bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of frequency of active Borna disease virus infection in Scottish blood donors
Authors: Davidson F. , Lycett C. , Petrik J. , Fazakerley J. K.
Published: March 2004

Background and Objectives  Borna disease virus (BDV) can infect a wide range of vertebrate species causing neurological disease. In order to ensure the safety of blood supplies, it is essential to monitor blood for emerging pathogens.

Materials and Methods  One‐hundred individual white cell pellets and pools representing 25 000 plasma donations from human blood were screened for BDV by reverse transcription–polymerase chain reaction (RT–PCR).

Results  BDV RNA was not detected in any of the samples.

Conclusions  The results indicate that BDV is not widely spread in the UK human population and does not represent a risk as a transfusion‐transmitted agent.
Quality control system for blood irradiation using a teletherapy unit
Authors: Góes E. G. , Covas D. T. , Haddad R. , Pelá C. A. , Formigoni C. E. , Borges J. C.
Published: March 2004

Background and Objectives  Irradiation of whole blood and blood components before transfusion is currently the only accepted methodology to prevent transfusion‐associated graft‐vs.‐host disease. In the present work, we developed an automated system for blood bag storage during irradiation, using a teletherapy unit.

Materials and Methods  A device with two thermal compartments was constructed in acrylic and foam, for the storage of blood bags during irradiation. An automatic acquisition system, coupled with an amplifier and a thermal‐sensitive probe, were developed to check blood temperature during irradiation. A polystyrene phantom was constructed to simulate the volume of blood routinely irradiated. The dose distribution was measured in the phantom using thermoluminescent dosimeters and represented in terms of isodose curves.

Results  The thermal device kept the blood temperature below 6 °C for more than 2 h. Our system allowed the simultaneous irradiation of two different blood components while maintaining a constant temperature. The temperature monitoring system remained invariant (0·2 °C) over the whole irradiation interval. Phantom dosimetric results showed a homogeneous dose distribution when the phantom was irradiated, using rotational fields with a 2 r.p.m. frequency.

Conclusions  The methodology developed in the present work provides appropriate storage conditions during irradiation of both red blood cells and platelet blood components using a teletherapy unit.
Influence of cell‐free DNA in plasma on real‐time polymerase chain reaction for determination of residual leucocytes in platelet concentrates
Authors: Dijkstra‐Tiekstra M. J. , Pietersz R. N. I. , Reesink H. W. , Van Der Schoot C. E.
Published: March 2004

Background and Objectives  Real‐time quantitative (RQ) polymerase chain reaction (PCR) can be used to determine the number of residual leucocytes in leucocyte‐reduced platelet concentrates (LR‐PCs), which should contain < 3·3 leucocytes/µl. In this study we investigated the extent to which cell‐free DNA, known to be present in plasma, might interfere with this determination. In this study, RQ‐PCR was employed to determine the following: the influence of filtration of platelet concentrates (PCs) on the amount of cell‐free DNA; the variation in concentration of cell‐free DNA between the buffy coats (BCs) of different donors; and the amount of cell‐free DNA during storage and processing of whole blood.

Materials and Methods  PCs were sampled before and after filtration (n = 5), BCs were sampled (n = 100) and whole blood units were sampled < 2 h and 16–20 h after collection, and the BCs were also sampled after processing the whole blood (n = 10). Samples were centrifuged to obtain cell‐free plasma in which the amount of cell‐free DNA was determined using an RQ‐PCR for the albumin gene.

Results  The amount of cell‐free DNA was not influenced by filtration of the PCs [1·7 ± 0·8 vs. 1·5 ± 0·8 leucocyte‐equivalents (eq)/µl]. However, the amount of cell‐free DNA in plasma of the BCs varied considerably, from 0·1 to 18·2 leucocyte‐eq/µl (median = 1·5 leucocyte‐eq/µl; mean ± SD: 2·2 ± 2·4 leucocyte‐eq/µl). In 18% of the BCs the amount cell‐free DNA was > 3·3 leucocyte‐eq/µl. The amount of cell‐free DNA increased during storage, from 0·3 ± 0·3 leucocyte‐eq/µl (< 2 h after collection) to 0·9 ± 0·6 leucocyte‐eq/µl (16–20 h after collection) and, after processing the whole blood, to 2·0 ± 2·0 leucocyte‐eq/µl.

Conclusions  Variable amounts of cell‐free DNA in plasma will interfere if RQ‐PCR is applied to estimate leucocyte numbers in leucocyte‐reduced PCs.
Clothing, charity, salvation and visionary experience in fifteenth‐century Siena
Authors: Warr Cordelia
Published: March 2004

This article investigates the use of clothing as a liminal object, capable of moving across the boundary between the mortal and immortal worlds. The significance of clothing within the changing consumer culture of Renaissance Italian society, and the legislation surrounding it, has been discussed by a number of recent authors. I consider a different, but connected, aspect of clothing: depictions and descriptions of supernatural apparitions relating to clothes. Despite notable changes in the perception and uses of clothing, 1215–1545 (from the Fourth Lateran Council to the opening of the Council of Trent) can be seen as a unified period of religious devotion dominated by belief in the resurrection of the body, purgatory and the cult of saints. These beliefs contribute to considerable evidence suggesting that for those living in Latin Europe dress existed on two planes – the material and the spiritual. Focusing on the fifteenth‐century decoration of the hospital of Santa Maria della Scala in Siena – by artists including Domenico di Bartolo, Vecchietta and Giovanni di Paolo – this article explores the tensions inherent in the changing relationship of clothing and adornment to the mortal and immortal body.

Cordelia Warr is Lecturer in the History of Art at the University of Manchester. She has worked on female patronage during the fourteenth century and is currently completing a monograph tentatively entitled Crossing Boundaries: Physical and Spiritual Clothing in Italian Art 1215–1545.
Impressions of difference: the painted canvases of Helen McNicoll
Authors: Huneault Kristina
Published: March 2004

This paper examines the works of Canadian impressionist painter Helen McNicoll (1879–1915), analysing them as creative inventions that mediate the irreducible gap between cultural symbolization and experience. McNicoll was a painter of women and girls, and the essay centres on the difference that gender makes in her canvases. Femininity is not the works' only operative axis of distinction, however. McNicoll's nationality and, most significantly, her deafness, conjoined with gender as constitutive and structurally overlapping elements of her pictorial production. The artist's applications of paint to canvas are visible renderings of an ambiguous relation to symbolization wrought by this conjunction. In this context, McNicoll's choice of pictorial style is especially apposite, and the paper explores the way in which impressionism's ideal of direct correspondence between experience and representation resonated forcibly with the ideologies of femininity and language available to a deaf woman painter at the beginning of the twentieth century.
Modulation of Na+,K+‐ATPase activity is of importance for RVD
Authors: Andersson R. M. , Aizman O. , Aperia A. , Brismar H.
Published: March 2004

Aim:  This study was performed to examine the role of Na+,K+‐ATPase activity for the adaptive response to cell swelling induced by hypoosmoticity, i.e. the regulatory volume decrease (RVD).

Methods:  The studies were performed on COS‐7 cells transfected with rat Na+,K+‐ATPase. To study changes in cell volume, cells were loaded with the fluorescent dye calcein and the intensity of the dye, following exposure to a hypoosmotic medium, was recorded with confocal microscopy.

Results:  Ouabain‐mediated inhibition of Na+,K+‐ATPase resulted in a dose dependent decrease in the rate of RVD. Total 86Rb+ uptake as well as ouabain dependent 86Rb+ uptake, used as an index of Na+,K+‐ATPase dependent K+ uptake, was significantly increased during the first 2 min following exposure to hypoosmoticity. Since protein kinase C (PKC) plays an important role in the modulation of RVD, a study was carried out on COS‐7 cells expressing rat Na+,K+‐ATPase, where Ser23 in the catalytic α1 subunit of rat Na+,K+‐ATPase had been mutated to Ala (S23A), abolishing a known PKC phosphorylation site. Cells expressing S23A rat Na+,K+‐ATPase exhibited a significantly lower rate of RVD and showed no increase in 86Rb+ uptake during RVD.

Conclusion:  Taken together, these results suggest that a PKC‐mediated transient increase in Na+,K+‐ATPase activity plays an important role in RVD.
Decreased availability of intestinal dopamine in transmural colitis may relate to inhibitory effects of interferon‐γ upon L‐DOPA uptake
Authors: Magro F. , Fraga S. , Ribeiro T. , Soares‐da‐Silva P.
Published: March 2004

Aims: 
The present study aimed to evaluate the relationship between intestinal inflammation, interferon‐γ (IFN‐γ) levels and intestinal levels of dopamine, its precursor l‐3,4‐dihydroxyphenylalanine (l‐DOPA), and the activity of aromatic l‐amino acid decarboxylase (AADC) activity along the digestive tract in a rat experimental model of colitis.

Methods:  Colitis was induced by rectal administration of 2,4,6‐trinitrobenzene sulphonic acid (TNBS). Catechol derivatives were assayed by means of HPLC‐EC.

Results:  It is shown that dopamine and noradrenaline levels in the distal colon (inflamed mucosa), but not in the ileum (non‐inflamed mucosa), of TNBS‐treated rats were markedly lower than in control animals. A slight decrease in l‐DOPA tissue levels, no changes in AADC activity and an increase in plasma IFN‐γ levels accompanied this decrease in dopamine levels. Exposure of Caco‐2 cells, a human intestinal epithelial cell line, to human IFN‐γ resulted in a concentration‐dependent and long‐lasting inhibition of l‐DOPA uptake, which most likely explains the decrease in dopamine levels in the inflamed mucosa.

Conclusion:  Changes in tissue levels of noradrenaline and dopamine in experimental colitis in the rat follow a similar pattern to that observed in patients with Crohn's disease and ulcerative colitis. In this model of experimental colitis, the decrease in dopamine levels is most likely explained by the inhibitory effect of IFN‐γ on l‐DOPA uptake by intestinal epithelial cells.
Mental stress inhibits pain perception and heart rate variability but not a nociceptive withdrawal reflex
Authors: Terkelsen A. J. , Andersen O. K. , Mølgaard H. , Hansen J. , Jensen T. S.
Published: March 2004

Aim:  Do distraction from‐ or attention to sural nerve stimulation affect pain, heart rate variability, and a spinal withdrawal reflex?

Material and methods:  In 26 male volunteers, electrical stimulation at the distal cutaneous receptive field of the sural nerve elicited pain and a nociceptive withdrawal reflex. Intensity of pain was rated on a numeric rating scale. Electromyographic reflex responses were measured from biceps femoris muscle. Cardiac autonomic function was estimated by heart rate variability measures and was expressed in the time domain as mean of RR‐intervals for normal heart beats (mean‐RR) and standard deviation of all normal RR‐intervals (SD‐NN) and, in the frequency domain, where pure vagal activity was assessed by high frequency power (0.15–0.4 Hz). Low frequency power (0.04–0.15 Hz) reflects both parasympathetic and sympathetic control. Effect parameters were recorded before and during random distraction and attention. Distraction from sural nerve stimulation was induced by a mental arithmetic test, paced auditory serial addition task (PASAT), while attention was induced by concentrating on painful foot stimulation.

Results:  Paced auditory serial addition task decreased mean‐RR and SD‐NN, frequency domain parameters, as well as pain (P < 0.001). In contrast, PASAT did not change the spinal withdrawal reflex. Attention did not affect any effect parameter.

Conclusion:  Distraction by PASAT altered autonomic activity and inhibited pain but failed to affect withdrawal reflex responses, while attention had no effect on either parameter. Psychological distraction and attention may have different effects on noxious evoked pain perception and autonomic activity. Pain relief during PASAT probably involves supraspinal mechanisms.
Effect of angiotensin II and endothelin‐1 receptor blockade on the haemodynamic and hormonal changes after acute blood loss and after retransfusion in conscious dogs
Authors: Francis R. C. E. , Höhne C. , Kaczmarczyk G. , Boemke W.
Published: March 2004

Aim:  This study investigates angiotensin II and endothelin‐1 mediated mechanisms involved in the haemodynamic, hormonal, and renal response towards acute hypotensive haemorrhage.

Methods:  Conscious dogs were pre‐treated with angiotensin II type 1 (AT1) and/or endothelin‐A (ETA) receptor blockers or not. Protocol 1: After a 60‐min baseline period, 25% of the dog's blood was rapidly withdrawn. The blood was retransfused 60 min later and data recorded for another hour. Protocol 2: Likewise, but preceded by AT1 blockade with i.v. Losartan. Protocol 3: Likewise, but preceded by ETA blockade with i.v. ABT‐627. Protocol 4: Likewise, but with combined AT1plus ETAblockade.

Results:  In controls, haemorrhage decreased mean arterial pressure (MAP) by approximately 25%, cardiac output by approximately 40%, and urine volume by approximately 60%, increased angiotensin II (3.1‐fold), endothelin‐1 (1.13‐fold), vasopressin (116‐fold), and adrenaline concentrations (3.2‐fold). Glomerular filtration rate and noradrenaline concentrations remained unchanged. During AT1 blockade, the MAP decrease was exaggerated (−40%) and glomerular filtration rate fell. During ETA blockade, noradrenaline increased after haemorrhage instead of adrenaline, and the MAP recovery after retransfusion was blunted. The decrease in cardiac output was similar in all protocols.

Conclusions:  Angiotensin II is more important than endothelin‐1 for the short‐term regulation of MAP and glomerular filtration rate after haemorrhage, whereas endothelin‐1 seems necessary for complete MAP recovery after retransfusion. After haemorrhage, endothelin‐1 seems to facilitate adrenaline release and to blunt noradrenaline release. Haemorrhage‐induced compensatory mechanisms maintain blood flow more effectively than blood pressure, as the decrease in cardiac output – but not MAP – was similar in all protocols.
Inhibition of BK channels contributes to the second phase of the response to TRH in clonal rat anterior pituitary cells
Authors: Haug T. M. , Hafting T. , Sand O.
Published: March 2004

Aim:  Thyrotropin‐releasing hormone (TRH) induces biphasic changes in the electrical activity, the cytosolic free Ca2+ concentration ([Ca2+]i), and prolactin secretion from both GH cells and native lactotrophs. It is well established that inhibition of erg channels contributes to the second phase of the TRH response. We have investigated if BK channels are also involved.

Results:  The BK channels may be active at the resting membrane potential (open probability, Po = 0.01) in clonal rat anterior pituitary cells (GH4), which makes it possible that inhibition of these channels may contribute to the reduced K+ conductance during the TRH response. The specific BK channel blocker iberiotoxin (IbTx, 100 nm) had no effect on the resting conductance at holding potentials negative to −40 mV, but significantly reduced the conductance at shallower membrane potentials. This corresponds to the voltage dependency of the sustained [Ca2+]i. Furthermore, IbTx increased the action potential frequency by 36% in spontaneously firing cells. During the second phase of the TRH response, the action potential frequency increased by 34%, concomitantly with 61% reduction of the Po of single BK channels. The protein kinase C (PKC)‐activating phorbol ester TPA had no significant effect on BK channel Po within the normal range of the resting potential.

Conclusion:  The BK channels may contribute to the resting membrane conductance, and they are partially inhibited by TRH during the second phase. This modulation seems not to depend on PKC. We propose that inhibition of erg and BK channels acts in concert to enhance the cell excitability during the second phase of the response to TRH.
Botulinum neurotoxin to treat chronic anal fissure: results of a randomized ‘Botox vs. Dysport’ controlled trial
Authors: Brisinda G. , Albanese A. , Cadeddu F. , Bentivoglio A. R. , Mabisombi A. , Marniga G. , Maria G.
Published: March 2004

Background : Botulinum neurotoxin induces healing in patients with idiopathic fissure. The optimal dosage is not well established.

Aim : To compare the efficacy and tolerability of two different formulations of type A botulinum neurotoxin, and to provide more evidence with regard to the choice of dosage regimens.

Methods : Symptomatic adults with chronic anal fissure were enrolled in a randomized study. The outcome of each group was evaluated clinically, and by comparing the pressure of the anal sphincters before and after treatment.

Results : Fifty patients received injections of 50 units of Botox formulation (group I), and 50 patients received injections of 150 units of Dysport toxin (group II). One month after injection, 11 patients in group I and eight in group II had mild incontinence of flatus. At the 2‐month evaluation point, 46 patients in group I and 47 patients in group II had a healing scar. In group I patients, the mean resting anal pressure was 41.8% lower, and the maximum voluntary squeeze pressure was 20.2% lower, than the baseline value. In group II patients, the resting anal pressure and maximum voluntary squeeze pressure were 60.0 ± 12.0 mmHg and 71.0 ± 30.0 mmHg, respectively. There were no relapses during an average of about 21 months of follow‐up.

Conclusions : Botulinum neurotoxin may be considered an effective treatment in patients with chronic anal fissure. The efficacy and tolerability of the two different formulations of botulinum neurotoxin were indistinguishable.
Genetic characterization of four strains of Nile tilapia (Oreochromis niloticus L.) using microsatellite markers
Authors: Rutten M. J. M. , Komen H. , Deerenberg R. M. , Siwek M. , Bovenhuis H.
Published: March 2004

Four domesticated strains of Nile tilapia (Oreochromis niloticus L.) were genetically characterized using 14 microsatellite markers and 64 animals per strain. Two strains, Chitralada (AIT) and International Development Research Centers (IDRC) were obtained from the AIT institute, Bangkok, Thailand. The GIFT strain (5th generation) came from NAGRI, Thailand, and the GÖTT strain was supplied by the University of Göttingen, Germany. The average numbers of alleles per marker were 5.0 (GÖTT), 5.4 (AIT), 5.6 (IDRC) and 7.5 (GIFT). Private alleles were found at all markers with the exception of two. No fixation of alleles was found at any marker. Population differentiation, FST, was 0.178 (great genetic differentiation) and confirmed grouping of the animals in strains. The expected level of heterozygosity ranged from 0.624 to 0.711, but the observed level of heterozygosity significantly deviated from the expected level in three strains. This was probably because of small population size. Moderate to great genetic differentiation was found between strains. A phylogenetic tree reflected the strains known histories. Application of the Weitzman approach showed that all strains have added value for the total genetic diversity and thus should be retained.
A microsatellite linkage map for Atlantic salmon (Salmo salar)
Authors: Gilbey J. , Verspoor E. , McLay A. , Houlihan D.
Published: March 2004

A linkage map of the Atlantic salmon is described here consisting of 15 linkage groups containing 50 microsatellite loci with a 14 additional unlinked markers (including three allozymes). The map shows the largest sex‐specific recombination rate differences so far found in any vertebrate species (3.92:1 female:male). Homologies with previous linkage mapping studies of Atlantic salmon and rainbow trout are described. An in silico search of the Genbank database carried out using the microsatellites used in the mapping process identified significant matches between the flanking regions of the microsatellite SS11 and the calcium‐binding mitochondrial carrier protein, ‘Aralar1’.
A linkage map of Atlantic salmon (Salmo salar) reveals an uncommonly large difference in recombination rate between the sexes
Authors: Moen T. , Hoyheim B. , Munck H. , Gomez‐Raya L.
Published: March 2004

A genetic linkage map of the Atlantic salmon (Salmo salar) was constructed, using 54 microsatellites and 473 amplified fragment length polymorphism (AFLP) markers. The mapping population consisted of two full‐sib families within one paternal half‐sib family from the Norwegian breeding population. A mapping strategy was developed that facilitated the construction of separate male and female maps, while retaining all the information contributed by the dominant AFLP markers. By using this strategy, we were able to map a significant number of the AFLP markers for which all informative offspring had two heterozygous parents; these markers then served as bridges between the male and female maps. The female map spanned 901 cM and had 33 linkage groups, while the male spanned 103 cM and had 31 linkage groups. Twenty‐five linkage groups were common between the two maps. The construction of the genetic map revealed a large difference in recombination rate between females and males. The ratio of female recombination rate vs. male recombination rate was 8.26, the highest ratio reported for any vertebrate. This map constitutes the first linkage map of Atlantic salmon, one of the most important aquaculture species worldwide.
Comparison of GNRH3 genes across salmonid genera
Authors: Leder E. H. , Danzmann R. G. , Ferguson M. M.
Published: March 2004

Genomic sequences of gonadotropin‐releasing hormone genes were amplified and examined for sequence divergence among members of three different genera of the subfamily Salmoninae: rainbow trout (Oncorhynchus mykiss), Atlantic salmon (Salmo salar), and Arctic charr (Salvelinus alpinus). Sequences of GNRH3A and GNRH3B (formerly known as sGnRH1 and sGnRH2) were 97–99% similar in coding regions and 94–98% similar in non‐coding regions among genera, but comparisons within species between GNRH3A and GNRH3B were only 90–92% similar in coding regions and 83–89% similar in non‐coding regions. Polymorphisms in the parents of mapping families for each species allowed for linkage mapping of the GNRH3B gene in all three species and the GNRH3A gene in rainbow trout. GNRH3B maps to linkage group 6 in rainbow trout, linkage group 16 in Atlantic salmon and linkage group 25 in Arctic charr. GNRH3A mapped to linkage group 30 in rainbow trout.
A missense mutation in the bovine leptin receptor gene is associated with leptin concentrations during late pregnancy
Authors: Liefers S. C. , Veerkamp R. F. , te Pas M. F. W. , Delavaud C. , Chilliard Y. , van der Lende T.
Published: March 2004

The leptin receptor (LEPR) gene consists of 20 exons divided over 1.75 Mb. Parts of bovine LEPR exon 4 (79 bp), exon 11 (95 bp) and exon 20 (513 bp) of 20 cows (Holstein‐Friesian) were sequenced (AJ580799; AJ580800; AJ580801) in an attempt to find polymorphisms. In exons 4 and 11 no SNPs were found. In exon 20, a T to C missense mutation was found at nucleotide 115, which causes an amino acid substitution at residue 945 (T945M). Frequencies for alleles C and T were 0.93 and 0.07 respectively, in a population of 323 Holstein‐Friesian cows and TT animals were not detected. Using genotypes of these cows an association study was performed for leptin concentrations during late pregnancy and lactation. Leptin concentrations were determined by radioimmunoassay (RIA). The T945M mutation showed an association with circulating leptin concentrations only during late pregnancy (P < 0.05) but not during lactation (P > 0.05). The CC genotype had higher concentrations than the CT genotype during this period. A combined effect with previously described leptin polymorphisms on prepartum leptin concentrations was observed, with one genotype combination having significantly lower levels of leptin up to 50 days, but interaction effects were not significant. The T945M polymorphism may have induced a structural change in the intracellular domain of the LEPR, which may have influenced the signal transduction pathway. However, the effect was found only for the heterozygous genotype because the TT genotype was not detected in this population of 323 Holstein‐Friesian cows.
Filière agrométéorologie pour l’élaboration des Avertissements Agricoles en France*
Authors: Jacquin D. , Rouzet J. , Delos M.
Published: March 2004

Les Avertissements Agricoles en France ont pour objectif de fournir des informations règlementaires, d’aider à la surveillance phytosanitaire du territoire et surtout de donner les moyens de réduire le nombre de traitements. Nos modèles aident essentiellement à cerner les facteurs climatiques, soit en situant globalement le risque de l’année en cours, soit en précisant l’effet de la diversité des climats régionaux. Dans une moindre mesure, les pratiques culturales sont intégrées. Le but reste de formuler des conseils concernant les plages de risques, la nécessité d’un traitement ou non, le choix des produits, les observations à effectuer. La mise en œuvre des modèles n’est possible qu’en s’appuyant sur un réseau de stations automatiques de climatologie maintenu avec soin. En parallèle un réseau d’observations biologiques est toujours nécessaire. L’utilisation de 28 modèles par les Services Régionaux de la Protection des Végétaux est passée en revue. Au niveau de l’épidémiologie, la question de l’intégration dans un même modèle des paramètres climatiques et agronomiques se pose toujours, ainsi que celle du niveau de complexitéà ne pas dépasser pour garder une bonne robustesse.
Evaluation of an action threshold‐based IPM wheat model in Rheinland (Germany) in 1999/2001*
Authors: Heger M. , Oerke E.‐C. , Dehne H.‐W. , Hindorf H.
Published: March 2004

Under the specific agricultural and climatic conditions of Rheinland (DE), 48 field trials in three years demonstrated the practicability of the action threshold‐based fungicide strategy of the IPM wheat model. The underlying data for action thresholds and dosage of fungicides applied are outlined. The cereal pathogens concerned, predominantly Mycosphaerella graminicola and Puccinia recondita, were controlled in the early stages of epidemic development using reduced rates of fungicides. The IPM wheat model gave a high efficacy of control, in terms of disease incidence and disease severity, under both low and high disease pressure conditions. The yield levels resulting from this effective reduction in diseases were nearly the same as those of the disease‐free variant. Total yield increase varied between 15% and 30% with an overall average of around 20%, and resulted in monetary benefits of 50–100 EUR ha−1 in the years considered.
A model simulating deposition of Venturia inaequalis ascospores on apple trees*
Authors: Rossi V. , Giosuè S. , Bugiani R.
Published: March 2004

Based on existing physical theories and models, a dynamic model estimating the concentration of Venturia inaequalis ascospores in the orchard air and their deposition on apple leaves was elaborated. The model produces two main outputs: number of ascospores deposited per leaf and proportion of ascospores discharged from pseudothecia deposited onto the leaves. The model has a relatively simple structure, and computations are based on few algorithms, which are implemented on an electronic data sheet of common use. Nevertheless, it preserves the accuracy of more complex physical models reasonably well. The model includes the effect of meteorological conditions and horticultural characteristics, and thus provides information for each type of orchard. Few input variables are required: wind speed and rainfall rate can be measured in standard meteorological stations; horticultural characteristics of the orchard can be determined for each type of orchard. The model produces conservative estimates of ascospore deposition, because it assumes a complete retention of the spores deposited by rainfall and does not consider either deposition on stems and flowers or the spatial distribution of plant surfaces. After further validation under orchard conditions, the model will be used to obtain better estimates of scab infection risk in current scab control strategies.
Development of overwintering oospores of Plasmopara viticola and severity of primary foci in relation to climate*
Authors: Rouzet J. , Jacquin D.
Published: March 2004

The French Plant Protection Service uses different techniques to provide advice on treatments against grapevine downy mildew: observation of primary foci, development of overwintering oospores and climate‐based forecasting models. This system is generally satisfactory but is time‐consuming, and the models used sometimes give a false evaluation of the severity of primary foci. We have accumulated 30 years of observations on the latter, together with the maturation of overwintering oospores. The severity of primary foci is linked to spring and autumn rainfall. Oospore maturation is affected by low autumn and warm spring temperatures. Long dry periods can block maturation. While there is little prospect that oospore maturation can be modelled in the near future, success can be expected for primary foci.
A web‐based decision support system for integrated management of cereal pests
Authors: Hagelskjær L. , Jørgensen L. Nistrup
Published: March 2004

The models in the Danish decision support system (DSS) PC‐Plant Protection (PC‐P) have been developed during the past 15 years of research on cereal pests in Denmark. Recently, the system was reintroduced as a web‐based DSS and is now called Crop Protection Online (CPO). CPO includes models for powdery mildew, rusts, septoria, rhynchosporium, net blotch, eyespot, aphids and leaf beetle larvae and is based on empirical data on: (i) the specific effect of each plant protection product; (ii) control thresholds; (iii) importance of pests according to growth stage; (iv) variation in susceptibility to pathogens among cultivars; and (v) influence of weather on the development of pests. The system has been validated in numerous trials and has proved to give good control of pathogens at low product inputs. The margin of product use has been similar or better compared with standard treatments included in the field trials. In trials where CPO was compared with other DSS, CPO resulted in the lowest input of fungicides, measured as TFI (TFI expresses the ratio applied doses/standard doses throughout a growing season) and the highest margin over product use. Differences in the prices of fungicides and in the grain price may change that. The system is under development in Poland and the Baltic countries, and is also ready for export to other countries.
Computer aids for plant protection in Latvia*
Authors: Turka I. , Priekule I.
Published: March 2004

The main agricultural crops where decision support systems (DSS) can be used via the Internet in Latvia are winter and spring cereals and potato. Two PC‐based models, forming part of a Danish DSS, were tested under the agroecological conditions of Latvia in 1999/2002: PC‐Plant Protection to control diseases in cereals and several modifications of the NegFry model for prediction of potato late blight. The results of 4 years of trials suggest that models that satisfy the needs of one pest may not fit another. The main reasons for failure to adapt PC models are differences in cultivar susceptibility, differences in pathogenicity, simultaneous action of other organisms and spatial placement of crops (forests, rivers and fallow land). For example, it is well known that, with the recent global migration of more aggressive strains and populations of Phytophthora infestans, late blight epidemics have become less predictable and, at the same time, less controllable in potato‐growing areas. For cereals, there is a different spectrum of prevailing pathogens, causing different levels of damage, requiring incorporation into models of thresholds corresponding to local conditions. Data from weekly monitoring of local fields, warnings about the local situation and meteorological information via the Internet are the most important computer‐aided elements for experts in plant protection.
GEWIS, a weather‐based decision support system for timing the application of plant protection products*
Authors: Bouma E.
Published: March 2004

Weather circumstances before, during and after the application of plant protection products are very important for efficacy. Knowledge of the behaviour of products in relation to weather circumstances can be an aid to achieving better efficacy and even serve as a tool for reducing the dose in well‐defined applications. Formulation type and dynamic build‐up of the wax layer on the upper side of the leaf are important for sticking and the speed and method of uptake of active substances into the leaves. It is difficult for farmers to combine all the important processes. Knowledge of the relations between plant protection products and meteorological conditions is combined in a decision support system (DSS) with the acronym GEWIS. The system calculates (hourly based) the physical behaviour of products at different stages in the process. With the help of this DSS, the farmer can choose the best moment of the day to apply a product with the optimum dose. Furthermore, users learn when it is possible to apply lower dosages and when not to apply at all.
Fatty acid metabolism assessed by 125I‐iodophenyl 9‐methylpentadecanoic acid (9MPA) and expression of fatty acid utilization enzymes in volume‐overloaded hearts
Authors: Miyamoto T. , Takeishi Y. , Tazawa S. , Inoue M. , Aoyama T. , Takahashi H. , Arimoto T. , Shishido T. , Tomoike H. , Kubota I.
Published: March 2004

Background  The peroxisome proliferator‐activated receptor (PPAR) α is a member of the nuclear receptor superfamily and regulates gene expression of fatty acid utilization enzymes. In cardiac hypertrophy and heart failure by pressure‐overload, myocardial energy utilization reverts to the fetal pattern, and metabolic substrate switches from fatty acid to glucose. However, myocardial metabolism in volume‐overloaded hearts has not been rigorously studied. The aim of the present study was to examine fatty acid metabolism and protein expressions of PPARα and fatty acid oxidation enzymes in volume‐overloaded rabbit hearts.

Methods  Volume‐overload was induced by carotid‐jugular shunt formation. Sham‐operated rabbits were used as control. Chronic volume‐overload increased left ventricular weight and ventricular cavity size, and relative wall thickness was decreased, indicating eccentric cardiac hypertrophy. 125I‐iodophenyl 9‐methylpentadecanoic acid (9MPA) was intravenously administered, and animals were sacrificed at 5 min after injection. The 9MPA was rapidly metabolized to iodophenyl‐3‐methylnonanoic acid (3MNA) by β‐oxidation. Lipid extraction from the myocardium was performed by the Folch method, and radioactivity distribution of metabolites was assayed by thin‐layer chromatography. The protein was extracted from the left ventricular myocardium, and levels of PPARα and fatty acid oxidation enzymes were examined by Western blotting.

Results  Myocardial distribution of 9MPA tended to be more heterogeneous in shunt than in sham rabbits (P = 0·06). In volume‐overloaded hearts by shunt, the conversion from 9MPA to 3MNA by β‐oxidation was faster than the sham‐control hearts (P < 0·05). However, protein levels of PPARα and fatty acid utilization enzymes were unchanged in shunt rabbits compared with sham rabbits.

Conclusions  These data suggest that myocardial fatty acid metabolism is enhanced in eccentric cardiac hypertrophy by volume‐overload without changes in protein expressions of PPARα and fatty acid utilization enzymes. Our data may provide a novel insight into the subcellular mechanisms for the pathological process of cardiac remodelling in response to mechanical stimuli.
Glutathione depletion and cardiomyocyte apoptosis in viral myocarditis
Authors: Kytö V. , Lapatto R. , Lakkisto P. , Saraste A. , Voipio‐Pulkki L.‐M. , Vuorinen T. , Pulkki K.
Published: March 2004

Background  The course of viral myocarditis is highly variable. Oxidative stress and Bcl‐2 family genes may play a role in its pathogenesis by regulating the amount of cardiomyocyte apoptosis. Apoptosis is difficult to detect and quantify in vivo. Therefore, we set to look for indicators of this potentially preventable form of cell death during various phases of experimental murine coxsackievirus B3 myocarditis.

Methods  BALB/c mice were infected with the cardiotropic coxsackievirus B3 variant. Glutathione (HPLC), cardiomyocyte apoptosis (TUNEL and caspase‐3 cleavage), Bax and Bcl‐XL mRNA expression (real time RT‐PCR), histopathology and viral replication (plaque assay and real time RT‐PCR) were measured from day 3 to day 20 after infection.

Results  Infection caused severe myocarditis and led to progressive decrease of plasma glutathione levels. Myocardial mRNA levels of pro‐apoptotic Bax and antiapoptotic Bcl‐XL were significantly increased from day 3 onwards. Bax mRNA and ratio of Bax to Bcl‐XL correlated with cardiomyocyte apoptosis (r = 0·77, P = < 0·001 and r 0·51, P < 0·01, respectively). Cardiomyocyte apoptosis was highest on day 5, coinciding with a rapid decline in plasma glutathione (r = −0·52, P = 0·003).

Conclusions  Systemic oxidative stress as indicated by decreased plasma glutathione levels coincides with cardiomyocyte apoptosis in experimental coxsackievirus myocarditis. Decreased plasma glutathione levels and changes in cardiac Bax and Bcl‐XL mRNA expression identify a phase of myocarditis in which the potentially preventable cardiomyocyte apoptosis is mostly observed.
Correlates of total homocysteine plasma concentration in type 2 diabetes
Authors: Russo G. T. , Di Benedetto A. , Giorda C. , Alessi E. , Crisafulli G. , Ientile R. , Di Cesare E. , Jacques P. F. , Raimondo G. , Cucinotta D.
Published: March 2004

Background  Although well‐defined in the general population, correlates of total homocysteine (tHcy) plasma concentration have not been sufficiently evaluated in diabetes. We investigated factors potentially associated with tHcy concentration in a cohort of type 2 diabetic subjects.

Materials and methods  The common methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism, fasting tHcy, vitamin B12 and folate plasma levels were assessed in 312 diabetic subjects, whose clinical, metabolic and lifestyle information was also available.

Results  The MTHFR genotype distribution was comparable to the Hardy–Weinberg equilibrium, with an overall TT homozygous frequency of 22%. Fasting tHcy concentration was significantly higher in men than in women (P < 0·001). Multivariate‐adjusted tHcy concentration was significantly different across the quartiles of age (P < 0·001), folate (P = 0·01), vitamin B12 (P = 0·03), creatinine concentrations (P = 0·001) and smoking (P = 0·02). Overall, significant trends were noted for creatinine clearance (P for trend = 0·02) and systolic blood pressure (BP) (unadjusted P for trend = 0·01), whereas no differences were noted according to BMI, diastolic BP, presence of hypertension, and diabetes‐related variables, such as diabetes duration, fasting glucose and glycated haemoglobin concentrations, current treatment and diabetes long‐term complications. Total homocysteine levels significantly correlated with age, systolic BP, vitamin B12, creatinine and creatinine clearance, but only age, creatinine, folate and vitamin B12 levels were independently associated with tHcy concentration in stepwise regression analysis.

Conclusions  Age, creatinine, folate, vitamin B12, and to a minor extent, sex, smoking, TT genotype and systolic BP were significantly associated with Hcy plasma concentration in type 2 diabetes, whereas no significant associations were noted with diabetes‐related variables.
Improved metabolic control decreases platelet activation markers in patients with type‐2 diabetes
Authors: Eibl N. , Krugluger W. , Streit G. , Schrattbauer K. , Hopmeier P. , Schernthaner G.
Published: March 2004

Background  Cardiovascular disease is associated with platelet dysfunction in patients with diabetes. Hyperglycaemia is known as an independent risk factor for micro‐ and macrovascular complications, and improvement of metabolic control has shown beneficial effects on diabetic late complications. Our study attempts to clarify the effect of improved metabolic control on platelet activation markers in patients with type‐2 diabetes.

Materials and methods  Thirty patients were studied at baseline and 3 months after improvement of metabolic control and compared with an age‐matched nondiabetic control group. Platelet activation markers (CD31, CD36, CD49b, CD62P and CD63) were assessed by flow cytometry analysis.

Results  Significantly more activated platelets were detected in patients with diabetes compared with controls. After 3 months’ improvement of metabolic control, a significant decline of all platelet activation markers except CD36 was noted. Furthermore a significant correlation between CD62P, CD63 and HbA1c levels was observed.

Conclusions  We conclude therefore that improvement of metabolic control has a beneficial effect on platelet activation. This may have an implication in the pathogenesis of vascular disease in patients with type‐2 diabetes.
Changes in vulnerability of Daphnia to an insecticide application depending on the population phase
Authors: Hanazato Takayuki , Hirokawa Haruka
Published: March 2004

1. Laboratory populations of cloned Daphnia pulex at three population phases (growing phase, density peak, declining phase) were exposed to the insecticide carbaryl at 15 μg L−1, which killed juveniles but not adults.

2. The population decline was largest and recovery was slowest when the chemical was applied at the density peak, indicating that the population was most sensitive to the chemical at that stage. Populations in the declining phase were least affected by the treatment.

3. We propose that food condition, which varies with population density, was a major factor affecting vulnerability to carbaryl. In that case, Daphnia populations in lakes would be most vulnerable to toxic chemicals during food‐limited condition such as the spring clear‐water phase.
Phosphate limitation influences the sensitivity to copper in periphytic algae
Authors: Guasch Helena , Navarro Enrique , Serra Alexandra , Sabater Sergi
Published: March 2004

1. To assess the influence of nutrient limitation on copper toxicity, periphitic communities from an oligotrophic stream were exposed to copper for six to 12 days with and without the supply of nutrients (mainly P).

2. In contrast to the hypothesis that nutrient cycling in mature biofilms would protect them from Cu toxicity, low and high biomass biofilms did not differ in their physiological response to copper after 6 days of exposure.

3. A clear influence of P‐limitation on copper toxicity was observed. Periphytic communities that were previously fertilised for 18 days were three times more tolerant than control communities indicating that P‐limitation enhanced Cu toxicity and tolerance induction were probably related to the higher P‐availability. In addition, a compensation of Cu toxicity after P‐addition was observed in the long‐term (after 12 days).

4. We conclude that periphyton from oligotrophic streams is more sensitive to copper than periphyton from fertilised streams, and that therefore a higher effect of chronic copper exposure is expected to occur in oligotrophic P‐limited fluvial systems.

5. Extrapolation of our results to the area of study (Catalonia, north‐east of Spain) indicates that while the levels of Cu commonly found in the zone may negatively affect the periphyton from oligotrophic streams, because of the interaction between Cu and P, they are not able to control the growth of nuisance algae which is common under high nutrient conditions.
The effects of macroinvertebrate taxonomic resolution in large landscape bioassessments: an example from the Mid‐Atlantic Highlands, U.S.A.
Authors: Waite Ian R. , Herlihy Alan T. , Larsen David P. , Urquhart N. Scott , Klemm Donald J.
Published: March 2004

1. During late spring 1993–1995, the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) sampled 490 wadeable streams in the mid‐Atlantic Highlands (MAH) of the U.S. for a variety of physical, chemical and biological indicators of environmental condition. We used the resulting data set to evaluate the importance of differing levels of macroinvertebrate taxonomic resolution in bioassessments by comparing the ability of family versus genus to detect differences among sites classified by type and magnitude of human impact and by stream size. We divided the MAH into two physiographic regions: the Appalachian Plateau where mine drainage (MD) and acidic deposition are major stressors, and the Ridge and Valley where nutrient enrichment is a major stressor. Stream sites were classified into three or four impact classes based on water chemistry and habitat. We used stream order (first to third Strahler order) in each region as a measure of stream size. Ordination, 2 × 2 chi‐square and biotic metrics were used to compare the ability of family and genus to detect differences among both stressor and size classes.

2. With one notable exception, there were only a small number of different genera per family (interquartile range = 1–4). Family Chironomidae, however, contained 123 different genera. As a result, significant information loss occurred when this group was only classified to family. The family Chironomidae did not discriminate among the predefined classes but many chironomid genera did: by chi‐square analysis, 10 and 28 chironomid genera were significant in discriminating MD and nutrient impacts, respectively.

3. Family and genus data were similar in their ability to distinguish among the coarse impacts (e.g. most severe versus least severe impact classes) for all cases. Though genus data in many cases distinguished the subtler differences (e.g. mixed/moderate impacts versus high or low impacts) better than family, differences in significance levels between family and genus analyses were relatively minor. However, genus data detected differences among stream orders in ordination analyses that were not revealed at the family level. In the ordinations, both family and genus levels of analysis responded to similar suites of environmental variables.

4. Our results suggest that identification to the family level is sufficient for many bioassessment purposes. However, identifications to genus do provide more information in genera‐rich families like Chironomidae. Genus or finer levels of identification are important for investigating natural history, stream ecology, biodiversity and indicator species. Decisions about the taxonomic level of identification need to be study specific and depend on available resources (cost) and study objectives.