Time to First-Line ART Failure and Time to Second-Line ART Switch in the IeDEA Pediatric Cohort

BACKGROUND: Globally, 49% of the estimated 1.8 million children living with HIV are accessing antiretroviral therapy (ART). There are limited data concerning long-term durability of first-line ART regimens and time to transition to second-line. METHODS: Children initiating their first ART regimen between 2 and 14 years of age and enrolled in one of 208 sites in 30 Asia-Pacific and African countries participating in the Pediatric International Epidemiology Databases to Evaluate AIDS consortium were included in this analysis. Outcomes of interest were: first-line ART failure (clinical, immunologic, or virologic), change to second-line, and attrition (death or loss to program ). Cumulative incidence was computed for first-line failure and second-line initiation, with attrition as a competing event. RESULTS: In 27,031 children, median age at ART initiation was 6.7 years. Median baseline CD4% for children ≤5 years of age was 13.2% and CD4 count for those >5 years was 258 cells per microliter. Almost all (94.4%) initiated a nonnucleoside reverse transcriptase inhibitor; 5.3% a protease inhibitor, and 0.3% a triple nucleoside reverse transcriptase inhibitor-based regimen. At 1 year, 7.7% had failed and 14.4% had experienced attrition; by 5 years, the cumulative incidence was 25.9% and 29.4%, respectively. At 1 year after ART failure, 13.7% had transitioned to second-line and 11.2% had experienced attrition; by 5 years, the cumulative incidence was 31.6% and 25.9%, respectively. CONCLUSIONS: High rates of first-line failure and attrition were identified in children within 5 years after ART initiation. Of children meeting failure criteria, only one-third were transitioned to second-line ART within 5 years

BioCatalogue: a universal catalogue of web services for the life sciences

The use of Web Services to enable programmatic access to on-line bioinformatics is becoming increasingly important in the Life Sciences. However, their number, distribution and the variable quality of their documentation can make their discovery and subsequent use difficult. A Web Services registry with information on available services will help to bring together service providers and their users. The BioCatalogue (http://www.biocatalogue.org/) provides a common interface for registering, browsing and annotating Web Services to the Life Science community. Services in the BioCatalogue can be described and searched in multiple ways based upon their technical types, bioinformatics categories, user tags, service providers or data inputs and outputs. They are also subject to constant monitoring, allowing the identification of service problems and changes and the filtering-out of unavailable or unreliable resources. The system is accessible via a human-readable ‘Web 2.0’-style interface and a programmatic Web Service interface. The BioCatalogue follows a community approach in which all services can be registered, browsed and incrementally documented with annotations by any member of the scientific community

Statistical study of the night-time F-layer dynamics at the magnetic equator in West Africa during the solar minimum period 1995–1997

In this paper, we report on the night-time equatorial F-layer height behaviour at Korhogo (9.2° N, 5° W; 2.4° S dip lat), Ivory Coast, in the West African sector during the solar minimum period 1995–1997. The data were collected from quarter-hourly ionograms of an Ionospheric Prediction Service (IPS) 42-type vertical sounder. The main focus of this work was to study the seasonal changes in the F-layer height and to clarify the equinox transition process recently evidenced at Korhogo during 1995, the year of declining solar flux activity. The F-layer height was found to vary strongly with time, with up to three main phases. The night-to-night variability of these morphological phases was then analysed. The early post-sunset slow rise, commonly associated with rapid chemical recombination processes in the bottom part of the F layer, remained featureless and was observed regardless of the date. By contrast, the following event, either presented like the post-sunset height peak associated with the evening <b><i>E</i></b> × <b><i>B</b></i> drift, or was delayed to the midnight sector, thus involving another mechanism. The statistical analysis of the occurrence of these events throughout the solar minimum period 1995–1997 revealed two main F-layer height patterns, each characteristic of a specific season. The one with the post-sunset height peak was associated with the northern winter period, whereas the other, with the midnight height peak, characterized the northern summer period. The transition process from one pattern to the other took place during the equinox periods and was found to last only a few weeks. We discuss these results in the light of earlier works