How Does Selfing Affect the Pace and Process of Speciation?

Surprisingly little attention has been given to the impact of selfing on speciation, even though selfing reduces gene flow between populations and affects other key population genetics parameters. Here we review recent theoretical work and compile empirical data from crossing experiments and genomic and phylogenetic studies to assess the effect of mating systems on the speciation process. In accordance with theoretical predictions, we find that accumulation of hybrid incompatibilities seems to be accelerated in selfers, but there is so far limited empirical support for a predicted bias toward underdominant loci. Phylogenetic evidence is scarce and contradictory, including studies suggesting that selfing either promotes or hampers speciation rate. Further studies are therefore required, which in addition to measures of reproductive barrier strength and selfing rate should routinely include estimates of demographic history and genetic divergence as a proxy for divergence time.

Access to novel cancer medicines in four countries in Central and Eastern Europe in relation to clinical benefit.

BACKGROUND: Almost 100 novel cancer medicines have been approved in Europe over the last decade. Limited public health care resources in countries in Central and Eastern Europe (CEE) call for a prioritization of access to effective medicines. We investigated how both reimbursement status and waiting time to reimbursement correlate with the magnitude of clinical benefit provided by novel medicines in four selected countries (Czechia, Hungary, Poland, and Slovakia). MATERIALS AND METHODS: A total of 124 indications of 51 cancer medicines with marketing authorization by the European Medicines Agency in 2011-2020 were included and followed up until 2022. Data on reimbursement status and waiting time to reimbursement (i.e. time from marketing authorization to national reimbursement approval) were collected for each country. Data were analyzed in relation to clinical benefit status (i.e. substantial versus nonsubstantial clinical benefit) of indications according to the European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS). RESULTS: The degree of reimbursement differed between countries with 64% of indications with reimbursement in Czechia, 40% in Hungary, 51% in Poland, and 19% in Slovakia. In all countries, a significantly greater proportion of indications with a substantial clinical benefit was reimbursed (P < 0.05). The median waiting time to reimbursement ranged from 27 months in Poland to 37 months in Hungary. No significant differences in waiting time in relation to clinical benefit were observed in any country (P = 0.25-0.84). CONCLUSIONS: Cancer medicines with a substantial clinical benefit are more likely to be reimbursed in all four CEE countries. Waiting times to reimbursement are equally long for medicines with or without a substantial clinical benefit, indicating a lack of prioritization of fast access to medicines delivering a substantial benefit. Incorporation of the ESMO-MCBS in reimbursement assessments and decisions could aid in better utilization of limited resources to deliver more effective cancer care.

The Small GTPase Rab7 Regulates Release of Mitochondria in Extracellular Vesicles in Response to Lysosomal Dysfunction.

Mitochondrial quality control is critical for cardiac homeostasis as these organelles are responsible for generating most of the energy needed to sustain contraction. Dysfunctional mitochondria are normally degraded via intracellular degradation pathways that converge on the lysosome. Here, we identified an alternative mechanism to eliminate mitochondria when lysosomal function is compromised. We show that lysosomal inhibition leads to increased secretion of mitochondria in large extracellular vesicles (EVs). The EVs are produced in multivesicular bodies, and their release is independent of autophagy. Deletion of the small GTPase Rab7 in cells or adult mouse heart leads to increased secretion of EVs containing ubiquitinated cargos, including intact mitochondria. The secreted EVs are captured by macrophages without activating inflammation. Hearts from aged mice or Danon disease patients have increased levels of secreted EVs containing mitochondria indicating activation of vesicular release during cardiac pathophysiology. Overall, these findings establish that mitochondria are eliminated in large EVs through the endosomal pathway when lysosomal degradation is inhibited.

What can cold-induced transcriptomes of Arctic Brassicaceae tell us about the evolution of cold tolerance?

Little is known about the evolution of cold tolerance in polar plant species and how they differ from temperate relatives. To gain insight into their biology and the evolution of cold tolerance, we compared the molecular basis of cold response in three Arctic Brassicaceae species. We conducted a comparative time series experiment to examine transcriptional responses to low temperature. RNA was sampled at 22°C, and after 3, 6, and 24 at 2°C. We then identified sets of genes that were differentially expressed in response to cold and compared them between species, as well as to published data from the temperate Arabidopsis thaliana. Most differentially expressed genes were species-specific, but a significant portion of the cold response was also shared among species. Among thousands of differentially expressed genes, ~200 were shared among the three Arctic species and A. thaliana, while ~100 were exclusively shared among the three Arctic species. Our results show that cold response differs markedly between Arctic Brassicaceae species, but probably builds on a conserved basis found across the family. They also confirm that highly polygenic traits such as cold tolerance may show little repeatability in their patterns of adaptation.

Rapid evolution of post-zygotic reproductive isolation is widespread in Arctic plant lineages.

BACKGROUND AND AIMS: The Arctic tundra, with its extreme temperatures and short growing season, is evolutionarily young and harbours one of the most species-poor floras on Earth. Arctic species often show little phenotypic and genetic divergence across circumpolar ranges. However, strong intraspecific post-zygotic reproductive isolation (RI) in terms of hybrid sterility has frequently evolved within selfing Arctic species of the genus Draba. Here we assess whether incipient biological species are common in the Arctic flora. METHODS: We conducted an extensive crossing experiment including six species representing four phylogenetically distant families collected across the circumpolar Arctic. We crossed conspecific parental populations representing different spatial scales, raised 740 F1 hybrids to maturity and measured fertility under laboratory conditions. We examined genetic divergence between populations for two of these species (Cardamine bellidifolia and Ranunculus pygmaeus). KEY RESULTS: In five of the six species, we find extensive reduction in pollen fertility and seed set in F1 hybrids; 219 (46 %) of the 477 F1 hybrids generated between parents separated by ≥427 km had <20 % pollen fertility. Isolation with migration (IM) and *BEAST analyses of sequences of eight nuclear genes in C. bellidifolia suggests that reproductively isolated populations of this species diverged during, or even after, the last glaciation. Likewise, Arctic populations of R. pygmaeus were genetically very similar despite exhibiting strongly reduced fertility in crosses, suggesting that RI evolved recently also in this species. CONCLUSION: We show that post-zygotic RI has developed multiple times within taxonomically recognized Arctic species belonging to several distantly related lineages, and that RI may have developed over just a few millennia. Rapid and widespread evolution of incipient biological species in the Arctic flora might be associated with frequent bottlenecks due to glacial cycles, and/or selfing mating systems, which are common in the harsh Arctic environment where pollinators are scarce.

Divergence in red light responses associated with thermal reversion of phytochrome B between high- and low-latitude species.

Phytochromes play a central role in mediating adaptive responses to light and temperature throughout plant life cycles. Despite evidence for adaptive importance of natural variation in phytochromes, little information is known about molecular mechanisms that modulate physiological responses of phytochromes in nature. We show evolutionary divergence in physiological responses relevant to thermal stability of a physiologically active form of phytochrome (Pfr) between two sister species of Brassicaceae growing at different latitudes. The higher latitude species (Cardamine bellidifolia; Cb) responded more strongly to light-limited conditions compared with its lower latitude sister (C. nipponica; Cn). Moreover, CbPHYB conferred stronger responses to both light-limited and warm conditions in the phyB-deficient mutant of Arabidopsis thaliana than CnPHYB: that is Pfr CbphyB was more stable in nuclei than CnphyB. Our findings suggest that fine tuning Pfr stability is a fundamental mechanism for plants to optimise phytochrome-related traits in their evolution and adapt to spatially varying environments, and open a new avenue to understand molecular mechanisms that fine tune phytochrome responses in nature.

Multiple Genetic Trajectories to Extreme Abiotic Stress Adaptation in Arctic Brassicaceae.

Extreme environments offer powerful opportunities to study how different organisms have adapted to similar selection pressures at the molecular level. Arctic plants have adapted to some of the coldest and driest biomes on Earth and typically possess suites of similar morphological and physiological adaptations to extremes in light and temperature. Here, we compare patterns of molecular evolution in three Brassicaceae species that have independently colonized the Arctic and present some of the first genetic evidence for plant adaptations to the Arctic environment. By testing for positive selection and identifying convergent substitutions in orthologous gene alignments for a total of 15 Brassicaceae species, we find that positive selection has been acting on different genes, but similar functional pathways in the three Arctic lineages. The positively selected gene sets identified in the three Arctic species showed convergent functional profiles associated with extreme abiotic stress characteristic of the Arctic. However, there was little evidence for independently fixed mutations at the same sites and for positive selection acting on the same genes. The three species appear to have evolved similar suites of adaptations by modifying different components in similar stress response pathways, implying that there could be many genetic trajectories for adaptation to the Arctic environment. By identifying candidate genes and functional pathways potentially involved in Arctic adaptation, our results provide a framework for future studies aimed at testing for the existence of a functional syndrome of Arctic adaptation in the Brassicaceae and perhaps flowering plants in general.

Associations among Periodontitis, Calcified Carotid Artery Atheromas, and Risk of Myocardial Infarction.

Cardiovascular disease is a common cause of morbidity and premature mortality. Cardiovascular disease can be prevented when risk factors are identified early. Calcified carotid artery atheromas (CCAAs), detected in panoramic radiographs, and periodontitis have both been associated with increased risk of cardiovascular disease. This case-control study aimed to 1) investigate associations between periodontitis and CCAA detected in panoramic radiographs and 2) determine the risk of future myocardial infarctions due to CCAA combined with periodontitis. We evaluated 1,482 participants (738 cases and 744 controls) with periodontitis and CCAAs recruited from the PAROKRANK study (Periodontitis and Its Relation to Coronary Artery Disease). Participants were examined with panoramic radiographs, including the carotid regions. Associations between myocardial infarction and periodontitis combined with CCAA were evaluated in 696 cases and 696 age-, sex-, and residential area-matched controls. Periodontitis was evaluated radiographically (as degree of bone loss) and with a clinical periodontal disease index score (from clinical and radiographic assessments). We found associations between CCAA and clinical periodontal disease index score among cases (odds ratio [OR], 1.51; 95% CI, 1.09 to 2.10; P = 0.02) and controls (OR, 1.70; 95% CI, 1.22 to 2.38; P < 0.01), although not between CCAA and the degree of bone loss. In a multivariable model, myocardial infarction was associated with CCAA combined with periodontitis, as assessed by degree of bone loss (OR, 1.75; 95% CI, 1.11 to 2.74; P = 0.01). When the cohort was stratified by sex, only men showed a significant association between myocardial infarction and CCAA combined with periodontitis. Participants with clinically diagnosed periodontitis exhibited CCAA in panoramic radiographs more often than those without periodontitis, irrespective of the presence of a recent myocardial infarction. Participants with combined periodontitis and CCAA had a higher risk of having had myocardial infarction as compared with participants with either condition alone. These findings implied that patients in dental care might benefit from dentists assessing panoramic radiographs for CCAA-particularly, patients with periodontitis who have not received any preventive measures for cardiovascular disease.

Tear staining in finisher pigs and its relation to age, growth, sex and potential pen level stressors.

Tear staining (TS) in the pig has been related to different stressors and may be a useful tool for assessing animal welfare on farm. The aim of the current study was to investigate TS across the finisher period and its possible relation to age, growth, sex and experimentally induced stressors. The study included 80 finisher pens divided between three batches. Within each batch, the pens either included pigs with docked or undocked tails, had straw provided (150 g/pig/day) or not and had a low (1.21 m2/pig, 11 pigs) or high stocking density (0.73 m2/pig, 18 pigs). Tear staining (scores 1 to 4; from smaller to larger tear stain area, respectively) and tail damage were scored on each individual pig three times per week over the 9-week study period, and the individual maximum TS score within each week was chosen for further analysis. Data were analysed using logistic regression separately for each of the four possible TS score levels. The TS scores 1 and 2 decreased with weeks into the study period and were negatively related to the average daily gain (ADG) of the pigs, whereas the TS score 4 increased with weeks into the study period and was positively related to ADG. None of the TS scores differed between females and castrated males, and neither straw provision nor lowering the stocking density affected the TS scores. However, the TS score 1 decreased the last week before an event of tail damage (at least one pig in the pen with a bleeding tail wound), whereas the TS score 4 increased. The results of the current study advocates for a relation between TS and the factors such as age, growth and stress in the pig, while no relation was found between TS and the environmental factors straw provision and lowered stocking density. The relations to age and growth are important to take into consideration if using TS as a welfare assessment measure in the pig in the future.

Leaky gut biomarkers in depression and suicidal behavior.

OBJECTIVE: Inflammation is associated with major depressive disorder (MDD) and suicidal behavior. According to the 'leaky gut hypothesis', increased intestinal permeability may contribute to this relationship via bacterial translocation across enterocytes. We measured plasma levels of gut permeability markers, in patients with a recent suicide attempt (rSA), MDD subjects with no history of a suicide attempt (nsMDD), and healthy controls (HC), and related these markers to symptom severity and inflammation. METHOD: We enrolled rSA (n = 54), nsMDD (n = 13), and HC (n = 17). Zonulin, intestinal fatty acid binding protein (I-FABP), soluble CD14, and interleukin-6 (IL-6) were quantified in plasma. Montgomery-Åsberg Depression Rating Scale (MADRS) and Suicide Assessment Scale (SUAS) were used for symptom assessments. RESULTS: The rSA group displayed higher I-FABP and lower zonulin levels compared with both the nsMDD and the HC groups (all P < 0.001). IL-6 correlated positively with I-FABP (r = 0.24, P < 0.05) and negatively with zonulin (r = -0.25, P < 0.05). In all subjects, I-FABP levels correlated positively with MADRS (r = 0.25, P < 0.05) and SUAS scores (r = 0.38, P < 0.001), and the latter correlation was significant also in the nsMDD group (r = 0.60, P < 0.05). CONCLUSION: The 'leaky gut hypothesis' may improve our understanding of the link between inflammation and suicidal behavior. These findings should be considered preliminary until replicated in larger cohorts.

A Guide to Carrying Out a Phylogenomic Target Sequence Capture Project.

High-throughput DNA sequencing techniques enable time- and cost-effective sequencing of large portions of the genome. Instead of sequencing and annotating whole genomes, many phylogenetic studies focus sequencing effort on large sets of pre-selected loci, which further reduces costs and bioinformatic challenges while increasing coverage. One common approach that enriches loci before sequencing is often referred to as target sequence capture. This technique has been shown to be applicable to phylogenetic studies of greatly varying evolutionary depth. Moreover, it has proven to produce powerful, large multi-locus DNA sequence datasets suitable for phylogenetic analyses. However, target capture requires careful considerations, which may greatly affect the success of experiments. Here we provide a simple flowchart for designing phylogenomic target capture experiments. We discuss necessary decisions from the identification of target loci to the final bioinformatic processing of sequence data. We outline challenges and solutions related to the taxonomic scope, sample quality, and available genomic resources of target capture projects. We hope this review will serve as a useful roadmap for designing and carrying out successful phylogenetic target capture studies.

Autophagy-A key pathway for cardiac health and longevity.

As average life expectancy continues to rise in the developed world, age-associated pathologies are increasing in prevalence. The hallmarks of cardiac ageing include cardiomyocyte loss, fibrosis and hypertrophy, all of which contribute to an increased incidence of cardiac disease. At the molecular level, cellular ageing is characterized by increased ROS production, mitochondrial dysfunction and the accumulation of damaged proteins and organelles. Cardiomyocytes and other senescent cell types rely upon autophagy, a lysosome-mediated degradation pathway, to remove potentially toxic protein aggregates and damaged organelles from the cellular milieu. However, increasing lines of evidence point to an age-associated decrease in cardiomyocyte autophagy, with predictably negative consequences for cardiac function and health. Conversely, stimulation of autophagy has been shown to improve cellular health and cardiac function and to increase lifespan in numerous model organisms. Clearly, autophagy represents a critical pathway for cellular vitality, as well as a promising therapeutic target for the treatment of age-related cardiac pathologies. In this review, we will discuss the mechanism of autophagy and its regulation in the cell, the role of autophagy in the ageing heart, and how the autophagy pathway might be targeted to improve cardiac health.

Invasive Dental Treatment and Risk for a First Myocardial Infarction.

Invasive dental treatment is suggested to be associated with an increased risk for the development of cardiovascular events. We tested the hypothesis that the incidence of a first myocardial infarction (MI) within 4 wk after invasive dental treatments is increased. A registry-based case-control study within nationwide health care and population registries in Sweden was performed. The case patients included 51,880 individuals with a first fatal or nonfatal MI between January 2011 and December 2013. For each case, 5 control subjects, free from prior MI and matched for age, sex, and geographic area of residence, were randomly selected from the national population registry through risk set sampling with replacement, resulting in 246,978 control subjects. Information on dental treatments was obtained from the Dental Health Register, and the procedures were categorized into invasive dental treatments or other dental treatments. Conditional logistic regression was used to estimate odds ratios (ORs) for MI with corresponding 95% confidence intervals (CIs). In addition to the matching variables, adjustments were made for the following confounders: diabetes, previous cardiovascular disease (CVD), CVD drug treatment, education, and income. The mean age for case patients and controls subjects was 72.6 ± 13.0 y and 72.3 ± 13.0 y, respectively. Case patients more often had previous CVD (49% vs. 23%; P < 0.001) and diabetes (19% vs. 11%; P < 0.001) and received more treatment with CVD drugs (68% vs. 56%; P < 0.001) than control subjects. There was no association between invasive dental treatments during the 4 wk preceding the MI index date (crude OR = 0.99; 95% CI, 0.92 to 1.06; adjusted for confounders OR = 0.98; 95% CI, 0.91 to 1.06). This study did not support the hypothesis of an increased incidence of MI after recent invasive dental treatment.

Severe Periodontitis Is Associated with Myocardial Infarction in Females.

The aim of the present study was to test the hypothesis that there is a sex difference in the association between periodontitis (PD) and a first myocardial infarction (MI). The analysis in the case-control study was based on 785 patients (147 females and 638 males) with a first MI and 792 matched controls (147 females and 645 males), screened for cardiovascular risk factors and subjected to a panoramic dental X-ray. Periodontal status was defined by alveolar bone loss and diagnosed as no PD (≥80% remaining alveolar bone), mild to moderate PD (66% to 79%), or severe PD (<66%). Logistic regression was used when analyzing PD as a risk factor for MI, adjusting for age, smoking, diabetes, education, and marital status. The mean age was 64 ± 7 y for females and 62 ± 8 y for males. Severe PD was more common in female patients than female controls (14 vs. 4%, P = 0.005), with an increased risk for severe PD among female patients with a first MI (odds ratio [OR] = 3.92, 95% confidence interval [CI] =1.53 to 10.00, P = 0.005), which remained (OR = 3.72, 95% CI = 1.24 to 11.16, P = 0.005) after adjustments. Male patients had more severe PD (7% vs. 4%; P = 0.005) than male controls and an increased risk for severe PD (OR = 1.88, 95% CI = 1.14 to 3.11, P = 0.005), but this association did not remain following adjustment (OR = 1.67, 95% CI = 0.97 to 2.84, NS). Severe PD was associated with MI in both females and males. After adjustments for relevant confounders, this association did, however, remain only in females. These data underline the importance of considering poor dental health when evaluating cardiovascular risk, especially in females.

Fluctuating potentials in GaAs:Si nanowires: critical reduction of the influence of polytypism on the electronic structure.

In this work, the effects of Si doping in GaAs nanowires (NWs) grown on GaAs (111)B by molecular beam epitaxy with different Si doping levels (nominal free carrier concentrations of 1 × 1016, 8 × 1016, 1 × 1018 and 5 × 1018 cm-3) are deeply investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), grazing incidence X-ray diffraction (GID), photoluminescence (PL) and cathadoluminescence (CL). TEM results reveal a mixture of wurtzite (WZ) and zinc-blende (ZB) segments along the NW axis independently of the Si doping levels. GID measurements suggest a slight increase of the ZB fraction with the Si doping. Low temperature PL and CL spectra exhibit sharp lines in the energy range 1.41-1.48 eV, for the samples with lower Si doping levels. However, the emission intensity increases and is accompanied by a clear broadening of the observed lines for the samples with higher Si doping levels. The staggered type-II band alignment only determines the optical properties of the lower doping levels in GaAs:Si NWs. For the higher Si doping levels, the electronic energy level structure of the NWs is determined by electrostatic fluctuating potentials intimately related to the amphoteric behavior of the Si dopant in GaAs. For the heavily doped NWs, the estimated depth of the potential wells is ∼96-117 meV. Our results reveal that the occurrence of the fluctuating potentials is not dependent on the crystalline phase and shows that the limitation imposed by the polytypism can be overcome.

Activity of inflammatory bowel disease influences the expression of cytokines in gingival tissue.

This study assessed the cytokine expression in gingival and intestinal tissues from periodontitis patients with inflammatory bowel disease (IBD) and evaluated if IBD activity is a covariate to the amount of gingival cytokines. Paired gingival and intestinal tissues were collected from 21 patients and homogenised using a cell disruptor. Cytokine expression (IL-1ß, IL-4, IL-6, IL-10, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IL-17A, IL-17F, IFN-γ, sCD40L, and TNF-α) was evaluated using bead-based multiplex technology. An inflammation score was developed using the intestinal cytokines that showed good accuracy to discriminate IBD active patients from those in remission and then a similar score was applied to gingival tissue. IL-4, IL-10 and IL-21 expressions were significantly increased in gingival tissue from patients with an active disease as compared to those with a disease in remission. The inflammation score (mean value of IL-1ß, IL-6, IL-21, and sCD40L) was significantly higher in gingival tissue from patients with IBD activity. There was a significant correlation between gingival and intestinal inflammation scores (rho=0.548; P=0.01). Significantly higher IL-23 and IFN-γ levels and lower IL-31 and TNF-α levels were observed in gingival tissues than in intestinal ones. Activity of inflammatory bowel disease influenced the cytokine expression in gingival tissue.

Antimicrobial activity of polyhexamethylene guanidine phosphate in comparison to chlorhexidine using the quantitative suspension method.

BACKGROUND: Polyhexamethylene guanidine phosphate (PHMG-P) belongs to the polymeric guanidine family of biocides and contains a phosphate group, which may confer better solubility, a detoxifying effect and may change the kinetics and dynamics of PHMG-P interactions with microorganisms. Limited data regarding PHMG-P activity against periodontopathogenic and cariogenic microorganisms necessitates studies in this area. Aim is to evaluate polyhexamethylene guanidine phosphate antimicrobial activity in comparison to chlorhexidine. METHODS: Quantitative suspension method was used enrolling Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans and Lactobacillus acidophilus. RESULTS: Both tested antiseptics at their clinically-used concentrations, of 0.2% (w/v) and 1% (w/v), correspondingly provided swift bactericidal effects against S. aureus, P. aeruginosa, E. coli and C. albicans, A. actinomycetemcomitans and P. gingivalis with reduction factors higher than 6.0. Diluted polyhexamethylene guanidine phosphate and chlorhexidine to 0.05% continued to display anti-bacterial activity and decreased titers of standard quality control, periopathogens to below 1.0 × 10(3) colony forming units/ml, albeit requiring prolonged exposure time. To achieve a bactericidal effect against S. mutans, both antiseptics at all concentrations required a longer exposure time. We found that a clinically-used 1% of polyhexamethylene guanidine phosphate concentration did not have activity against L. acidophilus. CONCLUSION: High RF of polyhexamethylene guanidine phosphate and retention of bactericidal effects, even at 0.05%, support the use of polyhexamethylene guanidine phosphate as a biocide with sufficient anti-microbial activity against periopathogens. Polyhexamethylene guanidine phosphate displayed bactericidal activity against periopathogens and S. mutans and could potentially be applied in the management of oral diseases.

Evaluation of barrier materials for removing pollutants from groundwater rich in natural organic matter.

Permeable barriers are used for passive remediation of groundwater and can be constructed from a range of materials. The optimal material depends on the types of contaminants and physico-chemical parameters present at the site, as well as the hydraulic conductivity, environmental safety, availability, cost and long-term stability of the material itself. The aim of the presented study was to test a number of materials for their ability to remove heavy metals and organic pollutants from groundwater with a high (140 mg L(-1)) content of natural organic matter (NOM). The following materials were included in the study: sand, peat, fly ash, iron powder, lignin and combinations thereof. Polluted water was fed into glass columns loaded with each sorbent and the contaminant removal efficiency of the material was evaluated through chemical analysis of the percolate. Materials based on fly ash and zero-valent iron were found to be the most effective for heavy metal removal, while fly ash and peat were the most effective for removing aliphatic compounds. Filtration through lignin and peat led to leaching of NOM. Although the leaching decreased over time, it remained high throughout the experiments. The results indicate that remediation of contaminated land at disused industrial sites is a complex task that often requires the use of mixed materials or a minimum of two sequential barriers.

Genetics of cryptic speciation within an Arctic mustard, Draba nivalis.

Crossing experiments indicate that hybrid sterility barriers frequently have developed within diploid, circumpolar plant species of the genus Draba. To gain insight into the rapid evolution of postzygotic reproductive isolation in this system, we augmented the linkage map of one of these species, D. nivalis, and searched for quantitative trait loci (QTLs) associated with reproductive isolation. The map adds 63 new dominant markers to a previously published dataset of 31 co-dominant microsatellites. These markers include 52 amplified fragment length polymorphisms (AFLPs) and 11 sequence-specific amplified polymorphisms (SSAPs) based on retrotransposon sequence. 22 markers displaying transmission ratio distortion were further included in the map. We resolved eight linkage groups with a total map length of 894 cM. Significant genotype-trait associations, or quantitative trait loci (QTL), were detected for reproductive phenotypes including pollen fertility (4 QTLs), seed set (3 QTLs), flowering time (3 QTLs) and number of flowers (4 QTLs). Observed patterns of inheritance were consistent with the influence of both nuclear-nuclear interactions and chromosomal changes on these traits. All seed set QTLs and one pollen fertility QTL displayed underdominant effects suggestive of the involvement of chromosomal rearrangements in hybrid sterility. Interestingly, D. nivalis is predominantly self-fertilizing, which may facilitate the establishment of underdominant loci and contribute to reproductive isolation.

The impact of non-surgical periodontal treatment on serum levels of long chain-polyunsaturated fatty acids: a pilot randomized clinical trial.

BACKGROUND AND OBJECTIVE: Our group recently found higher levels of serum long chain-polyunsaturated fatty acids (LC-PUFAs) in patients with chronic periodontitis compared to controls. However, the effect of periodontal treatment on LC-PUFA serum levels has not been investigated. The primary aim of the present study was to investigate the impact of periodontal treatment on LC-PUFA serum levels. A secondary aim was to assess the effect of dietary ω-3 supplementation on clinical outcome. MATERIAL AND METHODS: The test group was composed of 10 patients with generalized chronic periodontitis (mean age 44 ± 6.4 years) treated with scaling and root planing associated with 4 mo of ω-3 supplementation eicosapetaenoic acid (EPA) plus docosahexaenoic acid (DHA), 3 g/d. The placebo group was composed of 11 patients (47.9 ± 10.5 years) that received scaling and root planing plus placebo. The periodontal examination included probing depth, clinical attachment level, bleeding on probing and visible plaque index. Docosapentaenoic acid (DPA), EPA, DHA and arachidonic acid (AA) were detected using gas chromatograph. RESULTS: In the placebo group, all LC-PUFAs levels reduced significantly (DHA, DPA and AA, p = 0.004; EPA, p = 0.008). In the test group, only DPA and AA showed a significant reduction (p = 0.005). Moreover, a significant decrease in the ratios AA/EPA and AA/DHA (p = 0.005) was observed in the test group. CONCLUSION: Non-surgical periodontal treatment reduced significantly the serum levels of all analyzed LC-PUFAs except those presented in the supplementation. The ω-3 dietary supplementation had no effect on clinical outcome of treatment.