bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclic voles, prey switching in red fox, and roe deer dynamics – a test of the alternative prey hypothesis
Authors: Kjellander Petter , Nordström Jonas
Published: December 2004

Medium‐sized predators sometimes switch to alternative prey species as their main prey declines. Our objective of this study was to test the alternative prey hypothesis for a medium sized predator (red fox, Vulpes vulpes), a small cyclically fluctuating main prey (microtine voles) and larger alternative prey (roe deer fawns, Capreolus capreolus). We used long‐term time series (28 years) on voles, red fox and roe deer from the Grimsö Wildlife Research Area (59°40′N, 15°25′E) in south‐central Sweden to investigate interspecific relationships in the annual fluctuations in numbers of the studied species. Annual variation in number of roe deer fawns in autumn was significantly and positively related to vole density and significantly and negatively related to the number of fox litters in the previous year. In years of high vole density, predation on roe deer fawns was small, but in years of low vole density predation was more severe. The time lag between number of fox litters and predation on fawns was due to the time lag in functional response of red fox in relation to voles. This study demonstrates for the first time that the alternative prey hypothesis is applicable to the system red fox, voles and roe deer fawns.
Delayed timing as a strategy to avoid nest‐site competition: testing a model using data from starlings and flickers
Authors: Wiebe Karen L.
Published: December 2004

European starlings (Sturnus vulgaris) introduced to North America compete with native cavity‐nesting birds for nest sites. I examined whether natural selection could favour a strategy of delayed nesting in a population of northern flickers (Colaptes auratus), a native woodpecker, to reduce overlap in breeding phenology with starling competitors. I developed a mathematical model based on reproductive parameters for a population of flickers from central British Columbia, Canada. On average, 7% of flicker nests each year were usurped by starlings; daily probabilities of takeover declined through the season but were relatively low (1–2%). Flickers laid between 3 and 13 eggs and there was a negative correlation between clutch size and date. The probability of renesting after nest failure also declined during the season, but renesting intervals (2–19 days) were not associated with female age, or stage of nest loss. The model suggested that costs of delaying reproduction would outweigh benefits of an early start except when the probability of nest usurpation is very high (>75%) early in the season and declines rapidly through the summer. Thus, early laying dates should be favoured especially in northern latitudes where breeding seasons are short.
The influence of varying spatial heterogeneity on the refuge model for coexistence of specialist parasitoid assemblages
Authors: Porter Eric E. , Hawkins Bradford A.
Published: December 2004

Models of host–parasitoid dynamics often assume constant levels of spatial heterogeneity in parasitoid attack rate, which tends to stabilize the interactions. Recently, authors have questioned this assumption and shown that outcomes of simple host–parasitoid models change if spatial heterogeneity is allowed to vary with parasitoid density. Here, we allow spatial heterogeneity to vary with either parasitoid density or percent parasitism in a model designed to explain specialist parasitoid coexistence on insect hosts with various levels of refuge. By examining this model we can evaluate the effect of varying spatial heterogeneity on a more complex model in which spatial heterogeneity is not considered the primary determinant of persistence. By modeling communities with one host and two parasitoid species, we show that the probability of species persistence for the competitively inferior parasitoid depends on the assumed relationship between spatial heterogeneity and both parasitoid density and percent parasitism. The probability of parasitoid coexistence is generally lower when spatial heterogeneity varies with parasitoid demographics. We conclude that the conditions for which host refuge promote specialist parasitoid coexistence are less common that proposed by the original model. Finally, we compared a model in which spatial heterogeneity varies with percent parasitism to data from laboratory trials and find a reasonable fit. We conclude that the change in spatial heterogeneity strongly influenced the outcome of the laboratory trials, and we suggest more research is necessary before researchers can assume constant spatial heterogeneity in future models.
Induced responses of nestling great tits reduce hen flea reproduction
Authors: Walker Mirjam , Steiner Susanne , Brinkhof Martin W. G. , Richner Heinz
Published: December 2004

The dynamics of host–parasite interactions depend to a large extent on the effect of host responses on parasite fitness. Exposure to parasites may induce behavioural or physiological responses in hosts that may reduce the subsequent survival or reproductive output of the parasite. Neonate hosts may further directly obtain immunologically active substances from their mother, for instance via milk in mammals or egg yolk in birds. However, the relative importance of maternally‐derived and self‐generated responses in inducing parasite resistance is poorly understood, especially in free‐living vertebrates. Here we investigate the complementary effect of experimentally induced maternal and neonate responses in great tit (Parus major) hosts on the reproductive success of their common ectoparasite, the hen flea (Ceratophyllus gallinae). In the laboratory we measured the number of eggs and larvae produced by individual flea females collected from host nests. In addition, the total number of larvae produced by an experimentally set number of flea females in the host's nestbox was assessed under field conditions. There was no indication of maternally‐transferred parasite resistance, since exposing the mother to fleas during the laying period did not affect the reproductive rate of fleas exploiting her offspring early or late in the nestling cycle. Independent of the maternal treatment, exposure of neonates to fleas early in the nestling period reduced the reproductive output of fleas late in the nestling cycle. The effect of the induced nestling response was seasonal, reducing flea reproduction in nests of early‐breeding hosts but not in nests of late‐breeding ones. Larvae production in the nestbox and in the laboratory was positively correlated, but under natural conditions the neonate response did not affect the size of the flea larvae population. Our results indicate induced responses as a means by which neonate avian hosts resist ectoparasites. Other factors, such as the environmental temperature and density‐dependent larval competition, may be more important in determining the size of the future parasite populations.
Species richness along multiple gradients: testing a general multivariate model in oak savannas
Authors: Weiher Evan
Published: December 2004

A confirmatory structural equation model was built in order to test the generality of Grace and Pugesek's model of species richness. A main feature of their model was that light reaching the soil surface had the strongest effects on species richness, and that disturbance and biomass effects were largely indirect via effects on light. Their model was not confirmed for the understory vegetation of floodplain oak savannas and a new model had numerous fundamental differences. Disturbance history had the strongest direct effects on richness and these were independent of biomass effects. Richness was maximal at intermediate disturbance and biomass. Bivariate relationships between soil quality and species density were very weak because soil quality simultaneously had negative direct effects and positive indirect effects (through biomass), such that the total effect of soil was negligible. This provides an example of how structural modeling can provide insights that are not possible with other numerical methods. The complex effects of soils support recent findings that some soil components tend to increase richness via a species pool effect while other components tend to reduce richness via biotic interactions. The effects of light were not significant, but canopy trees had weak, positive effects, and this contradicts other structural models which have generally shown that shading reduces species richness. Here, species richness increases with shade presumably because of species pool effects, whereby the species pool increases by including prairie, savanna, and some woodland species and indirectly by reducing dominance by warm‐season grasses. The results have implications for management because of the overall importance of disturbance history, however the majority of the variation in richness was left unexplained and this suggests other factors such as dispersal limitation, soil fungi, and historical effects may be of overriding importance in these oak savannas.
Modes of speciation and the lifespans of species under neutrality: a response to the comment of Robert E. Ricklefs
Authors: Hubbell S.P.
Published: December 2004

Ricklefs (2003) has presented a thoughtful critique of the two modes of speciation discussed in my recent book (Hubbell 2001a). His main point is that under point mutation speciation, a plethora of species is produced with extremely short lifespans, whereas under random fission speciation, lifespans are too long, particularly in large metacommunities. The issue is easily resolved if one regards point mutation speciation and random fission speciation as the theoretical extremes of a speciation continuum. The mean lifespan of a species in the theory depends upon the size of the species population at its origination. If initial population sizes are fairly small, but not as small as the extreme of individual‐founded lineages as under point mutation, then intermediate distributions of species lifespans are obtained. To examine this further, I consider a third model of speciation that I call “peripheral isolate speciation.” There should be a signature of peripheral isolate speciation in the distribution of metacommunity relative species abundance, just as there is in the case of point mutation speciation and random fission speciation. Other points made by Ricklefs and several others are addressed in the body of the text.
Parasites and size‐assortative schooling in three‐spined sticklebacks
Authors: Barber Iain
Published: December 2004

Recent field studies carried out in lacustrine environments have suggested that fish schools may be assorted with respect to parasite infections, but the generality and strength of parasite‐assortative schooling in fish is unclear. In this study, data are presented on the body size and externally visible macroparasite load of 366 individual three‐spined sticklebacksGasterosteus aculeatusL. (Gasterosteidae, Teleostei) from six naturally formed schools captured in the Gullmarsfjord on the west coast of Sweden. Length–frequency analysis suggested that two separate year classes (presumed 0+ and 1+) were represented in the sample. Individual schools were assorted by body size, and contained largely fish of a single year class. The number of fish in the school was negatively related to median body size of members. Probability of infection increased significantly with fish length for two parasites (Cryptocotyle lingua(Trematoda) andGlugea anomala(Microsporidia)), and marginally for a third (chalimus larvae ofCaligussp. (Copepoda)). After correcting for body‐size effects, the proportion of school members infected withC. linguaandG. anomaladid not differ significantly from a model of random assortment by infection status. However, two of the six schools were found to have significantly more, or significantly fewer, members infected withCaligussp. chalimus larvae than predicted by the random model. Significant inter‐school differences in the intensity ofC. linguainfection were also detected, but these resulted from the combined effects of size‐assortment and a strong correlation between body size and infection intensity. The results of this study provide only limited support for the existence of active parasite‐assortative schooling in marine sticklebacks, and are discussed in relation to recent studies of parasite assortment amongst host fish in other ecosystems.
Effect of Acute and Chronic Lead Exposure on Apomorphine‐Induced Sniffing in Rats
Authors: Fazli‐Tabaei Soheila , Fahim Mohammad , Zarrindast Mohammad‐Reza
Published: December 2004

Abstract: Sniffing is a behaviour which can be induced by dopamine D1/D2 receptor agonists. In order to test the effect of chronic lead exposure on dopamine receptor subtypes, we studied the effects of acute and chronic lead exposure on sniffing induced by apomorphine, a dopamine receptor agonist. Intraperitoneal injection of the dopaminergic receptor agonist, apomorphine (0.25–1 mg/kg), induced dose‐dependent the sniffing behaviour in rats. Acute administration of lead acetate (50, 100 and 200 mg/kg) decreased the apomorphine‐induced sniffing. Chronic lead (0.25%) exposure also decreased the apomophine response. Dopamine D1 or D2 receptor antagonists reduced the apomorphine effect. Lead exposure could not potentiate the blockade induced by the dopamine receptor antagonists. It is concluded that the response of lead is not mediated by alteration of dopamine receptors.
Effect of Iron Treatment on Nickel Absorption and Gene Expression of the Divalent Metal Transporter (DMT1) by Human Intestinal Caco‐2 Cells
Authors: Tallkvist Jonas , Bowlus Christopher L. , Lönnerdal Bo
Published: December 2004

Abstract: Divalent Metal Transporter 1 (DMT1) is a transmembrane transporter located at the apical membrane of enterocytes and implicated in the duodenal uptake of iron. Results from expression experiments in Xenopus oocytes indicate that DMT1 can mediate transport of a wide range of divalent metals other than iron. The aim of the present study was to examine the effect of iron treatment on the uptake and transepithelial movement of 63Ni and to correlate that to DMT1 messenger RNA (mRNA) levels in human intestinal Caco‐2 cells. Twenty‐one days after confluent Caco‐2 cell monolayers were treated for 1 or 3 days with medium supplemented with Fe(NTA)2 or control medium and 63Ni transport and DMT1 gene expression were measured at both time points. Functional effects of the iron treatment were assessed by examining uptake and transepithelial movement of 59Fe. Iron treatment resulted in decreased DMT1 gene expression which correlated well with the uptake of 59Fe and 63Ni into fully differentiated Caco‐2 cells. This indicates that DMT1 is responsible for the apical transport of these metals in the intestinal epithelium and suggests that adequate iron intake and status will limit nickel absorption.
Changes in Brain Serotonin Turnover, Body and Head Shakes in Kainic Acid‐Treated Rats
Authors: Osorio‐Rico Laura , Mancera‐Flores Mayra , Ríos Camilo
Published: December 2004

Abstract: Kainic acid induces seizures and neurotoxicity in rats, produces changes in brain serotonin (5‐HT), dopamine and noradrenaline metabolites among other changes in neurotransmitters. In this work, we investigated the changes in 5‐HT turnover in brain regions from 84 rats intraperitoneally injected with kainic acid and a specific behavioural change, the body and head shakes, exerted by this neurotoxin in the presence of 5‐HT receptor antagonists. Kainic acid produced an increase in 5‐hydroxyindoleacetic acid levels in frontal cortex (212%; 180%), striatum (177%; 116%), amygdala (202%; 337%) and hippocampus (43%; 70 %) at 2 and 24 hr as compared with controls, respectively. Serotonin turnover was increased in amygdala (157%) and frontal cortex (169%) at 2 hr; whereas 24 hr after kainic acid administration, increases were observed in amygdala (207%), and frontal cortex (178%). Kainic acid also produced an increase in the frequency of head and body shakes when administered alone or together with pargyline, a monoamine oxidase inhibitor; whereas the administration of 5‐HT receptor antagonists such as ketanserin and methiothepin, decreased this behaviour 54% and 50% as compared with kainic acid alone, respectively. These results suggest an active participation of 5‐HT neurotransmission on the excitotoxic action of kainic acid in the brain.
Comparative Actions of Diazepam and Other Phosphodiesterase Inhibitors on the Effects of Noradrenaline in Rat Myocardium
Authors: Juan‐Fita María J. , Vargas María L. , Hernández Jesús
Published: December 2004

Abstract: Diazepam inhibits different isoforms of the enzyme cyclic nucleotide phosphodiesterase and also potentiates the inotropic effect of endogenous catecholamines in rat heart. In the present study we have examined whether this late effect is the consequence of inhibition of a phosphodiesterase subtype or whether inhibition of several phosphodiesterase subtypes is involved. We compared the effect of diazepam with that of the selective inhibitors of phosphodiesterase1 (MIMX), phosphodiesterase2 (EHNA), phosphodiesterase3 (milrinone) and phosphodiesterase4 (rolipram) on the inotropic effect of noradrenaline in rat ventricle. Both rolipram or diazepam were equipotent and more effective than milrinone in potentiating the inotropic effect of noradrenaline whereas EHNA and MIMX had no effect. The results suggest that the diazepam induced potentiation of the contractile effect of noradrenaline is due principally to inhibition of phosphodiesterase4 isoenzyme activity.
Ninety‐six points of light: phototherapy practices of members of The Photomedicine Society
Authors: Evans Colby C. , Cruz Ponciano D.
Published: December 2004

Background: Phototherapy is an effective and relatively safe treatment for many skin diseases. Recent concern has focused on an apparent decline in phototherapy usage in the US.

Objective: To determine the current state of phototherapy as practiced globally.

Methods: Cross‐sectional survey of members of the Photomedicine Society.

Results: Data derived from responses of 96 members showed all to have been in practice for more than five years, providing phototherapy within two years of completing residency. Usage of narrow‐band ultraviolet B, ultraviolet A‐1 (UVA‐1), bath‐psoralens plus UVA, and photodynamic therapy was markedly greater among phototherapists in Europe compared to their counterparts in North America and Asia.

Conclusions: Worldwide, there are fewer younger dermatologists who incorporate phototherapy in their practices. European phototherapists have led the world in usage of the newer phototherapy modalities.
Uniformity of sunscreen product application: a problem in testing, a problem for consumers
Authors: Lott Dennis L. , Stanfield Joseph , Sayre Robert M. , Dowdy John C.
Published: December 2004

Background/Aims: Testing of sunscreen products requires application of uniform films of product of defined thickness to test volunteers. In spite of the seeming importance of product application to defining sunscreen efficacy, there have been few studies determining how well uniformity is achieved. The purpose of this work was to evaluate the uniformity of sunscreen products of different sun protection factors (SPFs) and vehicles on a variety of substrates by in vitro testing techniques. The results of a variety of testing strategies are reported.

Methods: Five commercial sunscreen products of labelled SPF 4–50 were tested using a variety of substrates: Transpore® Tape, Vitro‐Skin™, and lambskin condom. Two experienced sunscreen testers applied the products. In vitro SPFs were determined using an Optometric 290 analyser or an Optronic Laboratories OL754 spectroradiometer configured for this application.

Results: SPFs for several locations on each film applied to a substrate were determined and the mean SPF and RSD percentage of the mean calculated. For all substrates and testing techniques the average RSD percentage was 18.6, with a range of 10–40%.

Conclusion: The expected uncertainty of SPF due to product application non‐uniformity is 20% when applied under optimal test conditions. Clearly SPF tests reported by different laboratories must exhibit significant variability, because of product application non‐uniformity.
The influence of pre‐irradiation on the predictability of in vivo UVA protection with a new in vitro method
Authors: Wendel V. , Klette E. , Wittern K.‐P. , Gers‐Barlag H.
Published: December 2004

Background/Purpose: UVA protection of sunscreen formulations is becoming increasingly important especially because of recent investigations on the long‐term skin damage associated with UVA light. The development of a new in vitro method to measure UVA protection performance made it possible to predict reliably the in vivo UVA protection performance of representative sunscreen formulations found presently in the European and US market (1). This study was performed in order to determine the applicability of the method developed by Wendel et al. (1) to photostable and photolabile filter combinations and in order to measure the influence of sample pre‐irradiation on predicting the in vivo performance. This was done by subjecting six photostable and six photolabile filter combinations to a standard irradiation. Then the in vitro UVA protection afforded by each combination was measured and compared with the persistent pigment darkening (PPD) values determined in vivo.

Results: The results clearly showed that pre‐irradiation does not affect the in vitro PPD factor of the photostable and photolabile samples in the same way. Almost identical values were determined for the stable filter combinations with and without pre‐irradiation, whereas distinct reductions in the in vitro factors by as much as 93% were observed after irradiation in the group of less stable filter combinations. Comparison of the in vivo and in vitro PPD factors showed that all 12 samples comprise a homogeneous distribution with identical factors before irradiation. After pre‐irradiation only the factors for the six less stable products were selectively reduced. The correlation with the data determined on the skin was clearly poorer for these products after irradiation.

Conclusion: Overall, the results showed that pre‐irradiation should not to be used for the assessment of UVA protection using this method. Furthermore, it can be assumed that normalizing the in vitro absorbance curves to the labelled SPF of the sunscreen will adequately take into account the photochemical behaviour of UV filters on the skin during sun exposure.
Calcium and pH patterning at the apical meristem are specifically altered by photoperiodic flower induction in Chenopodium spp.
Authors: ALBRECHTOVÁ J. T. P. , HEILSCHER S. , LESKE L. , WALCZYSKO P. , WAGNER E.
Published: December 2004

The apical meristem of the short‐day plant Chenopodium rubrum responds to photoperiodic flower induction with specific changes of pH and Ca2+ patterning immediately after the inductive dark span. The red–far‐red reversibility of the pH and Ca2+ patterning in response to night break treatments was measured in order to distinguish between the effect of the prolonged dark span per se and the specific effect of photoperiodic flower induction. In addition, the pH and Ca2+ patterning in C. rubrum was compared with the long‐day plant Chenopodium murale. The pH was visualized using the fluorescent probe carboxy SNARF‐1. Calcium ion concentrations were studied using a combination of Ca2+‐probes Fluo‐3 and Fura Red. It was observed that the specific changes in pH and Ca2+ patterning at the apical meristem of C. rubrum were abolished by the red‐light break. This effect was fully reversed with a subsequent single far‐red treatment. These observations infer the influence of phytochrome on both pH and Ca2+ patterning. Changes in pH and Ca2+ patterning upon flower induction were observed in both long‐day and short‐day plants. These results support the hypothesis that changes of pH and [Ca2+] in cells of the apical meristem are part of the pathway in signal transduction triggering flower initiation.
Lipids in roots of Pinus sylvestris seedlings and in mycelia of Pisolithus tinctorius during ectomycorrhiza formation: changes in fatty acid and sterol composition
Authors: LACZKO E. , BOLLER T. , WIEMKEN V.
Published: December 2004

The composition of fatty acids and sterols in soil lipid fractions is often used as a global indicator for the status and changes of soil microbial communities. In order to validate such analyses in the context of ectomycorrhizal communities, an experiment was performed in which seedlings of Pinus sylvestris and the fungus Pisolithus tinctorius were grown separately, or combined to form ectomycorrhiza under axenic conditions. Fatty acids of the neutral lipid fraction (NLFAs) and the phospholipid fraction (PLFAs) as well as sterols were identified and quantified by gas chromatography–mass spectrometry. When grown separately, the two organisms differed strongly with respect to the sterol composition. Sterols had a much higher relative abundance in the fungus in comparison with the plant, and the two main fungal sterols, ergosterol and 24‐ethyllanosta‐8,24(24′)‐diene‐3beta,22zeta‐diol (Et lano 8,24), as well as six minor fungal sterols were not found in the plant. On the other hand, the three sterols found in plant roots were absent from the fungus. With regard to fatty acids, the lipids of both organisms contained the same three major PLFAs, namely n16:0, 18:2–9,12c, and 18:1–9c. However, plant lipids contained, in addition, eight PLFAs and five NLFAs that were not present in the fungus. On the other hand, the fungus contained two PLFAs and two NLFAs that were not present in the plant. When the fungus and the plant were brought together, there was a drastic change in the lipid composition of the root: within a day, all the saturated fatty acids in the NLFA fraction increased very strongly and then slowly decreased but remained at an elevated level throughout the experiment. All these saturated fatty acids also started to appear in the extraradical fungal mycelium; they increased steadily and reached their highest levels at the end of the experiment. These results indicate that in symbiosis, the fungus transports plant lipids from the symbiotic interface to the extraradical mycelium. Concerning sterols, the extraradical mycelium acquired only a small amount of plant‐specific sterols. However, its ergosterol content steadily decreased whereas the content of Et lano 8,24 remained high, causing the ratio of these two sterols to decrease from 1 : 7 to 1 : 20, whereas in the ectomycorrhizal root, the opposite phenomenon occurred, so that the ratio increased to a value of almost 1 : 1. The marked changes in the composition of the extraradical mycelium were well reflected in a principal component analysis of all lipid components. The present results show that a given ectomycorrhizal fungus may display markedly different lipid compositions in its intraradical and extraradical parts. In addition, they highlight a potential role of plant lipid transfer from the root to the fungus in the functioning of the ectomycorrhizal symbiosis.
Starvation, osmotic stress and desiccation tolerance lead to expression of different genes of the regulatory β and γ subunits of the SnRK1 complex in germinating seeds of Medicago truncatula
Authors: Buitink J. , Thomas M. , Gissot L. , Leprince O.
Published: December 2004

The SnRK1 complex, a metabolic regulator of nutrient deficit in plants, consists of a catalytic α‐subunit and two regulatory subunits, β and γ that exist as several isoforms. To obtain insight into the developmental and stress conditions that regulate the expression of these regulatory subunits, four β subunits MtAKINβ1‐β4, and three γ subunits MtAKINβγ, MtSNF4b and MtAKINγ were identified and characterized in seeds of M. truncatula. Their transcripts were found to accumulate differentially in vegetative and seed tissues and appear to be differentially modulated during germination and the imposition of stress. MtAKINγ and MtAKINβ3 showed identical patterns of expression upon osmotic shock, whereas transcripts of MtAKINγ and MtAKINβ1 were strongly up‐regulated upon starvation of the radicles. Addition of glucose during the starvation process reversed this effect. MtAKINβ2 and MtSNF4b were specifically induced upon the re‐induction of desiccation tolerance in germinated, desiccation‐sensitive radicles, whereas only MtSNF4b expression was repressed by an inhibitor of abscisic acid synthesis. A second γ subunit, MtAKINβγ, was transiently expressed early during the induction of desiccation tolerance, and its expression could be modulated by blocking the respiratory ATP production by cyanide. The transcriptional regulation of the subunit isoforms showing identical expression profiles in germinating seeds appears to be under the control of different factors.
Effects of salinity, high irradiance, ozone, and ethylene on mode of photosynthesis, oxidative stress and oxidative damage in the C3/CAM intermediate plant Mesembryanthemum crystallinum L.
Authors: HURST A. C. , GRAMS T. E. E. , RATAJCZAK R.
Published: December 2004

The occurrence of oxidative stress and oxidative damage in the halophyte Mesembryanthemum crystallinum during C3/crassulacean acid metabolism (CAM) transition evoked by salinity and high irradiance was investigated. The hypothesis tested was that CAM induction will effectively protect M. crystallinum against oxidative damage even under additionally applied oxidative stress via ozone (150 p.p.b.) exposure. Salinity (0.4 m NaCl), high irradiance and ozone induced the cytosolic CuZn‐superoxide dismutase (SOD; EC 1.15.1.1) transcript abundance and activity indicating oxidative stress. However, ozone did not induce CAM. Contrary to the hypothesis, that ethylene may be involved in CAM induction, gassing with ethylene (200 p.p.b.) did not lead to CAM, but revealed that in M. crystallinum ethylene biosynthesis is induced by autostimulation. A putative fragment of the hitherto unknown nu‐cleotide sequence of 1‐aminocyclopropane‐1‐carboxylate oxidase (ACC; EC 4.4.1.14) was isolated and used as a specific probe against the ACC oxidase transcript to monitor oxidative damage. Ozone exposure increased the ACC oxidase expression only in plants with C3‐photosynthesis which also showed severe necrosis and reduced photosynthetic activity, whereas plants in CAM mode (salt induced) remained unaffected. Natural stressors such as salinity and high irradiance induce CAM and up‐regulate the ARS component CuZn‐SOD very effectively to protect M. crystallinum from oxidative damage even when additional oxidative stress such as ozone is present.
A role for the cuticular waxes in the environmental control of stomatal development
Authors: Holroyd Geoffrey H. , Hetherington Alistair M. , Gray Julie E.
Published: December 2004

The mechanism of guard cell development is currently attracting much interest. The recent use of Arabidopsis mutant plants has shed new light on the pathways that regulate the development and patterning of specialized cells such as guard cells, trichomes and roots hairs within the plant epidermis. Here, we review this literature focusing on the insights provided into guard cell development. We also discuss our current knowledge of how environmental variables may impact on guard cell development and, in particular, consider whether the composition of the epidermal waxes may be involved in this process.
Abnormal etioplast development in barley seedlings infected with BSMV by seed transmission
Authors: Harsányi Anett , Böddi Béla , Bóka Károly , Almási Asztéria , Gáborjányi Richard
Published: December 2004

The effect of barley stripe mosaic hordeivirus (BSMV) was studied on the ultrastructure of etioplasts, protochlorophyllide forms and the greening process of barley (Hordeum vulgare cv. Pannónia) plants infected by seed transmission. The leaves of 7‐ to 11‐day‐old etiolated seedlings were examined by transmission electron microscopy, fluorescence and absorption spectroscopy. The etioplasts of infected seedlings contained smaller prolamellar bodies with less regular membrane structure, while prothylakoid content was higher than in the control. The protochlorophyllide content of virus‐infected seedlings was reduced to 74% of the control. In the 77 K fluorescence spectra the relative amount of 655 nm emitting photoactive protochlorophyllide form decreased, and the amount of the 645 and 633 nm emitting forms increased in the infected leaves. A characteristic effect was observed in the process of the Shibata‐shift: 40 min delay was observed in the infected leaves. The results of this work proved that BSMV infection delays or inhibits plastid development and the formation of photosynthetic apparatus.
Arab American Adolescent  Perceptions and Experiences  with Smoking
Authors: Kulwicki Anahid , Hill Rice Virginia
Published: December 2004

Abstract  The purpose of this pilot study was to gather information on Arab American adolescent tobacco use behavior. This information was used to modify the Project Toward No Tobacco Use cessation program so that it would reflect the cultural values of Arab American youths. Focus group interviews were conducted to collect qualitative data from 28 Arab American adolescents between the ages of 14 and 18 years. The number of participants in the focus groups ranged from three to eight; four sessions were conducted. A moderator, fluent in Arabic and English, facilitated the group's interactions. Each group addressed five interview questions. Discussions were audiotaped and transcribed with the expressed permission of study participants. Qualitative analysis consisted of careful reading of the transcripts and of the field notes for the purpose of identifying recurring themes around tobacco use. Those that emerged were Being Cool; Being able to “Nshar ma'a al shabab” (hang out with the guys); Present Orientation; Smoking feels good, tastes good, and keeps your mind off trouble; Availability and Accessibility of tobacco; and Barriers to Smoking Cessation Programs. The results of the focus group discussions provided valuable information about the tobacco use perceptions and behaviors of Arab American adolescents and the youths' need for a culturally relevant smoking cessation program.
HIV Prevention Outreach in Black Communities of Three Rural North Florida Counties
Authors: Brown Emma J. , Brown Joseph S.
Published: December 2004

Abstract  Literature to guide HIV prevention outreach for southeastern rural blacks is limited despite the increasing prevalence of HIV infection in this population. Three men and one woman conducted HIV prevention outreach in three north Florida rural counties in teams of two. The workers received five days of training in additional homework assignments. The workers used HIV/AIDS outreach surveys to guide their 10‐ to 15‐minute outreach visits. Five hundred seventy‐four outreach contacts with blacks were made between January and June 2001 (329 in County 1, 176 in County 2, and 69 in County 3) with 347 women and 227 men. Eighty‐four percent of the persons contacted accepted literature, 47.5% accepted male condoms, and 31.9% accepted female condoms. More women (99.4%) were knowledgeable about HIV/AIDS than men (92.5%), and they reported taking precautions against infection more often than men (98% vs. 90.3%). Many blacks in rural north Florida were receptive to an HIV prevention outreach program that provided information, literature, and condoms on the street and in homes. These findings suggest that HIV prevention outreach should be expanded to reach more rural blacks, who are increasingly at risk for HIV infection.
Americans' Knowledge and Perceived Risk of Tuberculosis
Authors: Ailinger Rita L. , Lasus Howard , Dear Margaret
Published: December 2004

Abstract  Tuberculosis (TB) has resurged as a major public health problem in the United States, but there is minimal information on the public's knowledge of TB. The general population must become aware of the seriousness of the reemergence of TB. Using data from the National Health Interview Survey Supplement, this study examined knowledge and perceived risk of TB of 14,727 U.S. respondents. Results demonstrated some general knowledge of TB, several misconceptions, and low concern regarding their risk of contracting TB. Only 10.2% of the respondents perceived risk for themselves. Respondents reported perceived knowledge of TB at a high level, while their actual knowledge was lower. Gender, education, income, and ethnicity were associated with knowledge and perceived risk. Older people responded correctly to questions about TB knowledge more often than younger people. Conclusions were that public health nursing efforts need to be redirected toward health education regarding TB risk and spread, complementing existing screening and therapy programs.
Public Health Nursing Pioneer:  Jane Elizabeth Hitchcock  1863–1939
Authors: Hawkins Joellen W. , Watson John Charles
Published: December 2004

Abstract  Jane Elizabeth Hitchcock was one of many distinguished nursing leaders of the 19th and early 20th centuries who attended a women's college before enrolling in a nurse training school. Like many of her contemporaries with equally impeccable family credentials, Hitchcock was something of an enigma to her family for choosing nursing over teaching, the most common acceptable career for women of her social class. Hitchcock's endowment of character, according to contemporary Lavinia Dock, exemplified the best of her Puritan roots. Her contributions to the evolution of public health nursing and the integration of public health nursing content into curriculums of training schools rivaled the achievements in higher education of her famous father, grandfather, and brother but garnered no comparable recognition. Her life presents an interesting case for analysis of an independent woman, a characteristic shared by many pioneers in the early years of public health nursing: 1893 to 1920.
The Experience of Being a Client in an Alaska Public Health Nursing Home Visitation Program
Authors: DeMay Diane A.
Published: December 2004

Abstract  This qualitative study reports on the content analysis of 62 essays written by clients about their experiences in an Alaska public health nursing home visitation project for prevention of child abuse and neglect. Home visitation services were provided to two groups of demographically matched first‐time mothers: intense protocol services (intervention group) and ‘‘usual’’ services (current practice group). Intervention and current practice group essays were analyzed separately. The purpose was to determine how congruent client experiences were with public health nurse perspectives of the care they gave to clients. Similarities and differences between groups were also examined. Although in different order of frequency, themes about knowledge and learning, nurse qualities, validation of parenting skills, and suggestions emerged for both groups, but the intervention group essays were, on average, seven times longer and more descriptively rich. Client experiences were similar to public health nurse concepts of effective service and to other findings in existing research.
Cutaneous reactions to pine processionary caterpillar (Thaumetopoea pityocampa) in pediatric population
Authors: Vega M. L. , Vega J. , Vega J. M. , Moneo I. , Sánchez E. , Miranda A.
Published: December 2004

Cutaneous lesions caused by pine processionary caterpillar (Thaumetopoea pityocampa, TP) are frequent in pinewood areas. However, no epidemiological studies have been performed so far in the pediatric population. In this study, we evaluated the relevance of reactions to pine processionary caterpillar in the pediatric population of our environment and determined the possible role of an IgE‐mediated mechanism.

A questionnaire was developed and given to 1101 children and adolescents ranging from 3 to 17 years of age from rural areas with large pine forests. A total of 653 questionnaires were answered by the children or their parents. The search for immunoglobulin E (IgE)‐mediated cases was based on the presence of a suspected reaction to caterpillar and confirmed by in vivo (skin prick) and in vitro (immunoblotting) tests.

Sixty of the 653 people interviewed (9.18%) identified a cutaneous reaction from exposure to the processionary caterpillar. Within this group only four cases (6.7%) were because of an IgE‐mediated mechanism. The predominant clinical feature of these patients with allergy to caterpillar was contact urticaria.

We present the first study of cutaneous reactions to pine processionary caterpillar in a large pediatric population. This is a frequent pathology in pinery zones and only in a minority of the cases are because of an IgE‐mediated allergic mechanism. This fact contrasts with studies in adults, where this percentage is much greater.
Quantification of IgE antibodies simplifies the classification of allergic diseases in 4‐year‐old children. A report from the prospective birth cohort study – BAMSE
Authors: Wickman Magnus , Ahlstedt Staffan , Lilja Gunnar , Hamsten Marianne v Hage
Published: December 2004

Allergic diseases are common among small children, but it is still unclear how immunoglobulin E (IgE) antibodies to ambient allergens are distributed in a population‐based prospective material of children at 4 years of age. The study is based on 75% (n = 4089) of all eligible children from northern Stockholm, born between 1994 and 1996 in pre‐defined geographical areas. Data on exposure and outcome were obtained by parental questionnaires when the child was 3 months and 4 years of age. Of the 92% who responded to the 4 years of age questionnaire, serum was obtained in 88% of these children for analysis of IgE antibodies performed with Pharmacia CAP systemTM (Phadiatop® and food mix fx5®). An antibody level ≥0.35 kUA/l was considered as positive. A positive Phadiatop® or fx5® was found in 24% of the 4 years old children. A rather poor correlation was found between the two tests (r = 0.39). Occurrence of IgE antibodies ≥3.5 kU/l for both Phadiatop® and fx5® in combination could predict any suspected allergic disease [asthma, rhinitis, atopic eczema dermatitis syndrome (AEDS) and allergic reaction to food] to 97.4%. However, the presence of ≥3.5 kUA/l of Phadiatop® or fx5® used as single tests only, was far less efficient to predict any allergic disease. The two mixes of airborne and food allergens were also associated, not only to the severity of the allergic disease in terms of number of organ involved, but also to the severity of recurrent wheeze, in particular in boys with a positive Phadiatop® who exhibited significantly limited peak flows compared to those with a negative test.

Already at the age of 4, one child in four is sensitized to an allergen as assessed by Phadiatop® or food mix (fx5®). The presence of IgE antibodies seems not only to predict allergic diseases in this age group, but also relates to severity of such diseases, in particular to asthma. Notable, there was a poor correlation between Phadiatop® and fx5® that needs to be considered when identifying allergic diseases in young children. The study demonstrates that quantification of IgE antibodies in blood may be beneficial, not only to diagnose allergic diseases in young children, but especially to serve as a marker of severity of asthma.
Clinical and therapeutic aspects of allergic asthma in adolescents
Authors: Lombardi Carlo , Gani Federica , Landi Massimo , Boner Attilio , Canonica Giorgio Walter , Passalacqua Giovanni
Published: December 2004

Little is known about the management of asthma in adolescents. We aimed at evaluating these aspects, through a specific questionnaire, in the real life of adolescents with allergic asthma.The questionnaire was administered to a group of adolescents after a diagnosis of allergic asthma. The diagnosis was based on history, clinical examination, pulmonary function tests and allergy tests. One hundred and fifteen adolescents (65 males, mean age 16.5 years) fulfilled the criteria for allergic asthma. The questionnaire explored demography, family history, clinical history, previous diagnosis, therapy, attitude towards therapy and social aspects. The mean actual FEV1 was 87 ± 10%. Methacholine challenge was carried out in 79 patients and was always positive (PD20 < 1200 μg), whereas 36 patients underwent reversibility test. According to GINA guidelines, severity of asthma resulted intermittent in 62, mild persistent in 31, moderate in 19 and severe in three patients. In 61% of cases teachers were not aware of the disease. Asthma was managed by general practitioners, allergists and pulmonologists, but PFT/allergy tests had never been performed in 14% of patients. Forty‐two per cent of the adolescents received no therapy at all, and only 15% of those with persistent asthma were receiving a stable treatment. Seventy‐four per cent of adolescents preferred the inhaled, as against the oral, route. From a clinical and functional point of view, asthma in adolescents did not differ from other age ranges. Nevertheless, the management (diagnosis and therapy) emerged to be unsatisfactory from many points of view.
Increasing prevalence of allergic rhinitis but not asthma among children in Hong Kong from 1995 to 2001 (Phase 3 International Study of Asthma and Allergies in Childhood)
Authors: Lee So‐Lun , Wong Wilfred , Lau Yu‐Lung
Published: December 2004

There is a worldwide belief that the prevalence of asthma and other allergic diseases is increasing but the measures used in many studies are susceptible to systematic errors. We examined the trend of asthma, allergic rhinitis and eczema prevalence in school children aged 6–7 years in Hong Kong from 1995 to 2001 using standardized ISAAC methodology. There were 4448 and 3618 children participating in 2001 and 1995, respectively. The prevalence of life‐time rhinitis (42.4% vs. 38.9%, p < 0.01), current rhinitis (37.4% vs. 35.1%, p < 0.03), current rhinoconjunctivitis (17.2 vs. 13.6%, p < 0.01) and life‐time eczema (30.7% vs. 28.1%, p = 0.01) increased significantly. There was no significant change in prevalence of life‐time asthma, life‐time wheeze and current wheeze albeit a significant increase in severe asthma symptoms. We investigated a number of potential risk factors including sex, family history of atopy, sibship size, birth weight, respiratory tract infections, pet ownership and exposure to tobacco smoke. However, the increases in prevalence of rhinitis and eczema could not be entirely explained by the change of prevalence of these risk factors. The odds ratio OR for the study period remained significantly associated with current rhinitis (OR 1.31, 95% confidence intervals CI 1.17–1.46), current rhinoconjunctivitis (OR 1.63, 95% CI 1.41–1.87) and life‐time eczema (OR 1.30, 95% CI 1.16–1.45) after adjustment for these confounding variables using logistic regression model. Further study is warranted to elucidate the factors contributing to the observable change in the prevalence of rhinitis in our population.