83 research outputs found
Re-discovery of a "living fossil" coccolithophore from the coastal waters of Japan and Croatia
The extant coccolithophore Tergestiella adriatica Kamptner, which had not been reported since its original description in 1940, was recently re-discovered in coastal-nearshore waters at Tomari, Tottori (Japan) and offshore Rovinj (Croatia). Morphological analysis shows that extant Tergestiella and the Mesozoic genus Cyclagelosphaera (Watznaueriaceae), thought to have been extinct since the early Eocene (~. 54. Ma), are virtually identical. Molecular phylogenetic study supports the inference that T. adriatica is a direct descendent of Cyclagelosphaera. It is therefore a remarkable example of a living fossil. Our documentation of patchy coastal distribution in living T. adriatica and records of rare occurrences of fossil Cyclagelosphaera in Oligocene-Miocene shallow water sediments. , from the New Jersey shelf, suggest that Tergestiella/. Cyclagelosphaera was restricted to nearshore environments during much of the Cenozoic. This restricted ecology explains the lack of fossil Tergestiella/. Cyclagelosphaera recorded in open ocean sediments deposited during the last 54. myr.Floristic study of coccolithophores in the coastal and offshore waters of Tomari over a six-year period, show that T. adriatica occurs synchronously with the unusual neritic species, Braarudosphaera bigelowii, in mid-June. The environmental factors that induce the co-occurrence of these two taxa are uncertain, and T. adriatica did not co-occur with B. bigelowii at any other sites
Correction to: Rapid turnover of life-cycle-related genes in the brown algae.
Following publication of the original article [1], it was noticed that the author names were published with initials instead of full names. The article [1] has been updated
Rapid turnover of life-cycle-related genes in the brown algae.
Sexual life cycles in eukaryotes involve a cyclic alternation between haploid and diploid phases. While most animals possess a diploid life cycle, many plants and algae alternate between multicellular haploid (gametophyte) and diploid (sporophyte) generations. In many algae, gametophytes and sporophytes are independent and free-living and may present dramatic phenotypic differences. The same shared genome can therefore be subject to different, even conflicting, selection pressures during each of the life cycle generations. Here, we analyze the nature and extent of genome-wide, generation-biased gene expression in four species of brown algae with contrasting levels of dimorphism between life cycle generations.
We show that the proportion of the transcriptome that is generation-specific is broadly associated with the level of phenotypic dimorphism between the life cycle stages. Importantly, our data reveals a remarkably high turnover rate for life-cycle-related gene sets across the brown algae and highlights the importance not only of co-option of regulatory programs from one generation to the other but also of a role for newly emerged, lineage-specific gene expression patterns in the evolution of the gametophyte and sporophyte developmental programs in this major eukaryotic group. Moreover, we show that generation-biased genes display distinct evolutionary modes, with gametophyte-biased genes evolving rapidly at the coding sequence level whereas sporophyte-biased genes tend to exhibit changes in their patterns of expression.
Our analysis uncovers the characteristics, expression patterns, and evolution of generation-biased genes and underlines the selective forces that shape this previously underappreciated source of phenotypic diversity
Life history and morphological studies of Punctaria tenuissima (Chordariaceae, Phaeophyceae), a new record for the Azores
Copyright © 2010 by Walter de Gruyter.Punctaria tenuissima (Chordariaceae, Phaeophyceae) is reported for the first time from the Azores. Erect thalli were collected on the Island of SaËo Miguel; they were up to 3 cm long, flattened and often twisted. The plurilocular sporangia were formed from surface cells that were quadrate or rectangular in surface view. Unilocular sporangia were not observed in the field. In culture, the plurispores of P. tenuissima developed into Hecatonema-like, tufted, prostrate thalli that formed plurilocular sporangia. The plurispores of the prostrate thalli cultured at 158C with a long day (LD) photoperiod developed into new prostrate thalli, which in turn formed plurilocular sporangia. This cycle was repeated 5 times, resulting in several generations of reproductive prostrate thalli. When these cultures were cooled to 108C with a short day (SD) photoperiod, new erect thalli developed from the prostrate thalli resembling the thalli collected in the field. These erect blades produced unilocular and plurilocular sporangia on the same or on different thalli. The plurispores and unispores produced by the erect thalli at 108C under SD conditions once again developed into new prostrate thalli. This is the first report of unilocular sporangia formed in cultures of P. tenuissima. Sexual reproduction was not observed. The culture conditions, particularly temperature and daylength, appeared to influence the formation of erect blades. The Punctaria-like thalli were produced in 108C/SD conditions, whilst the Hecatonema-like thalli were produced under 108â158C/LD and SD conditions. These results are similar to those reported for P. tenuissima from other locations and suggest the occurrence of both direct and heteromorphic life histories in the Azorean algae
Advances in IVUS/OCT and Future Clinical Perspective of Novel Hybrid Catheter System in Coronary Imaging
Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have been
developed and improved as both diagnostic and guidance tools for interventional
procedures over the past three decades. IVUS has a resolution of 100”m with a
high tissue penetration and capability of assessing the entire structure of a coronary
artery including the external elastic membrane, whereas OCT has a higher resolution of
10â20”m to assess endoluminal structures with a limited tissue penetration compared
to IVUS. Recently, two companies, CONAVI and TERUMO, integrated IVUS and OCT into
a single catheter system. With their inherent strength and limitations, the combined IVUS
and OCT probes are complementary and work synergistically to enable a comprehensive
depiction of coronary artery. In this review, we summarize the performance of the two
intracoronary imaging modalit
Cryptic Haploid Stages in the Life Cycle of Leathesia marina (Chordariaceae, Phaeophyceae) Under In Vitro Culture
We evaluated the life cycle of Leathesia marina through molecular analyses, culture studies, morphological observations, and ploidy measurements. Macroscopic sporophytes were collected from two localities in Atlantic Patagonia and were cultured under long-day (LD) and short-day (SD) conditions. Molecular identification of the microscopic and macroscopic phases was performed through the cox3 and rbcL genes and the phylogeny was assessed on the basis of single gene and concatenated datasets. Nuclear ploidy of each phase was estimated from the DNA contents of individual nuclei through epifluorescence microscopy and flow cytometry. Molecular results confirmed the identity of the Argentinian specimens as L. marina and revealed their conspecificity with L. marina from New Zealand, Germany, and Japan. The sporophytic macrothalli (2n) released mitospores from plurilocular sporangia, which developed into globular microthalli (2n), morphologically similar to the sporophytes but not in size, constituting a generation of small diploid thalli, with a mean fluorescent nuclei cross-sectional area of 3.21 ± 0.7 Όm2. The unilocular sporangia released meiospores that developed two morphologically different types of microthalli: erect branched microthalli (n) with a nuclear area of 1.48 ± 0.07 ”m2 that reproduces asexually, and prostrate branched microthalli (n) with a nuclear area of 1.24 ± 0.10 ”m2 that reproduces sexually. The prostrate microthalli released gametes in LD conditions, which merged and produced macroscopic thalli with a nuclear cross-sectional area of 3.45 ± 0.09 ”m2. Flow cytometry confirmed that the erect and prostrate microthalli were haploid and that the globular microthalli and macrothalli were diploid.Fil: Poza, Ailen Melisa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: Santiañez, Wilfred John E.. Hokkaido University; JapĂłn. University of the Philippines Diliman; FilipinasFil: Croce, Maria Emilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; Argentina. Universidad Nacional del Sur. Departamento de BiologĂa, BioquĂmica y Farmacia; ArgentinaFil: Gauna, Maria Cecilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; Argentina. Universidad Nacional del Sur. Departamento de BiologĂa, BioquĂmica y Farmacia; ArgentinaFil: Kogame, Kazuhiro. Hokkaido University; JapĂłnFil: Parodi, Elisa Rosalia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; Argentin
Influence of Bleeding Risk on Outcomes of Radial and Femoral Access for Percutaneous Coronary Intervention: An Analysis From the GLOBAL LEADERS Trial
Background: Radial artery access has been shown to reduce mortality and bleeding events, especially in patients with acute coronary syndromes. Despite this, interventional cardiologists experienced in femoral artery access still prefer that route for percutaneous coronary intervention. Little is known regarding the merits of each vascular access in patients stratified by their risk of bleeding. Methods: Patients from the Global Leaders trial were dichotomized into low or high risk of bleeding by the median of the PRECISE-DAPT score. Clinical outcomes were compared at 30 days. Results: In the overall population, there were no statistical differences between radial and femoral access in the rate of the primary end point, a composite of all-cause mortality, or new Q-wave myocardial infarction (MI) (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.42-1.15). Radial access was associated with a significantly lower rate of the secondary safety end point, Bleeding Academic Research Consortium (BARC) 3 or 5 bleeding (HR 0.55, 95% CI 0.36-0.84). Compared by bleeding risk strata, in the high bleeding score population, the primary (HR 0.47, 95% CI 0.26-0.85; P = 0.012; Pinteraction = 0.019) and secondary safety (HR 0.57, 95% CI 0.35-0.95; P = 0.030; Pinteraction = 0.631) end points favoured radial access. In the low bleeding score population, however, the differences in the primary and secondary safety end points between radial and femoral artery access were no longer statistically significant. Conclusions: Our findings suggest that the outcomes of mortality or new Q-wave MI and BARC 3 or 5 bleeding favour radial access in patients with a high, but not those with a low, risk of bleeding. Because thisContexte : Il a et e d emontr e que l âaccĂšs par lâartĂšre radiale reduit la
mortalite et les h emorragies, en particulier chez les patients
presentant un syndrome coronarien aigu. Malgr e cela, les cardiologues
interventionnels qui ont acquis de lâexperience en matiĂšre d âaccĂšs par
lâartĂšre femorale pr efĂšrent encore utiliser cette voie lorsqu âils doivent
pratiquer une intervention coronarienne percutanee. On connaĂźt mal lâinterĂȘt de chacune de ces techniques d âaccĂšs vasculaire au regard du
risque dâhemorragie.
Methodologie : Les patients de lâessai GLOBAL LEADERS ont et e
repartis en deux groupes, selon qu âils presentaient un risque
dâhemorragie faible ou elev e d âaprĂšs le score PRECISE-DAPT median,
puis les resultats cliniques ont et e compar es Ă 30 jours.
Resultats : Dans lâensemble de la population, aucune difference sta-
tistiquement significative nâa et e observ ee entre l âaccĂšs radial et
lâaccĂšs femoral quant au critĂšre d âevaluation principal, compos e de la
mortalite toutes causes confondues et d âun nouvel infarctus du myocarde (IM) avec onde Q (rapport des risques instantanes [RRI] de 0,70;
intervalle de confiance [IC] Ă 95 % : 0,42-1,15). LâaccĂšs radial a et e
associe Ă un taux signi ficativement plus faible de survenue du critĂšre
secondaire dâevaluation de l âinnocuite, c âest-Ă -dire une hemorragie de
type 3 ou 5 selon la classification du BARC (Bleeding Academic
Research Consortium) (RRI de 0,55; IC Ă 95 % : 0,36-0,84). Lorsquâon
compare les sujets en fonction du risque dâhemorragie, les critĂšres
dâevaluation de l âinnocuite principal (RRI de 0,47; IC Ă 95 % : 0,26-
0,85; p ÂŒ 0,012; pinteraction ÂŒ 0,019) et secondaire (RRI de 0,57; IC Ă
95 % : 0,35-0,95; p ÂŒ 0,030; pinteraction ÂŒ 0,631) sont favorables Ă
lâaccĂšs radial au sein de la population presentant un risque d âhemor-
ragie elev e. Dans la population pr esentant un risque d âhemorragie
faible, les differences entre l âaccĂšs radial et lâaccĂšs femoral quant aux
critĂšres dâevaluation de l âinnocuite principal et secondaire ne sont
toutefois plus statistiquement significatives.
Conclusions : Selon ces observations, les resultats concernant la
mortalite ou la survenue d âun nouvel IM avec onde Q et le risque
dâhemorragie de type 3 ou 5 selon la classi fication du BARC indiquent
que lâaccĂšs radial serait Ă privilegier lorsque le risque d âhemorragie est
elev e, mais pas lorsqu âil est faible. Comme il ne sâagissait pas dâune
analyse principale, il convient de considerer ces observations comme
etant g en eratrices d âhypothĂšses
The influence of implantation techniques on lesion oriented-outcomes in Absorb BVS and Xience EES lesions treated in routine clinical practice at complete three year follow-up: AIDA trial QCA substudy
It has been hypothesized that dedicated optimized Absorb BVS implantation techniques might mitigate the risk of adverse events such as target vessel
Impact of renal function on clinical outcomes after PCI in ACS and stable CAD patients treated with ticagrelor: a prespecified analysis of the GLOBAL LEADERS randomized clinical trial
Background: Impaired renal function (IRF) is associated with increased risks of both ischemic and bleeding events. Ticagrelor has been shown to provide greater absolute reduction in ischemic risk following acute coronary syndrome (ACS) in those with versus without IRF. Methods: A pre-specified sub-analysis of the randomized GLOBAL LEADERS trial (n = 15,991) comparing the experimental strategy of 23-month ticagrelor monotherapy (after 1-month ticagrelor and aspirin dual anti-platelet therapy [DAPT]) with 12-month DAPT followed by 12-month aspirin after percutaneous coronary intervention (PCI) in ACS and stable coronary artery disease (CAD) patients stratified according to IRF (glomerular filtration rate < 60Â ml/min/1.73Â m2). Results: At 2Â years, patients with IRF (n = 2171) had a higher rate of the primary endpoint (all-cause mortality or centrally adjudicated, new Q-wave myocardial infarction [MI](hazard ratio [HR] 1.64, 95% confidence interval [CI] 1.35â1.98, padj = 0.001), all-cause death, site-reported MI, all revascularization and BARC 3 or 5 type bleeding, compared with patients without IRF. Among patients with IRF, there were similar rates of the primary endpoint (HR 0.82, 95% CI 0.61â1.11, p = 0.192, pint = 0.680) and BARC 3 or 5 type bleeding (HR 1.10, 95% CI 0.71â1.71, p = 0.656, pint = 0.506) in the experimental versus the reference group. No significant interactions were seen between IRF and treatment effect for any of the secondary outcome variables. Among ACS patients with IRF, there were no between-group differences in the rates of the primary endpoint or BARC 3 or 5 type bleeding; however, the rates of the patient-oriented composite endpoint (POCE) of all-cause death, any stroke, MI, or revascularization (pint = 0.028) and net adverse clinical events (POCE and BARC 3 or 5 type bleeding) (pint = 0.045), were lower in the experimental versus the reference group. No treatment effects were found in stable CAD patients categorized according to presence of IRF. Conclusions: IRF negatively impacted long-term prognosis after PCI. There were no differential treatment effects found with regard to all-cause death or new Q-wave MI after PCI in patients with IRF treated with ticagrelor monotherapy. Clinical trial regis
Usefulness of the updated logistic clinical SYNTAX score after percutaneous coronary intervention in patients with prior coronary artery bypass graft surgery: Insights from the GLOBAL LEADERS trial
Objectives: We aimed to investigate the prognostic utility of the anatomical CABG SYNTAX and logistic clinical SYNTAX scores for mortality after percutaneous coronary intervention (PCI) in patients with prior coronary artery bypass grafts (CABG). Background: The anatomical SYNTAX score evaluated the anatomical complexity of coronary artery disease and helped predict the prognosis of patients undergoing PCI. The anatomical CABG SYNTAX score was derived from the anatomical SYNTAX score in patients with prior CABG, whilst the logistic clinical SYNTAX score was developed by incorporating clinical factors into the anatomical SYNTAX score. Methods: We calculated the anatomical CABG SYNTAX score and logistic clinical SYNTAX score in 205 patients in the GLOBAL LEADERS trial. The predictive abilities of these scores for 2-year all-cause mortality were evaluated. Results: Using the median scores as categorical thresholds between low and high score groups, the logistic clinical SYNTAX score was able to discriminate the risk of 2-year mortality, unlike the anatomical CABG SYNTAX score. The logistic clinical SYNTAX was significantly better at predicting 2-year mortality, compared to the anatomical CABG SYNTAX score, as evidenced by AUC values in receiver-operating characteristic curve analysis (0.806 vs. 0.582, p <.001) and integrated discrimination improvement (0.121, p <.001). Conclusions: The logistic clinical SYNTAX score was superior to the anatomical CABG SYNTAX score in predicting 2-year mortality
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