Y chromosome haplogroups of elite Ethiopian endurance runners

Favourable genetic endowment has been proposed as part of the explanation for the success of East African endurance athletes, but no evidence has yet been presented. The Y chromosome haplogroup distribution of elite Ethiopian athletes (n=62) was compared with that of the general Ethiopian population (n=95) and a control group from Arsi (a region producing a disproportionate number of athletes; n=85). Athletes belonged to three groups: marathon runners (M; n=23), 5–km to 10–km runners (5–10K; n=21) and other track and field athletes (TF; n=18). DNA was extracted from buccal swabs and haplogroups were assigned after the typing of binary markers in multiplexed minisequencing reactions. Frequency differences between groups were assessed by using contingency exact tests and showed that Y chromosome haplogroups are not distributed amongst elite Ethiopian endurance runners in the same proportions as in the general population, with statistically significant (P<0.05) differences being found in four of the individual haplogroups. The geographical origins and languages of the athletes and controls suggest that these differences are less likely to be a reflection of population structure and that Y chromosome haplogroups may play a significant role in determining Ethiopian endurance running success.     

Plant-mycorrhizal fungi feedbacks: potential accomplices of <Emphasis Type="Italic">Avena barbata</Emphasis>’s high invasiveness

Alteration of the soil microbial communities can have important effects on plant invasion. The interdependence between plants and soil microbes could generate complex dynamics in which the composition of plant communities is regulated by the feedbacks of microbial communities on plant growth. In a greenhouse experiment we tested whether the soil microbes in roots of an invasive annual (Avena barbata, wild oat) and a native grass (Rytidosperma caespitosum, wallaby grass) can affect invasive and/or native plant performance. Individuals of each plant species were planted in sterilized soil to which pieces of roots of the same or the other species were added as a layer below the top soil. When plants were harvested after 10 weeks, the addition of roots of any species reduced the total biomass of wild oat. On the other hand, addition of roots of wild oat caused a much stronger reduction of the growth of wallaby grass, while roots of wallaby grass tended to increase its plant growth and shifted biomass allocation patterns. On balance, given the strength of the negative effects, our results indicated that invasion-induced changes in the soil microbial community could contribute to a displacement of the native grass. Thus, these changes might induce a positive feedback mechanism, contributing to the increased dominance of wild oat over wallaby grass in South Australian grasslands.     

Deletion polymorphism in the gene for angiotensin converting enzyme is associated with elevated fasting blood glucose levels

The frequency and distribution of angiotensin converting enzyme insertion/deletion (ACE I/D) polymorphism, and its association with other known risk factors for coronary atherosclerosis, has been studied, in a normal south Italian population. Subjects homozygous for deletion showed elevated fasting blood glucose levels when compared with subjects homozygous for insertion. The difference was consistent with an increased number of type 2 diabetics among the former group of subjects.Recipient of a post-doctoral fellowship from the Associazione Italiana Ricerca sul Cancro (A.I.R.C.)     

Interaction of Zn with Losartan. Activation of Intrinsic Apoptotic Signaling Pathway in Lung Cancer Cells and Effects on Alkaline and Acid Phosphatases

A new losartan [2-butyl-5-chloro-3-[[4-[2-(2H-tetrazol-5-yl)phenyl]phenyl]methyl]imidazol-4-yl]methanol zinc(II) complex [Zn(Los)Cl], was synthesized and characterized. The crystal structure was determined by x-ray diffraction methods. When aqueous solutions of the ligand and the metal were mixed, the known and more soluble powder [Zn(Los)₂].3H₂O (ZnLos) complex has been obtained. The interactions with phosphatases showed a concerted mechanism displayed by the Zn ions and ZnLos up to 500 μM concentration: a decrease of the acid phosphatase (AcP) associated with an increase in the alkaline phosphatase (ALP) activities. The complex and ZnSO₄ showed a cytotoxic behavior on human lung A549 cancer cell line at concentrations higher than 75 μM with reactive oxygen species (ROS) generation and GSH (and GSH/GSSG ratio) depletion. Apoptotic cells were observed using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) method, a mechanism accompanied by upregulation of BAX protein, downregulation of Bcl-XL and release of caspase-3. The BAX/Bcl-XL ratio was found to be significantly higher in cells exposure to ZnLos than cells treated with ZnSO₄, in agreement with the higher apoptotic percentage of cells found for the complex. Cell death was found to be produced by apoptosis and no necrosis has been observed. On the contrary, losartan exerted low effects on phosphatases, produced some reduction of cancer cell viability (concentrations >?250 μM, number of apoptotic cells similar to the basal) with low ROS depletion, without alteration of the GSH/GSSG and low BAX/Bcl-XL ratios. In the MRC-5, normal lung fibroblasts cell line only ZnSO₄ at concentrations higher than 200 μM displays cytotoxic effects.

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Graphical abstract Interaction of Zn with losartan. Activation of intrinsic apoptotic signaling pathway in lung cancer cells and effects on alkaline and acid phosphatases

     

Host-parasite association between <Emphasis Type="Italic">Didelphis albiventris</Emphasis> (Didelphimorphia: Didelphidae) and <Emphasis Type="Italic">Ixodes loricatus</Emphasis> (Acari: Ixodidae) in their southern ranges

The parasitism of Ixodes loricatus Neumann on white-eared opposum, Didelphis albiventris Lund, was analysed in the southern ranges of both. In central Argentina, 118 wild opossums were captured from 2005 to 2012. Adults of I. loricatus were collected (prevalence?=?66.1%, mean?=?7.03, median?=?4), but no immature stage. Tick infestation was not affected by sex (p?=?0.27) or age (p?=?0.37) of hosts. In line with previous studies about seasonality of larvae and nymphs of I. loricatus, adult tick infestation showed no seasonal trend. This lack of seasonal pattern of infestation for all parasitic stages of I. loricatus may indicate a life cycle governed by nidicolous behaviour, in such a way that this habit would contribute to minimize the influence of external environmental variables. The tick sex ratio was female biased, with two females per one male (p?=?0.002). The absence of I. loricatus immatures on D. albiventris suggests that in the study region there is clear segregation of immatures in rodents and adults in marsupials.     

In Vivo and In Vitro Detection of Luminescent and Fluorescent Lactobacillus reuteri and Application of Red Fluorescent mCherry for Assessing Plasmid Persistence

Lactobacillus reuteri is a symbiont that inhabits the gastrointestinal (GI) tract of mammals, and several strains are used as probiotics. After introduction of probiotic strains in a complex ecosystem like the GI tract, keeping track of them is a challenge. The main objectives of this study were to introduce reporter proteins that would enable in vivo and in vitro detection of L. reuteri and increase knowledge about its interactions with the host. We describe for the first time cloning of codon-optimized reporter genes encoding click beetle red luciferase (CBRluc) and red fluorescent protein mCherry in L. reuteri strains ATCC PTA 6475 and R2LC. The plasmid persistence of mCherry-expressing lactobacilli was evaluated by both flow cytometry (FCM) and conventional plate count (PC), and the plasmid loss rates measured by FCM were lower overall than those determined by PC. Neutralization of pH and longer induction duration significantly improved the mCherry signal. The persistency, dose-dependent signal intensity and localization of the recombinant bacteria in the GI tract of mice were studied with an in vivo imaging system (IVIS), which allowed us to detect fluorescence from 6475-CBRluc-mCherry given at a dose of 1×10¹⁰ CFU and luminescence signals at doses ranging from 1×10⁵ to 1×10¹⁰ CFU. Both 6475-CBRluc-mCherry and R2LC-CBRluc were localized in the colon 1 and 2 h after ingestion, but the majority of the latter were still found in the stomach, possibly reflecting niche specificity for R2LC. Finally, an in vitro experiment showed that mCherry-producing R2LC adhered efficiently to the intra cellular junctions of cultured IPEC-J2 cells. In conclusion, the two reporter genes CBRluc and mCherry were shown to be suitable markers for biophotonic imaging (BPI) of L. reuteri and may provide useful tools for future studies of in vivo and in vitro interactions between the bacteria and the host.     

New agricultural practices in the Loess Plateau of China do not reduce colonisation by arbuscular mycorrhizal or root invading fungi and do not carry a yield penalty

Agricultural practices aimed to reduce soil erosion and improve crop yield have been suggested to influence the activity of arbuscular mycorrhizal (AM) and root pathogenic fungi. We conducted a two-year field survey to investigate the effect of recently introduced agricultural practices on crop yield, AM colonisation and percentage isolation of root-invading fungi on the heavily eroded Loess Plateau of China. A rotation of maize (Zea mays L.), winter wheat (Triticum aestivum L.) and soybean (Glycine max L.) replaced monoculture of winter wheat. No-tillage (NT), and return of previous crop residues to the field in tilled (CTR) and non-tilled (NTR) systems replaced conventional tillage (CT). Yield, biomass and phosphorus content of the crops showed similar trends. Residue application increased yields of maize and soybean independent of tillage treatment in 2004, but only under CT in 2005. CT slightly increased maize yield. Neither residue application nor tillage treatment affected yield of wheat. None of the treatments influenced total percent isolation of root-invading fungi from wheat roots. The increase of some individual pathogenic fungi in NT did not translate into reduction of yield by disease. Importantly, the recommended practices did not have a penalty on yield while maintaining high levels of AM colonisation.     

Structures of two putative O-specific polysaccharides from the Rahnella aquatilis 3-95 lipopolysaccharide

Two polysaccharide preparations (OPSI and OPSII) were obtained by mild acid degradation of the lipopolysaccharide of Rahnella aquatilis 3-95. Studies by chemical methods and 1H and 13C NMR spectroscopy showed that OPSI is a linear alpha-D-mannan having a trisaccharide repeat and OPSII is a approximately 2:1 mixture of the same mannan and an alpha-d-glucan: