Linkage disequilibrium and genomic scan to detect selective loci in cattle populations adapted to different ecological conditions in Ethiopia.

Despite the wide range of observed phenotypic diversities and adaptation to different ecological conditions, little has been studied regarding the genetics of adaptation in the genome of indigenous cattle breeds of developing countries. Here, we investigated the linkage disequilibrium (LD) and identified the subset of outlier loci that are highly differentiated among cattle populations adapted to different ecological conditions in Ethiopia. Specifically, we genotyped 47 unrelated animals sampled from high- versus low-altitude environments using a Bovine 50K SNP BeadChip. Linkage disequilibrium was assessed using both D' and r(2) between adjacent SNPs. We calculated FST and heterozygosity at different significance levels as measures of genetic differentiation for each locus between high- and low-altitude populations following the hierarchical island model approach. We identified 816 loci (p < 0.01) showing selection signals and are associated with genes that might have roles in local adaptation. Some of them are associated with candidate genes that are involved in metabolism (ATP2A3, CA2, MYO18B, SIK3, INPP4A, and IREB2), hypoxia response (BDNF, TFRC, and PML) and heat stress (PRKDC, CDK1, and TFDC). Average r(2) and D' values were 0.14 ± 0.21 and 0.57 ± 0.34, respectively, for a minor allele frequency (MAF) ≥ 0.05 and were found to increase with increasing MAF value. The outlier loci identified in the studied Ethiopian cattle populations indicate the presence of genetic variation produced/shaped by adaptation to different environmental conditions and provide a basis for further validation and functional analysis using a reasonable sample size and high-density markers.

Bolus retention in hiatal hernia identified by high-resolution esophageal manometry with impedance.

BACKGROUND: Esophageal acid retention in a hiatal hernia (HH) may play a role in gastro-esophageal reflux. The aims of this study were to determine the prevalence of bolus retention (BR) in HH and to compare pressure profiles in patients with HH with BR in the hernia to those with bolus clearance (BC) through the hernia using high-resolution esophageal manometry with impedance (HREMI). METHODS: Clinical HREMI studies with HH ≥1.5 cm were analyzed for lower esophageal sphincter (LES) and crural diaphragm (CD) pressures and pressure profiles during 12 saline swallows. Impedance was analyzed for swallow retention in the HH. KEY RESULTS: Bolus retention in a HH was present in 35 of 53 (66%) patients with a HH. Patients with BR had overall lower pressure profiles including a lower basal LES pressure (14.8 ± 10.6 vs 28.9 ± 16.8 mmHg; p = 0.0001), LES-CD gradient (6.8 ± 17.9 vs 20.6 ± 12.2 mmHg; p = 0.002), residual LES pressure (2.5 ± 4.6 vs 6.1 ± 12.2 mmHg; p = 0.017), amplitude of distal esophageal contractions (83.2 ± 38.8 vs 111.2 ± 42.8 mmHg; p = 0.020), and distal contractile integral (1487 ± 1016 vs 2608 ± 1221 mmHg-cm-sec; p = 0.001) compared to the BC group. Patients with BR were more likely to have a larger sized HH compared to the BC group (3.1 ± 1.6 vs 2.1 ± 0.6 cm; p = 0.016); similar pressure changes were found when the groups were divided up by HH sizes. CONCLUSIONS & INFERENCES: Bolus retention was seen in 66% of patients with HH. Bolus retention in the HH was associated with larger HH size, lower LES pressure, and lower esophageal contractile pressures compared to those with BC.

The study of beta-lactoglobulin adsorption on polyethersulfone thin film surface using QCM-D and AFM.

The adsorption process of beta-lactoglobulin on the polyethersulfone-coated surface has been investigated using a quartz crystal microbalance with dissipation monitoring (QCM-D), which allowed simultaneous measurements of frequency and energy dissipation changes caused by the formation of a beta-lactoglobulin layer during the protein adsorption process. The results showed that the protein adsorption on the spin-coated polyethersulfone surface consisted of reversible and irreversible adsorption processes, and the irreversible adsorption was the principal factor to cause the permanent protein adsorption onto the polymer surface. The amount of irreversible adsorption of beta-lactoglobulin increased significantly, from 380.5 +/- 23.2 to 745.5 +/- 29.7 ng/cm2, when the concentration of beta-lactoglobulin solution varied from 0.1% to 2.0% (w/v). The pH also played an important role in the protein adsorption. When the pH of the solution varied from 7.0 to 3.0, the amount of irreversible adsorption of beta-lactoglobulin increased from 427.1 +/- 80.7 to 741.2 +/- 135.1 ng/cm2.