Ecological factors affecting wetland occupancy by breeding Anatidae in the southwestern mediterranean

Conservation of Anatidae in North Africa is hindered by lack of information concerning population size, population trends, and species-habitat relationships. In this work, we used a 2-year survey data in 25 wetlands distributed throughout Morocco to model duck spatial distribution and to assess the relevance of a set of environmental and anthropogenic factors in predicting site occupancy, by means of Generalized Linear Mixed Models (GLMM). Mallards and Ferruginous ducks were the most commonly detected species, whereas White-Headed Ducks and Common Pochards were the least detected ones. An inter-annual variation in site occupancy was recorded for Ruddy Shelducks, Red-Crested Pochards and White-Headed Ducks. Geographical location (measured mainly as distance to the coastline and altitude) was the major predictor of the occurrence probability of Ruddy Shelducks, Marbled Teals and Red-Crested Pochards, while human presence and habitat features were the most relevant factors in shaping Mallard’s distribution. However, none of the considered environmental and anthropogenic factors explained the distribution patterns of the Ferruginous Duck, Common Pochard and Gadwall. The results of this study clearly show that there are still gaps in our knowledge on factors driving wetland occupancy by breeding Anatidae in Morocco. The pursuit of the investigations, while considering other explanatory factors such as water quality (limnological data), diet, predation, and conservation status, is of great importance to more profoundly understand the dynamics of Moroccan duck populations.     

The Drosophila melanogaster Phospholipid Flippase dATP8B Is Required for Odorant Receptor Function

The olfactory systems of insects are fundamental to all aspects of their behaviour, and insect olfactory receptor neurons (ORNs) exhibit exquisite specificity and sensitivity to a wide range of environmental cues. In Drosophila melanogaster, ORN responses are determined by three different receptor families, the odorant (Or), ionotropic-like (IR) and gustatory (Gr) receptors. However, the precise mechanisms of signalling by these different receptor families are not fully understood. Here we report the unexpected finding that the type 4 P-type ATPase phospholipid transporter dATP8B, the homologue of a protein associated with intrahepatic cholestasis and hearing loss in humans, is crucial for Drosophila olfactory responses. Mutations in dATP8B severely attenuate sensitivity of odorant detection specifically in Or-expressing ORNs, but do not affect responses mediated by IR or Gr receptors. Accordingly, we find dATP8B to be expressed in ORNs and localised to the dendritic membrane of the olfactory neurons where signal transduction occurs. Localisation of Or proteins to the dendrites is unaffected in dATP8B mutants, as is dendrite morphology, suggesting instead that dATP8B is critical for Or signalling. As dATP8B is a member of the phospholipid flippase family of ATPases, which function to determine asymmetry in phospholipid composition between the outer and inner leaflets of plasma membranes, our findings suggest a requirement for phospholipid asymmetry in the signalling of a specific family of chemoreceptor proteins.     

Identification of candidate genes for nicotine withdrawal in C57BL/6J × DBA/2J recombinant inbred mice

Nicotine is the reinforcing ingredient in tobacco. Following chronic exposure, sudden cessation of nicotine use produces negative symptoms of withdrawal that contribute to dependence. The molecular mechanisms underlying nicotine withdrawal behaviors, however, are poorly understood. Using recombinant inbred mice, chronic nicotine was delivered by minipump and withdrawal induced using mecamylamine. Somatic signs of withdrawal, and anxiety-like behavior using elevated plus maze, were then assessed. Interval mapping was used to identify associations between genetic variation and withdrawal behaviors, and with basal gene expression. Differential gene expression following nicotine exposure and withdrawal was also assessed in progenitor mice using microarrays. Quantitative trait loci mapping identified chromosome intervals with significant genetic associations to somatic signs of withdrawal or withdrawal-induced anxiety-like behavior. Using bioinformatics, and association with basal gene expression in nucleus accumbens, we implicated Rb1, Bnip3l, Pnma2, Itm2b, and Kif13b as candidate genes for somatic signs of withdrawal, and Galr1, which showed trans-regulation from a region of chromosome 14 that was associated with somatic signs of withdrawal. Candidate genes within the chromosome 9 region associated with anxiety-like withdrawal behavior included Dixdc1, Ncam1, and Sorl1. Bioinformatics identified six genes that were also significantly associated with nicotine or alcohol traits in recent human genome-wide association studies. Withdrawal-associated somatic signs and anxiety-like behavior had strong non-overlapping genetic associations, respectively, with regions of chromosome 14 and chromosome 9. Genetic, behavioral and gene expression correlations, and bioinformatics analysis identified several candidate genes that may represent novel molecular targets for modulating nicotine withdrawal symptoms.     

Effect of Omeprazole Therapy on the Survival of Helicobacter pylori, Urease Activity, and Antral Gastric Histology in Patients with Duodenal Ulcer

Background. Helicobacter pylori is associated with chronic active gastritis and peptic ulceration (PU). Omeprazole is a proton pump inhibitor that is effective in healing PU and reducing gastritis. Previously it has been found that omeprazole has some bacteriostatic activity against H. pylori both in vitro and in vivo and in inhibiting urease activity in vitro. Our aim was to evaluate the effect of omeprazole on H. pylori colonization of the gastric mucosa, urease activity in vivo, and the presence of associated gastritis in patients with duodenal ulcer (DU).
Materials and Methods. We studied 12 patients (7 men and 5 women, ages 22–68 yr) with Du larger than 5 mm in diameter with a positive CLOtest (Delta West Ltd., Australia). Omeprazole, 20 mg bid, was given for 8 weeks to each patient, patients were endoscoped at the end of this period to check for healing of DU, and repeat biopsies were obtained from the gastric antrum for histologyical analysis, CLOtest, and culture.
Results. DU healed completely in all patients. Likewise in all patients there was significant reduction in the urease activity, from 22.1=4.17 to 1.58 ± 0.92 units/ml ( p <.001; 95% confidence interval of the difference between means, 32.7–14.1), and reduced H. pylori density, from 1,403.46 ± 128.23 to 422.5 ± 172.39 colony-forming units (CFU) per milligram of tissue biopsy ( p < .001; 95% confidence interval of the difference between means, 1,486.1–590.5). The numbers of H. pylori were reduced on the gastric mucosa after omeprazole therapy and disappeared in six patients, a result that correlated with a negative CLOtest reading after 24 hours.
Conclusion. Omeprazole, 20 mg bid, is capable of reducing H. pylori numbers and urease activity in vivo. There was no significant reduction in the severity of antral gastritis in DU patients studied.     

A roadmap to Durable BCTV Resistance Using Long-Read Genome Assembly of Genetic Stock KDH13

Plant Molecular Biology Reporter - Beet Curly Top (BCT) is a viral disease which negatively impacts crop productivity for sugar beet growers and the sugar beet industry in the western USA and dry...     

Systems genetic analysis of binge-like eating in a C57BL/6J x DBA/2J-F2 cross

Binge eating is a heritable trait associated with eating disorders and refers to the rapid consumption of a large quantity of energy-dense food that is, associated with loss of control and negative affect. Binge eating disorder is the most common eating disorder in the United States; however, the genetic basis is unknown. We previously identified robust mouse inbred strain differences between C57BL/6J and DBA/2J in binge-like eating of sweetened palatable food in an intermittent access, conditioned place preference paradigm. To map the genetic basis of changes in body weight and binge-like eating (BLE) and to identify candidate genes, we conducted quantitative trait locus (QTL) analysis in 128 C57BL/6J x DBA/2J-F2 mice combined with PheQTL and trait covariance analysis in GeneNetwork2 using legacy BXD-RI trait datasets. We identified a QTL on Chromosome 18 influencing changes in body weight across days in females (log of the odds [LOD] = 6.3; 1.5-LOD: 3–12 cM) that contains the candidate gene Zeb1. We also identified a sex-combined QTL influencing initial palatable food intake on Chromosome 5 (LOD = 5.8; 1.5-LOD: 21–28 cM) that contains the candidate gene Lcorl and a second QTL influencing escalated palatable food intake on Chromosome 6 in males (LOD = 5.4; 1.5-LOD: 50–59 cM) that contains the candidate genes Adipor2 and Plxnd1. Finally, we identified a suggestive QTL in females for slope of BLE on distal Chromosome 18 (LOD = 4.1; p = 0.055; 1.5-LOD: 23–35 cM). Future studies will use BXD-RI strains to fine map loci and support candidate gene nomination for gene editing.