Multigene phylogenetic data place monoraphid diatoms Schizostauron and Astartiella along with other fistula-bearing genera in the Stauroneidaceae1

Presented here are new insights into the marine monoraphid diatom genera Schizostauron and Astartiella, based on molecular and morphological data, including descriptions of new species. Although no unambiguous morphological synapomorphies between the two genera are currently recognized, they are closely related by DNA sequence data. Heterovalvate frustules of Schizostauron are characterized by a bifid stauros on the raphe-bearing valve and intricate areolate occlusions on the sternum valve. In Astartiella, the raphe-bearing valve is characterized by a process resembling a fistula by morphology, while the sternum valve presents a particular striation pattern. Observations by light and electron microscopy were made, along with a molecular phylogenetic analysis using a three-gene (SSU, rbcL, and psbC) concatenated dataset. Three new Schizostauron species are described (S. kajotkei, S. rawaii, S. papilliareae), and two new combinations proposed (S. citronella and S. trachyderma) for species that were previously included either in Achnanthes and Cocconeis, respectively. Likewise, six new species of Astartiella (A. almalikii, A. bornmanii, A. chunlianlii, A. marksii, A. persica, and A. wangii) are described. Molecular results exclude Schizostauron and Astartiella from three clades of exclusively monoraphid diatoms, the Achnanthaceae, Cocconeidaceae, and Achnanthidiaceae, instead placing them in the Stauroneidaceae. Morphological features of Schizostauron and Astartiella, such as the stauros, fistula, and coaxial internal proximal raphe endings, are found in other genera in this clade, whereas the only common feature with monoraphid diatoms as whole group is the heterovalvy of frustules.

Reducing Efficiency of Fucoxanthin in Diatom Mediated Biofabrication of Gold Nanoparticles

In the present investigation, fucoxanthin—one of the major pigments in diatoms—has been extracted from Nanofrustulum shiloi SZCZM1342, and its reducing efficiency in the biogenesis of gold nanoparticles (GNPs) was checked. Fucoxanthin extracted from golden-brown cells of N. shiloi was compared to the healthy, growing biomass of N. shiloi and standard fucoxanthin after separate exposure to 25 mg L⁻¹ aqueous hydrogen tetrachloroaurate solutions at room temperature. Isolated and standard fucoxanthin were found to be able to reduce gold ions within 12 h whereas, the whole biomass turned pink in color after 72 h of reaction. The synthesized particles were characterized by UV-vis spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). UV–vis spectroscopy of purple-colored suspensions showed the absorption band at approximately 520–545 nm, indicating a strong positive signal for GNP synthesis. The SEM study revealed the deposition of GNPs on siliceous frustules of metal-treated diatom cells. The TEM analysis confirmed the GNPs synthesized by whole biomass are triangular, spherical and hexagonal in nature, whereas the particles produced by extracted and standard fucoxanthin are all spherical in nature. This study demonstrates the involvement of fucoxanthin in the reduction of gold ions and subsequent production of gold nanospheres.

Extreme Enlargement of the Inverted Repeat Region in the Plastid Genomes of Diatoms from the Genus Climaconeis

We sequenced the plastid genomes of three diatoms from the genus Climaconeis, including two strains formerly designated as Climaconeis scalaris. At 208,097 and 216,580 bp, the plastid genomes of the latter strains are the largest ever sequenced among diatoms and their increased size is explained by the massive expansion of the inverted repeat region. Important rearrangements of gene order were identified among the two populations of Climaconeis cf. scalaris. The other sequenced Climaconeis chloroplast genome is 1.5 times smaller compared with those of the Climaconeis cf. scalaris strains and it features an usual quadripartite structure. The extensive structural changes reported here for the genus Climaconeis are compared with those previously observed for other algae and plants displaying large plastid genomes.

Diatom Genus Hyalosira (Rhabdonematales emend.) and Resolution of its Polyphyly in Grammatophoraceae and Rhabdonemataceae with a New Genus, Placosira, and Five New Hyalosira Species

Hyalosira gene sequences are divided into two clades within different families. We examined authentic material of Hyalosira (isotype material of H. obtusangula, synonymous with H. delicatula) and voucher specimens of published sequences, and pooled our observations of Hyalosira-like taxa from benthic and epizoic habitats in several parts of the globe. The two molecular clades corresponded to two morphological groups, with Hyalosira obtusangula associated with Grammatophoraceae. We emend the description and provide lectotypification for Hyalosira and propose Placosira to encompass the taxa in the other clade, associated with Rhabdonemataceae. We propose that Hyalosira has uniseriate to triseriate striae, sometimes different on valve face and mantle. Copulae in most species had shallow septa, though in one they were moderately deep. All species had girdle bands bearing two rows of areolae separated by a midrib. We name five new species of Hyalosira. Morphologies of taxa in the Placosira clade were superficially similar to Hyalosira but differed in having areolae with ricae, a single row of areolae on the girdle bands, and tubular rimoportulae on the valve-face-mantle junction. Hyalosira hustedtiana Patrick should revert to its original position in Striatella until the appropriate genus can be determined. We emend Rhabdonematales to encompass Rhabdonemataceae, Grammatophoraceae and Tabellariaceae.

Haslea silbo, A Novel Cosmopolitan Species of Blue Diatoms

Specimens of a new species of blue diatoms from the genus Haslea Simonsen were discovered in geographically distant sampling sites, first in the Canary Archipelago, then North Carolina, Gulf of Naples, the Croatian South Adriatic Sea, and Turkish coast of the Eastern Mediterranean Sea. An exhaustive characterization of these specimens, using a combined morphological and genomic approach led to the conclusion that they belong to a single new to science cosmopolitan species, Haslea silbo sp. nov. A preliminary characterization of its blue pigment shows similarities to marennine produced by Haslea ostrearia, as evidenced by UV-visible spectrophotometry and Raman spectrometry. Life cycle stages including auxosporulation were also observed, providing data on the cardinal points of this species. For the two most geographically distant populations (North Carolina and East Mediterranean), complete mitochondrial and plastid genomes were sequenced. The mitogenomes of both strains share a rare atp6 pseudogene, but the number, nature, and positions of the group II introns inside its cox1 gene differ between the two populations. There are also two pairs of genes fused in single ORFs. The plastid genomes are characterized by large regions of recombination with plasmid DNA, which are in both cases located between the ycf35 and psbA genes, but whose content differs between the strains. The two sequenced strains hosts three plasmids coding for putative serine recombinase protein whose sequences are compared, and four out of six of these plasmids were highly conserved.

Three new Luticola D.G.Mann (Bacillariophyta) species from Rapa Nui (Easter Island) found in terrestrial diatom assemblages dominated by widely distributed taxa

Background

Rapa Nui (Easter Island = Isla de Pasqua) is of volcanic origin, best known for about 900 man-made stone statues known as moai. It is one of the most isolated inhabited islands on Earth and studies on the diatoms of Rapa Nui are very few.

Methods

Light (LM) and electron microscopic (SEM) observations of a single sample collected from Rapa Nui are presented. The samples (mix of soil and organic detritus) were collected from ground of cave entrance.

Results

The samples were characterized by low diatom diversity and strongly dominated by terrestrial (soil) forms. Among the taxa present in the material studied were cosmopolitan forms of the genera Humidophila, Nitzschia, Angusticopula, Orthoseira, Tryblionella and Luticola. Whereas most of taxa of the enumerated genera were identifiable, only one among four Luticola species distinguished in the samples studied was identified. This taxon was L. ectorii, a cosmopolitan species known previously from South America (Brazil) and Asia (China). The three remaining species could not be assigned to any established species. Therefore, based on external and internal morphological features from light and scanning electron microscopic analysis, we describe here three species new to science, including: L. georgzizkae, L. rapanuiensis and L. moaiorum. All three taxa new to science are compared to established Luticola species and their significance for the global distribution of the genus is discussed.

Metadata standards and practical guidelines for specimen and DNA curation when building barcode reference libraries for aquatic life

DNA barcoding and metabarcoding is increasingly used to effectively and precisely assess and monitor biodiversity in aquatic ecosystems. As these methods rely on data availability and quality of barcode reference libraries, it is important to develop and follow best practices to ensure optimal quality and traceability of the metadata associated with the reference barcodes used for identification. Sufficient metadata, as well as vouchers, corresponding to each reference barcode must be available to ensure reliable barcode library curation and, thereby, provide trustworthy baselines for downstream molecular species identification. This document (1) specifies the data and metadata required to ensure the relevance, the accessibility and traceability of DNA barcodes and (2) specifies the recommendations for DNA harvesting and for the storage of both voucher specimens/samples and barcode data.

A gene-rich and compact chloroplast genome of the green alga Nephroselmis pyriformis (N.Carter) Ettl 1982 from the shores of Mersin (Eastern Mediterranean Sea)

We report the complete chloroplast genome of the MED1 strain of Nephroselmis pyriformis from the Eastern Mediterranean Sea. At 111,026 bp, this genome is smaller and more compact than those of Nephroselmis olivacea and Nephroselmis astigmatica, and in contrast to the latter taxa, its inverted repeat contains no complete protein-coding genes. It encodes 3 rRNAs, 33 tRNAs and 94 proteins. Maximum likelihood analysis of a concatenated set of chloroplast genes from green algae belonging to deep-diverging lineages positioned the three Nephroselmis species in a strongly supported clade in which N. pyriformis is sister to N. astigmatica.

trans-3-Methylglutaconyl CoA isomerization-dependent protein acylation

3-methylglutaconic (3MGC) aciduria is associated with a growing number of discrete inborn errors of metabolism. Herein, an antibody-based approach to detection/quantitation of 3MGC acid has been pursued. When trans-3MGC acid conjugated keyhole limpet hemocyanin (KLH) was inoculated into rabbits a strong immune response was elicited. Western blot analysis provided evidence that immune serum, but not pre-immune serum, recognized 3MGC-conjugated bovine serum albumin (BSA). In competition ELISAs using isolated immune IgG, the limit of detection for free trans-3MGC acid was compared to that for cis-3MGC acid and four structurally related short-chain dicarboxylic acids. Surprisingly, cis-3MGC acid yielded a much lower limit of detection (∼0.1 mg/ml) than trans-3MGC acid (∼1.0 mg/ml) while all other dicarboxylic acids tested were poor competitors. The data suggest trans-3MGC- isomerized during, or after, conjugation to KLH such that the immunogen was actually comprised of KLH harboring a mixture of cis- and trans-3MGC haptens. To investigate this unexpected isomerization reaction, trans-3MGC CoA was prepared and incubated at 37 °C in the presence of BSA. Evidence was obtained that non-enzymatic isomerization of trans-3MGC CoA to cis-3MGC CoA precedes intramolecular catalysis to form cis-3MGC anhydride plus CoASH. Anhydride-dependent acylation of BSA generated 3MGCylated BSA, as detected by anti-3MGC immunoblot. The results presented provide an explanation for the unanticipated detection of 3MGCylated proteins in a murine model of primary 3MGC aciduria. Furthermore, non-enzymatic hydrolysis of cis-3MGC anhydride represents a potential source of cis-3MGC acid found in urine of subjects with 3MGC aciduria.

Calcified mitro-aortic continuity and mitral regurgitation in patients undergoing transcatheter aortic valve replacement

Introduction

Calcified aortic stenosis (AS) and mitral annular calcification (MAC) have similar etiology and pathophysiological mechanisms. Half of all patients undergoing transcatheter aortic valve implantation (TAVI) have MAC. Several studies assessed the role of mitral regurgitation (MR) following TAVI but only few examined influence of MAC on its changes after TAVI. MAC frequently coexists with the calcification of mitro-aortic continuity (CMAC).

Purpose

Presence of CMAC may influence the results of TAVI, especially in the case of deeper implantation, protruding to let ventricular outflow tract (LVOT). In the present study we aimed at qualitative and semi-quantitative analysis of calcifications of the mitral complex – MAC and CMAC in multi-slice computed tomography (MSCT) in patients qualified to TAVI, in order to assess their impact on the occurrence and dynamics of MR following aortic valve implantation.

Methods

MAC was assessed quantitatively (Calcium Score) and semi-quantitative scale in depending on the degree of annular involvement. CMAC was evaluated in semi-quantitatively scale in depending on length of calcifications in the largest dimension. Subsequently patients were classified in a dichotomous manner as having non-severe or severe MAC and CMAC. All patients underwent transthoracic echocardiographic examinations prior to the procedure and after TAVI. Changes of MR severity following TAVI were defined as no change, improvement or worsening by at least one degree.

Results

The study group consisted of 94 patients. Fifty six (59.6%) out of 94 patients had MAC and 21 patients (22.3%) had severe MAC. Patients with MAC had higher mean aortic gradients (54.07±13,62 mmHg vs 46.79±14.42 mmHg, p=0.02) and smaller left ventricular diastolic diameter (46.09±6.86 mm vs 51.19±8.42 mm, p=0.002). Almost half of the patients - 46 (48.9%) had CMAC and 12 patients (12.8%) had severe CMAC. Patients with CMAC had higher Calcium Score Aortic Valve (3773.67±1734.02 Hounsfield Units (HU) vs 2875.1±1352.76 HU, p=0.006) and smaller AVA (0.59±0.16 cm2 vs 0.66±0.20 cm2, p=0.052). Before TAVI 35.1% of patients had more than mild MR. MR improved by at least one grade following TAVI in 17 (18.1%) patients and worsened by at least one grade in 7 (7.5%) patients. In multivariable logistic regression analysis MR worsening was associated with higher CMAC [OR 1.092, 95% CI: 1.006–1.185, p=0.035].

Conclusions

The study demonstrated CMAC is prevalent in patients undergoing TAVI. CMAC was associated with MR worsening. This is a novel finding, which may be particular importance in patients with severe AS and coexisting MR in whom arguments for and against surgical repair of concomitant mitral insufficiency are considered, as opposed to isolated aortic valve procedure.

Funding Acknowledgement

Type of funding source: None

Infarct-related artery and long-term mortality following recurrent ST-elevation myocardial infarction; insights from a Polish nationwide registry

Background

Recurrent ST-elevation myocardial infarction (rSTEMI) occurs either as an acute thrombotic event in the same (target-vessel, TV-STEMI) or different vessel (non-target, nonTV-STEMI) compared with the first infarction. Little is known about the frequency of rSTEMI in the era of primary percutaneous coronary intervention (PCI) and about the impact of the infarct-related artery (IRA) on long-term prognosis.

Purpose

We hypothesized that long-term mortality after rSTEMI varies according to IRA (either same or different compared with first STEMI).

Methods

We retrospectively analysed data from the Polish Registry of Acute Coronary Syndromes (PL-ACS) and identified survivors of first STEMI treated with PCI who experienced rSTEMI and were discharged home. We divided rSTEMI into TV-STEMI and nonTV-STEMI group. We compared baseline clinical, angiographic and procedural characteristics and utilized propensity score matching to adjust for baseline differences. 1-, 3- and 5-year all-cause mortality was obtained from the Polish National Health Fund. Categorical variables were presented as counts and percentages and compared using Chi2 test. Continuous variables were presented as medians and interquartile ranges and compared using Mann-Whitney test. The registry was approved by local Ethics Committee and meets the conditions of the Declaration of Helsinki

Results

Between January 2003 and August 2019 a total of 3517 patients (mean age 62.9 years, 75% male) had rSTEMI, of whom 1941 (55%) had TV- and 1576 (45%) had nonTV-STEMI after 615 (77, 1683) days since first infarction (Figure 1). Patients with nonTV-STEMI had higher BMI (27.2 vs 26.8 kg/m2, p=0.03), more hypertension (76.9 vs. 73.5%, p=0.02) and atrial fibrillation (4.7 vs. 3.3%, p=0.04), but had lower left ventricular ejection fraction (43 [35,50] vs. 45 [38,50], p<0.001) compared with TV-STEMI. On coronary angiography nonTV-STEMI had more frequently TIMI flow ≥1 (44.9 vs. 28.0%, p<0.001), multivessel disease (51.8 vs. 41.1%, p=0.003), culprit lesion located in circumflex artery (15.2 vs. 4.8, p<0.001) and more frequently underwent stenting (88.4 vs. 76.1%, p<0.001) compared with TV-STEMI. There was no difference in unadjusted 1-, 3- and 5-year mortality between nonTV-STEMI and TV-STEMI group (14.9 vs. 14.7%, p=0.9; 23.4 vs. 24.2%, p=0.64 and 29.6 vs. 32.9%, p=0.1 respectively). The propensity-score matching of 825 patients with TV- and 826 patients with nonTV STEMI suppressed all baseline differences, but adjusted mortality remained similar between study groups (Figure 1).

Conclusion

While patients with recurrent nonTV-STEMI have different clinical and angiographic characteristics compared with TV-STEMI, the long-term mortality in these groups is similar.

Figure 1

Funding Acknowledgement

Type of funding source: None

Managed care improves prognosis in acute myocardial infarction survivors. Data from the MAnaged Care for Acute Myocardial Infarction Survivors (MACAMIS) Programme

Background

Mortality following acute myocardial infarction (MI) remains high despite progress in pharmacotherapy and interventional treatment. In 2017 a nation-wide system of managed care for MI survivors comprising a continuum of acute treatment of MI, staged revascularization, cardiac rehabilitation, cardiac electrotherapy and cardiac ambulatory care within one year following MI was implemented in Poland. The managed care programme (MCP) includes also the quality of care assessment based on clinical measures (e.g. cardiovascular risk factors control) as well as on the rate of minor and major cardiovascular events. The goal of the analysis was to assess the overall mortality of MI survivors participating and not participating in the MCP.

Methods

The database of survivors of acute MI discharged from hospital from October 1, 2017 to December 31, 2018 was analyzed. Patients who died within 10 days after discharge were excluded from the analysis. The primary end-point was defined as death from any cause. Propensity-Score Matching (PSM) using nearest neighbor matching was used to form comparable groups of patients participating and not participating in the MCP. The Cox proportional hazard regression analysis was used to assess the relation between MCP and the overall mortality.

Results

MCP was implemented in the first stage in 48 hospitals spread around the country (about 34% of all hospitals treating acute MI patients in Poland). Out of 87739 analyzed patients (age: 68.1±11.9 years; 55581 men and 32158 women) 34064 were hospitalized in hospitals with MCP implemented. Altogether 10404 patients (11.9% of the whole cohort; 30.5% of those hospitalized in hospitals with MCP implemented) participated in MCP. They were matched with 10404 patients not participating in the MCP. During 324.8±140.5 days of follow-up 7413 patients died. One-year mortality was lower in patients participating in the MCP both when we analyzed the whole cohort (4.4% vs. 9.5%; p<0.001) as well as when we limited the analysis to the PSM groups (4.4% vs. 6.5%; p<0.001, figure 1). MCP was related to the overall mortality in univariate (HR 0.43 [0.39–0.48]) as well as in multivariate analysis (0.64 [0.57–0.71]) in the whole cohort as well as in the PSM cohort (HR 0.63 [0.56–0.72] and 0.64 [0.56–0.72] for the univariate and multivariate analysis respectively). When we limited the analysis to hospitals in which MCP was implemented one-year mortality was 4.3% vs. 6.3% (p<0.001) whereas univariate HR was 0.51 (0.44–0.60) and multivariate HR 0.52 (0.44–0.61).

Conclusion

The implemented in Poland nation-wide system of managed care for MI survivors is related to improved survival. Therefore, the Ministry of Health plans to implement the programme in all cardiac centers in Poland.

Funding Acknowledgement

Type of funding source: None

Impact of annular and cusps calcification on occurrence of paravalvular leak after transcatheter aortic valve replacement with intra- versus supra-annular devices

Introduction

Severe annular and valve cusps calcification is frequent among patients treated with transcatheter aortic valve replacement (TAVR). Severe annular calcification increases the risk of paravalvular leak (PVL) and was associated with worse outcomes. Whether it is accompanied by an independent effect of calcifications localized on cusps and whether the impact of cusps/annular calcification depends on supra vs intra-annular valve design is unknown.

Purpose

To assess the impact of cusps/annular calcifications on occurrence of moderate PVL after successful TAVR with devices of either intra- or supra-annular design.

Methods

282 consecutive patients (80.3±7.6 yrs, 63% female) with baseline 384-slice CT scan were successfully treated with TAVR between Jul 2012 and Oct 2017, either with intra-annular or supra-annular devices. Severe annular calcification (clear protrusion) and severe cusps calcification (Rosenhek 4 score) were identified using a Syngo Via.

Results

138 (48.9%) patients were treated with intra-annular and 144 (51.15) with supra-annular devices. Whereas severe annular calcification was similar (23.9% vs 20.1%), there was more severe cusps calcification among intra-annular valves (52.9% vs 41.7%, p=0.073). Intra-annular devices were used less frequently among bicuspid aortic valves, were also of smaller diameter, less frequently deployed after pre-dilation, and less frequently post-dilated. Post-procedure mean aortic gradient tended to be higher among intra-annular devices. Moderate PVL was less frequent among intra- vs supra-annular valves (14.5% vs 34.0%, p<0.001). However, PVL occurrence was higher (30.3%) among those (33/138, 23.9%) treated with an intra-annular valve who had severe annular calcification vs 9.5% in pts treated with an intra-annular TAVR who did not have severe annular calcification (p=0.008) unlike in patients treated with a supra-annular valve who had a high frequency of PVL with or without severe annular calcium (37.9% vs 33.0%). After excluding patients with severe annular calcium (n=62, 22%), moderate PVL was similar between those with vs without severe cusp calcification whether treated with intra- or supra-annular valves (11.8% vs 7.4% and 29.3% vs 35.1%, respectively). Combined VARC-2 safety endpoints plus 2-yr mortality occurrence were lower for intra- vs supra-annular devices (30.4% vs 43.8%, p=0.026).

Conclusions

Moderate PVL after intra-annular TAVR device deployment occurs in 30% of patients with protruding annular calcification. Severe cusps calcification unaccompanied by annular calcium was not associated with PVL occurrence. Higher frequency of moderate PVL (34%) seen after supra-annular valve deployment appears to be related to other parameters rather than presence of severe annular or cusps calcification.

Funding Acknowledgement

Type of funding source: None

Ripe for reassessment: A synthesis of available molecular data for the speciose diatom family Bacillariaceae

The Bacillariaceae is a very species-rich family of raphid diatoms and includes the large and taxonomically difficult genus Nitzschia, whose species are often small-celled and finely structured and have few discrete morphological characters visible in the light microscope. The classification of Nitzschia is still mostly based on one developed in the second half of the 19th century by Grunow, who separated the genus into a series of sections largely on cell shape and symmetry, the position of the raphe, transverse extension of the fibulae, and folding of the valve. We assembled and analysed single-gene and concatenated alignments of nSSU, nLSU, rbcL, psbC and cox1 to test Grunow's and subsequent classifications and to examine selected morphological characters for their potential to help define monophyletic groups. The maximum likelihood trees were equivocal as to monophyly of the family itself but showed good support for each of eight main clades of Bacillariaceae, three of which corresponded more or less to existing genera (Hantzschia, Cylindrotheca and Bacillaria). The other five main clades and some subclades comprised groups of Nitzschia species or assemblies of Nitzschia species with other genera (Pseudo-nitzschia, Fragilariopsis, Neodenticula, Tryblionella, Psammodictyon). Relationships between most of the eight main clades were not resolved robustly but all analyses recovered Nitzschia as non-monophyletic. The Grunowian classification of Nitzschia into sections was not supported, though in some respects (e.g. treatment of sigmoid species) it is better than subsequent reclassifications. Several of the main clades and subclades are cryptic (lacking morphological synapomorphies) and homoplasy is common in both light microscopical and ultrastructural characters (to the extent that organisms initially assigned to the same species sometimes prove to belong to a different main clade). Nevertheless, some characters, including the structure of the raphe canal and girdle, seem to be sufficiently conservative evolutionarily to give a provisional estimate of relationships if molecular data are unavailable. No new formal classifications are proposed but various options are explored and research needs identified.

The Taxonomy and Diversity of Proschkinia (Bacillariophyta), A Common But Enigmatic Genus from Marine Coasts

Detailed morphological documentation is provided for established Proschkinia taxa, including the generitype, P. bulnheimii, and P. complanata, P. complanatula, P. complanatoides and P. hyalosirella, and six new species. All established taxa are characterized from original material from historical collections. The new species described in this paper (P. luticola, P. staurospeciosa, P. impar, P. modesta, P. fistulispectabilis, and P. rosowskii) were isolated from the Western Pacific (Yellow Sea coast of Korea) and the Atlantic (Scottish and Texas coasts). Thorough documentation of the frustule, valve and protoplast architecture revealed the combination of characters diagnostic of the genus Proschkinia: a single-lobed chloroplast; a broad girdle composed of U-shaped, perforated bands; the position of the conopeate raphe-sternum relative to the external and internal valve surface; and the presence of an occluded process through the valve, termed the "fistula". Seven strains of Proschkinia were grown in culture and five of these were sequenced for nuclear ribosomal SSU and plastid-encoded rbcL. Phylogenetic analysis recovered a clade of Proschkinia with Fistulifera, another fistula-bearing diatom genus, and together these were sister to a clade formed of the Stauroneidaceae; in turn, all of these were sister to a clade composed of Parlibellus and two monoraphid genera Astartiella and Schizostauron. Despite morphological similarities between Proschkinia and the Naviculaceae, these two taxa are distant in our analysis. We document the variation in the morphology of Proschkinia, including significant variability in the fistula, suggesting that fistula ultrastructure might be one of the key features for species identification within the genus.

Biodiversity of carapace epibiont diatoms in loggerhead sea turtles (Caretta caretta Linnaeus 1758) in the Aegean Sea Turkish coast

Background

The Aegean Sea coast of Turkey hosts one of the most important nesting grounds for loggerhead sea turtles (Caretta caretta) in the Mediterranean Sea. Previous studies have revealed that the sea turtle carapace provides favourable conditions for various epibiontic organisms. Epibionts occurring on the carapace have been examined from different locations in the oceans.

Methods

This is the first time such a high number (39) of samples collected from nesting turtles during such a long time period (extending from 2011 to 2018) has been used for the study of the diatom component of the microbiome on the turtle carapaces. A total of 33 samples were investigated in terms of light microscopy (LM) and scanning electron microscopy (SEM). Six unprocessed biofilm fragments were subject to SEM observations.

Results

A total of 457 epizoic diatom taxa belonging to 86 genera were identified. Epizoic forms, e.g., Achnanthes spp., Chelonicola spp. or Tripterion spp. (also identified by SEM observations of the undisturbed pieces of the microbiome) dominated in terms of relative abundance, but the highest numbers of taxa were ubiquitously represented by Navicula (79), Nitzschia (45), Amphora (40), Cocconeis (32), Diploneis (25) and Mastogloia (23). Navicula perminuta and Delphineis australis were the most frequent taxa, present in 65% of the samples, both with an average relative abundance of 10%. The results of our study revealed that diatoms are an essential component of the loggerhead sea turtles’ microbiome, in terms of high biodiversity and abundance. Although strict epibionts provide a signature of the turtle microbiome, the carapace as a solid substrate attracts numerous benthic diatom species which are considered opportunistic forms and can be found in the surrounding benthic habitats of the vast ocean littoral space.

"Outsourcing" Diatoms in Fabrication of Metal-Doped 3D Biosilica

Diatoms have an ability that is unique among the unicellular photoautotrophic organisms to synthesize an intricately ornamented siliceous (biosilica) exoskeleton with an ordered, hierarchical, three-dimensional structure on a micro- to nanoscale. The unique morphological, structural, mechanical, transport, photonic, and optoelectronic properties of diatomaceous biosilica make it a desirable material for modern technologies. This review presents a summary and discussion of published research on the metabolic insertion of chemical elements with specific functional activity into diatomaceous biosilica. Included in the review is research on innovation in methods of synthesis of a new generation of functional siliceous materials, where the synthesis process is "outsourced" to intelligent microorganisms, referred to here as microtechnologists, by providing them with appropriate conditions and reagents.

Morphology, phylogeny, and molecular dating in Plagiogrammaceae family focused on Plagiogramma-Dimeregramma complex (Urneidophycidae, Bacillariophyceae)

Although previous phylogenetic analyses suggested that the araphid diatom family Plagiogrammaceae is monophyletic, there is still not a clear understanding of relationships among the genera, and the taxonomy of several genera--Dimeregramma and Plagiogramma--remains questionable in light of paraphyly for both genera using molecular and morphological data. We have expanded the available DNA for molecular work for dozens of plagiogrammacean clones and analyzed 29 morphological characters from plagiogrammarian taxa and closely related genera, to increase understanding of the evolutionary history and systematics of the family and re-evaluate the current taxonomical classification of plagiogrammacean genera. The addition of more taxa and more data confirm the results from previous molecular phylogenies: most plagiogrammacean genera are monophyletic, except for Dimeregramma and Plagiogramma. Interestingly, the morphological analysis resolves only Talaroneis and Glyphodesmis as monophyletic. Given these results, we feel there is limited support for retaining Dimeregramma and Plagiogramma as distinct genera, and formally propose amending Plagiogramma and transferring six Dimeregramma species. As the Plagiogrammaceae is also one of the first-diverging clades of pennate diatoms, we also used these molecular data to estimate the age of the family, based on multiple calibration points derived from fossil taxa within or close to the Plagiogrammaceae. The results indicated that the Plagiogrammaceae evolved more than 114 million year ago and its diversification appears to correspond to a time of climate cooling. Additionally, we described a new monotypic genus (Coccinelloidea) with one new species C. gracilis, and five new species within established genera, e.g. Plagiogramma marginalis, Plagiogramma harenae, Plagiogramma porcipellis, Neofragilaria montgomeryii and Psammogramma anacarae.

Exploring Diversity, Taxonomy and Phylogeny of Diatoms (Bacillariophyta) from Marine Habitats. Novel Taxa with Internal Costae

In many marine littoral and sublittoral benthic habitats, we find small diatoms with few features resolvable with light microscopy (LM) other than internal costae across their valves. While classically those internal costae have defined their identification and classification, the use of electron microscopy and of molecular data have started to reveal the true diversity of unrelated forms and genera (e.g., Anaulus, Eunotogramma, Hustedtiella, or Plagiogramma) which possess these structures. Here we describe the new genus Ambo, in an attempt to clarify some of the polyphyly of taxa with internal costa by formally transferring Anaulus balticus, Anaulus simonsenii, and Plagiogramma tenuissimum as well as Ambo gallaeciae, described here. Related to this, we attempt to document and characterize the genus Anaulus itself, which was formally described by Ehrenberg with an illustration. A search by LM of mica designated by Ehrenberg as the holotype of Anaulus scalaris, the generitype of Anaulus, failed to recover a specimen which adequately describes the genus to the exclusion of other genera with internal costa. We also present morphological and molecular data for Anaulus creticus and suggest a new genus-Ceratanaulus-to reflect the distinct morphological and molecular characters we documented.

P925 An analysis of the impact of etiology vs. impact of hemodynamic variables on the right ventricular free wall deformation in patients with pulmonary hypertension

Purpose

Pulmonary hypertension (PH) is a deadly disease leading to right ventricular (RV) failure. The aim of this study was to establish whether aetiology of PH has a greater impact on RV longitudinal deformation than cardiac catherization parameters.

Methods

We retrospectively analyzed echocardiographic studies and cardiac catherization parameters of 25 patients with pulmonary hypertension : 13 pts with precapillary PH associated with atrial/ventricular septum defect and 12 pts with postcapillary PH due to dilated cardiomyopathy. We measured regional strain and regional systolic and diastolic strain rates (SR) in right ventricular free wall in basal, mid and apical segments.

Results

Aside from TAPSE, echocardiographic parameters indicate no difference. Even though mean pulmonary arterial pressure and pulmonary vascular residence significantly higher in patients with precapillary PH, strain was significantly decreased in patients with postcapillary PH. Statistically significant differences were observed between pre- and postcapillary PH patients" strain in apical and mid myocardial segments. Early diastolic strain rate (SR) in apical RV segment in precapillary PH patients was significantly higher than in patients with postcapillary PH. In other myocardial segments there were no differences between systolic, early diastolic and late diastolic SR.

Conclusion

Our study suggests that RV free wall strain in patients with PH moderately correlate with aetiology of PH. We did not find correlation between higher RA pressure or PVR and worsening of RV function in PH of different aetiologies.

Precapillary PH Postcapillary PH p value PA mean pressure (mmHG) 75,2 ± 17,7 42,0 ± 7,3 <0,05 PWR (WU) 15,8 ± 6,7 4,7 ± 2,6 <0,05 RV wall thickenss (mm) 11,0 ± 2,5 5,5 ± 1,0 NS RVIT (mm) 42,7 ± 10,4 42,8 ± 8,1 NS TAPSE (mm) 19,2 ± 4,2 15,6 ± 4,9 <0,05 S" 10,8 ± 2,0 9,4 ± 2,1 NS basal segment strain -16 ± 7 -17 ± 5 NS mid segment strain -18 ± 8 -15 ± 4 <0,05 apical segment strain -19 ± 8 -14 ± 4 <0,05

Complete chloroplast genome of the tiny marine diatom Nanofrustulum shiloi (Bacillariophyta) from the Adriatic Sea

We report the chloroplast genome sequence of Nanofrustulum shiloi, a tiny araphid pennate diatom collected from the Adriatic Sea. The 160,994-bp N. shiloi genome displays a quadripartite structure and its gene repertoire resembles those of other diatom chloroplast genomes. Besides the genes located in the inverted repeat, psbY is duplicated. A gene-poor region in the large single-copy region contains multiple ORFs sharing sequence similarities with plasmids and chloroplast ORFs found in other diatom species. The genome features a single intron, a group II intron in petB. Phylogenomic analysis identified N. shiloi at a basal position within the araphid 2 clade.

P3738Clinical outcomes after early vs new generation TAVR device deployment

Background

Whether newer generation devices influence early and long-term outcomes post-TAVR in a real life setting is unknown.

Aim

To assess impact of an early vs a new generation transcatheter heart valves (THV) on clinical outcomes (30-day and -years) in a real life scenario.

Methods

Out of 445 consecutive pts treated between 8/2009 and 10/2017 within the single-center, prospective TAVR Registry, there were 432 [median 83.0 years of age, 63.4% female] with device success (97.1%) as per VARC-2. Early generation THV included: CoreValve; Edwards SAPIEN or SAPIEN XT. Newer generation devices included: Evolut-R/-Pro; Acurate neo; Engager, SAPIEN 3; or Lotus Edge Aortic Valve System.

Results

Median follow-up was 29.3 (15.8–53.1) months with 100% 1-year follow-up. Early generation devices were deployed in 60.6% (n=262) and new devices in 39.4% (n=170). Pts treated with newer devices had more peripheral arterial disease (PAD) and more frequent PCI history (17.1% vs 8.8%, p=0.015, and 35.3% vs 26.7%, p=0.068 respectively); other demographic and clinical data were alike. Baseline aortic valve area and LV ejection fraction were similar between early and newer devices. Pre-dilation was less frequent with newer devices (41.8% vs 70.6%, p<0.001), whereas THV size, contrast volume, fluoroscopy time, radiation dose, and post-procedure aortic valve gradients were similar. Moderate PVL assessed early post-TAVR was recognized with same frequency between earlier vs newer devices (28.2% vs 28.6%). An VARC-2 safety endpoint was recognized more often among pts treated with early vs new devices (30.5% vs 21.8%, p=0.028, respectively), with more frequent: 30-day death (3.8% vs 1.8%, p=0.177), life-threatening or disabling bleeding (8.4% vs 5.3%, p=0.181), major vascular complications (20.2% vs 15.3%, p=0.121), and new permanent pacemaker implantation (22.9% vs 10.0%, p=0.001) with early devices, but similar frequencies of stroke and acute kidney injury (1.9% vs 1.8% and 3.8% vs 5.9%, respectively). The 1-year mortality rates were similar (13.4% vs 13.5%, respectively), with similar estimated midterm (1–2 years) prognosis, but worse estimated very long-term follow-up for newer THV devices (fig 1).

Figure 1

Conclusions

Newer TAVR devices with smaller delivery system size, although deployed in pts with more PAD and PCI history, are associated with less frequent occurrence of an VARC-2 safety endpoint and less frequent permanent pacemaker implantation. The 1-year and midterm (1–2 years) prognosis are similar for early and newer devices, whereas the longer follow-up could have been influenced by intrinsic pt characteristics (more frequent PAD and history of PCI).