Respiratory virus detection: beyond influenza and RSV into emerging infectious diseases.

In the era of global travel, clinicians can no longer consider just influenza and Respiratory Synctial Virus (RSV) and ignore other causes of presumptive viral respiratory tract infections. Since the recognition of Severe Acute Respiratory Syndrome (SARS) coronavirus in 2003, novel viruses seem to emerge more frequently. Novel influenza strains, the novel coronavirus (MERS-CoV) identified last year in the Middle East, other novel viruses, and increasing numbers of immunocompromised patients that can be felled by acute respiratory infections all demand a need for rapid recognition of the etiology of viral respiratory illnesses. This article will review viral respiratory PCR tests currently available or in development and how they can be used to improve patient care both within the hospital setting and in the outpatient setting.

Comparative physical mapping links conservation of microsynteny to chromosome structure and recombination in grasses.

Nearly finished sequences for model organisms provide a foundation from which to explore genomic diversity among other taxonomic groups. We explore genome-wide microsynteny patterns between the rice sequence and two sorghum physical maps that integrate genetic markers, bacterial artificial chromosome (BAC) fingerprints, and BAC hybridization data. The sorghum maps largely tile a genomic component containing 41% of BACs but 80% of single-copy genes that shows conserved microsynteny with rice and partially tile a nonsyntenic component containing 46% of BACs but only 13% of single-copy genes. The remaining BACs are centromeric (4%) or unassigned (8%). The two genomic components correspond to cytologically discernible "euchromatin" and "heterochromatin." Gene and repetitive DNA distributions support this classification. Greater microcolinearity in recombinogenic (euchromatic) than nonrecombinogenic (heterochromatic) regions is consistent with the hypothesis that genomic rearrangements are usually deleterious, thus more likely to persist in nonrecombinogenic regions by virtue of Muller's ratchet. Interchromosomal centromeric rearrangements may have fostered diploidization of a polyploid cereal progenitor. Model plant sequences better guide studies of related genomes in recombinogenic than nonrecombinogenic regions. Bridging of 35 physical gaps in the rice sequence by sorghum BAC contigs illustrates reciprocal benefits of comparative approaches that extend at least across the cereals and perhaps beyond.