Plants of the ‘Libellus de Medicinalibus Indorum Herbis’ from Mexico, 1552. Zephyranthes fosteri (Amaryllidaceae) Alkaloids

The Libellus de Medicinalibus Indorum Herbis (Booklet of Indian Medicinal Plants) is the first book of medicinal plants written in the American continent. It was first published in 1939 as ‘An Aztec Herbal’. One of the depicted plants is Huetzcanixochitl (laughing flower) interpreted as Zephyranthes fosteri (Amaryllidaceae). No chemical or pharmacological studies are reported for this species; so, we decide to investigate it. The GC/MS of the bulbs and aerial parts extracts indicated that they contain Amaryllidaceae alkaloids, among them: lycorine, 3-O-acetylpowelline, and norlycoramine. An unknown major alkaloid was isolated and identified by ¹H, ¹³C-NMR and MS, as 3′-demethoxy-6-epimesembranol ( 1 ). The methanolic extract, the alkaloid fraction, and compound 1 inhibited acetylcholinesterase in vitro. Mesembrine alkaloids are found in Sceletium species (Aizoaceae). Several are known as serotonin recapture inhibitors and have been proposed as potential antidepressant drugs. The presence of 1 suggests that Z. fosteri was probably used in pre-Columbian times in Mexico as a ‘stimulant and euphoriant’, alike Sceletium tortuosum by several ethnic groups in South Africa.     

Sprout recruitment and self-thinning of Erica multiflora after clipping

Regrowth after clipping and the effect of local competition were studied in a natural population of Erica multiflora in a Mediterranean shrubland, by removing neighbours at 1 and 2 m around the target plants during four growing seasons. Removal of surrounding natural vegetation increased the number, the density (number of sprouts per stump area) and the biomass of the sprouts growing from clipped plants. Target plants ònly interacted with their near neighbours. Target plants had a negative relative increment in the number of sprouts per stump during the 18 months immediately following treatment, but a positive increment thereafter, which suggests that there was a constant or episodic recruitment of sprouts within the stump after clipping. Competition treatment had a non-significant effect on the negative increment of sprouts per stump. The self-thinning trajectory was different for the different competition treatments: there was an allometric negative relationship between density of sprouts and mean biomass of survivors during all sampling periods in genets without neighbours in a 1-m radius; the self-thinning trajectory of sprouts in genets without neighbours in a 2-m radius was short, a net increase in sprouts per stump area was accompanied by an increase in mean sprout biomass 30 months after clipping. During the same period, however, plants with neighbours showed a decline in both the sprout biomass and density.     

The evolution of adult height in Europe: A brief note

This paper presents new evidence on the evolution of adult height in 10 European countries for cohorts born between 1950 and 1980 using the European Community Household Panel (ECHP), which collects height data from Austria, Belgium, Denmark, Finland, Greece, Ireland, Italy, Portugal, Spain, and Sweden. Our findings show a gradual increase in adult height across all countries. However, countries from Southern Europe (Greece, Italy, Portugal, and Spain) experienced greater gains in stature than those located in Northern Europe (Austria, Belgium, Denmark, Finland, Ireland, and Sweden).     

Identification of a new locus and validation of previously reported loci showing differential methylation associated with smoking. The REGICOR study

Smoking increases the risk of many diseases and could act through changes in DNA methylation patterns. The aims of this study were to determine the association between smoking and DNA methylation throughout the genome at cytosine-phosphate-guanine (CpG) site level and genomic regions. A discovery cross-sectional epigenome-wide association study nested in the follow-up of the REGICOR cohort was designed and included 645 individuals. Blood DNA methylation was assessed using the Illumina HumanMethylation450 BeadChip. Smoking status was self-reported using a standardized questionnaire. We identified 66 differentially methylated CpG sites associated with smoking, located in 38 genes. In most of these CpG sites, we observed a trend among those quitting smoking to recover methylation levels typical of never smokers. A CpG site located in a novel smoking-associated gene (cg06394460 in LNX2) was hypomethylated in current smokers. Moreover, we validated two previously reported CpG sites (cg05886626 in THBS1, and cg24838345 in MTSS1) for their potential relation to atherosclerosis and cancer diseases, using several different approaches: CpG site methylation, gene expression, and plasma protein level determinations. Smoking was also associated with higher THBS1 gene expression but with lower levels of thrombospondin-1 in plasma. Finally, we identified differential methylation regions in 13 genes and in four non-coding RNAs. In summary, this study replicated previous findings and identified and validated a new CpG site located in LNX2 associated with smoking.     

HPTLC and GC/MS Study of Amaryllidaceae Alkaloids of Two Narcissus Species

In this article, we report on the alkaloid profile and dynamic of alkaloid content and diversity in two Narcissus plants at different stages of development. The alkaloid profile of the two Narcissus species was investigated by GC/MS and HPTLC. Fifty eight Amaryllidaceae alkaloids were detected, and 25 of them were identified in the different organs of N. tazetta and N. papyraceus. The alkaloid 3‐O‐methyl‐9‐O‐demethylmaritidine is tentatively identified here for the first time from the Amaryllidaceae family, and four alkaloids (tazettamide, sternbergine, 1‐O‐acetyllycorine, 2,11‐didehydro‐2‐dehydroxylycorine) are tentatively identified for the first time in the genus Narcissus. The different organs of the two species analyzed showed remarkable differences in their alkaloid pattern, type of biosynthesis, main alkaloid and number of alkaloids. Lycorine‐type alkaloids dominated the alkaloid, metabolism in N. papyraceus, while alkaloids of narciclasine‐, galanthamine‐ and homolycorine‐types were found only in the species N. tazetta L.     

Bacterial inclusion bodies: making gold from waste

Many protein species produced in recombinant bacteria aggregate as insoluble protein clusters named inclusion bodies (IBs). IBs are discarded from further processing or are eventually used as a pure protein source for in vitro refolding. Although usually considered as waste byproducts of protein production, recent insights into the physiology of recombinant bacteria and the molecular architecture of IBs have revealed that these protein particles are unexpected functional materials. In this Opinion article, we present the relevant mechanical properties of IBs and discuss the ways in which they can be explored as biocompatible nanostructured materials, mainly, but not exclusively, in biocatalysis and tissue engineering.     

Effect of nutrition and Enteromyxum leei infection on gilthead sea bream Sparus aurata intestinal carbohydrate distribution

The effect of a practical plant protein-based diet containing vegetable oils (VO) as the major lipid source on the mucosal carbohydrate pattern of the intestine was studied in gilthead sea bream Sparus aurata challenged with the myxosporean parasite Enteromyxum leei. Fish fed for 9 mo either a fish oil (FO) diet or a blend of VO at 66% of replacement (66VO diet) were exposed to parasite-contaminated water effluent. Samples of the anterior, middle and posterior intestine (AI, MI and PI, respectively) were obtained for parasite diagnosis and histochemistry. Fish were categorised as control (C, not exposed), early (E) or late (L) infected. Mucin and lectin histochemistry was applied to detect the different types of mucins and sialic acid in goblet cells (GC), the brush border and enterocytes. The number of GC stained with periodic acid Schiff (PAS), alcian blue (AB), aldehyde fuchsin-alcian blue (AF-AB), for the detection of neutral, acidic, sulphated and carboxylic mucins, and with the lectin Sambucus nigra agglutinin (SNA), were counted in digital images. The 66VO diet produced a significant decrease of GC with neutral and acidic mucins in the AI and MI, and also of those with carboxylic mucins and sialic acid in the MI. Sulphated mucins and sialic acid were less abundant in the AI than in the MI and PI in the C-66VO treatment. E. leei infection had a strong effect on the number of GC, as E and L infected fish had a significant decrease of GC positive for all the stains versus C fish in PI. Time and diet effects were also observed, since the lowest values were mostly registered in E-66VO fish in PI. In conclusion, though GC depletion was mainly induced by enteromyxosis, an effect of the diet was also observed. Thus, the diet can be a predisposing factor that worsens the disease course.     

Recombination gives a new insight in the effective population size and the history of the old world human populations

The information left by recombination in our genomes can be used to make inferences on our recent evolutionary history. Specifically, the number of past recombination events in a population sample is a function of its effective population size (Ne). We have applied a method, Identifying Recombination in Sequences (IRiS), to detect specific past recombination events in 30 Old World populations to infer their Ne. We have found that sub-Saharan African populations have an Ne that is approximately four times greater than those of non-African populations and that outside of Africa, South Asian populations had the largest Ne. We also observe that the patterns of recombinational diversity of these populations correlate with distance out of Africa if that distance is measured along a path crossing South Arabia. No such correlation is found through a Sinai route, suggesting that anatomically modern humans first left Africa through the Bab-el-Mandeb strait rather than through present Egypt.     

Network-level and population genetics analysis of the insulin/TOR signal transduction pathway across human populations

Genes and proteins rarely act in isolation, but they rather operate as components of complex networks of interacting molecules. Therefore, for understanding their evolution, it may be helpful to take into account the interaction networks in which they participate. It has been shown that selective constraints acting on genes depend on the position that they occupy in the network. Less understood is how the impact of local adaptation at the intraspecific level is affected by the network structure. Here, we analyzed the patterns of molecular evolution of 67 genes involved in the insulin/target of rapamycin (TOR) signal transduction pathway. This well-characterized pathway plays a key role in fundamental processes such as energetic metabolism, growth, reproduction, and aging and is involved in metabolic disorders such as obesity, insulin resistance, and diabetes. For that purpose, we combined genotype data from worldwide human populations with current knowledge of the structure and function of the pathway. We identified the footprint of recent positive selection in nine of the studied genomic regions. Most of the adaptation signals were observed among Middle East and North African, European, and Central South Asian populations. We found that positive selection preferentially targets the most central elements in the pathway, in contrast to previous observations in the whole human interactome. This observation indicates that the impact of positive selection on genes involved in the insulin/TOR pathway is affected by the pathway structure.     

Population abundance, structure and turnover estimates for leopard seals during winter dispersal combining tagging and photo-identification data

Winter dispersal in leopard seals is poorly understood because of its low density in most of its range. By combining photo-identification and tagging data from Bird Island, South Georgia, in mark-recapture models, leopard seal abundance over the winter of 2005 was estimated as 118 (95% CI: 78–179). Seasonal residents arrived earlier and stayed longer around the island (27 days; 95% CI: 23–32) and their numbers were low and stable over the winter Most of the seals (81; 95% CI: 31–130) were young transients, stayed only 1–7 days, and arrived later in the season. This suggests (1) very low predatory pressure upon the locally abundant prey populations; (2) two different patterns of winter movements: a winter migration in adult seals with long-term site fidelity, and large numbers of juveniles in dispersal possibly attracted by locally abundant prey colonies, and potentially influenced by increased environmental stress.