Inferring the ecological and evolutionary determinants of community genetic diversity.

Understanding the relative contributions of ecological and evolutionary processes to the structuring of ecological communities is needed to improve our ability to predict how communities may respond to future changes in an increasingly human-modified world. Metabarcoding methods make it possible to gather population genetic data for all species within a community, unlocking a new axis of data to potentially unveil the origins and maintenance of biodiversity at local scales. Here, we present a new eco-evolutionary simulation model for investigating community assembly dynamics using metabarcoding data. The model makes joint predictions of species abundance, genetic variation, trait distributions and phylogenetic relationships under a wide range of parameter settings (e.g. high speciation/low dispersal or vice versa) and across a range of community states, from pristine and unmodified to heavily disturbed. We first demonstrate that parameters governing metacommunity and local community processes leave detectable signatures in simulated biodiversity data axes. Next, using a simulation-based machine learning approach we show that neutral and non-neutral models are distinguishable and that reasonable estimates of several model parameters within the local community can be obtained using only community-scale genetic data, while phylogenetic information is required to estimate those describing metacommunity dynamics. Finally, we apply the model to soil microarthropod metabarcoding data from the Troodos mountains of Cyprus, where we find that communities in widespread forest habitats are structured by neutral processes, while high-elevation and isolated habitats act as an abiotic filter generating non-neutral community structure. We implement our model within the ibiogen R package, a package dedicated to the investigation of island, and more generally community-scale, biodiversity using community-scale genetic data.

Community metabarcoding reveals the relative role of environmental filtering and spatial processes in metacommunity dynamics of soil microarthropods across a mosaic of montane forests.

Disentangling the relative role of environmental filtering and spatial processes in driving metacommunity structure across mountainous regions remains challenging, as the way we quantify spatial connectivity in topographically and environmentally heterogeneous landscapes can influence our perception of which process predominates. More empirical data sets are required to account for taxon- and context-dependency, but relevant research in understudied areas is often compromised by the taxonomic impediment. Here we used haplotype-level community DNA metabarcoding, enabled by stringent filtering of amplicon sequence variants (ASVs), to characterize metacommunity structure of soil microarthropod assemblages across a mosaic of five forest habitats on the Troodos mountain range in Cyprus. We found similar ß diversity patterns at ASV and species (OTU, operational taxonomic unit) levels, which pointed to a primary role of habitat filtering resulting in the existence of largely distinct metacommunities linked to different forest types. Within-habitat turnover was correlated to topoclimatic heterogeneity, again emphasizing the role of environmental filtering. However, when integrating landscape matrix information for the highly fragmented Quercus alnifolia habitat, we also detected a major role of spatial isolation determined by patch connectivity, indicating that stochastic and niche-based processes synergistically govern community assembly. Alpha diversity patterns varied between ASV and OTU levels, with OTU richness decreasing with elevation and ASV richness following a longitudinal gradient, potentially reflecting a decline of genetic diversity eastwards due to historical pressures. Our study demonstrates the utility of haplotype-level community metabarcoding for characterizing metacommunity structure of complex assemblages and improving our understanding of biodiversity dynamics across mountainous landscapes worldwide.

Collective and harmonized high throughput barcoding of insular arthropod biodiversity: Toward a Genomic Observatories Network for islands.

Current understanding of ecological and evolutionary processes underlying island biodiversity is heavily shaped by empirical data from plants and birds, although arthropods comprise the overwhelming majority of known animal species, and as such can provide key insights into processes governing biodiversity. Novel high throughput sequencing (HTS) approaches are now emerging as powerful tools to overcome limitations in the availability of arthropod biodiversity data, and hence provide insights into these processes. Here, we explored how these tools might be most effectively exploited for comprehensive and comparable inventory and monitoring of insular arthropod biodiversity. We first reviewed the strengths, limitations and potential synergies among existing approaches of high throughput barcode sequencing. We considered how this could be complemented with deep learning approaches applied to image analysis to study arthropod biodiversity. We then explored how these approaches could be implemented within the framework of an island Genomic Observatories Network (iGON) for the advancement of fundamental and applied understanding of island biodiversity. To this end, we identified seven island biology themes at the interface of ecology, evolution and conservation biology, within which collective and harmonized efforts in HTS arthropod inventory could yield significant advances in island biodiversity research.

A near-complete species-level phylogeny of uropeltid snakes harnessing historical museum collections as a DNA source.

Uropeltidae is a clade of small fossorial snakes (ca. 64 extant species) endemic to peninsular India and Sri Lanka. Uropeltid taxonomy has been confusing, and the status of some species has not been revised for over a century. Attempts to revise uropeltid systematics and undertake evolutionary studies have been hampered by incompletely sampled and incompletely resolved phylogenies. To address this issue, we take advantage of historical museum collections, including type specimens, and apply genome-wide shotgun (GWS) sequencing, along with recent field sampling (using Sanger sequencing) to establish a near-complete multilocus species-level phylogeny (ca. 87% complete at species level). This results in a phylogeny that supports the monophyly of all genera (if Brachyophidium is considered a junior synonym of Teretrurus), and provides a firm platform for future taxonomic revision. Sri Lankan uropeltids are probably monophyletic, indicating a single colonisation event of this island from Indian ancestors. However, the position of Rhinophis goweri (endemic to Eastern Ghats, southern India) is unclear and warrants further investigation, and evidence that it may nest within the Sri Lankan radiation indicates a possible recolonisation event. DNA sequence data and morphology suggest that currently recognised uropeltid species diversity is substantially underestimated. Our study highlights the benefits of integrating museum collections in molecular genetic analyses and their role in understanding the systematics and evolutionary history of understudied organismal groups.

Angiotensin-converting-enzyme insertion/deletion polymorphism, ACE activity, and COVID-19: A rather controversial hypothesis. A case-control study.

Accumulating data has shown a contribution of the renin-angiotensin system in COVID-19 pathogenesis. The role of angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) polymorphism as a risk factor in developing COVID-19 disease comes from epidemiological data and is controversially discussed. We conducted a retrospective case-control study and assessed the impact of ACE I/D genotype in COVID-19 disease prevalence and severity. In 81 COVID-19 patients explicitly characterized and 316 controls, recruited during the first wave of COVID-19 pandemic, ACE I/D genotype, and ACE activity were determined. A generalized linear model was used and Poisson regression analysis estimated the risk ratios (RRs) of alleles and genotypes for disease severity. DD patients had almost 2.0-fold increased risk (RR: 1.886, confidence limit [CL] 95%: 1.266-2.810, p = 0.0018) of developing a more severe disease when contrasted to ID and II individuals, as did D allele carriers compared to I carriers (RR: 1.372; CL 95%: 1.051-1.791; p = 0.0201). ACE activity (expressed as arbitrary units, AU/L) was lower in patients (3.62 ± 0.26) than in controls (4.65 ± 0.13) (p < 0.0001), and this reduction was observed mainly among DD patients compared to DD controls (3.97 ± 0.29 vs. 5.38 ± 0.21; p = 0.0014). Our results demonstrate that ACE DD genotype may predispose to COVID-19 increased disease severity via a mechanism associated, at least in part, with the significant fall in their ACE activity. Our findings suggest a more complex pattern of synergy between this polymorphism and ACE activity in COVID-19 patients compared to healthy individuals and set the grounds for large-scale studies assessing ACE genotype-based optimized therapies with ACE inhibitors and angiotensin receptor blockers.

The Impact of Vascular Loops in the Cerebellopontine Angle on Audio-Vestibular Symptoms: A Systematic Review.

It has been suggested that vascular loops in the cerebellopontine angle and internal auditory canal are involved in the etiology of audio-vestibular symptoms. Several studies have focused on the compression of the eighth cranial nerve by vascular loops but have yielded contradictory results regarding their clinical significance. The aim of this study was to investigate whether vascular loops in this region correlate with audio-vestibular symptoms and which loop features - if any - can potentially lead to symptom manifestation. This systematic review was conducted according to the PRISMA guidelines. We performed on PubMed a literature search from November 2005 to October 2020. The search strategy included the following keywords ("vascular loops" OR "AICA loops" OR "vascular compression syndrome") AND ("hearing loss" OR "tinnitus" OR "vertigo"). Fifteen studies were eligible and included in the analysis. Overall, the studies encompassed a total of 11,788 patients included in this review. The significantly larger group of patients (70%), in which no correlation of symptoms with vascular loops was found, suggests that vascular loops are probably anatomic variations in a substantial majority of cases with an uncommon subset causing some audio-vestibular symptoms. Even within the papers claiming a correlation, there is a multitude of symptoms that did not correlate with vascular loops. It has been suggested by most authors that magnetic resonance imaging should be performed to exclude the role of a vascular loop in the etiology of audio-vestibular symptoms only when vascular compression syndrome is suspected based on clinical indications and not routinely. Further studies would be useful in order to detail the relationship between the vascular structures and the nervous system.

Molecular and clinical profile of patients referred as Noonan or Noonan-like syndrome in Greece: a cohort of 86 patients.

Noonan syndrome (NS) is an autosomal dominant disorder characterized by clinical and genetic heterogeneity. It belongs to a wider group of pathologies, known as Rasopathies, due to the implication of genes encoding components of the Ras/MAPK signalling pathway. Recording the genetic alterations across populations helps assessing specific features to specific genes which is essential for better disease's recognition, prognosis and monitoring. Herein, we report the clinical and molecular data of a Greek cohort comprising of 86 NS or NS-like patients admitted at a single tertiary Centre in Athens, Greece. The analysis was performed using Sanger and next-generation sequencing, comprising 14 different genes. The mutational rates of the confirmed NS-associated genes in the Greek NS population are as follows: PTPN11 32.5%; RIT1 5.8%; SOS1 4.7%; BRAF 1.2%; CBL 1.2%; KRAS 1.2%; MAP2K1 1.2%; RAF1 1.2%; SHOC2 1.2%, corresponding to 50% of positivity in total NS population. The genotype-phenotype analysis showed statistically significant differences in craniofacial dysmorphisms (p = 0.005) and pulmonary valve stenosis (PS) (p < 0.001) frequencies between patients harbouring a pathogenic variant and patients without pathogenic variant in any of the tested genes. Patients with at least a pathogenic variant had 6.71 times greater odds to develop PS compared to pathogenic variant-negative patients (OR = 6.71, 95%; CI = (2.61, 17.27)). PTPN11 positive patients showed higher frequency of epicanthal folds (p = 0.004), ptosis (p = 0.001) and coarseness (p = 0.001) and lower frequency of neurological findings (p = 0.006), compared to patients carrying pathogenic variants in other genes. CONCLUSION: Craniofacial dysmorphism and PS prevail among pathogenic variant positive compared to pathogenic variant negative NS and NS-like patients while neurological defects are less common in PTPN11-affected NS patients compared to patients harbouring pathogenic variants in other genes. The significant prevalence of the Ras/MAPK pathogenic variants (17.4%), other than PTPN11, in Greek NS patients, highlights the necessity of a wider spectrum of molecular diagnosis. WHAT IS KNOWN: • Noonan syndrome (NS) has been associated with pathogenic variants in molecules-components of the Ras/MAPK pathway. • Clinical and genetic description of NS patients worldwide helps establishing personalized monitoring. WHAT IS NEW: • NS and NS-like mutational rate in Greece reaches 50% with pathogenic variants identified mostly in PTPN11 (32.5%), RIT1 (6%) and SOS1 (4.7%) genes. • The risk for pulmonary stenosis increases 6.71-fold in NS patients with a pathogenic variant compared to patients without genetic alterations.

Connecting high-throughput biodiversity inventories: Opportunities for a site-based genomic framework for global integration and synthesis.

High-throughput sequencing (HTS) is increasingly being used for the characterization and monitoring of biodiversity. If applied in a structured way, across broad geographical scales, it offers the potential for a much deeper understanding of global biodiversity through the integration of massive quantities of molecular inventory data generated independently at local, regional and global scales. The universality, reliability and efficiency of HTS data can potentially facilitate the seamless linking of data among species assemblages from different sites, at different hierarchical levels of diversity, for any taxonomic group and regardless of prior taxonomic knowledge. However, collective international efforts are required to optimally exploit the potential of site-based HTS data for global integration and synthesis, efforts that at present are limited to the microbial domain. To contribute to the development of an analogous strategy for the nonmicrobial terrestrial domain, an international symposium entitled "Next Generation Biodiversity Monitoring" was held in November 2019 in Nicosia (Cyprus). The symposium brought together evolutionary geneticists, ecologists and biodiversity scientists involved in diverse regional and global initiatives using HTS as a core tool for biodiversity assessment. In this review, we summarize the consensus that emerged from the 3-day symposium. We converged on the opinion that an effective terrestrial Genomic Observatories network for global biodiversity integration and synthesis should be spatially led and strategically united under the umbrella of the metabarcoding approach. Subsequently, we outline an HTS-based strategy to collectively build an integrative framework for site-based biodiversity data generation.

Glutamine synthetase regulation by dexamethasone, RU486, and compound A in astrocytes derived from aged mouse cerebral hemispheres is mediated via glucocorticoid receptor.

Glucocorticoids (GCs) regulate astrocyte function, while glutamine synthetase (GS), an enzyme highly expressed in astrocytes, is one of the most remarkable GCs-induced genes. GCs mediate their effects through their cognate glucocorticoid receptor (GRα and GRß isoforms); however, the mechanism via which these isoforms regulate GS activity in astrocytes remains unknown. We used dexamethasone (DEX), a classical GRα/GRß agonist, RU486, which is a specific GRß ligand, and Compound A, a known "dissociated" ligand, to delineate the mechanism via which GR modulates GS activity. Aged Mouse Cerebral Hemisphere astrocytes were treated with DEX (1 µM), RU486 (1 nM-1 µM) or compound A (10 µM), alone or in combination with DEX. GS activity and expression, GR isoforms (mRNA and protein levels), and GRα subcellular trafficking were measured. DEX increased GS activity in parallel with GRα nuclear translocation. RU486 increased GS activity in absence of GRα nuclear translocation implicating thus a role of GRß-mediated mechanism compound A had no effect on GS activity implicating a GRα-GRE-mediated mechanism. None of the compounds affected whole-cell GRα protein content. DEX reduced GRα and GRß mRNA levels, while RU486 increased GRß gene expression. We provide evidence that GS activity, in astrocytes, is regulated via GRα- and GRß-mediated pathways with important implications in pathological conditions in which astrocytes are involved.

Genomic footprints of an old affair: Single nucleotide polymorphism data reveal historical hybridization and the subsequent evolution of reproductive barriers in two recently diverged grasshoppers with partly overlapping distributions.

Secondary contact in close relatives can result in hybridization and the admixture of previously isolated gene pools. However, after an initial period of hybridization, reproductive isolation can evolve through different processes and lead to the interruption of gene flow and the completion of the speciation process. Omocestus minutissimus and O. uhagonii are two closely related grasshoppers with partially overlapping distributions in the Central System mountains of the Iberian Peninsula. To analyse spatial patterns of historical and/or contemporary hybridization between these two taxa and understand how species boundaries are maintained in the region of secondary contact, we sampled sympatric and allopatric populations of the two species and obtained genome-wide single nucleotide polymorphism data using a restriction site-associated DNA sequencing approach. We used Bayesian clustering analyses to test the hypothesis of contemporary hybridization in sympatric populations and employed a suite of phylogenomic approaches and a coalescent-based simulation framework to evaluate alternative hypothetical scenarios of interspecific gene flow. Our analyses rejected the hypothesis of contemporary hybridization but revealed past introgression in the area where the distributions of the two species overlap. Overall, these results point to a scenario of historical gene flow after secondary contact followed by the evolution of reproductive isolation that currently prevents hybridization among sympatric populations.

ß-Amyloid and mitochondrial-derived peptide-c are additive predictors of adverse outcome to high-on-treatment platelet reactivity in type 2 diabetics with revascularized coronary artery disease.

BACKGROUND AND AIMS: Increased ß-amyloid and decreased mitochondrial-derived peptide (MOTS-c), are reported in diabetes. We investigated their additive value to high on-clopidogrel platelet reactivity (HPR) for adverse outcome in type 2 diabetics after recent revascularization. PATIENTS AND METHODS: In 121 type II diabetics, treated with clopidogrel and aspirin, (93 males, mean age 67.2 years) we measured: (a) maximum platelet aggregation to adenosine diphosphate (ADP) by light transmission aggregometry (LTAmax), (b) malondialdehyde (MDA), as oxidative stress marker, (c) MOTS-c, (d) ß-amyloid blood levels. Cardiac death and acute coronary syndromes (MACE) were recorded during 2 years of follow-up. RESULTS: Out of 121 patients, 32 showed HPR (LTAmax > 48%,). At baseline, HPR was associated with ß-amyloid > 51 pg/ml (p = 0.006) after adjusting clinical variables, HbA1c, MOTS-c, MDA and medication. During follow-up, 22 patients suffered a MACE. HPR, ß-amyloid > 51 pg/ml and MOTS-c < 167 ng/ml were predictors of MACE (relative risk 3.1, 3.5 and 3.8 respectively, p < 0.05) after adjusting for confounders and medication. There was significant interaction between HPR and ß-amyloid or MOTS-c for the prediction of MACE (p < 0.05). Patients with HPR and ß-amyloid > 51 mg/dl or HPR and MOTS-c concentration < 167 ng/ml had a fourfold higher risk for MACE than patients without these predictors (relative risk 4.694 and 4.447 respectively p < 0.01). The above results were confirmed in an external validation cohort of 90 patients with diabetes and CAD. CONCLUSIONS: Increased ß-amyloid or low MOTS-c are additive predictors to high on-clopidogrel platelet reactivity for adverse outcome in diabetics with CAD during 2-years follow-up. Clinical Trial Registration-URL: https://www.clinicaltrials.gov. Unique identifier: NCT04027712.

Genomic data reveal deep genetic structure but no support for current taxonomic designation in a grasshopper species complex.

Taxonomy has traditionally relied on morphological and ecological traits to interpret and classify biological diversity. Over the last decade, technological advances and conceptual developments in the field of molecular ecology and systematics have eased the generation of genomic data and changed the paradigm of biodiversity analysis. Here we illustrate how traditional taxonomy has led to species designations that are supported neither by high throughput sequencing data nor by the quantitative integration of genomic information with other sources of evidence. Specifically, we focus on Omocestus antigai and Omocestus navasi, two montane grasshoppers from the Pyrenean region that were originally described based on quantitative phenotypic differences and distinct habitat associations (alpine vs. Mediterranean-montane habitats). To validate current taxonomic designations, test species boundaries, and understand the factors that have contributed to genetic divergence, we obtained phenotypic (geometric morphometrics) and genome-wide SNP data (ddRADSeq) from populations covering the entire known distribution of the two taxa. Coalescent-based phylogenetic reconstructions, integrative Bayesian model-based species delimitation, and landscape genetic analyses revealed that populations assigned to the two taxa show a spatial distribution of genetic variation that do not match with current taxonomic designations and is incompatible with ecological/environmental speciation. Our results support little phenotypic variation among populations and a marked genetic structure that is mostly explained by geographic distances and limited population connectivity across the abrupt landscapes characterizing the study region. Overall, this study highlights the importance of integrative approaches to identify taxonomic units and elucidate the evolutionary history of species.

Osteoporosis-pseudoglioma syndrome: clinical, genetic, and treatment-response study of 10 new cases in Greece.

Osteoporosis-pseudoglioma syndrome (OPPG) is a rare autosomal-recessive disorder, characterized by severe osteoporosis and early-onset blindness. Loss of function mutations in the gene encoding low-density lipoprotein receptor-related protein 5 (LRP5) have been established as the genetic defect of the disease. We report the clinical and genetic evaluation of ten OPPG cases in eight related nuclear families and their close relatives. Bone mineral density (BMD) in OPPG patients was assessed by dual-energy X-ray absorptiometry (DXA). Genotyping of LRP5 gene and targeted detection of index mutation were performed by DNA direct sequencing. Four patients were introduced to bisphosphonates. Mutational screening of LRP5 gene revealed the c.2409_2503+79del deletion in homozygous state, expected to result in a truncated protein. Among 44 members of the pedigree, 10 (22%) were identified homozygous and 34 (59%) heterozygous for this mutation. All patients had congenital blindness and 7 of them had also impaired bone mineral density. Four of them received bisphosphonates and responded with decreased bone pain and improvement in BMD; however, 3 patients presented with one fracture during treatment.Conclusion: The current study presents the molecular and clinical profiles of 10 new OPPG cases, being part of an extended pedigree. Patients who received bisphosphonate treatment responded well with increase in their BMD, though fractures occurred during therapy. What is known: • OPPG syndrome is a rare genetic disorder characterized by congenital blindness and juvenile osteoporosis. • Loss of function mutations in the gene encoding low-density lipoprotein receptor-related protein 5 (LRP5) is the genetic defect of the disease. What is new: • Genetic and clinical phenotype of 10 new OPPG patients. • The ten new OPPG patients presented with phenotypical variability in osseous manifestations.

Toward a paradigm shift in comparative phylogeography driven by trait-based hypotheses.

For three decades, comparative phylogeography has conceptually and methodologically relied on the concordance criterion for providing insights into the historical/biogeographic processes driving population genetic structure and divergence. Here we discuss how this emphasis, and the corresponding lack of methods for extracting information about biotic/intrinsic contributions to patterns of genetic variation, may bias our general understanding of the factors driving genetic structure. Specifically, this emphasis has promoted a tendency to attribute discordant phylogeographic patterns to the idiosyncracies of history, as well as an adherence to generic null expectations of concordance with reduced predictive power. We advocate that it is time for a paradigm shift in comparative phylogeography, especially given the limited utility of the concordance criterion as genomic data provide ever-increasing levels of resolution. Instead of adhering to the concordance-discordance dichotomy, comparative phylogeography needs to emphasize the contribution of taxon-specific traits that will determine whether concordance is a meaningful criterion for evaluating hypotheses or may predict discordant phylogeographic structure. Through reference to some case studies we illustrate how refined hypotheses based on taxon-specific traits can provide improved predictive frameworks to forecast species responses to climatic change or biogeographic barriers while gaining unique insights about the taxa themselves and their interactions with their environment. We outline a potential avenue toward a synthetic comparative phylogeographic paradigm that includes addressing some important conceptual and methodological challenges related to study design and application of model-based approaches for evaluating support of trait-based hypotheses under the proposed paradigm.

Adherence to the Mediterranean diet and inflammatory markers in children with asthma.

INTRODUCTION: There is accumulated evidence supporting a beneficial role of Mediterranean diet (MD) in the control of asthma symptoms. The aim of this study was to investigate the relationships between adherence to MD and serum levels of certain cytokines namely, interleukin (IL)-4, and IL-17 known to have a pathogenetic role in the airway changes associated with asthma. METHODS: We measured serum IL-4, IL-33, and IL-17, in 44 asthmatic and 26 healthy children, 5-15 years old. Their adherence to MD was estimated with the Mediterranean Diet Quality Index for children and adolescents (KIDMED) score. RESULTS: KIDMED score did not differ between the two groups (P=0.59) and was not correlated with any of the three measured cytokines. However, when the analysis was restricted only to asthmatic children, the KIDMED score was correlated with IL-4, IL-33, and IL-17 (Beta: -0.56, P=0.007; Beta: 0.57, P=0.010; Beta: -0.62, P=0.017, respectively). CONCLUSION: Our results indicate that MD can modulate the production of some of the main inflammatory mediators of asthma, in asthmatic children.

Inhibition Activity of Compounds and Bacteriophages against Flavobacterium psychrophilum Biofilms In Vitro.

Flavobacterium psychrophilum produces biofilms under laboratory conditions, and it has been inconclusively suggested that F. psychrophilum biofilms can be a potential reservoir for transmission of the pathogen to a fish population under fish farming conditions. Therefore, there is a need for anti-biofilm compounds. The main aim of this study was to determine the anti-biofilm properties of certain compounds and bacteriophages on F. psychrophilum biofilms under static conditions using a standard 96-well microtiter plate biofilm assay in vitro. Eight compounds (A-type proanthocyanidins, D-leucine, EDTA, emodin, fucoidan, L-alliin, parthenolide, and 2-aminoimidazole) at three sub-minimum inhibitory concentrations (sub-MICs), four bacteriophages (Fpv-3, Fpv-9, Fpv-10, and Fpv-21), and a phage combination (Fpv-9 + Fpv-10) were tested for inhibition of biofilm formation and reduction of the biomass of mature biofilms formed by two smooth isolates (P7-9/10 and P1-10B/10) and two rough isolates (P7-9/2R/10 and P1-10B/2R/10) of F. psychrophilum. The crystal violet staining method was used to stain the biofilms. Most of the compounds at sub-MICs inhibited the biofilm formation of mainly smooth isolates, attaining up to 80% inhibition. Additionally, the same reduction trend was also observed for 2-aminoimidazole, emodin, parthenolide, and D-leucine on the biomass of mature biofilms in a concentration-dependent manner. The anti-biofilm properties of the compounds are believed to lie in their ability to disturb the cellular interactions during biofilm formation and probably to cause cell dispersal in already formed biofilms. Lytic bacteriophages efficiently inhibited biofilm formation of F. psychrophilum, while they partially reduced the biomass of mature biofilms. However, the phage combination (Fpv-9 + Fpv-10) showed a successful reduction in the biomass of F. psychrophilum mature biofilms. We conclude that inhibiting compounds together with bacteriophages may supplement the use of disinfectants against bacterial biofilms (e.g., F. psychrophilum biofilms), leading to a reduced occurrence of bacterial coldwater disease outbreaks at fish farms.

Wiskott-Aldrich Syndrome Misdiagnosed as Immune Thrombocytopenic Purpura: A Case Report.

Wiskott-Aldrich syndrome (WAS) is a rare X-linked immunodeficiency characterized by various clinical phenotypes. We report the case of a 3-year-old immigrant boy presenting with persistent infant-onset thrombocytopenia treated for refractory immune thrombocytopenic purpura. Sequence analysis confirmed the diagnosis of WAS. The patient responded neither to IV infusions of immunoglobulin (Ig) nor a thrombopoietin receptor agonist and is currently planned for stem cell transplantation. Raised awareness is thus vital of this potentially misdiagnosed and lethal disorder. The diagnosis of WAS should be considered in all males with infant-onset immune thrombocytopenic purpura-like features, especially, if mean platelet volume is decreased (<7 fL) and good increment to platelet transfusions are evident.

Novel NPC1 mutations with different segregation in two related Greek patients with Niemann-Pick type C disease: molecular study in the extended pedigree and clinical correlations.

BACKGROUND: Niemann-Pick type C disease (NPC) is an autosomal recessive, neurovisceral, lysosomal storage disorder with protean and progressive clinical manifestations, resulting from mutations in either of the two genes, NPC1 (~95% of families) and NPC2. Contrary to other populations, published evidence regarding NPC disease in Greece is sparse. METHODS: The study population consisted of two Greek NPC patients and their extended pedigree. Patients' clinical, biochemical, molecular profiles and the possible correlations are presented. Genotyping was performed by direct sequencing. Mutations' origin was investigated through selected exonic NPC1 polymorphisms encountered more frequently in a group of 37 Greek patients with clinical suspicion of NPC disease and in a group of 90 healthy Greek individuals, by the use of Haplore software. RESULTS: Two novel NPC1 mutations, [IVS23 + 3insT (c.3591 + 3insT) and p. K1057R (c.3170A > C)] were identified and each mutation was associated with a specific haplotype. One of the patients was entered to early treatment with miglustat and has presented no overt neurological impairment after 11.5 years. CONCLUSIONS: The splicing mutation IVS23 + 3insT was associated in homozygocity with a severe biochemical and clinical phenotype. A possible founder effect for this mutation was demonstrated in the Greek Island, as well as a different origin for each novel mutation. Longitudinal follow-up may contribute to clarify the possible effect of early miglustat therapy on the patient compound heterozygous for the two novel mutations.

Glacial refugia, recolonization patterns and diversification forces in Alpine-endemic Megabunus harvestmen.

The Pleistocene climatic fluctuations had a huge impact on all life forms, and various hypotheses regarding the survival of organisms during glacial periods have been postulated. In the European Alps, evidence has been found in support of refugia outside the ice shield (massifs de refuge) acting as sources for postglacial recolonization of inner-Alpine areas. In contrast, evidence for survival on nunataks, ice-free areas above the glacier, remains scarce. Here, we combine multivariate genetic analyses with ecological niche models (ENMs) through multiple timescales to elucidate the history of Alpine Megabunus harvestmen throughout the ice ages, a genus that comprises eight high-altitude endemics. ENMs suggest two types of refugia throughout the last glacial maximum, inner-Alpine survival on nunataks for four species and peripheral refugia for further four species. In some geographic regions, the patterns of genetic variation are consistent with long-distance dispersal out of massifs de refuge, repeatedly coupled with geographic parthenogenesis. In other regions, long-term persistence in nunataks may dominate the patterns of genetic divergence. Overall, our results suggest that glacial cycles contributed to allopatric diversification in Alpine Megabunus, both within and at the margins of the ice shield. These findings exemplify the power of ENM projections coupled with genetic analyses to identify hypotheses about the position and the number of glacial refugia and thus to evaluate the role of Pleistocene glaciations in driving species-specific responses of recolonization or persistence that may have contributed to observed patterns of biodiversity.