Mating-based regulation and ligand binding of an odorant-binding protein support the inverse sexual communication of the greater wax moth, Galleria mellonella (Lepidoptera: Pyralidae).

In moths, sex pheromones play a key role in mate finding. These chemicals are transported in the antennae by odorant-binding proteins (OBPs). Commonly, males encounter conspecific females; therefore, several OBPs are male-biased. Less is known, however, about how the olfactory system of moths has evolved toward inverse sexual communication, ie where females seek males. Therefore, the objective of this study was to identify the profile of OBPs and their expression patterns in the bee hive pest, Galleria mellonella, a moth that uses inverse sexual communication. Here, OBP-related transcripts were identified by an RNA Sequencing (RNA-Seq) approach and analysed through both Reverse Transcription Polymerase Chain Reaction (RT-PCR) in different tissues and quantitative real-time PCR for two states, virgin and postmating. Our results indicate that G. mellonella has 20 OBPs distributed amongst different tissues. Interestingly, 17 of the 20 OBPs were significantly down-regulated after mating in females, whereas only OBP7 was up-regulated. By contrast, 18 OBP transcripts were up-regulated in males after mating. Additionally, binding assays and structural simulations showed general odorant-binding protein 2 (GOBP2) was able to bind sex pheromone components and analogues. These findings suggest a possible role of OBPs, especially GOBPs, in the inverse sexual communication of G. mellonella, with gene expression regulated as a response to mating.

Fault diagnosis viewed as a left invertibility problem.

This work deals with the fault diagnosis problem, some new properties are found using the left invertibility condition through the concept of differential output rank. Two schemes of nonlinear observers are used to estimate the fault signals for comparison purposes, one of these is a proportional reduced order observer and the other is a sliding mode observer. The methodology is tested in a real time implementation of a three-tank system.

Prevalence of Helicobacter pylori in neonates and young infants undergoing ERCP for diagnosis of neonatal cholestasis.

This study was carried out to determine the prevalence of Helicobacter pylori infection in 20 neonates and young infants from lower socioeconomic background undergoing endoscopic retrograde cholangiopancreatography (ERCP) examination for diagnosis of neonatal cholestasis. One young asymptomatic infant (5%) who was breast-feeding with complementary formula had H. pylori infection. Endoscopy showed a normal appearing mucosa and histology demonstrated mild superficial acute gastritis. A follow-up gastroscopy performed 14 months after the initial study showed normal histology without evidence of H. pylori, suggesting that the infection was transient. Nineteen (95%) of the 20 mothers had H. pylori infection, including the mother with the infant positive for H. pylori. All mothers had gastritis on biopsy specimens. Despite the high prevalence of H. pylori in the mothers, infection in neonates and young infants was uncommon.