the problems in use and potential for harm, this form of structured assessment tool appears unsuitable for routine use to determine the intensity of health visiting contacts.
Post‐ice age recolonization and differentiation of Fucus serratus L. (Phaeophyceae; Fucaceae) populations in Northern Europe
Authors: Coyer J. A. , Peters A. F. , Stam W. T. , Olsen J. L.
Published: June 2003

The seaweed Fucus serratus is hypothesized to have evolved in the North Atlantic and present populations are thought to reflect recolonization from a southern refugium since the last glacial maximum 18 000–20 000 years bp. We examined genetic structure across several spatial scales by analysing seven microsatellite loci in populations collected from 21 localities throughout the species’ range. Spatial auto‐correlation analysis of seven microsatellite loci revealed no evidence for spatial clustering of alleles on a scale of 100 m despite limited gamete dispersal in F. serratus of ≈ 2 m from parental individuals. Pairwise θ analysis suggested that the minimal panmictic unit for F. serratus was between 0.5 and 2 km. Isolation by distance was significant along some contiguous coastlines. Population differentiation was strong within the Skagerrak–Kattegat–Baltic Seas (SKB) (global θ= 0.17) despite a short history of ≈ 7500 years. A neighbour‐joining tree based on Reynold's distances computed from the microsatellite data revealed a central assemblage of populations on the Brittany Peninsula surrounded by four well‐supported clusters consisting of the SKB, the North Sea (Ireland, Helgoland), and two populations from the northern Spanish coast. Samples from Iceland and Nova Scotia were most closely aligned with northwest Sweden and Brittany, respectively. When sample sizes were standardized (N = 41), allelic diversity was twofold higher for Brittany populations than for populations to the north and threefold higher than southern populations. The Brittany region may be a refugium or a recolonized area, whereas the Spanish populations most likely reflect present‐day edge populations that have undergone repeated bottlenecks as a consequence of thermally induced cycles of recolonization and extinction.
Calibrating phylogenetic species formation in a threatened insect using DNA from historical specimens
Authors: Goldstein Paul Z. , Desalle Rob
Published: June 2003

Museum specimens from the late 19th and early 20th centuries were surveyed for the single nucleotide polymorphism identified previously and used to diagnose populations of the federally threatened Northeastern Beach Tiger Beetle Cicindela d. dorsalis (Coleoptera: Carabidae). Widespread polymorphism was revealed throughout the historical range of this species, suggesting a relatively recent anthropogenic character fixation event associated with the extinction and fragmentation of populations. Implications for the phylogenetic species criterion and for the reintroduction of individuals to formerly occupied sites are discussed.
Effects of Wolbachia on mtDNA variation in two fire ant species
Authors: Dewayne Shoemaker D. , Keller Gwen , Ross Kenneth G.
Published: June 2003

Wolbachia are endosymbiotic bacteria that infect arthropods. As they are maternally transmitted, the spread of Wolbachia variants within host populations may affect host mtDNA evolution. We sequenced a portion of the mitochondrial cytochrome oxidase I gene from numerous individuals of two Wolbachia‐infected fire ant species, Solenopsis invicta and S. richteri, to determine how these bacteria influence patterns of mtDNA variation. As predicted, there was a strong association between Wolbachia strain and host mtDNA lineage within and between these fire ant species. However, there was no consistent association between the presence of Wolbachia and a reduction in mtDNA diversity. Moreover, patterns of mtDNA variation within Wolbachia‐infected populations did not differ consistently from neutral expectations, despite our prediction that strong positive selection acting on Wolbachia influences the evolutionary dynamics of other cytoplasmic genomes. Specifically, while values of Tajima's D consistently were less than zero for all six samples of fire ants harbouring Wolbachia, MacDonald–Kreitman tests suggested that the patterns of variation were different from those expected under neutrality in only two of the samples. We conclude that these neutrality tests do not unambiguously reveal a clear effect of Wolbachia infection on patterns of mtDNA variation and substitution in fire ants. Finally, consistent with an earlier study, our data revealed the presence of two divergent mtDNA haplotype lineages and Wolbachia strains within S. invicta. Recognition of these two lineages has important consequences for interpreting patterns of mtDNA evolution and genetic differentiation between conspecific social forms of this species.
Population genetics of an invasive species, Heracleum mantegazzianum: implications for the role of life history, demographics and independent introductions
Authors: Walker N. F. , Hulme P. E. , Hoelzel A. R.
Published: June 2003

The population genetic structure of an invasive, nonindigenous riparian weed (Heracleum mantegazzianum) in the northeast of England was investigated using microsatellite DNA markers. Data were used to assess the size and frequency of introductions into three catchments and the subsequent spread. We sampled 13 populations, including a remote population (Perivale, London) for comparison. Five loci were screened and considerable variation was found. Results revealed greater overall variation between populations from different catchments than those in the same catchment, and suggested the generation of population structure in the relatively short time since the initial introduction. Between‐catchment variation may reflect population structure generated by local founders as the species spread and may indicate a large initial founder population at the time of the introduction into Britain, or multiple introductions. Within‐catchment variation was consistent with expectations based on the water‐borne dispersal of seeds in this species, and the relatively small dispersal range of likely pollinators. Independent introductions stand out in some cases as exceptions to the general pattern. Taken together the results are consistent with a relatively large initial founder population, and the subsequent spread of the species in local founder populations, followed by some level of inbreeding within local populations and novel introductions in some localities.
Landscape location affects genetic variation of Canada lynx (Lynx canadensis)
Authors: Schwartz M. K. , Mills L. S. , Ortega Y. , Ruggiero L. F. , Allendorf F. W.
Published: June 2003

The effect of a population's location on the landscape on genetic variation has been of interest to population genetics for more than half a century. However, most studies do not consider broadscale biogeography when interpreting genetic data. In this study, we propose an operational definition of a peripheral population, and then explore whether peripheral populations of Canada lynx (Lynx canadensis) have less genetic variation than core populations at nine microsatellite loci. We show that peripheral populations of lynx have fewer mean numbers of alleles per population and lower expected heterozygosity. This is surprising, given the lynx's capacity to move long distances, but can be explained by the fact that peripheral populations often have smaller population sizes, limited opportunities for genetic exchange and may be disproportionately affected by ebbs and flows of species’ geographical range.
Temporal Variation in Cleanerfish and Client Behaviour: Does It Reflect Ectoparasite Availability?
Authors: Côté Isabelle M. , Molloy Philip P.
Published: June 2003

We tested the importance of ectoparasites as the proximate cause of cleaning interactions by comparing the activity of Caribbean cleaning gobies (Elacatinus evelynae) and of their clients during three daily periods (early morning, midday, and late afternoon) in which ectoparasite availability varied naturally. Emergence from the benthos of gnathiid isopod larvae, the main target of cleaning goby predation, was higher at night, when cleaners were inactive, than during the day. As a result, overall ectoparasite loads on client fish tended to be higher in the morning. Inspection bouts by cleaning gobies were longest in the morning, but also at midday when ectoparasite availability on clients was lower. Client fish were observed at cleaning stations most often in the afternoon, when they harboured few ectoparasites, but they were more likely to adopt incitation poses, which increase the likelihood of being cleaned, in the morning than later in the day. Most cleaner and client behaviours therefore did not change predictably in response to natural diurnal variation in ectoparasite availability. Our study suggests that the ultimate and proximate causes of cleaning behaviour need not necessarily coincide.
Age Differences in the Response of Willow Tits (Parus montanus) to Conspecific Alarm Calls
Authors: Rajala Mari , Rätti Osmo , Suhonen Jukka
Published: June 2003

Predation is an important mortality factor in wintering birds. To counter this, birds produce alarm calls in the presence of predators which serve to warn conspecifics. In social hierarchical bird flocks, adults survive the winter better than juveniles and therefore survival strategies probably vary with social status. This study examined the differential responses to alarm calls by free‐living willow tits, Parus montanus, in dominance‐structured winter flocks in Finland. To explore the age‐dependent differences in response to conspecific alarm calls, a series with three alarm calls was played to focal adults and juveniles while they sat in the middle section of a spruce branch. Immediately after the playback, juvenile willow tits moved more often, flew longer distances and changed branches more often than did adults. Previous mammal studies have shown that juveniles are more likely to flee than adults after hearing conspecific alarm calls. The current study demonstrates that similar age‐dependent responses to conspecific alarm calls occur in birds also. These findings reflect an increased vulnerability to predators or lack of experience of young birds.
Antipredator Tactics of Amphibious Sea‐Snakes (Serpentes, Laticaudidae)
Authors: Shine Richard , Bonnet Xavier , Cogger Harold G.
Published: June 2003

Because the antipredator behavior that an animal displays depends upon the context in which it encounters the predator, apparent interspecific differences in antipredator tactics may result from ecological rather than behavioral differences among taxa. We approached 127 free‐ranging laticaudid sea‐snakes on small islands in Noumea Lagoon, New Caledonia, prodded the animals midbody, and recorded their responses. One species (Laticauda colubrina) usually remained immobile (relying on crypsis) whereas another (L. laticaudata) generally fled. However, multivariate analysis shows that the two species actually responded in very similar ways to any given stimulus; the species differed overall because colubrina was generally encountered on land during the day whereas laticaudata was more often encountered in the ocean at night. Thus, apparent interspecific differences in antipredator responses were secondary consequences of interspecific differences in the times and places that predators were encountered. Snakes were more likely to flee rather than remain immobile when rapid locomotion was possible (i.e. juveniles rather than adults; in water rather than on land) and pursuit by a predator was difficult (i.e. at night rather than during the day). These patterns suggest that snakes adjust their antipredator tactics in ways that maximize the chances of surviving the encounter, although the remarkable docility of these highly venomous snakes remains puzzling.
Deterministic Plio‐Pleistocene extinctions in the European cool‐temperate tree flora
Authors: Svenning Jens‐Christian
Published: June 2003

Extinctions have been important in the shaping of modern phytogeographic patterns. A classic example is the heavy Plio‐Pleistocene losses that have caused Europe to have a depauperate temperate tree flora compared to eastern North America and eastern Asia. To investigate the mechanisms involved in this extinction event, I test the hypothesis that the present European status (extinct, relictual, or widespread) of cool‐temperate tree genera found in Pliocene Europe is predictable from their modern climatic requirements. As a prerequisite for this analysis, I test for genus‐level conservatism in climatic requirements by comparing congeneric values across Europe, eastern Asia and North America, and find strong evidence hereof. I find a high degree of ecological determinism in the fate of European Pliocene tree genera, still widespread taxa being more tolerant of cold growing season and winter temperatures than extinct and relictual taxa, and relictual taxa being more drought tolerant than extinct taxa.
How should environmental stress affect the population dynamics of disease?
Authors: Lafferty Kevin D. , Holt Robert D.
Published: June 2003

abstract

We modelled how stress affects the population dynamics of infectious disease. We were specifically concerned with stress that increased susceptibility of uninfected hosts when exposed to infection. If such stresses also reduced resources, fecundity and/or survivorship, there was a reduction in the host carrying capacity. This lowered the contact between infected and uninfected hosts, thereby decreasing transmission. In addition, stress that increased parasite mortality decreased disease. The opposing effects of stress on disease dynamics made it difficult to predict the response of disease to environmental stress. We found analytical solutions with negative, positive, convex and concave associations between disease and stress. Numerical simulations with randomly generated parameter values suggested that the impact of host‐specific diseases generally declined with stress while the impact of non‐specific (or open) diseases increased with stress. These results help clarify predictions about the interaction between environmental stress and disease in natural populations.
Impairment of Trigeminal Sensory Pathways in Cluster Headache
Authors: van Vliet JA , Vein AA , Le Cessie S , Ferrari MD ,   JG van Dijk for the Dutch RUSSH Research Group
Published: June 2003

Cluster headache (CH) typically presents in clusters of attacks of intense (peri)orbital, unilateral pain. The distribution of the pain implies involvement of central and/or peripheral trigeminal pathways. These can be investigated by means of trigeminal somatosensory evoked potentials (TSEP) and blink reflexes (BR). We aimed to relate functional changes in trigeminal sensory pathways to the presence of cluster periods. TSEP and BR were performed in 28 episodic CH patients during a cluster period and repeated in 22 outside a cluster period. TSEP latencies (N1, P1 and N2) and amplitude (N1-P1 and P1-N2) and BR latencies (R1, R2 ipsilateral and R2 contralateral) were compared between sides, during and outside a cluster period and with healthy control data ( n = 22). During a cluster period, N2 TSEP latencies were longer on the symptomatic side compared with the non-symptomatic side (27.2 ± 3.0 ms vs. 26.3 ± 3.4 ms, P = 0.02), and compared with the same side outside the cluster period (26.7 ± 3.1 ms vs. 25.1 ± 3.0 ms, P = 0.01). N1, P1 and N2 latencies on the symptomatic side in patients during the cluster period (14.8 ± 2.3 ms, 20.4 ± 2.5 ms and 27.2 ± 3.0 ms, respectively) were significantly longer than those of healthy controls (13.4 ± 1.9 ms, 18.8 ± 2.4 ms and 25.0 ± 2.6 ms, respectively, P < 0.03). Outside the cluster period, N1 latencies of both sides (15.3 ± 2.8 ms symptomatic side and 15.4 ± 2.6 ms asymptomatic side) were longer compared with controls (13.4 ± 1.9 ms, P < 0.04). TSEP amplitudes and BR latencies revealed no significant differences. We conclude that abnormalities of the afferent trigeminal pathway are present in patients with cluster headache, most prominent during the cluster period, and on the symptomatic side. This seems primarily due of changes within the higher cerebral regions of the system.
Pain Sensitivity in Pericranial and Extracranial Regions
Authors: Ashina S , Jensen R , Bendtsen L
Published: June 2003

Chronic myofascial pain is very common in the general population. The pain is most frequently located in the shoulder and neck regions, and nociceptive input from these regions may play an important role for tension-type headache. The mechanisms leading to the frequent occurrence of muscle pain in the shoulder and neck regions are largely unknown. It is possible that the pain is caused by increased sensitivity of muscle nociceptors or by central sensitization induced by nociceptive input from muscle. The primary aim of the present study was to compare muscle pain sensitivity in the trapezius and anterior tibial muscles. The secondary aim was to investigate whether temporal summation, a clinical correlate of wind-up, is more pronounced in muscle than in skin and, if so, whether such a difference is more pronounced in the trapezius than in the anterior tibial region. Sixteen healthy subjects were included. Pressure-pain thresholds and electrical cutaneous and intramuscular pain thresholds were measured at standard anatomical points in the trapezius and anterior tibial regions. Temporal summation was assessed by repetitive electrical stimulation. Pressure-pain thresholds ( P = 0.005) and intramuscular electrical pain thresholds ( P = 0.006) were significantly lower in trapezius than in anterior tibial muscle. Temporal summation was present in skin and muscle of both regions ( P < 0.001). The degree of temporal summation was significantly higher in muscle than in skin in the trapezius region ( P = 0.02), but not in the anterior tibial region ( P = 0.47). In conclusion, we found that muscle pain sensitivity was higher in the trapezius than in the anterior tibial muscle. We also demonstrated that temporal summation could be induced in both muscle and skin and, importantly, that temporal summation was significantly more pronounced in muscle than in skin in the trapezius but not in the anterior tibial region. These data may help to explain why chronic muscle pain most frequently is located in the shoulder and neck regions.
Dopamine‐dependent cytotoxicity of tetrahydrobiopterin: a possible mechanism for selective neurodegeneration in Parkinson's disease
Authors: Choi Hyun Jin , Kim Seong Who , Lee So Yeon , Hwang Onyou
Published: June 2003

Parkinson's disease is a neurodegenerative disorder associated with selective loss of dopaminergic neurons in the substantia nigra. While the underlying cause of this cell death is poorly understood, oxidative stress is thought to play a role. We have previously shown that tetrahydrobiopterin (BH4), an obligatory co‐factor for tyrosine hydroxylase (TH), exerts selective toxicity on dopamine‐producing cells and that this is prevented by antioxidants. This study shows that BH4‐induced dopaminergic cell death is primarily mediated by dopamine, evidenced by findings that (i) BH4 toxicity is increased in proportion to cellular dopamine content; (ii) non‐dopaminergic cells become susceptible to BH4 upon exposure to dopamine; and (iii) depletion of dopamine attenuates BH4 toxicity in dopamine‐producing cells. BH4 causes lipid peroxidation, suggesting involvement of oxidative stress but the toxicity does not require enzymatic oxidation of dopamine. Instead, it seems to involve formation of quinone product(s) because (i) the cell death is attenuated by exposure to or induction of quinone reductase and (ii) BH4‐treated cells show increased formation of protein‐bound quinones, which is inhibited by thiol antioxidants. These data taken together suggest that the presence of both BH4 and dopamine is important in rendering dopaminergic cells vulnerable and that this involves formation of reactive dopamine quinone products.
Dopaminergic neuronal loss and motor deficits inCaenorhabditis elegansoverexpressing human α‐synuclein
Authors: Lakso Merja , Vartiainen Suvi , Moilanen Anu‐Maarit , Sirviö Jouni , Thomas James H. , Nass Richard , Blakely Randy D. , Wong Garry
Published: June 2003

Overexpression of human α‐synuclein in model systems, including cultured neurons, drosophila and mice, leads to biochemical and pathological changes that mimic synucleopathies including Parkinson's disease. We have overexpressed both wild‐type (WT) and mutant alanine53→threonine (A53T) human α‐synuclein by transgenic injection intoCaenorhabditis elegans. Motor deficits were observed when either WT or A53T α‐synuclein was overexpressed with a pan‐neuronal or motor neuron promoter. Neuronal and dendritic loss were accelerated in all three sets ofC. elegansdopaminergic neurons when human α‐synuclein was overexpressed under the control of a dopaminergic neuron or pan‐neuronal promoter, but not with a motor neuron promoter. There were no significant differences in neuronal loss between overexpressed WT and A53T forms or between worms of different ages (4 days, 10 days or 2 weeks). These results demonstrate neuronal and behavioral perturbations elicited by human α‐synuclein inC. elegansthat are dependent upon expression in specific neuron subtypes. This transgenic model inC. elegans, an invertebrate organism with excellent experimental resources for further genetic manipulation, may help facilitate dissection of pathophysiologic mechanisms of various synucleopathies.
Differential effect of nitric oxide on glutathione metabolism and mitochondrial function in astrocytes and neurones: implications for neuroprotection/neurodegeneration?
Authors: Gegg M. E. , Beltran B. , Salas‐Pino S. , Bolanos J. P. , Clark J. B. , Moncada S. , Heales S. J. R.
Published: June 2003

Primary culture rat astrocytes exposed to the long acting nitric oxide donor (Z)‐1‐[2‐aminoethyl)‐N‐(2‐ammonioethyl)amino]diazen‐1‐ium‐1,2‐diolate (DETA‐NO) for 24 h approximately double their concentration of glutathione (GSH) and show no sign of cell death. In contrast, GSH was depleted by 48%, and significant loss of mitochondrial respiratory chain complex activity and cell death were observed in primary culture rat neurones subjected to DETA‐NO for 18 h. Northern blot analysis suggested that mRNA amounts of both subunits of glutamate‐cysteine ligase (GCL), the rate‐limiting enzyme in GSH synthesis, were elevated in astrocytes following nitric oxide (NO) exposure. This correlated with an increase in astrocytic GCL activity. Neurones on the other hand did not exhibit increased GCL activity when exposed to NO. In addition, the rate of GSH efflux was doubled and γ‐glutamyltranspeptidase (γ‐GT) activity was increased by 42% in astrocytes treated with NO for 24 h. These results suggest that astrocytes, but not neurones, up‐regulate GSH synthesis as a defence mechanism against excess NO. It is possible that the increased rate of GSH release and activity of γ‐GT in astrocytes may have important implications for neuroprotection in vivo by optimizing the supply of GSH precursors to neurones in close proximity.
Synergistic inhibitory effect of ascorbic acid and acetylsalicylic acid on prostaglandin E2 release in primary rat microglia
Authors: Fiebich Bernd L. , Lieb Klaus , Kammerer Norbert , Hüll Michael
Published: June 2003

Ascorbic acid (vitamin C) has been suggested to protect cerebral tissue in a variety of pathophysiological situations such as head trauma, ischemia or Alzheimer's disease. Most of these protective actions have been attributed to the antioxidative capacity of ascorbic acid. Besides the presence of elevated levels of oxygen radicals, prostaglandins produced by neurones and microglial cells seem to play an important role in prolonged tissue damage. We investigated whether ascorbic acid alone inhibits prostaglandin E2 (PGE2) synthesis and may augment the inhibitory effect of acetylsalicylic acid on prostaglandin synthesis. Ascorbic acid dose‐dependently inhibited PGE2 synthesis in lipopolysaccharide‐treated primary rat microglial cells (IC50 = 3.70 µm). In combination with acetylsalicylic acid (IC50 = 1.85 µm), ascorbic acid augmented the inhibitory effect of acetylsalicylic acid on PGE2 synthesis (IC50 = 0.25 µm in combination with 100 µm ascorbic acid). Ascorbic acid alone or in combination with acetylsalicylic acid did not inhibit cyclooxygenase‐2 (COX‐2) protein synthesis but inhibited COX‐2 enzyme activity. Our results show that ascorbic acid and acetylsalicylic acid act synergistically in inhibiting PGE2 synthesis, which may help to explain a possible protective effect of ascorbic acid in various brain diseases.
Exaggerated effect of fluvoxamine in heterozygote serotonin transporter knockout mice
Authors: Montañez Sylvia , Owens W. Anthony , Gould Georgianna G. , Murphy Dennis L. , Daws Lynette C.
Published: June 2003

Clearance rates for serotonin (5‐HT) in heterozygote (+/–) and homozygote (–/–) serotonin transporter (5‐HTT) knockout (KO) mice have not been determined in vivo. Moreover, the effect of selective serotonin reuptake inhibitors (SSRIs) on 5‐HT clearance in these mice has not been examined. In this study, the rate of clearance of exogenously applied 5‐HT was measured in the CA3 region of the hippocampus of anesthetized mice using high‐speed chronoamperometry. Compared with wild‐type mice, the maximal rate of 5‐HT clearance from extracellular fluid (ECF) was decreased in heterozygotes and more markedly so in KO mice. Heterozygote mice were more sensitive to the 5‐HT uptake inhibitor, fluvoxamine, resulting in longer clearance times for 5‐HT than in wild‐type mice; as expected, the KO mice were completely unresponsive to fluvoxamine. There were no associated changes in norepinephrine transporter density, nor was there an effect of the norepinephrine uptake inhibitor, desipramine, on 5‐HT clearance in any genotype. Thus, adaptive changes in the norepinephrine transport system do not occur in the CA3 region of hippocampus as a consequence of 5‐HTT KO. These data highlight the potential of the heterozygote 5‐HTT mutant mice to model the dynamic in vivo consequences of the human 5‐HTT polymorphism.
Top‐down or Bottom‐up Effects by Fish: Issues of Concern in Biomanipulation of Lakes
Authors: Horppila Jukka , Peltonen Heikki , Malinen Tommi , Luokkanen Eira , Kairesalo Timo
Published: June 2003

A large‐scale biomanipulation trial was carried out on Lake Vesijärvi in Finland during 1989–1993. Following the mass removal of coarse fish the biomass of cyanobacteria collapsed from 1.4 g/m−3 to below 0.4 g/m−3, while total phosphorus concentration declined from 45 μg/L to 30 μg/L. No relevant changes in zooplankton communities were observed. The results suggest that the success of food web manipulation as a tool for lake restoration is not necessarily dependent on the grazing rate of zooplankton. The effects of reduced fish‐mediated internal loading and recycling of nutrients are in many cases stronger than those of reduced planktivory. Alternative stable states of water quality may also exist in lakes not covered by macrophytes, owing to the changes in the behavior of fish stocks. Year‐to‐year variation in the littoral zone may cause large oscillations in lake ecosystems—for example, through the recruitment of fish. In addition, the nutrients translocated by fish from the littoral zone may affect the nutrient dynamics of the pelagial plankton community. In terms of phytoplankton species composition and the ratio of phosphorus to chlorophyll a, the water quality in Lake Vesijärvi has improved in a stepwise fashion within the last 10 years. This is probably due to the fact that the five‐year mass removal of fish in Enonselkä fulfilled the requirement of sustained management of fish stocks in order to maintain nonequilibrial conditions between alternate stable states. The prediction of the water quality development is obscured, however, by spatial and temporal within‐lake variation, which sets high requirements for sampling programs.
Seed Inputs to Microsite Patch Recovery on Two Tropandean Landslides in Ecuador
Authors: Myster Randall W. , Sarmiento Fausto O.
Published: June 2003

To understand landslide regeneration and provide information necessary for restoration, we sampled seed rain, seed pool, and plant cover on two Ecuadorian landslides. We trapped 1304 seeds and found that, while most seeds were in the family Asteraceae, there was substantial variation in seed rain among plant families. Four hundred and seventy‐five seedlings emerged from soil samples, including nonvascular and vascular families; again, species in Asteraceae dominated, with species in Piperaceae also very common. Plant cover, consisting of members of four fern families and 20 vascular plant families—with species in Asteraceae, Melastomataceae and Poaceae most common—was scored as a percentage of the total plot area. Principal components analysis (PCA) showed that, for all three of these plant life stages (seed rain, seed‐propagule pool, plant cover), spatial variation was dominated by differences between the two landslides rather than within‐landslide plot differences. PCA also showed that plots separated best on axes defined by the families Cecropiaceae, Urticaceae, Melastomataceae, Papilionaceae, Asteraceae, and Araceae with clumping of families in PCA space suggesting common successional strategies. Another multivariate technique, canonical correspondence analysis (CCA), showed that the combined seed rain and seed pool data could predict the percent cover of the family Verbenaceae and that the current plant cover families could predict Asteraceae seeds and seedlings. Finally, we use our past and present landslide data, along with multivariate modeling results, to suggest strategies for successful landslide restoration.
Migraine in Twins Raised Together and Apart
Authors: Ziegler Dewey K. , Hur Yoon‐Mi , Bouchard Thomas J. , Hassanein Ruth S. , Barter Ruth
Published: June 2003

History of headache and migraine diagnosed by structured interview utilizing International Headache Society criteria was obtained in two samples of female twin pairs—154 raised together and 43 raised apart since infancy. Zygosity was determined by standard methods. Probandwise concordance rates were determined. Assuming that liability to migraine has a multifactorial etiology involving a number of genetic and environmental risk factors acting additively, tetrachoric correlations in the four groups of twins (monozygotic raised together, monozygotic raised apart, dizygotic raised together, and dizygotic raised apart) were then calculated. The genetic and environmental influences in the liability to migraine were estimated using biometrical model‐fitting methods.

Tetrachoric correlations for migraine were consistently higher in monozygotic than in dizygotic twins, for both reared together and reared apart samples, with a heritability estimate of 52%. Model fitting also suggested that approximately 50% of the variance in liability to migraine was attributable to genetic factors with nonshared environmental factors and measurement errors responsible for the remaining variance.
Quality of Life and Productivity in Nurses Reporting Migraine
Authors: Durham Carol F. , Alden Kathy R. , Dalton Jo Ann , Carlson John , Miller David W. , Englebardt Sheila P. , Neelon Virginia J.
Published: June 2003

A random sample survey was conducted to determine the prevalence of migraine in nurses and to study its effect on quality of life and productivity. Of the 10 000 nurses sampled, 2949 returned the questionnaire for a response rate of 29.5%. The majority (99%) of respondents were employed and worked in hospitals (60%). According to the International Headache Society (IHS) criteria, 17% of the sample (n=495) were classified as having migraine. An additional 25% (n=750) suffered severe headaches but did not meet IHS criteria for migraine, and the remaining 58% (n=1704) were classified as not having either migraine or severe headaches. The migraineurs had significantly reduced work productivity and quality of life compared to both the severe headache and the nonmigraine nonsevere headache groups. This study will increase awareness and sensitivity of the profession to its colleagues who are migraine sufferers.
Pharmacokinetics and Pharmacodynamics of Avitriptan in Patients With Migraine After Oral Dosing
Authors: Cutler Neal R. , Salazar Daniel E. , Jhee Stanford S. , Fulmor I. Edgar , Ford Neville , Smith Robert A. , Sramek John J.
Published: June 2003

Avitriptan (BMS‐180048) is a 5‐HT1‐like receptor agonist for the treatment of migraine. This double‐blind, placebo‐controlled, randomized, parallel‐group study evaluated the pharmacokinetics, safety, and preliminary efficacy of avitriptan in patients with migraine during migrainous and pain‐free states. Patients met the IHS criteria for migraine with or without aura and suffered one to six migraines per month for at least 1 year. Patients in a clinic experiencing a migraine headache received avitriptan 75 mg, 150 mg, or 200 mg or matching placebo capsules. Blood samples were obtained before and 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 5, and 6 hours after dosing. Headache intensity was rated before and up to 6 hours after dosing. Seven to 30 days after the inclinic treatment, patients returned in a pain‐free state for the same study medication. All pharmacokinetic and safety measures were repeated. Forty‐eight patients (9 men and 39 women) participated. Peak plasma concentrations of avitriptan were achieved 1 to 2 hours following dosing in migraine and pain‐free states for all doses. The pharmacokinetics of avitriptan were proportional to dose during a migraine attack over the 75‐ to 200‐mg dose range. The 150‐ and 200‐mg doses of avitriptan demonstrated a greater decrease in headache intensity scores at 2 hours postdose. The most common adverse event was paresthesia. Thus, avitriptan was rapidly absorbed, well tolerated, and demonstrated preliminary efficacy in this population.
Amitriptyline Is Effective in Chronic But Not in Episodic Tension‐Type Headache: Pathogenetic Implications
Authors: Cerbo Rossana , Barbanti Piero , Fabbrini Giovanni , Pascali Maria Paola , Catarci Teresa
Published: June 2003

The tricyclic antidepressant amitriptyline, is an effective drug for the treatment of chronic tension‐type headache and for other chronic pain syndromes, but it is also effective in the prophylaxis of an episodic type of headache such as migraine. However, its efficacy in episodic tension‐type headache has not yet been clarified. We compared the efficacy of amitriptyline (25 mg/day) in 82 nondepressed patients with either chronic or episodic tension‐type headache in an open‐label study. Amitriptyline significantly reduced (P<0.05) frequency and duration of headache as well as analgesic consumption in chronic, but not in episodic, tension‐type headache. Further placebo‐controlled trials, possibly with higher doses of amitriptyline, might confirm if the different pattern of response to amitriptyline can be explained in terms of different involvement of central nociception and of peripheral myofascial factors in the chronic and in the episodic forms of tension‐type headache.
Platelet Antibodies in Patients With Migraine
Authors: Schabet Martin , Hummler Markus , Schepelmann Karsten , Schnaidt Martina
Published: June 2003

The reported decrease of platelet serotonin receptors in patients with migraine could be due to an autoimmune reaction. We, therefore, examined sera from 42 migraineurs without aura, 26 migraineurs with aura, and 107 headache‐free blood donors for platelet‐reactive antibodies using the platelet adhesion immunofluorescence test, the NIH‐lymphocytotoxicity test, and the monoclonal antibody‐specific immobilization of platelet antigens test. IgG antibodies against non‐HLA class I platelet antigens were found in 9.5% of patients with migraine without aura, 7.6% of patients with migraine with aura, and in 7.5% of controls; IgM antibodies were found in 11.9% of patients with migraine without aura, in 30.8% of patients with migraine with aura, and in 13.1% of controls. Most antibodies ware directed against glycoprotein complexes IIb‐IIIa (fibrinogen receptor) or IB‐IX (thrombin receptor). Two patients with migraine without aura but no patient with migraine with aura nor any control subject had IgG antibodies of unknown specificity. One patient (2.4%) with migraine without aura and two patients (7.7%) with migraine with aura, as well as 2 controls (1.9%) had IgM antibodies not further specified. The differences in frequency of platelet antibodies of known or unknown specificity in patients with migraine without aura and migraine with aura and controls were not statistically significant. Therefore, our data do not support the hypothesis of a pathophysiologically relevant autoimmune reaction against platelet serotonin receptors in the majority of patients with migraine. We can not exclude the occurrence of antibodies against neuron‐specific serotonin receptors.
Anticephalgic Photoprotective Premeditated Mask. A Report of a Successful Double‐Blind Placebo‐Controlled Study of a New Treatment for Headaches With Associated Frontalis Pain and Photophobia
Authors: Hyson Morton I.
Published: June 2003

This study was performed to determine the efficacy of an anticephalgic photoprotective premedicated mask in the treatment of migraine and/or tension‐type headaches. There were 54 patients. They were given masks and numbered bottles of topical medication containing either salicin or placebo. The patients were instructed to apply the medication to their frontalis region in the event they should suffer a headache, apply a photoprotective mask, and lie down. Furthermore, they were instructed to take their usual oral or parenteral medications, if required, for relief of the headache. They subsequently filled out forms rating the degree of relief which they attributed to the topical medications and the masks using a 0 to 10 scale. They were also simply asked if this form of treatment helped or not.

Seven of the 20 patients receiving placebo stated the medication and mask helped. The placebo group rated the treatment an average of 4.31 on a 0 to 10 scale. Twenty‐eight of 34 patients receiving salicin stated it was effective. The salicin group rated it 7.42 on a 0 to 10 scale (P<0.001). The majority of the salicin patients stated the duration of their headaches was significantly reduced, as was their need for analgesic and/or narcotic medications.

This study demonstrates a significant difference between placebo and salicin in association with the photoprotective mask in treating migraines and/or tension‐type headaches with associated frontalis pain and photophobia.
Prevalence of Frequent Headache in a Population Sample
Authors: Scher Ann I. , Stewart Walter F. , Liberman Joshua , Lipton Richard B.
Published: June 2003

Purpose.—Patients with daily or near‐daily headaches are commonly seen in neurology practices and in headache subspecialty centers, but there is little information on the prevalence of this condition in the general population. We present the first US‐based study describing the prevalence and characteristics of frequent headache in the general population.

Methods.—In Baltimore County, Maryland, 13 343 individuals 18 to 65 years of age were selected by random‐digit dialing and interviewed by telephone about their headaches. Subjects reporting 180 or more headaches per year were classified as having frequent headache. Three mutually exclusive subtypes of frequent headache were identified: frequent headache with migrainous features, chronic tension‐type headache, and unclassified frequent headache.

Results.—The overall prevalence of frequent headache was 4.1% (5.0% female, 2.8% male; 1.8:1 female to male ratio). Frequent headache was 33% more common in Caucasians (4.4%) than in African Americans (3.3%). In both males and females, prevalence was highest in the lowest educational category. Among frequent headache sufferers, more than half (52% female, 56% male) met criteria for chronic tension‐type headache, almost one third (33% female, 25% male) met criteria for frequent headache with migrainous features, and the remainder (15% female, 19% male) were unclassified. Overall, 30% of female and 25% of male frequent headache sufferers met International Headache Society (IHS) criteria for migraine (with or without aura).

Conclusions.—Frequent headache is common in the general population and is more prevalent in Caucasians and in those with less than a high school education. Chronic tension‐type headache is more common than frequent headache with migrainous features, though the latter is more disabling. Although more common in females than males, the female preponderance of frequent headache is less marked than in migraine. The sex ratio varies by frequent headache subtype.
Comparison of Butorphanol Nasal Spray and Fiorinal With Codeine in the Treatment of Migraine
Authors: Goldstein Jerome , Gawel Marek J. , Winner Paul , Diamond Seymour , Reich Linda , Davidson Wendy J. , Sussman Neil M.
Published: June 2003

Butorphanol tartrate is a synthetic mixed agonist‐antagonist opioid analgesic. Its transnasal dosage form, which may be self‐administered when the use of an opioid analgesic is appropriate, was previously shown to provide rapid relief of migraine pain. In this double‐blind, parallel‐group, outpatient study, we compared butorphanol nasal spray 1 mg followed in 1 hour by an optional second 1‐mg dose with the orally administered analgesic, Fiorinal with Codeine (one capsule containing butalbital 50 mg, caffeine 40 mg, aspirin 325 mg, and codeine phosphate 30 mg). Patients (N=321) were assigned by randomization to one of two treatment groups (butorphanol or Fiorinal with Codeine) and instructed to self‐administer medication when migraine pain reached an intensity of moderate or severe and to record study‐related events in a diary for 24 hours posttreatment. Efficacy analyses were performed on data from 275 patients who took study medication and returned a patient diary; 136 in the butorphanol group and 139 in the Fiorinal with Codeine group.

During the first 2 hours after treatment, butorphanol was more effective than Fiorinal with Codeine in treating migraine pain as measured by pain intensity difference scores, percentage of responders (pain decreased to mild or none), percentage of pain‐free patients, and degree of pain relief, with a more rapid time to onset of 15 minutes. A similar percentage of patients in the two groups used rescue medication during the first 4 hours, after which more butorphanol‐treated than Fiorinal with Codeine‐treated patients used rescue medication. Butorphanol patients had more side effects, less improvement in digestive symptoms, and less improvement in functional ability than Fiorinal with Codeine patients.
Development of Chronic Daily Headache: A Clinical Study
Authors: Spierings Egilius L.H. , Schroevers Maya , Honkoop Peter C. , Sorbi Marjolijn
Published: June 2003

We studied the development of chronic daily headache in 258 headache practice patients, 50 men and 208 women. Chronic daily headache was defined as headaches occurring at least 5 days per week for at least 1 year.

Twenty‐two percent of the patients had daily headaches from the onset, and 78% initially experienced intermittent headaches. Of the patients with initially intermittent headaches, 19% experienced an abrupt transition into daily headaches and 81% a gradual one. The distribution of the age of daily headache onset was the same in the patients with daily headaches from the onset and in those with initially intermittent headaches but with abrupt transition into daily headaches. The distribution of the circumstances of daily headache onset was also the same in the groups. The most common circumstance of abrupt onset of daily headaches was head, neck, or back injury, in 61% caused by a motor vehicle accident. In the patients with initially intermittent headaches but with gradual transition into daily headaches, the transition took an average of 10.7 years.
Cyclic Vertigo With Predictable Recurrence
Authors: Lobel Danielle , Eviatar Lydia
Published: June 2003

The long‐term follow‐up of six children with “cyclic vertigo,” that has recurred for years, at strikingly predictable intervals, is presented. Vertigo and photophobia, lasting several hours, start early in the morning, daily for several consecutive days, and recur at predictable intervals without evidence of long‐term neurological deficits. The interval between events increases with age. Diagnostic criteria are suggested. Cyclic vertigo may be a migraine equivalent caused by periodic derangement of the mechanisms controlling the generation of circadian rhythms.
Significance of Migrainous Features in Cluster Headache: Divalproex Responsiveness
Authors: Wheeler Steve D.
Published: June 2003

Two patients with cluster headache and prominent migrainous features are described and a shared migraine and cluster headache pathophysiology is discussed. Both patients failed routine cluster headache pharmacotherapy, one failed multiple operative interventions; however, both remitted on divalproex. It is suggested that migrainous features be assessed in cluster headache and divalproex initiated before pursuing invasive procedures.
Two-body polyelectrolyte-mediated bridging interactions
Authors: Podgornik Rudi
Published: June 2003

We investigate theoretically polyelectrolyte bridging interactions on the two-body level. The model system is composed of two macroions with two oppositely charged flexible chains. The electrostatic interactions are treated on the Debye–Hückel level. The formal level of the theory is provided by the Feynman–Kleinert variational method generalized to include also self-interactions between polyelectrolyte segments. The variational equations are shown to exhibit two solution branches corresponding to strong and weak coupling, whereas conformations of the chain can be described as weakly or strongly paired. We investigate the effective pair interaction between the macroions in the parameter space and comment on the relevance of the calculation for bridging interactions in experimental context.