Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi).

BACKGROUND: Intermittent preventive antimalarial treatment in infants (IPTi) is currently evaluated as a malaria control strategy. Among the factors influencing the extent of protection that is provided by IPTi are the transmission intensity, seasonality, drug resistance patterns, and the schedule of IPTi administrations. The aim of this study was to determine how far the protective efficacy of IPTi depends on spatio-temporal variations of the prevailing incidence of malaria. METHODS: One thousand seventy infants were enrolled in a registered controlled trial on the efficacy of IPTi with sulphadoxine-pyrimethamine (SP) in the Ashanti Region, Ghana, West Africa (ClinicalTrial.gov: NCT00206739). Stratification for the village of residence and the month of birth of study participants demonstrated that the malaria incidence was dependent on spatial (range of incidence rates in different villages 0.6-2.0 episodes/year) and temporal (range of incidence rates in children of different birth months 0.8-1.2 episodes/year) factors. The range of spatio-temporal variation allowed ecological analyses of the correlation between malaria incidence rates, anti-Plasmodium falciparum lysate IgG antibody levels and protective efficacies provided by IPTi. RESULTS: Protective efficacy of the first SP administration was positively correlated with malaria incidences in children living in a distinct village or born in a distinct month (R2 0.48, p < 0.04 and R2 0.63, p < 0.003, respectively). Corresponding trends were seen after the second and third study drug administration. Accordingly, IgG levels against parasite lysate increased with malaria incidence. This correlation was stronger in children who received IPTi, indicating an effect modification of the intervention. CONCLUSION: The spatial and temporal variations of malaria incidences in a geographically and meteorologically homogeneous study area exemplify the need for close monitoring of local incidence rates in all types of intervention studies. The increase of the protective efficacy of IPTi with malaria incidences may be relevant for IPTi implementation strategies and, possibly, for other malaria control measures

Systemic bacteraemia in children presenting with clinical pneumonia and the impact of non-typhoid salmonella (NTS).

BACKGROUND: The diagnosis and antimicrobial treatment of pneumonia in African children in the absence of diagnostic means such as x-ray facilities or microbiological laboratories relies primarily on clinical symptoms presented by the patients. In order to assess the spectrum of bacterial pathogens, blood cultures were performed in children fulfilling the clinical criteria of pneumonia. METHODS: In total, 1032 blood cultures were taken from children between 2 months and 5 years of age who were admitted to a rural hospital in Ghana between September 2007 and July 2009. Pneumonia was diagnosed clinically and according to WHO criteria classified as "non-severe pneumonia" and "severe pneumonia" ("severe pneumonia" includes the WHO categories "severe pneumonia" and "very severe pneumonia"). RESULTS: The proportion of bacteriaemia with non-typhoid salmonella (NTS) was similar in children with pneumonia (16/173, 9.2%) compared to children hospitalized for other reasons (112/859, 13%). NTS were the predominant organisms isolated from children with clinical pneumonia and significantly more frequent than Streptococcus pneumoniae (8/173, 4.6%). Nine percent (9/101) of children presenting with severe pneumonia and 10% (7/72) of children with non-severe pneumonia were infected with NTS. Nineteen out of 123 NTS isolates (15%) were susceptible to aminopenicillins (amoxycillin/ampicillin), 23/127 (18%) to chlorampenicol, and 23/98 (23%) to co-trimoxazole. All NTS isolates were sensitive to ceftriaxone and ciprofloxacin. CONCLUSION: In Sub-saharan Africa, sepsis with NTS should be considered in children with symptoms of pneumonia and aminopenicillins might often not be the adequate drugs for treatment

Migrations-Manual

Handreichung zur Sicherung und zum Export einer RefWorks-Datenbank (Legacy RefWorks), um diese bestmöglich in andere Literaturverwaltungsprogramme überführen zu können, bevor mit Auslaufen der Campuslizenz der Zugriff auf die erstellte Datenbank erlischt. Es werden ebenfalls Hinweise gegeben, wie mit Rückgriff auf eine RefWorks-Datenbank erstellte eigene Dokumente (via Write-N-Cite, One-Line/Cite oder BibTeX) für die weitere Bearbeitung aufbereitet werden können

Klimawandel in der Lüneburger Heide – Kulturlandschaften zukunftsfähig gestalten

Klimawandel in der Lüneburger Heide – welche Veränderungen kommen auf uns zu? Wie können wir uns darauf einstellen? Die durchgeführten Klimaprojektionen für das Modellgebiet der Lüneburger Heide haben zum Ergebnis, dass zur Mitte des 21. Jahrhunderts für alle Jahreszeiten höhere Mitteltemperaturen zu erwarten sind. Im Winter steigen die Temperaturen jeweils am stärksten, im Frühjahr am geringsten. Eis- und Frosttage treten deutlich seltener auf, während im Sommer Tage mit extremen Temperaturen häufiger vorkommen und starke Niederschläge noch an Intensität zunehmen. Dies alles wird Auswirkungen haben auf Ökosysteme und Stoffkreisläufe, auf Flora, Fauna und die Menschen in der Region. Auf den überwiegend sandigen Böden des Kulturlandschaftsraumes Lüneburger Heide befinden sich ökologisch besonders wertvolle Nieder- und Hochmoore, Heideflächen und zahlreiche grundwassergespeiste Heidebäche. Das Gebiet ist andererseits durch großflächige land- und forstwirtschaftliche Nutzungen geprägt. Im Rahmen von KLIMZUG-NORD wurden im Modellgebiet Lüneburger Heide im Wesentlichen die Auswirkungen des Klimawandels auf die Handlungsfelder Wasserwirtschaft, Land- und Bodennutzung, Naturschutz und Kommunikation beforscht und Anpassungsmaßnahmen entwickelt. Dabei bleiben eine umweltschonende Landbewirtschaftung und ein leistungsfähiger Naturhaushalt unter Klimawandelaspekten eine gültige Zielvorstellung – gerade auch angesichts der zu erwartenden zunehmenden Konkurrenz um die Ressource Wasser. Mit diesem Beitrag wollen wir unser gängiges Handeln kritisch hinterfragen, über erzielte Ergebnisse aus den Klimaanpassungsprojekten berichten und Handlungsoptionen aufzeigen

Oligonucleotide batch quality has a limited impact on quantitative real-time PCR

Quantitative real-time PCR (qPCR) is currently the method of choice for sequence specific quantification of DNA. The design of oligonucleotide primers and probes is essential. Oligonucleotides are available not only from different manufacturers but also in different purity grades. Three event-specific qPCR methods for the quantification of genetically modified organisms (GMOs) were chosen, namely for maize NK603, maize MIR604 and soya 356043 to assess a possible impact of the choice of manufacturer and purity grade of oligonucleotides on qPCR results. Coefficients of determination (R2), slopes and y-intercepts obtained from calibration curves using oligonucleotides of different suppliers and purity grades were evaluated statistically and compared. The same oligonucleotides were used to quantify the DNA content of GMO in Certified Reference Materials (CRMs) ERM-BF415f (maize NK603), ERM-BF423d (maize MIR604) and ERM-BF425d (soya 356043) by qPCR. All calibration curves for all events and all suppliers and purity grades were highly linear. The lowest R2 observed in this study was 0.997. No considerable differences were observed for mean R2 from calibration curves generated with oligonucleotides from different suppliers and purity grades. For mean slopes and mean y-intercepts of calibration curves group distribution patterns per PCR target were observed. However, for all PCR targets no tendency in performance between suppliers and purity grades could be identified. A statistical comparison of slopes was performed testing the equivalence of all analysed calibration curves. Though slopes were significantly different for some of the investigated PCR targets, no effect of oligonucleotide supplier or purity grade could be shown. Also, the estimated GMO content for the three CRMs ERM-BF415f, ERM-BF423d and ERM-BF425d using different sources and purity grades of oligonucleotides were in agreement with each other with relative standard deviations below 4 %. With this study we demonstrate that the choice of oligonucleotide manufacturer and purity grade has little impact on qPCR measurement results. Consequently, we suggest that no additional uncertainty component has to be accounted for in the uncertainty budget of qPCR measurement results. However, oligonucleotide quality can have an effect on qPCR calibration especially in qPCR methods that tend to be less robust.JRC.D.2-Standards for Innovation and sustainable Developmen

Evaluation of plasmid and genomic DNA calibrants used for the quantification of genetically modified organisms

The reliable quantification of genetically modified organisms (GMOs) by real-time PCR requires, besides thoroughly validated quantitative detection methods, sustainable calibration systems. The latter establishes the anchor points for the measured value and the measurement unit, respectively. In this paper, the suitability of two types of DNA calibrants, i.e. plasmid DNA and genomic DNA extracted from plant leaves, for the certification of the GMO content in reference materials as copy number ratio between two targeted DNA sequences was investigated. The paper outlines, that the most suitable approach to establish a sustainable traceability chain is to fix a reference system based on plasmid DNA.JRC.D.2-Reference material