The Odor Specificities of a Subset of Olfactory Receptor Neurons Are Governed by Acj6, a POU-Domain Transcription Factor

AbstractLittle is known about how the odor specificities of olfactory neurons are generated, a process essential to olfactory coding. We have found that neuronal identity relies on the abnormal chemosensory jump 6 (acj6) gene, originally identified by a defect in olfactory behavior. Physiological analysis of individual olfactory neurons shows that in acj6 mutants, a subset of neurons acquires a different odorant response profile. Certain other neurons do not respond to any tested odors in acj6. Molecular analysis of acj6 shows that it encodes a POU-domain transcription factor expressed in olfactory neurons. Our data suggest that the odor response spectrum of an olfactory neuron, and perhaps the choice of receptor genes, is determined through a process requiring the action of Acj6

Acute Pancreatitis Complicated with Choledochal Duct Rupture

Recurrent acute pancreatitis is a rare clinical entity in childhood with unknown incidence (Rosendahl et al., 2007) and often occurring in a familial context. Genetic factors such as PRSS1 mutations (cationic trypsinogen gene) can be found in some patients. However, many remain idiopathic. The natural history remains poorly documented and the most frequent complications reported are pain, exocrine pancreatic insufficiency, diabetes mellitus, and pancreatic adenocarcinoma after long-standing hereditary pancreatitis. We describe a patient with hereditary pancreatitis in whom a mild pancreatitis episode was complicated by a perforation of the ductus choledochus

Hyperdynamic Myocardial Response to Beta-Adrenergic Stimulation in Patients With Chest Pain and Normal Coronary Arteries

ObjectivesThe goal of this study was to test the hypothesis that an abnormal response to beta-adrenergic stimulation may play a role in the pathophysiology of chest pain in patients with normal coronary arteries.BackgroundThe mechanism of angina-like (AL) chest pain in patients with angiographically normal coronary arteries remains controversial.MethodsFifty-eight patients with AL pain and a normal coronary angiogram underwent dobutamine echocardiography (DE) to evaluate regional wall motion and intraventricular flow velocities (IFV). Control patients consisted of 22 matched patients free of angina and coronary artery disease. Abnormal IFV were defined as dagger-shaped Doppler spectrum ≥3 m/s.ResultsDobutamine-induced regional wall motion abnormalities did not develop in any of the patients. An IFV ≥ 3 m/s was found in 28 patients (48%) with AL pain but in only 4 (18%) control patients (p < 0.05). In the subgroup of patients with AL pain and IFV ≥3 m/s, plasma renin concentration (PRC) was higher as compared with those with IFV <3 m/s (18 ± 17 pg/ml vs. 9 ± 6 pg/ml, p < 0.05). There were no differences in plasma ADR, NADR, or angiotensin-converting enzyme levels. Fourteen patients with angina and IFV ≥3 underwent control DE and blood sampling after 6 weeks treatment with 10 mg of bisoprolol. In these patients, a decrease in IFV (from 3.4 ± 0.35 m/s to 2.46 ± 0.64 m/s, p < 0.001) and a decrease in angina score (from 5.4 ± 1.5 to 0.6 ± 1.4, p < 0.001) were observed at follow-up.ConclusionsThe present data suggest that an exaggerated myocardial response to beta-adrenergic stimulation plays a role in the mechanisms of chest pain in some patients with normal coronary arteries

A Screen for Genes Expressed in the Olfactory Organs of Drosophila melanogaster Identifies Genes Involved in Olfactory Behaviour

BACKGROUND: For insects the sense of smell and associated olfactory-driven behaviours are essential for survival. Insects detect odorants with families of olfactory receptor proteins that are very different to those of mammals, and there are likely to be other unique genes and genetic pathways involved in the function and development of the insect olfactory system. METHODOLOGY/PRINCIPAL FINDINGS: We have performed a genetic screen of a set of 505 Drosophila melanogaster gene trap insertion lines to identify novel genes expressed in the adult olfactory organs. We identified 16 lines with expression in the olfactory organs, many of which exhibited expression of the trapped genes in olfactory receptor neurons. Phenotypic analysis showed that six of the lines have decreased olfactory responses in a behavioural assay, and for one of these we showed that precise excision of the P element reverts the phenotype to wild type, confirming a role for the trapped gene in olfaction. To confirm the identity of the genes trapped in the lines we performed molecular analysis of some of the insertion sites. While for many lines the reported insertion sites were correct, we also demonstrated that for a number of lines the reported location of the element was incorrect, and in three lines there were in fact two pGT element insertions. CONCLUSIONS/SIGNIFICANCE: We identified 16 new genes expressed in the Drosophila olfactory organs, the majority in neurons, and for several of the gene trap lines demonstrated a defect in olfactory-driven behaviour. Further characterisation of these genes and their roles in olfactory system function and development will increase our understanding of how the insect olfactory system has evolved to perform the same essential function to that of mammals, but using very different molecular genetic mechanisms

Integrating Heterogeneous Odor Response Data into a Common Response Model: A DoOR to the Complete Olfactome

We have developed a new computational framework for merging odor response data sets from heterogeneous studies, creating a consensus metadatabase, the database of odor responses (DoOR). As a result, we obtained a functional atlas of all available odor responses in Drosophila melanogaster. Both the program and the data set are freely accessible and downloadable on the Internet (http://neuro.uni-konstanz.de/DoOR). The procedure can be adapted to other species, thus creating a family of “olfactomes” in the near future. Drosophila melanogaster was chosen because of all species this one is closest to having the complete olfactome characterized, with the highest number of deorphanized receptors available. The database guarantees long-term stability (by offering time-stamped, downloadable versions), up-to-date accuracy (by including new data sets as soon as they are published), and portability (for other species). We hope that this comprehensive repository of odor response profiles will be useful to the olfactory community and to computational neuroscientists alike

Definitions and methodology for the grayscale and radiofrequency intravascular ultrasound and coronary angiographic analyses

Objectives: In a prospective study of the natural history of coronary atherosclerosis using angiography and grayscale and radio

Arp 116: Interacting System or Chance Alignment?

Using high spatial resolution Hubble Space Telescope/Advanced Camera for Surveys archival imaging observations of Arp 116, centred on the elliptical galaxy NGC 4649, we explore the novel technique of pixel-by-pixel analysis of the galaxy's colour-magnitude diagramme to search for any evidence of recent enhanced star formation due to the apparent tidal interaction with its spiral companion, NGC 4647. From a detailed analysis of the system's geometry, and based on additional circumstantial evidence from extant multi-wavelength observations, we conclude that, while there may be grounds for the tidal-interaction assumption for this system, any interaction has thus far been of insufficient strength to trigger an enhanced level of recent star formation in the elliptical component, although close inspection of our colour images shows a faint excess of bluer pixels (a ~0.20 mag bluer "loop") in the elliptical galaxy on the side of the spiral companion. Given that there appears to be a moderate reservoir of available gas for ongoing star formation (although at low column density), this suggests that we are currently witnessing the onset of the tidal interaction between NGC 4647 and NGC 4649. In addition, the triggering of new star formation in NGC 4649 may be significantly impeded due to the much lower mass of the spiral component.Comment: A&A, in press; 7 pages, including one postscript figure at reduced resolutio