Gut microbiota composition in himalayan and andean populations and its relationship with diet, lifestyle and adaptation to the high-altitude environment

Human populations living at high altitude evolved a number of biological adjustments to cope with a challenging environment characterised especially by reduced oxygen availability and limited nutritional resources. This condition may also affect their gut microbiota composition. Here, we explored the impact of exposure to such selective pressures on human gut microbiota by considering different ethnic groups living at variable degrees of altitude: the high-altitude Sherpa and low-altitude Tamang populations from Nepal, the high-altitude Aymara population from Bolivia, as well as a low-altitude cohort of European ancestry, used as control. We thus observed microbial profiles common to the Sherpa and Aymara, but absent in the low-altitude cohorts, which may contribute to the achievement of adaptation to high-altitude lifestyle and nutritional conditions. The collected evidences suggest that microbial signatures associated to these rural populations may enhance metabolic functions able to supply essential compounds useful for the host to cope with high altitude-related physiological changes and energy demand. Therefore, these results add another valuable piece of the puzzle to the understanding of the beneficial effects of symbiosis between microbes and their human host even from an evolutionary perspective

Evolutionary and phenotypic characterization of two spike mutations in European lineage 20E of SARS-CoV-2.

We have detected two mutations in the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at amino acid positions 1163 and 1167 that appeared independently in multiple transmission clusters and different genetic backgrounds. Furthermore, both mutations appeared together in a cluster of 1,627 sequences belonging to clade 20E. This cluster is characterized by 12 additional single nucleotide polymorphisms but no deletions. The available structural information on the S protein in the pre- and postfusion conformations predicts that both mutations confer rigidity, which could potentially decrease viral fitness. Accordingly, we observed reduced infectivity of this spike genotype relative to the ancestral 20E sequence in vitro, and the levels of viral RNA in nasopharyngeal swabs were not significantly higher. Furthermore, the mutations did not impact thermal stability or antibody neutrali- zation by sera from vaccinated individuals but moderately reduce neutralization by convalescent-phase sera from the early stages of the pandemic. Despite multi- ple successful appearances of the two spike mutations during the first year of SARS-CoV-2 evolution, the genotype with both mutations was displaced upon the expansion of the 20I (Alpha) variant. The midterm fate of the genotype investi- gated was consistent with the lack of advantage observed in the clinical and ex- perimental data

High-Throughput Sequencing of RNA Silencing-Associated Small RNAs in Olive (Olea europaea L.)

Small RNAs (sRNAs) of 20 to 25 nucleotides (nt) in length maintain genome integrity and control gene expression in a multitude of developmental and physiological processes. Despite RNA silencing has been primarily studied in model plants, the advent of high-throughput sequencing technologies has enabled profiling of the sRNA component of more than 40 plant species. Here, we used deep sequencing and molecular methods to report the first inventory of sRNAs in olive (Olea europaea L.). sRNA libraries prepared from juvenile and adult shoots revealed that the 24-nt class dominates the sRNA transcriptome and atypically accumulates to levels never seen in other plant species, suggesting an active role of heterochromatin silencing in the maintenance and integrity of its large genome. A total of 18 known miRNA families were identified in the libraries. Also, 5 other sRNAs derived from potential hairpin-like precursors remain as plausible miRNA candidates. RNA blots confirmed miRNA expression and suggested tissue- and/or developmental-specific expression patterns. Target mRNAs of conserved miRNAs were computationally predicted among the olive cDNA collection and experimentally validated through endonucleolytic cleavage assays. Finally, we use expression data to uncover genetic components of the miR156, miR172 and miR390/TAS3-derived trans-acting small interfering RNA (tasiRNA) regulatory nodes, suggesting that these interactive networks controlling developmental transitions are fully operational in olive

Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020

We show the distribution of SARS-CoV-2 genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three available genomic nomenclature systems for SARS-CoV-2 to all sequence data from the WHO European Region available during the COVID-19 pandemic until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation. We provide a comparison of the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2.Peer reviewe

Ruminal degradation of the dry matter of the cuajilote fruit (Parmentiera edulis) [Degradaci�n ruminal de la materia seca del fruto cuajilote (Parmentiera edulis)]

This study had the aim to estimate the ruminal degradability and kinetic degradative of the dry matter (MS) of the cuajilote fruit (Parmentiera edulis DC) in three states of maturity collected during the dry season in a humid warm climate region of the coast at Chiapas state, Mexico, to analyze its forage potential. The technique of nylon bag was applied with heifers permanently fissured of rumen (being used like experimental units) that grazed star of Africa grass and a supplementation with 400 g/d of concentrate (grain of ground sorghum, paste of soya and minerals). They were incubated in rumen, 5 g of ground of cuajilote sample (chilillos, green, and mature) in nylon bags (large: 10 x 5 cm and pore: 52 ?) in periods of 0, 4, 8, 12, 24, 36, 48, and 72 h. The treatments (maturity states) were distributed in a completely random design with four repetitions by treatment. The disappearance of the MS (DISMS, %) of the chilillos was twice greater (P<0.001) than the green, although smaller than the DISMS of the mature fruit. The type of MS fluctuated (P<0,001) depending on the maturity state, showing that degradable MS and soluble MS were more elevated in the mature fruit, followed by the chilillos and the greens (14,6 and 7.3 vs. 1,5%, as well as 29,3, 25,2 vs. 15,7%, respectively). On the other side, the degradable MS of the mature fruit begins to degrade more rapidly (0.0, 1.6, and 1.8 h for mature, chilillos, and greens, respectively) and a faster rate than the chilillos or greens (0.04 vs 0.03). The potential digestibility of the MS (%) was higher (P<0.05) in mature fruit (43.9) than the chilillos (32.0) and the greens (17.2). The same tendency appeared for the effective degradability. It is concluded that the MS of the mature fruit showed more availability of ruminal degradation than the chilillos and the greens, but the dry matter of this fruit showed a low ruminal availability indicating that it is not a material that can replace tropical forages

Ruminal degradation of the dry matter of the cuajilote fruit (Parmentiera edulis) [Degradación ruminal de la materia seca del fruto cuajilote (Parmentiera edulis)]

This study had the aim to estimate the ruminal degradability and kinetic degradative of the dry matter (MS) of the cuajilote fruit (Parmentiera edulis DC) in three states of maturity collected during the dry season in a humid warm climate region of the coast at Chiapas state, Mexico, to analyze its forage potential. The technique of nylon bag was applied with heifers permanently fissured of rumen (being used like experimental units) that grazed star of Africa grass and a supplementation with 400 g/d of concentrate (grain of ground sorghum, paste of soya and minerals). They were incubated in rumen, 5 g of ground of cuajilote sample (chilillos, green, and mature) in nylon bags (large: 10 x 5 cm and pore: 52 μ) in periods of 0, 4, 8, 12, 24, 36, 48, and 72 h. The treatments (maturity states) were distributed in a completely random design with four repetitions by treatment. The disappearance of the MS (DISMS, %) of the chilillos was twice greater (P<0.001) than the green, although smaller than the DISMS of the mature fruit. The type of MS fluctuated (P<0,001) depending on the maturity state, showing that degradable MS and soluble MS were more elevated in the mature fruit, followed by the chilillos and the greens (14,6 and 7.3 vs. 1,5%, as well as 29,3, 25,2 vs. 15,7%, respectively). On the other side, the degradable MS of the mature fruit begins to degrade more rapidly (0.0, 1.6, and 1.8 h for mature, chilillos, and greens, respectively) and a faster rate than the chilillos or greens (0.04 vs 0.03). The potential digestibility of the MS (%) was higher (P<0.05) in mature fruit (43.9) than the chilillos (32.0) and the greens (17.2). The same tendency appeared for the effective degradability. It is concluded that the MS of the mature fruit showed more availability of ruminal degradation than the chilillos and the greens, but the dry matter of this fruit showed a low ruminal availability indicating that it is not a material that can replace tropical forages

The three major axes of terrestrial ecosystem function

The leaf economics spectrum(1,2) and the global spectrum of plant forms and functions(3) revealed fundamental axes of variation in plant traits, which represent different ecological strategies that are shaped by the evolutionary development of plant species(2). Ecosystem functions depend on environmental conditions and the traits of species that comprise the ecological communities(4). However, the axes of variation of ecosystem functions are largely unknown, which limits our understanding of how ecosystems respond as a whole to anthropogenic drivers, climate and environmental variability(4,5). Here we derive a set of ecosystem functions(6) from a dataset of surface gas exchange measurements across major terrestrial biomes. We find that most of the variability within ecosystem functions (71.8%) is captured by three key axes. The first axis reflects maximum ecosystem productivity and is mostly explained by vegetation structure. The second axis reflects ecosystem water-use strategies and is jointly explained by variation in vegetation height and climate. The third axis, which represents ecosystem carbon-use efficiency, features a gradient related to aridity, and is explained primarily by variation in vegetation structure. We show that two state-of-the-art land surface models reproduce the first and most important axis of ecosystem functions. However, the models tend to simulate more strongly correlated functions than those observed, which limits their ability to accurately predict the full range of responses to environmental changes in carbon, water and energy cycling in terrestrial ecosystems(7,8).Peer reviewe

The Jaen Statement 2004: Consensus document of the International Conference on the healthy effects of virgin olive oil

Aging represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, Parkinson, Alzheimer, vascular dementia, cognitive decline, diabetes and cancer. Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of cardiovascular disease. The Mediterranean diet, rich in virgin olive oil, improves the major risk factors for cardiovascular disease, such as the lipoprotein profile, blood pressure, glucose metabolism antiantithrombotic profile. Endothelial function, inflammation and oxidative stress are also positively modulated. Some of these effects are attributed to minor components of virgin olive oil. Therefore, the definition of the Mediterranean diet should include virgin olive oil. Different observational studies conducted in humans have shown that the intake of monounsaturated fat may be protective against age-related cognitive decline and Alzheimer's disease. Microconstituents from virgin olive oil are bioavailable in humans and have shown antioxidant properties and capacity to improve endothelial function. Furthermore, they are also able to modify the haemostasis, showing antithrombotic properties. In countries in which the populations fulfilled a typical Mediterranean diet, such as Spain, Greece, and Italy, where virgin olive oil is the principal source of fat, cancer incidence rates are lower than in Northern European countries. The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life. The more recent studies consistently support that the Mediterranean diet, based in virgin olive oil, is compatible with a healthier aging and increased longevity. However, despite the significant advances of the recent years, the final proof about the specific mechanisms and contributing role of the different components of virgin olive oil to its beneficial effects requires further investigations