Association of platelet count and serological markers of dengue infection- importance of NS1 antigen

Introduction: Dengue is an acute viral infection with potential fatal complications. Specific antibody detection has been the mainstay of diagnosis which is prone for both false positive and false negative reactions. The newer parameter NS1 appears to be highly specific and reliable for diagnosis of dengue infection from the first day of fever. Platelet count is the only accessory test for diagnosis of dengue infection in the peripheral laboratories. Therefore, we tried to evaluate the association of platelet counts against NS1 and IgM/IgG in dengue infections. Materials and Methods: Serum samples from clinically suspected dengue cases were tested for NS1, IgM and IgG by immunochromatography-based test. Platelet counts were obtained for all positive cases and 150 dengue seronegative cases of fever that served as controls. Test results of dengue-specific parameters were compared against platelet counts. The proportions obtained were compared by Standard error of the difference between the proportions (SEP test). Results: Of 2104 samples tested, 320 were positive for one or more dengue parameters. Of the 320, 95 were positive for NS1 only, 161 showed IgM only while 9 showed IgG only. More than one marker was detected in the remaining 55 samples. Thrombocytopenia was more consistently associated whenever NS1 was detected compared to antibody detection (P value <0.001). Conclusions: Inclusion of NS1 in the diagnosis of dengue increases the detection rate significantly. In cases of fever, thrombocytopenia is more consistently found in dengue positive rather than dengue negative subjects. It correlates well when NS1 and IgM are detected simultaneously

Comparative transcriptomics enables the identification of functional orthologous genes involved in early leaf growth.

Leaf growth is a complex trait for which many similarities exist in different plant species, suggesting functional conservation of the underlying pathways. However, a global view of orthologous genes involved in leaf growth showing conserved expression in dicots and monocots is currently missing. Here we present a genome-wide comparative transcriptomics analysis between Arabidopsis and maize, identifying conserved biological processes and gene functions active during leaf growth. Despite the orthology complexity between these distantly related plants, 926 orthologous gene groups including 2,829 Arabidopsis and 2,974 maize genes with similar expression during leaf growth were found, indicating conservation of the underlying molecular networks. We found 65% of these genes involved in one-to-one orthology, whereas only 28.7% of the groups with divergent expression had one-to-one orthology. Within the pool of genes with conserved expression, 19 transcription factor families were identified, demonstrating expression conservation of regulators active during leaf growth. Additionally, 25 Arabidopsis and 25 maize putative targets of the TCP TFs with conserved expression were determined based on the presence of enriched transcription factor binding sites. Based on large-scale phenotypic data, we observed that genes with conserved expression have a higher probability to be involved in leaf growth and that leaf-related phenotypes are more frequently present for genes having orthologs between dicots and monocots than clade-specific genes. This study shows the power of integrating transcriptomics with orthology data to identify or select candidates for functional studies during leaf development in flowering plants