bluuebunny/crossref_metadata_2025 huggingface dataset:
Sickle‐cell haemoglobin polymerization: is it the primary pathogenic event of sickle‐cell anaemia?
Authors: Vekilov Peter G.
Published: September 2007

Sickle cell anaemia is associated with a mutant haemoglobin, HbS, which forms polymers in the red blood cells of patients. The primary role of the HbS polymerization for the pathophysiology has been questioned: observations in patients and model organisms contradict deterministic scenarios of sickling crises triggered by polymerization. However, results with knock‐out sickle‐cell mice, which were cured by delaying HbS polymerization, reconfirm polymerization's primary role. To reconcile the contradictory observations, this article reviews recent findings on two steps in polymerization: homogeneous nucleation of fibres, and their growth. The fibre growth is faster by far than for any other protein ordered structure. This is due to a negligible free‐energy barrier for incorporation into a fibre, determined by an entropy gain, stemming from the release of water molecules structured around HbS. The kinetics of fibre nucleation have shown that the formation of the polymer nucleus is preceded by a metastable droplet of a dense liquid. The properties of the dense liquid are sensitive functions of solution composition, including components in micro‐ and nanomolar amounts. This mechanism allows low‐concentration solution components to strongly affect the nucleation kinetics, accounting for the high variability of the disease. These insights can potentially be utilized for control of HbS polymerization and treatment of the disease.
In vitro evidence of the inhibitory capacity of chloroquine on arginase activity in sickle erythrocytes
Authors: Iyamu Efemwonkiekie W. , Ekekezie Chiazotam , Woods Gerald M.
Published: September 2007

Increased levels of erythrocyte arginase activity are believed to play a key role in the pathogenesis of sickle cell disease (SCD). Because increased arginase activity has been implicated in the exacerbation of pulmonary hypertension in SCD, this enzyme is considered an important therapeutic target for identifying new drugs to treat and manage SCD and other inflammatory disorders. Although chloroquine (CQ) is prescribed as an anti‐malarial and anti‐rheumatoid drug, the mechanism of its anti‐inflammatory activity is largely unknown. The present study found that CQ inhibited arginase in a dose‐dependent manner, and also displayed a linear competitive inhibition on sickle erythrocyte arginase. The apparent KM values in the presence of inhibitor were considerably reduced at both physiological and slightly acidic pHs. Slope replots of the double reciprocal plots at pH 6·8 and 7·4 also indicated simple competitive inhibitory mechanism of CQ, and Ki values for CQ were within micromolar levels. To our knowledge, this is the first example of an anti‐malarial and anti‐inflammatory agent displaying competitive inhibition kinetics on arginase. The outcome of this study may provide a template for the rational design of specific agents either alone or in combination with CQ for the inhibition of arginase activity.
Toll‐like receptors: key activators of leucocytes and regulator of haematopoiesis
Authors: McGettrick Anne F. , O'Neill Luke A. J.
Published: September 2007

Toll‐like receptors (TLRs) play a critical role in the induction of the immune response to invading pathogens. The detection of pathogens by TLRs initiates a signalling cascade that results in the activation of transcription factors such as nuclear factor (NF)‐κB and interferon regulatory factors leading to the production of pro‐inflammatory cytokines and type 1 interferons. Five cytoplasmic adaptors, MyD88, Mal, Trif, TRAM and SARM, are utilized by the TLRs to activate these signalling pathways. Through the years the main focus of research has been on the activation and function of TLRs in monocytic cells. This review discusses several additional roles of TLRs. TLR activation plays a role in influencing the differentiation of haematopoietic stem cells. Their activation also prevents apoptosis in neutrophils following pathogen invasion. B cells and T cells proliferation and differentiation is influenced by TLR activation and the possible therapeutic benefits of using TLR ligands for the treatment of chronic lymphocytic leukaemia will also be discussed.
Outcome of haematopoietic stem cell transplantation for paediatric acute lymphoblastic leukaemia in third complete remission: a vital role for graft‐versus‐host‐disease/ graft‐versus‐leukaemia effect in survival
Authors: Gassas Adam , Ishaqi M Kashif , Afzal Samina , Dupuis Annie , Doyle John
Published: September 2007

Children with acute lymphoblastic leukaemia (ALL) receiving haematopoietic stem cell transplantation (HSCT) in third complete remission (CR3) are at high risk for transplant‐related mortality (TRM) and relapse. Twenty‐two consecutive children with ALL in CR3 received HSCT between January 1994 and August 2005. Ten patients died of TRM, seven patients relapsed, six did not have graft‐versus‐host disease (GVHD). Five patients were long‐term survivors, (median follow‐up, 5·8 years; range 2·9–11·7). Three‐year event‐free survival was 0·32 (95% confidence interval 0·19 and 0·59). Survivors had moderate to severe GVHD. Allowing some GVHD or exploring means of inducing GVHD should be considered in CR3 patients.
Bilan de 9 ans de suivis des déprédations de Hamsters communs (Cricetus cricetus) sur les cultures alsaciennes
Authors: Losinger I.
Published: September 2007

En France, le hamster commun (Cricetus cricetus) n’est présent que dans la plaine du Rhin. Classé nuisible jusqu’en 1993 en raison des dommages qu’il causait aux cultures, il est aujourd’hui menacé de disparition dans l’ouest de l’Europe. Il fait l’objet d’un programme de conservation à la demande du Ministère de l’Environnement depuis 1998. En raison des déprédations que quelques individus peuvent causer au printemps dans les cultures spécialisées, C. cricetus entre en conflit avec les exploitants agricoles. Pour éviter des destructions illicites, une procédure de constats de dommages a été mise en place dès 1998. Elle aboutit à la capture des animaux en cause ou à une compensation financière correspondant au manque à gagner à la récolte. En 9 ans, 48 exploitants alsaciens ont fait appel à cette procédure. 107 constats ont été dressés pour 270 terriers et 49 animaux ont été capturés et déplacés. Enfin, les dommages liés à la présence de 126 terriers ont été indemnisés pour une valeur totale d’environ 8100 EUR. Cet article met en évidence que les déprédations causées par C. cricetus s’effectuent principalement en mai, pendant une dizaine de jours, sur 3 cantons. Les campagnes d’information et la prise en compte des dommages ont contribuéà faire accepter l’espèce par la majeure partie des exploitants agricoles. Pour que cette tendance perdure, il est impératif de maintenir le système existant, mais aussi de restaurer l’habitat de l’espèce et de sensibiliser les exploitants à l’importance de ce petit rongeur alsacien.
Identification of fruit tree phytoplasmas and their vectors in Bosnia and Herzegovina
Authors: Delic D. , Martini M. , Ermacora P. , Myrta A. , Carraro L.
Published: September 2007

Surveys were carried out in autumn 2004 and spring 2005 in the traditional areas dedicated to pome and stone fruit cultivation in Bosnia and Herzegovina to assess the presence, distribution and incidence of phytoplasma diseases in fruit trees. The occurrence of psyllid vectors was also considered. The detection of phytoplasmas in plant and insect samples and their identification were carried out by symptom observations in the field, double antibody sandwich‐enzyme linked immunosorbent assay (DAS‐ELISA), nested polymerase chain reaction (nested‐PCR) and restriction fragment length polymorphism (RFLP) analyses. Laboratory analyses showed the presence of phytoplasmas belonging to: (i) 16SrX group, subgroup A (‘Candidatus Phytoplasma mali’) in 23 out of 25 apple samples, in 4 groups out of 18 of Cacopsylla picta (synonym Cacopsylla costalis) and in 2 groups out of 9 of Cacopsylla melanoneura; (ii) 16SrX group, subgroup C (‘Candidatus Phytoplasma pyri’) in 11 out of 30 pears samples and in 2 groups out of 9 of Cacopsylla pyri; (iii) 16SrX group, subgroup B (‘Candidatus Phytoplasma prunorum’) in 4 apricots, 2 peaches out of 42 stone fruit samples and in 1 group out of 14 of Cacopsylla pruni. The presence of different subtypes of Candidatus Phytoplasma mali, both in apple trees and in insects, was proven.
Surveillance for whiteflies on greenhouse roses and chrysanthemums in northern Tanzania
Authors: Ndomba O. A.
Published: September 2007

A specific monitoring survey for whiteflies was conducted in greenhouse‐grown roses and chrysanthemums in northern Tanzania from October to December 2005. The survey objectives were to appraise the suitability of yellow traps made from locally available materials, to suggest action threshold levels, and to see if the area could be considered an Area of Low Pest Prevalence. Three farms, one growing roses and two growing chrysanthemums, were sampled in the major growing areas and Pest Management Units (PMUs) of 700 m2 were formed from maps of the farmland. Twelve yellow traps were placed at intervals of 1.5 traps per PMU in the sampled farms and monitored weekly. Insects trapped included whiteflies, aphids, and occasionally fungus gnats and shore flies. The traps held insects during the period of exposure. Exposure of longer than five days in the field resulted in changes in the texture of the trap. Based on the results of these surveys, farmers are advised to take action when 1.5 whiteflies per trap in each PMU are recorded. The results show that Post Entry Plant Quarantine Inspectors could consider and recommend the area to be an Area of Low Pest Prevalence due to its tight pest management measures and routine inspections.
Computer aids for plant protection, historical perspective and future developments*
Authors: Bouma E.
Published: September 2007

Initiatives such as Videotext and forecasting models resulted in a relatively fast introduction of computer technology on to farms at the end of the 1980s. In several countries there were developments to create models for supervised control and data exchange became digital. Most models were developed for diseases that could expand very rapidly, or diseases that should be controlled regularly. In the 1990s, development of weather‐related Decision Support Systems (DSSs) began. It is important to use the optimal way to disseminate information to the target group; which can differ between or even within countries. The use of DSSs results in a lower risk of crop damage by diseases and pests, and a lower input of active substances, from the use of adjusted dosages. Future developments may include the possibility of implementing a number of DSS‐models into a Geographical Information System, which will support precision agriculture by providing adjusted spraying advice based on plot‐specific characteristics. The success of DSSs is despite its development occurring independently in a number of countries. The speed of development of these systems would have been substantially faster had there been real cooperation between countries or groups of researchers. In order to withstand funding reductions, it is necessary for the development of new DSSs that collaboration between researchers and research groups internationally increases significantly in the near future.
Empirical vs. mechanistic models for primary infections of Plasmopara viticola*
Authors: Caffi T. , Rossi V. , Cossu A. , Fronteddu F.
Published: September 2007

Plasmopara viticola, the causal agent of grapevine downy mildew, requires fungicide treatments to avoid severe yield losses, so epidemiological models have been elaborated to better manage fungicide scheduling. Primary oosporic inoculum plays a key role in epidemic development, and some of these models have been elaborated following an empirical approach to define quantitative relationships between occurrences of primary infections and weather factors influencing them. Recently, a mechanistic dynamic model was elaborated which accounts for the biological effects of weather on the different stages of the primary infection chain, from the progressive breaking of dormancy in the overwintering oospore population to infection establishment. In this work, three widely used models (3–10 rule, EPI and DMCast) were compared with this model (named UCSC model) on the basis of their theoretical approaches and their accuracy was tested against real data collected over a 9‐year period in Sardinia (Italy). The two empirical models, 3–10 and EPI, seem to be too over‐simplified to simulate correctly a complex biological phenomenon such as the sexual stage of P. viticola they lack consideration of some key stages of the infection chain and simultaneously simulate various biological events, each of which are influenced by specific weather conditions. EPI, in particular, needs specific calibrations and ongoing processes of adaptation that make its use in disease warning difficult. DMCast overcomes these problems because of its mechanistic approach; nevertheless, the empirical method used to model oospore maturation requires validations and, as in the present case, modifications before practical use. The UCSC model, due to its fully mechanistic approach, does not present this problem and provides accurate dynamic simulations of the sexual stage of P. viticola, with a high degree of detail and requiring neither calibrations nor corrections.
The application of artificial neural networks in plant protection*
Authors: Peacock L. , Worner S. , Pitt J.
Published: September 2007

Artificial neural networks are powerful predictive tools that have the ability to detect and approximate non‐linear relationships from the data. In an explorative analysis, artificial neural networks were used to predict the geographic distribution of groups of polyphagous plant pests. Using climate variables as predictors, artificial neural network models were compared with binary logistic models for predicting insect distribution. Using bootstrapping, artificial neural networks were shown to predict insect presence and absence significantly better than the binary logistic regression models. Results from the study suggest that artificial neural networks have the potential for application in many areas of plant protection and biosecurity.
A‐scab (Apple‐scab), a simulation model for estimating risk of Venturia inaequalis primary infections*
Authors: Rossi V. , Giosuè S. , Bugiani R.
Published: September 2007

A‐scab (Apple‐scab) is a dynamic simulation model for Venturia inaequalis primary infections on apple. It simulates development of pseudothecia, ascospore maturation, discharge, deposition and infection during the season based on hourly data of air temperature, rainfall, relative humidity and leaf wetness. A‐scab produces a risk index for each infection period and forecasts the probable periods of symptoms appearance. The model was validated under different epidemiological conditions: its outputs were successfully compared with daily spore counts and actual onset and severity of the disease under orchard conditions, and neither corrections nor calibrations have been necessary to adapt the model to different apple‐growing areas. Compared to other existing models, A‐scab: (i) combines information from literature and data acquired from specific experiments; (ii) is completely ‘open’ because both model structure and algorithms have been published and are easily accessible; (iii) is not written with a specific computer language but it works on simple‐to‐use electronic sheets. For these reasons the model can be easily implemented in the computerized systems used by warning services.
Transboundary system for grapevine downy mildew risk evaluation on a territorial scale (P. Rada project)*
Authors: Dalla Marta A. , Gani M. , Cicogna A. , Dietrich S. , Orlandini S. , Santorelli E.
Published: September 2007

A wide and homogenous viticultural area traverses the border between Friuli Venezia Giulia (Italy) and the western part of Slovenia. Despite similar agricultural, climatic and geographical conditions on each side of the border, the management of agricultural activities and, in particular, the organization of phytosanitary campaigns is carried out separately and differently between the two countries incurring a waste of money, time and energy. The project P. Rada (EU Interreg IIIA Italy Slovenia 2000–06) was set up with the aim of establishing a common expert agrometeorological system to evaluate the development of Plasmopara viticola on a territorial scale. The required agrometeorological data are collected by a network of weather stations and spatially interpolated in a grid with a resolution of 500 × 500 m. The spatial dataset obtained is integrated with rainfall images processed by a polarimetric radar located in Fossalon di Grado (Gorizia, Italy). Once the territorial dataset has been completed, data are used to feed two agrometeorological models: SWEB, for the estimation of leaf wetness, and PLASMO for the simulation of grapevine downy mildew. The main output of the system is represented by meteorological (temperature, rainfall, leaf wetness) and epidemiological (total and current number of infections, days for the outbreak of the current infection) maps capable of supplying end users with detailed information useful for planning and management of grapevine protection activity.
The importance of forecasting and warning systems in implementation of integrated pest management in apple orchards in Turkey*
Authors: Atlamaz A. , Zeki C. , Uludag A.
Published: September 2007

Integrated Pest Management (IPM) has been widely implemented in apple orchards in various regions of Turkey. Between 1995 and 1999, in Central Anatolia and the Aegean Region, apple scab (Venturia inequalis) and codling moth (Cydia pomonella) were key pests, and implementation of pest control was based on forecasting and warning systems. During the project, orchards in which IPM was implemented and in which farmers applied conventional practices were compared. In nine provinces in which IPM projects were carried out in 1999, the damage due to codling moth was 0–1.3% in IPM orchards while it was 0.4–21.8% in nearby non‐IPM orchards. It is clear that damage did not reach the acceptable threshold level of 2% in any of the IPM orchards, while damage was much higher than the threshold in conventionally‐farmed orchards. The number of fungicide applications against apple scab decreased to 5–6 applications from 10–15 applications in the Eğirdir district of the Isparta Province in 1996 as a result of IPM implementation. No insecticides were applied against codling moth in IPM orchards in the Nigde Province in 1998 and 1999 because population levels of the pest were low and under the economic threshold. Apple producers received training and 1200 producers from Central Anatolia became experts in IPM for their own orchards, learning to make appropriate decisions about pest control. The Apple IPM Guideline was prepared and disseminated. In Turkey modern equipment for forecasting and warning systems was employed and, in the last decade, forecasting and warning networks have been improved. Computer‐based systems have increased the speed and accuracy of forecasting as well as decreasing its costs. A computerized national forecasting network in apple orchards now transmits data from the field to system headquarters automatically. The national forecasting network has been expanded and covered 12 208 800 apple trees in 34 provinces in 2006, using 115 electronic forecasting and warning stations.
Multi‐scale modelling of infection pressure from Phytophthora infestans*
Authors: Skelsey P. , Van Der Werf W. , Kessel G. J. T. , Rossing W. A. H. , Holtslag A. A. M.
Published: September 2007

Management of potato late blight could benefit from prediction of the risk posed to potato fields from external inoculum sources of Phytophthora infestans. Influx of inoculum depends on a complex interplay of population biological, atmospheric and spore survival processes, and is difficult to predict. This research aims at building tools for such prediction. BLIGHTSPACE is a spatio‐temporal model (parameterized for potato late blight) that has been developed and utilized to study the progress of epidemics in individual fields and networks of fields. A quasi‐Gaussian plume model was developed to provide long‐range transport of spores within BLIGHTSPACE. Numerical results compared favorably with experimental data. A further submodel for the survival of spores during long‐range transportation has been added. Integration of these three submodels will create an experimental arena for comparing control options for potato late blight.
AgmedaWin – a tool for easy and flexible management of meteorological data*
Authors: Keil B. , Kleinhenz B.
Published: September 2007

Decision support systems in plant protection need plausible and complete meteorological data as the main input. While meteorological data are provided by the German meteorological service, several states in Germany have built up their own meteorological networks. These states use the software AgmedaWin to import, manage, present, evaluate and export the measured data. At the core of the program is a flexible import module which facilitates the import of files in different formats from all types of meteorological stations by using import profiles to describe the structure of the files. Several algorithms are integrated in AgmedaWin to ensure plausibility and completeness of the data. The program also includes a module to compare the data of neighbouring stations. AgmedaWin is being used so far in seven states of Germany since 2005. With an XML–based export interface the data are transferred from AgmedaWin to the Internet system ISIP (http://www.isip.de) in which all data are stored and used as input for decision support systems. Furthermore the unprocessed meteorological data can be evaluated in ISIP or downloaded as files in different formats by external users.
Prediction studies supported by computer on potato late blight in central Anatolia in Turkey*
Authors: Cakir E.
Published: September 2007

Prediction of potato late blight epidemics, caused by Phytophthora infestans (Mont) de Bary, was studied in three different villages of Bolu Province having large potato growing areas with the Winstel and Ullrich Schrodter models in the years 2002–05. During these years, a late blight outbreak was observed only in 2005 with the disease being less apparent in the other years. The Ullrich Schrodter model was found to poorly predict potato late blight epidemics in 2005. The Winstel model gave first warnings too early but correctly predicted late infections. Both the A1 and A2 mating types were found in Central Anatolia for the first time, in Bolu province.
CERCBET 3 – a forecaster for epidemic development of Cercospora beticola*
Authors: Racca P. , Jörg E.
Published: September 2007

Cercospora beticola is the most prevalent and damaging fungal disease in German sugar beet growing. Control strategies are based on action thresholds. A model has been developed which forecasts epidemic development (expressed as disease incidence) and signals when action thresholds are overridden. The plot‐specific model, CERCBET 3 uses as input meteorological parameters (temperature, relative humidity), easily accessible agronomic field characteristics and a single recording of C. beticola disease incidence. Extensive validation in 2001–03 showed that, in 80–95% of the cases, CERCBET 3 correctly forecasted the dates when thresholds were overridden. Cultivar diversity in German sugar beet growing is increasing, thus a module has been included into CERCBET 3 which reflects susceptibility to C. beticola by introducing a sporulation factor. In some cases a second or even third fungicide treatment could be necessary to control Cercospora leaf spot and so a further module which models fungicide efficacy has been elaborated. CERCBET 3 is available for sugar beet growers in an interactive form on the Internet platform ISIP, which is provided by the governmental crop protection services of Germany.
Control of Colorado Potato Beetle with the SIMLEP Decision Support System*
Authors: Jörg E. , Racca P. , Preiß U. , Butturini A. , Schmiedl J. , Wójtowicz A.
Published: September 2007

The Colorado Potato Beetle (Leptinotarsa decemlineata) is a serious threat in potato‐growing areas in Europe. Control requires a high insecticide input and meanwhile L. decemlineata has developed resistance to all commonly used insecticides. In order to establish an integrated pest management system a temperature‐driven decision support system (SIMLEP DSS) has been elaborated and consists of two modules. SIMLEP 1 is a regional forecasting model for the first occurrence of hibernating beetles and the start of egg laying. SIMLEP 3 is a field–specific model which forecasts the occurrence of the developmental stages of L. decemlineata. From 1999 to 2004 SIMLEP 3 was validated in Germany, Austria, Italy and Poland. In about 90% of cases SIMLEP 3 correctly predicted the periods of maximum egg laying and young larval occurrence, which are the optimal periods for field assessments and treatments with conventional and biological insecticides. SIMLEP 3 is used in practice in Germany and Austria on a large scale and in the western part of Poland. The SIMLEP DSS contributed a lot to the improvement of farmers’L. decemlineata control measures.
A decision support system for Fusarium head blight on small grain cereals*
Authors: Rossi V. , Giosuè S. , Terzi V. , Scudellari D.
Published: September 2007

A DSS was elaborated to determine the level of risk for mycotoxin accumulation in small grain cereals during the growing season and to support different management actions along the cereal production chain. The DSS is based on a discriminant analysis carried out on a representative data set on the presence of deoxinivalenol in winter‐sown bread wheat, durum wheat and barley grown in different areas of Emilia‐Romagna (northern Italy) between 2002 and 2004. Three to five levels of proneness to Fusarium head blight were defined for six influencing factors (weather conditions, growing area, host species and variety, previous crop and type of soil tillage before sowing), each level having its own coefficient, and linearly combined in an equation of risk (R). A value of R can be then calculated for any plot using information at both regional (weather conditions and growing area) and plot‐specific (host and cropping practices) levels. R ranges between −3.86 and 4.43 with four risk levels: low (R  –2), intermediate (–2 < R  –0.44), high (–0.44 < R  1.2), and very high (R > 1.2). Different management actions are suggested based on the level of R of the plot. The DSS was satisfactorily validated using data from many plots other than those used in its elaboration.
SIMPEROTA 1/3 – a decision support system for blue mould disease of tobacco*
Authors: Racca P. , Kleinhenz B. , Jörg E.
Published: September 2007

Blue mould (Peronospora tabacina) is the most serious threat to German tobacco crops. In order to efficiently control the disease whilst minimizing the risk of nontolerable fungicide residue levels on tobacco leaves, a decision support system has been developed which optimizes the timing of fungicide treatments. The DSS consists of two models, SIMPEROTA 1, which forecasts the dates of blue mould first appearance and SIMPEROTA 3 which forecasts the dates of fungicide applications. Crucial biological processes are included in the models (infection, mycelium growth, sporulation and spore release). Input parameters are temperature, relative humidity and leaf wetness recorded on an hourly basis. Validation with data from 2003 and 2006 showed that SIMPEROTA 1 gave satisfying results. The model is suitable for practical use and can be employed for steering monitoring efforts of extension services and for the timing of the first fungicide treatment. SIMPEROTA 3 gives advice on follow‐up treatments and the length of spraying intervals, but this model needs to be validated before being introduced into practice.
PUCREC/PUCTRI – a decision support system for the control of leaf rust of winter wheat and winter rye*
Authors: Räder T. , Racca P. , Jörg E. , Hau B.
Published: September 2007

During a three‐year project from 2003 to 2006, two models have been developed to predict leaf rust (Puccinia recondita and P. triticina) occurrence and to simulate disease incidence progress curves on the upper leaf layers of winter rye (PUCREC) and winter wheat (PUCTRI). As input parameters the models use air temperature, relative humidity and precipitation. PUCREC and PUCTRI firstly calculate daily infection favourability and a cumulative infection pressure index and, in a second step, disease incidence is estimated. An ontogenetic model (SIMONTO) is used to link disease predictions to crop development. PUCREC and PUCTRI have been validated with data from 2001 to 2005. Both models give satisfactory results in simulating leaf rust epidemics and forecasting dates when action thresholds for leaf rust control are exceeded.
Eucablight – collating and analysing pathogenicity and resistance data on a European scale*
Authors: Hansen J. G. , Colon L. T. , Cooke D. E. L. , Lassen P. , Nielsen B. , Cooke L. R. , Andrivon D. , Lees A. K.
Published: September 2007

The Concerted Action on potato late blight ‘Eucablight’ (http://www.eucablight.org) was launched in 2003 to promote collaboration between researchers across Europe and to collate the previously fragmented data on host resistance to late blight and characterization of populations of its causal agent, Phytophthora infestans. Fundamental to the project was the development of standardized protocols, databases and data collection tools with which data from across Europe could be centralized. The ultimate aim was to capitalize on the vast resource of data available in order to allow a pan‐European analysis to be conducted. The P. infestans database is currently populated with information relating to over 15 000 isolates from 20 European countries. The host resistance database holds primary disease data, and derived statistics, from more than 50 field trials assessing mainly foliage blight resistance. The use of five standard cultivars in these trials facilitated the comparison of resistance information across years and regions. The host database is structured, and made accessible, in such a way that DSS builders can access the model parameters they need to construct locally adapted forecasting systems. In this presentation we describe the database and the data analysis tools that have been developed in this project and how they are directly applicable to other host‐pathogen systems.
Interceptions of harmful organisms during import inspections of cut flowers in the Netherlands: an empirical and theoretical analysis of the ‘reduced checks’ system*
Authors: Surkov I. V. , Van Der Werf W. , Van Kooten O. , Lansink A. G. J. M. Oude
Published: September 2007

As of January 1st 2005, a system of reduced checks for phytosanitary inspections of certain plants and plant products imported into the European Union (EU) is in place. Under this system, plants and plant products satisfying special criteria may be inspected with a reduced frequency. These criteria are based on EU‐wide data on historical volumes of import and interceptions of harmful organisms in particular products. The objective of this paper is two‐fold. Firstly, the paper analyses whether proportions of interceptions of harmful organisms associated with cut flowers imported into the Netherlands – the largest EU importer of cut flowers – support the application of reduced checks for certain genera and trades (commodity‐exporting country combinations) of cut flowers. Secondly, the paper analyses how effective the reduced checks system is in minimizing the expected costs of introduction of harmful organisms in the EU. For that, a theoretically optimal system for allocating inspection effort to commodities is described. Using an illustrative example and stochastic simulations, the expected costs of introduction of harmful organisms under the theoretically optimal system and the current system of reduced checks are compared. Examination of interceptions of harmful organisms supports application of reduced checks for most genera and trades of cut flowers in the Netherlands. The results of stochastic simulations show that reduced checks may not minimize the expected costs of introduction of harmful organisms into the EU. Accounting for possible economic impacts of harmful organisms in determining the frequencies of reduced checks may help optimize the current system.
Exotic Pest Information Collection and Analysis (EPICA) – gathering information on exotic pests from the World Wide Web*
Authors: Bateman M. , Brammer C. , Thayer C. , Meissner H. , Bailey W.
Published: September 2007

This paper describes the Exotic Pest Information Collection and Analysis (EPICA) project, a cooperative effort of the United States Department of Agriculture's (USDA) Center for Plant Health Science and Technology (CPHST) and the National Science Foundation's Center for Integrated Pest Management (CIPM). The EPICA team identifies, archives, evaluates, and communicates relevant information about exotic plant pests from around the world that potentially threaten US agriculture and the environment. The goal of the EPICA project is to provide key groups within USDA's Plant Protection and Quarantine (PPQ) with regular updates of vital pest information to enable a proactive safeguarding approach.
EBA Cement. A Practical system for all Cementation
Authors: HENDRA L. PETER
Published: September 2007

A survey of ihe development and testing and physicul properics of an EBA cementing and lining system applied to the practical requirements of the Dental Surgeon.
Bacteriology and Endodontics
Authors: MELVILLE T. H.
Published: September 2007

Based on a lecture given to the Annual Provincial Meeting of the British Society of Endodontists, on 2nd October, 1971.
New Method of Measuring the Exact Length of Root Canal Instruments
Authors: GULDENER P. H. , IMOBERSTEG C.
Published: September 2007

This article was first published in Schweiz Mschr. Zahnheilk (1971), 82, 280.
Antibody formation and cell‐mediated immunity to dog pulp tissue altered by eight endodontic sealers via the root canal1
Authors: BLOCK R. M. , LEWIS R. D. , SHEATS J. B. , BURKE S. H. , FAWLEY J.
Published: September 2007

The authors wish to thank Dr James Wolf, Daniel Green, Mr Buddy Hudson, and the entire staff of the Animal Surgical Research Laboratory, McGuire VA Hospital, Richmond, Virginia. This project was supported by Animal Surgical Research Funds, McGuire Veterans Hospital, Richmond, Virginia.
Distribution of TiO2 after partial and total pulpectomy
Authors: LEHMANN R. R. , SLUKA H.
Published: September 2007

The expert help provided by Mrs E. Gräfin von Plettenberg, Miss M. Knaut, S. Nehmzow, and G. Lau is gratefully acknowledged. Our thanks are due to Mrs D. Krüger for excellent photographic work.
Vital pulpectomy—an unpredictable procedure1
Authors: FORD T. R. PITT
Published: September 2007

I should like to thank in particular Messrs S. P. Kariyawasam and S. P. Metcalfe for staining the histological sections, Professor A. H. R. Rowe for his valuable advice, and Amalgamated Dental Ltd for their generous financial support.
The use of sodium hypochlorite as a general endodontic medicament
Authors: MENTZ T. C. F.
Published: September 2007

At the University of Nijmegen NaOCl solution is now used as an irrigant and a universal medicament in root canal therapy. The use of conventional intracanal medicaments between appointments has been abandoned. A 2.5–3.0 per cent NaOCl solution, pH 11–12 at 30–37°C is used in combination with scrupulous mechanical preparation, and is a successful basis for subsequent obturation.
Endodontics in general practice—a retrospective survey
Authors: NELSON I.A.
Published: September 2007

Thanks are due to Professor A. H. R. Rowe and members of the staff of the Department of Conservative Dental Surgery, Guy's Hospital Dental School, for their encouragement and guidance during the preparation of this paper.

Thanks are also due to the secretarial staff of the Department and to the staff of the Departments of Medical Illustration and Dental Photography for their invaluable technical assistance.
Sealing quality of a newly designed root canal filling material following apicectomy compared with amalgam and heat‐sealed gutta‐percha
Authors: NEGM M. M. , GRANT A. A. , COMBE E. C.
Published: September 2007

A newly designed root canal filling material, prepared by coating silver cones with guttapercha, was compared with heat‐sealed gutta‐percha and amalgam to evaluate its effectiveness as a root canal sealer using a dye penetration method in vitro. The study indicated that silver‐percha cones are more effective in their sealing ability than retrograde amalgam and heat‐sealed gutta‐percha. The heat‐sealed gutta‐percha was shown to provide an inferior seal.
A root canal disinfectant with reduced formaldehyde concentration. Cytotoxicity and anti‐microbial effectiveness under clinical conditions in monkey teeth
Authors: SIMON M. , MULLEM P. J. VAN , LAMERS A. C.
Published: September 2007

Four formol‐alcohol compounds of different formaldehyde and ethanol concentrations (FA 3·15/20, FA 6/15, FA 8·75/30 and FA 8·75/60), were studied for anti‐microbial effectiveness and periapical tissue reaction in a clinical experiment in monkeys.

Using FA 6/25, the periapical inflammatory reaction was minimal and anti‐microbial effectiveness appeared to be sufficient in infected teeth at the end of a 7 day period. Five weeks after the 1 week dressing period the periapical tissue reaction had returned to the level of the controls.
The value of the bacteriological culture in endodontics. II. The bacteriological flora of endodontic specimens
Authors: STOBBERINGH E. E. , EGGINK C. O.
Published: September 2007

A correlation was found between the presence of micro‐aerophilic micro‐organisms and the periapical radiolucency in teeth with a necrotic closed pulp.

No correlation was found between micro‐aerophilic, anaerobic and aerobic bacteria, the presence of a periapical radiolucency and the clinical diagnosis. (This in contrast to the results of Winkler & Van Amerongen 1959).

The presence of a periapical radiolucency alone did not permit any conclusion about the bacteriological status. The possible pathogenic role of the isolated bacteria has to be elucidated further before any conclusion is possible.

In the absence of a periapical radiolucency the chance of a positive bacteriological result is low (28 per cent) and justifies the omission of bacteriological cultures.
Fluoride as the possible cytotoxic component of Silicap. 1. Fluoride release
Authors: MERYON SYLVIA D. , SMITH A. J. , TOBIAS ROSALIND S. , BROWNE R. M.
Published: September 2007

This study was supported in part by a grant from the DHSS, No. R/E 1050/105, and the Amalgamated Dental Company. The authors are grateful to Mrs G. Smith, Mr P. Stephens and Mrs G. Bowen for skilled technical assistance; to Dr Buchan, Department of Medical Microbiology, for the initial supply of fibroblasts and to Dr Perris, Department of Biological Sciences, University of Aston, for the use of the Coulter counter. In addition, the help of the Photographic Unit in preparing figures is acknowledged.
EDTA — time for re‐evaluation?
Authors: DOW PIERRE R.
Published: September 2007

Abstract. The use of EDTA as a demineralizing solution for facilitating instrumentation of fine canals is examined. Although the chelation occurring on the dentine is a simple chemical reaction, there is little evidence that it is effective in the clinical situation of a fine canal.
A comparison of fluoride release from three glass ionomer cements and a polycarboxylate cement
Authors: MERYON SYLVIA D. , SMITH ANTONY J.
Published: September 2007

Abstract. This study investigated the fluoride release from three glass ionomer cements, ASPA, ChemFil and ChemBond, and a fluoride‐enriched polycarboxylate cement, Poly‐F Plus, using a simulated model cavity system. ChemFil released considerably more fluoride than the other materials at all the time intervals investigated. The release from ASPA was greater than that for either ChemBond or Poly‐F Plus. Release from ChemFil and ASPA was of a similar order to a silicate cement investigated previously and it is expected that this release should confer some protection against secondary caries.
Pulpal effects of glass ionomer cements
Authors: PLANT C. G. , BROWNE R. M. , KNIBBS P. J. , BRITTON A. S. , SORAHAN T.
Published: September 2007

Summary. The incidence of pulpal damage beneath cavities filled with ASPA, Chemfil and Chembond was studied in class I cavities in human premolar teeth after 1–10 days, 11–30 days, and 31 or more days. Cavities filled with Kalzinol or zinc oxide/eugenol acted as controls. All glass ionomer cements were accompanied by more pulpal damage than controls, but Chemfil was associated with the least changes. Bacteria were demonstrated at the material/cavity wall interface in a number of cavities with all materials, although no significant correlation was demonstrated between them and pulpal inflammation. The use of a base is recommended in cavities where large numbers of previously unaffected dentinal tubules are present.
Apical leakage associated with three obturation techniques in large and small root canals
Authors: BEATTY RICHARD G. , ZAKARIASEN KENNETH L.
Published: September 2007

Abstract. This study evaluated the apical leakage associated with three methods of root canal obturation; these were laterally condensed gutta‐percha with and without custom‐fined master cones and a single silver point technique. Two different sized canals were used. An analysis of linear dye leakage was performed for large canals and a technique of dye recovery and spectrophotometric analysis was used to examine the volume of leakage in both large and small canals.

Laterally condensed gutta‐percha with custom‐fitted master cones resulted in less volume of apical leakage than did non‐custom‐fitted laterally condensed gutta‐percha or silver cones.
The endodontic management of a replanted avulsed tooth with severe root resorption — a case report
Authors: CAMERON JEFFREY A.
Published: September 2007

Summary. . The replanted upper central incisor of a 9‐year‐old patient suffered severe inflammatory root resorption. The resorptive process was halted by the removal of necrotic pulp tissue followed by dressings of calcium hydroxide. The root canal was debrided using indirect ultrasound and irrigated with 3 per cent sodium hypochlorite solution. Technical difficulties complicated root canal obturation.
Conservative endodontic therapy following the removal of a ‘globulomaxillary cyst’— a case report and review of literature
Authors: KELLEHER M. G. D.
Published: September 2007

Summary. A cyst was removed from the right maxilla and diagnosed by a hisiopathologist as being ‘globulomaxillary’ in origin. The area failed to heal until conservatrve endodontic therapy was undertaken for three adjacent teeth. Prior to the enucleation the vitality of these teeth had only been tested by the response to ethyl chloride. On its own, this test is considered to be inadequate for the confirmation of ‘vital’ teeth which is necessary if the cyst is to be diagnosed as ‘globulomaxillary’. Very grave reservations already exist in relation to the concept of ‘globulomaxillary cysts’ and the term is again deprecated because the adjacent teeth were non‐vital and the area only healed following endodontic therapy.

Calcium hydroxide was used as an intermediate dressing and one tooth was obturated using a combination of calcium hydroxide and amalgam.

The patient had also had radiotherapy following the removal of a medulloblastoma 12 years previously.
The position and topography of the apical canal constriction and apical foramen
Authors: DUMMER PAUL M. H. , McGINN JOHN H. , REES DAVID G.
Published: September 2007

Abstract. Two hundred and seventy extracted human teeth of unknown age were evaluated for apex to foramen and apex to constriction distances, in addition the topography of the apical portion of the root canal was studied under × 20 magnification. The mean A–F distance was 0.38 mm and the mean A–C distance 0.89 mm, although it must be stressed that a wide range of values was observed. Four distinct types of apical constriction were routinely found, whilst a proportion of canals were apparently blocked. The study confirms the view that it is impossible, with complete certainty, to establish the position of the apical canal constriction during root canal therapy, but indicates that a combination of methods might be more successful than reliance on one.
Allergic skin reactions provoked by a root canal disinfectant with reduced formaldehyde concentration
Authors: SIMON M. , VAN MULLEM P. J. , LAMERS A. C.
Published: September 2007

Abstract. The immunogenic potential of a root canal disinfectant (FA 6/25) with a reduced formaldehyde concentration (one‐third of that in Formocresol) was studied after application to one incisor tooth per guinea‐pig, both presensitized and non‐presensitized. Skin reaction after occlusive patch testing was studied. Several indications were found that the disinfectant caused an allergic reaction.
The teaching of endodontics in the Lisbon Higher School of Dental Medicine1
Authors: DE ALMEIDA C. M.
Published: September 2007

Summary. Endodontics was included in the curriculum as an independent discipline when the training of dentists began in Portuguese dental schools in 1977. The concepts, objectives, teaching methods, student's requirements and their clinical activity are described.
The effect of different files on the preparation shape of severely curved canals
Authors: ELDEEB MAHMOUD E. , BORAAS JOANN C.
Published: September 2007

Summary. Five endodontic files from different manufacturers (Kerr K‐flex, Unitek K‐file, Star Flex‐o‐file, Union Broach Hedstrom, and Union Broach K‐file) were used to prepare 100 simulated curved canals in clear resin blocks. The effect on packing of debris, instrumentation time, and final preparation shape was compared. The least instrumentation time occurred with the Hedstrom file, which also tended not to pack debris at the apes: compared with all the other instruments. The Hedstrom and Flex‐o‐file resulted in significantly less canal zipping than the Union Broach K‐file at file size 25. At sizes 30 and 35, the differences between files were not significant. Regardless of file type, Canal zipping increased significantly with the increase in file size, especially from size 30 to 35 files.
Posterior endodontic surgery: anatomical considerations and clinical techniques
Authors: GUTMANN JAMES L. , HARRISON JOHN W.
Published: September 2007

Summary. The use of endodontic surgery enhances the retention of many teeth which would otherwise be extracted. This applies to the posterior region as well as the anterior region of the oral cavity. However, because of variations in regional and radicular anatomy in the posterior, and the need to establish adequate access through proper flap design in a more confined area, it is necessary that the practitioner should have a thorough understanding of the principles of posterior endodontic surgery.
Resorption related to orthodontics and some morphological features of the periodontal microvascular bed
Authors: SIMS M. R. , WEEKES W. T.
Published: September 2007

Summary.Human premolars were obtained for sectioning following rapid maxillary expansion to observe the pattern of resorprion and cementum deposition. Some sections were demineralized and examined by light microscopy, while the root surface of adjacent sections were observed in the scanning electron microscope. The pattern of repair by cementum was noted and found to differ from normal cementum.

In addition, the vascular pattern of the periodontal ligament in rat molars has been studied by methacrylate perfusion techniques. The vasculature of the inter‐radicular area differed from that over die remaining root surface because of the presence of a dense plexus of large venous vessels. It is considered that there may be a relationship between vascular architecture and the processes of cementum deposition and root resorption.