SELECTION FOR ALTERNATIVE MALE REPRODUCTIVE TACTICS ALTERS INTRALOCUS SEXUAL CONFLICT

Intralocus sexual conflict (IASC) arises when fitness optima for a shared trait differ between the sexes; such conflict may help maintain genetic variation within populations. Sex‐limited expression of sexually antagonistic traits may help resolve the conflict, but the extent of this resolution remains a subject of debate. In species with alternative male reproductive tactics, unresolved conflict should manifest more in a more sexually dimorphic male phenotype. We tested this prediction in the bulb mite (Rhizoglyphus robini), a species in which aggressive fighters coexist with benign scramblers. To do this, we established replicated lines in which we increased the proportion of each of the alternative male morphs using artificial selection. After approximately 40 generations, the proportion of fighters and scramblers stabilized at >0.9 in fighter‐ and scrambler‐selected lines, respectively. We then measured several female fitness components. As predicted by IASC theory, female fecundity and longevity were lower in lines selected for fighters and higher in lines selected for scramblers. This finding indicates that sexually selected phenotypes are associated with an ontogenetic conflict that is not easily resolved. Furthermore, we suggest that IASC may be an important mechanism contributing to the maintenance of genetic variation in the expression of alternative reproductive tactics.     

Mites (Acari,Mesostigmata) in boreal Scots pine forest floors: effect of distance to stumps

Coarse woody debris (CWD) is a basic component of forest ecosystems and it plays a crucial role in species-poor boreal forests. Generally, previous studies have focused on differences between the forest floor and decaying logs of various tree species. The impact of distance to CWD has been investigated mainly for forest-floor snails and some groups of macrofauna, but not yet for mesostigmatid mites communities. We hypothesized that the effect of CWD decreases with increasing distance from CWD. To test this hypothesis we conducted a study in relatively species-poor Finnish boreal forest (at ca. 100 km northwest of Helsinki). In total, 81 samples were collected in 2007 from nine Scots pine (Pinus sylvestris) stumps, three microhabitats (CWD, soil/litter at 0.5 m from a stump and soil/litter at 1.5 m from a stump) and in three main directions (9 stumps × 3 microhabitats × 3 directions). Overall, 1965 mesostigmatid mites were collected representing 24 species. The mean number of mite species collected was significantly different between decaying stumps and forest litter; however, there was no significant difference between the litter samples at 0.5 and 1.5 m distance. The evenness index was significantly lower for samples collected from stumps than for litter in close (0.5 m) or far (1.5 m) distance. The most frequently encountered mite species were Veigaia nemorensis, Parazercon radiatus and Zercon zelawaiensis.     

Fine root classification matters: nutrient levels in different functional categories,orders and diameters of roots in boreal Pinus sylvestris across a latitudinal gradient

Plant and Soil - Any grouping of tree species concerned with SOC sequestration should include trees that are as homogeneous as possible in their carbon sequestration. We propose a classification of...     

The Endogenous and Cell Cycle-dependent Phosphorylation of tau Protein in Living Cells: Implications for Alzheimer’s Disease

In Alzheimer’s disease the neuronal microtubule-associated protein tau becomes highly phosphorylated, loses its binding properties, and aggregates into paired helical filaments. There is increasing evidence that the events leading to this hyperphosphorylation are related to mitotic mechanisms. Hence, we have analyzed the physiological phosphorylation of endogenous tau protein in metabolically labeled human neuroblastoma cells and in Chinese hamster ovary cells stably transfected with tau. In nonsynchronized cultures the phosphorylation pattern was remarkably similar in both cell lines, suggesting a similar balance of kinases and phosphatases with respect to tau. Using phosphopeptide mapping and sequencing we identified 17 phosphorylation sites comprising 80–90% of the total phosphate incorporated. Most of these are in SP or TP motifs, except S214 and S262. Since phosphorylation of microtubule-associated proteins increases during mitosis, concomitant with increased microtubule dynamics, we analyzed cells mitotically arrested with nocodazole. This revealed that S214 is a prominent phosphorylation site in metaphase, but not in interphase. Phosphorylation of this residue strongly decreases the tau–microtubule interaction in vitro, suppresses microtubule assembly, and may be a key factor in the observed detachment of tau from microtubules during mitosis. Since S214 is also phosphorylated in Alzheimer’s disease tau, our results support the view that reactivation of the cell cycle machinery is involved in tau hyperphosphorylation.     

Prostaglandins contribute to the vasodilation induced by nicotinic acid

The significance of endogenously formed prostaglandins in the vasodilation induced by nicotinic acid (NIC) was investigated. The forearm venous plasma level of radioimmunoassayed PGE (R-PGE) and the forearm blood flow (FBF) were measured in 13 healthy male volunteers at rest and during infusion of NIC. Each subject was subsequently re-studied after pretreatment with the PG synthesis inhibitor, naproxen. In the absence of naproxen, NIC infusion resulted in an almost four-fold rise in the release of R-PGE and a 60% increase in FBF. Pretreatment with naproxen did not affect the basal release of R-PGE or the basal FBF but inhibited both the release of R-PGE and the increase in FBF following NIC. The data support the hypothesis that the vasolidating effect of NIC is largely dependent upon an increased vascular formation of PG.     

Inheritance and linkage analysis of five enzyme loci in interspecific hybrids of toadlets,genus Bombina

Progeny produced from Bombina bombina, B. variegata, and field-collected interspecific hybrids have been analyzed for the inheritance of five enzyme loci, which are fixed for alternate alleles in the parental species. Lactate dehydrogenase (Ldh-1), NAD-dependent malate dehydrogenase (Mdh-1), creatine kinase (Ck), adenylate kinase (Ak), and glucosephosphate isomerase (Gpi) are all inherited in a Mendelian manner as codominant alleles at nuclear loci. Both parental alleles are equally functional in artificial F₁ hybrids (female B. bombina×male B. variegata) at each of the loci studied. No linkage between any pair of loci was observed. Discovery of this inherited biochemical variation combined with a technique for assaying individual genotypes without killing the animals makes feasible studies of hybrid population structure heretofore impossible.This work was partly supported by the Polish Academy of Sciences within the project MR-II/6.     

Long-term follow-up in adults after tetralogy of Fallot repair

Background

Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart disease and the population of ToF repair survivors is growing rapidly. Adults with repaired ToF develop late complications. The aim of this study was to describe and analyze long-term follow-up of patients with repaired ToF.

Methods

This is a retrospective cohort study. Consecutive 83 patients with repaired ToF who did not undergo pulmonary valve replacement were included. Mean age of all patients was 30.5?±?10.7. There were 49 (59%) male. Patients were divided into two groups according to the time since the repair (<?25 years and?≥?25 years). The electrocardiographic (ECG), cardiopulmonary exercise testing (CPET), echocardiographic and cardiac magnetic resonance (CMR) data were reviewed retrospectively.

Results

In CPET values were not significantly different in the two groups. In CMR volumes of left and right ventricles were not significantly different in the two groups. There were no differences between the groups in ventricular ejection fraction, mass of ventricles, or pulmonary regurgitation fraction. Among all the patients, ejection fraction and left and right ventricle mass, indexed pulmonary regurgitation volume measured by CMR did not correlate with the time since repair. In ECG among all the patients, ejection fraction of the RV, measured in CMR, negatively correlated with QRS duration (r?=???0.43; p?<?0.001). There was a positive correlation between QRS duration and end diastolic volume of the RV (r?=?0.30; p?<?0.02), indexed end diastolic volume of the RV (r?=?0.29; p?=?0.04), RV mass (r?=?0.36; p?<?0.001) and left ventricle mass (r?=?0.26; p?=?0.04).

Conclusion

Long-term survival and clinical condition after surgical correction of ToF in infancy is generally good and the late functional status in ToF – operated patients could be excellent up to 25 years after the repair. QRS duration could be an utility and easy factor to assessment of right ventricular function.

Trial registration

The study protocol was approved by the local Ethics Committee. Each participant provided informed consent to participate in the study (license number 122.6120.88.2016 from 28.04.2016).