Project description:Shorebirds (part of the order Charadriiformes) have a global distribution and exhibit remarkable variation in ecological and behavioural traits that are pertinent to many core questions in the fields of evolutionary ecology and conservation biology. Shorebirds are also relatively convenient to study in the wild as they are ground nesting and often occupy open habitats that are tractable to monitor. Here we present a database documenting the reproductive ecology of 1,647 individually marked snowy plovers (Charadrius nivosus) monitored between 2006 and 2016 at Bahía de Ceuta (23°54N, 106°57W) - an important breeding site in north-western Mexico. The database encompasses various morphological, behavioural, and fitness-related traits of males and females along with spatial and temporal population dynamics. This open resource will serve as an important data repository for addressing overarching questions in avian ecology and wetland conservation during an era of big data and global collaborative science.
Project description:Ulcerative colitis (UC) is an inflammation of the colon that can progress to colorectal cancer if left untreated. No medication completely cures UC and natural products are sources of alternative approaches. This study aimed to determine the anti-inflammatory potential of Phyllanthus nivosus leaf extract and fractions in a rat model of ulcerative colitis and to identify the active ingredients. UC was induced in rats by intra-rectal infusion of 1ml of 4% acetic acid (AA) in normal saline. AA exposed groups of rats were treated with 100 mg/kg bodyweight of methanol extract, hexane, ethyl-acetate and butanol fractions orally for four days. Another group received the standard drug - Dexamethasone and control rats were given distilled water only. Some biochemical changes were evaluated and the active ingredients were identified using Gas Chromatography-Mass Spectrometry (GC-MS) followed by molecular docking against interleukin-1-beta converting enzyme (Caspase-1), beta-2 adrenergic receptor (ADRB2), cyclooxygenase-2 (COX-2) and tumour necrosis factor-alpha (TNF-α). Exposure of rat colon to acetic acid significantly altered (p < 0.05) serum levels of tumour necrosis factor-alpha (TNF-α), interleukin - 6 (IL-6), nitric oxide (NO), lipid peroxidation product (malondialdehyde or MDA), reduced glutathione (GSH); and activities of superoxide dismutase (SOD) and catalase (CAT). These alterations were however restored in the rats treated with P. nivosus leaf with the ethyl-acetate fraction displaying the highest ameliorative activity. GC-MS analysis of the ethyl acetate fraction revealed the presence of 40 compounds which when subjected to molecular docking demonstrated varying degrees of binding affinities for the protein targets. Ethyl iso-allocholate demonstrated the highest binding affinity for caspase-1, cholest-22-ene-21-ol, 3,5-dehydro-6- methoxy-, pivalate for ADRB2 and TNF-α; and alpha-cadinol for COX-2. The anti-inflammatory potential of Phyllanthus nivosus leaf as a natural remedy and as a source of new drugs against ulcerative colitis is validated.
Project description:BackgroundUnderstanding the structure and variability of adaptive loci such as the major histocompatibility complex (MHC) genes is a primary research goal for evolutionary and conservation genetics. Typically, classical MHC genes show high polymorphism and are under strong balancing selection, as their products trigger the adaptive immune response in vertebrates. Here, we assess the allelic diversity and patterns of selection for MHC class I and class II loci in a threatened shorebird with highly flexible mating and parental care behaviour, the Snowy Plover (Charadrius nivosus) across its broad geographic range.ResultsWe determined the allelic and nucleotide diversity for MHC class I and class II genes using samples of 250 individuals from eight breeding population of Snowy Plovers. We found 40 alleles at MHC class I and six alleles at MHC class II, with individuals carrying two to seven different alleles (mean 3.70) at MHC class I and up to two alleles (mean 1.45) at MHC class II. Diversity was higher in the peptide-binding region, which suggests balancing selection. The MHC class I locus showed stronger signatures of both positive and negative selection than the MHC class II locus. Most alleles were present in more than one population. If present, private alleles generally occurred at very low frequencies in each population, except for the private alleles of MHC class I in one island population (Puerto Rico, lineage tenuirostris).ConclusionSnowy Plovers exhibited an intermediate level of diversity at the MHC, similar to that reported in other Charadriiformes. The differences found in the patterns of selection between the class I and II loci are consistent with the hypothesis that different mechanisms shape the sequence evolution of MHC class I and class II genes. The rarity of private alleles across populations is consistent with high natal and breeding dispersal and the low genetic structure previously observed at neutral genetic markers in this species.