143 research outputs found
Characteristics of survivors: growth and nutritional condition of early stages of the hake species Merluccius paradoxus and M. capensis in the southern Benguela ecosystem
Larval mortality in marine fish is strongly linked to characteristic traits such as growth and condition, but the variability in these traits is poorly understood. We tried to identify the variability in growth in relation to conditions leading to greater survival chances for early stages of Cape hake, Merluccius paradoxus and M. capensis, in the Benguela upwelling ecosystem. During two cruises in 2007 and one cruise in 2008, hake larvae and juveniles were caught. Otolith microstructures revealed a larval age ranging from 2 to 29 days post-hatching (dph), whereas juvenile age was 67â152 dph. RNA:DNA ratios, used to evaluate nutritional condition, were above the relevant threshold level for growth. No strong coupling between growth and condition was detected, indicating a complex relationship between these factors in the southern Benguela ecosystem. Merluccius paradoxus juveniles caught in 2007 (the surviving larvae of 2006) had significantly higher larval growth rates than larvae hatched in 2007 and 2008, possibly indicating selection for fast growth in 2006. High selection pressure on growth could be linked to predation avoidance, including cannibalism
Reviewing evidence of marine ecosystem change off South Africa
Recent changes have been observed in South African marine ecosystems. The main pressures on these
ecosystems are fishing, climate change, pollution, ocean acidification and mining. The best long-term datasets are
for trends in fishing pressures but there are many gaps, especially for non-commercial species. Fishing pressures
have varied over time, depending on the species being caught. Little information exists for trends in other
anthropogenic pressures. Field observations of environmental variables are limited in time and space. Remotely
sensed satellite data have improved spatial and temporal coverage but the time-series are still too short to
distinguish long-term trends from interannual and decadal variability. There are indications of recent cooling on the
West and South coasts and warming on the East Coast over a period of 20 - 30 years. Oxygen concentrations on the
West Coast have decreased over this period. Observed changes in offshore marine communities include southward
and eastward changes in species distributions, changes in abundance of species, and probable alterations in
foodweb dynamics. Causes of observed changes are difficult to attribute. Full understanding of marine ecosystem
change requires ongoing and effective data collection, management and archiving, and coordination in carrying out
ecosystem research.DHE
Residual plaque burden in patients with acute coronary syndromes after successful percutaneous coronary intervention
Objectives: The aim of this study was to characterize and evaluate the clinical impact of untreated atherosclerotic disease after percutaneous coronary intervention (PCI) in patients with acute coronary syndromes (ACS). Background: Residual atherosclerotic disease after successful PCI may predispose future major adverse cardiovascular events (MACE). Compared with intravascular ultrasound (IVUS), angiography underestimates the presence and severity of coronary artery disease. Methods: Following successful PCI of all clinically significant lesions in 697 patients with ACS, 3-vessel grayscale and radiofrequency IVUS was performed. Lesions were prospectively characterized, and patients were followed for a median of 3.4 years. A total of 3,229 untreated lesions (4.89 ± 1.98 lesions/patient) were identified by IVUS, with mean plaque burden (PB) of 49.6 ± 4.2%. Results: By angiography these nonculprit lesions were mild, with mean diameter stenosis of 38.9 ± 15.3%. At least 1 lesion with a PB <70% (PB70 lesion) was found in 220 (33%) patients. By multivariable analysis, a history of prior PCI and angiographic 3-vessel disease were independent predictors of PB70 lesions. Patients with PB70 lesions had greater total percent plaque volume, normalized PB, fibroatheromas, thin-cap fibroatheromas, and normalized volumes of necrotic core and dense calcium. Patients with PB70 lesions had greater 3-year rates of MACE due to untreated nonculprit lesions (20.8% vs. 7.7%, p < 0.0001). Among imaged nonculprit lesions, the proportion of PB70 lesions causing MACE was significantly greater than non-PB70 lesions (8.7% vs. 1.0%, p < 0.0001). Conclusions: After successful PCI of all angiographically significant lesions, overall untreated atherosclerotic burden remains high, and PB70 lesions are frequently present in the proximal and mid-coronary tree. Patients with PB70 lesions have greater atherosclerosis throughout the coronary tree, have more thin-cap fibroatheromas, and are at increased risk for future cardiovascular events. (PROSPECT: An Imaging Study in Patients With Unstable Atherosclerotic Lesions; NCT00180466
Tasquinimod suppresses tumor cell growth and bone resorption by targeting immunosuppressive myeloid cells and inhibiting c-MYC expression in multiple myeloma
Background: Immunotherapy emerged as a promising treatment option for multiple myeloma (MM) patients. However, therapeutic efficacy can be hampered by the presence of an immunosuppressive bone marrow microenvironment including myeloid cells. S100A9 was previously identified as a key regulator of myeloid cell accumulation and suppressive activity. Tasquinimod, a small molecule inhibitor of S100A9, is currently in a phase Ib/IIa clinical trial in MM patients (NCT04405167). We aimed to gain more insights into its mechanisms of action both on the myeloma cells and the immune microenvironment.
Methods: We analyzed the effects of tasquinimod on MM cell viability, cell proliferation and downstream signaling pathways in vitro using RNA sequencing, real-time PCR, western blot analysis and multiparameter flow cytometry. Myeloid cells and T cells were cocultured at different ratios to assess tasquinimod-mediated immunomodulatory effects. The in vivo impact on immune cells (myeloid cell subsets, macrophages, dendritic cells), tumor load, survival and bone disease were elucidated using immunocompetent 5TMM models.
Results: Tasquinimod treatment significantly decreased myeloma cell proliferation and colony formation in vitro, associated with an inhibition of c-MYC and increased p27 expression. Tasquinimod-mediated targeting of the myeloid cell population resulted in increased T cell proliferation and functionality in vitro. Notably, short-term tasquinimod therapy of 5TMM mice significantly increased the total CD11b+ cells and shifted this population toward a more immunostimulatory state, which resulted in less myeloid-mediated immunosuppression and increased T cell activation ex vivo. Tasquinimod significantly reduced the tumor load and increased the trabecular bone volume, which resulted in prolonged overall survival of MM-bearing mice in vivo.
Conclusion: Our study provides novel insights in the dual therapeutic effects of the immunomodulator tasquinimod and fosters its evaluation in combination therapy trials for MM patients
Carotid Artery Stenting Using a Novel Self-Expanding Braided NickelâTitanium Stent: Feasibility and Safety Porcine Trial
We studied the deliverability and safety of a braided, self-expanding, closed-cell nickelâtitanium (NiTi) stent (E-volution, Jotec GmbH, Hechingen, Germany) especially designed for the endovascular treatment of carotid artery bifurcation stenosis with special regard to in-stent stenosis and thrombosis compared with a laser-cut reference nitinol stent in a porcine model of percutaneous vascular interventions. We aimed to assess histopathologic response in minipig carotid and subclavian arteries. Eight minipigs received a total of 42 stents: 14 reference stents and 28 E-volution stents. Eleven of the E-volution stents were additionally coated with heparin. Control angiography was obtained immediately before and after vascular intervention as well as 4 weeks after the procedure. Primary endpoints were 28 days of angiographic analyses as well as histomorphometric analysis, including injury score, inflammation score, luminal diameter, vessel diameter, maximal neointimal thickness, and area of in-stent stenosis. Secondary end points were procedural success, 28-day mortality, and stent thrombosis. All stents could be delivered successfully without procedural complications, morbidity, or mortality during our observation time. As confirmed by histology, no in-stent thrombosis was observed. Compared with common carotid arteries, subclavian arteries are significantly more vulnerable to developing in-stent stenosis caused by neointima proliferation (p < 0.05). Compared with the use of 1 single stent/artery, serial application of two stents leads to a more excessive but not significantly different neointimal proliferation (p > 0.05). The E-volution stent, especially when heparin coated, is in line with the comparison to the laser-cut reference stent displaying similar results of angiographic, histologic, and histomorphometric analyses (p > 0.05). Compared with the reference laser-cut stent, the self-expanding nitinol stent (E-volution) with its advanced braiding technology is feasible and safe. In our opinion, the high radial resistive force and the advanced braided design with tight stent-strut interstices may be beneficial in terms of plaque stabilization. Further studies are necessary and warranted
Cryptic species in a well-known habitat: applying taxonomics to the amphipod genus Epimeria (Crustacea, Peracarida)
Taxonomy plays a central role in biological sciences. It provides a communication system for scientists as it aims to enable correct identification of the studied organisms. As a consequence, species descriptions should seek to include as much available information as possible at species level to follow an integrative concept of âtaxonomicsâ. Here, we describe the cryptic species Epimeria frankei sp. nov. from the North Sea, and also redescribe its sister species, Epimeria cornigera. The morphological information obtained is substantiated by DNA barcodes and complete nuclear 18S rRNA gene sequences. In addition, we provide, for the first time, full mitochondrial genome data as part of a metazoan species description for a holotype, as well as the neotype. This study represents the first successful implementation of the recently proposed concept of taxonomics, using data from highthroughput technologies for integrative taxonomic studies, allowing the highest level of confidence for both biodiversity and ecological research
Influence of convolution filtering on coronary plaque attenuation values: observations in an ex vivo model of multislice computed tomography coronary angiography
Attenuation variability (measured in Hounsfield Units, HU) of human coronary plaques using multislice computed tomography (MSCT) was evaluated in an ex vivo model with increasing convolution kernels. MSCT was performed in seven ex vivo left coronary arteries sunk into oil followingthe instillation of saline (1/â) and a 1/50 solution of contrast material (400 mgI/ml iomeprol). Scan parameters were: slices/collimation, 16/0.75 mm; rotation time, 375 ms. Four convolution kernels were used: b30f-smooth, b36f-medium smooth, b46f-medium and b60f-sharp. An experienced radiologist scored for the presence of plaques and measured the attenuation in lumen, calcified and noncalcified plaques and the surrounding oil. The results were compared by the ANOVA test and correlated with Pearsonâs test. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. The mean attenuation values were significantly different between the four filters (pâ<â0.0001) in each structure with both solutions. After clustering for the filter, all of the noncalcified plaque values (20.8â±â39.1, 14.2â±â35.8, 14.0â±â32.0, 3.2â±â32.4 HU with saline; 74.7â±â66.6, 68.2â±â63.3, 66.3â±â66.5, 48.5â±â60.0 HU in contrast solution) were significantly different, with the exception of the pair b36fâb46f, for which a moderate-high correlation was generally found. Improved SNRs and CNRs were achieved by b30f and b46f. The use of different convolution filters significantly modifief the attenuation values, while sharper filtering increased the calcified plaque attenuation and reduced the noncalcified plaque attenuation
Comparison of clinical outcomes between Magmaris and Orsiro drug eluting stent at 12âŻmonths: Pooled patient level analysis from BIOSOLVE IIâIII and BIOFLOW II trials
Background: The aim of this study was to compare the 12-month clinical outcomes of patients treated with Magmaris or Orsiro. Second generation drug-eluting absorbable metal scaffold Magmaris (Dreams 2G) has proved to be safe and effective in the BIOSOLVE-II study. Similarly, biodegradable polymer sirolimus-eluting stent, Orsiro has shown notable clinical results even in all-comer populations. Methods: Magmaris group patients were taken from the BIOSOLVE-II and BIOSOLVE-III trials, while the patients from Orsiro group were enrolled in BIOFLOW-II trial. The primary outcome was explored using a time-to-event assessment of the unadjusted clinical outcomes for target lesion failure (TLF) at 12 months, followed by a multivariate analysis adjusting for all the significantly different covariates between the groups. Results: The study population consisted of 482 patients (521 lesions), 184 patients (189 lesions) in Magmaris group and 298 patients (332 lesions) in Orsiro group. The mean age was 65.5 ± 10.8 and 62.7 ± 10.4 years in Magmaris and Orsiro groups, respectively (p = 0.005). Magmaris and Orsiro unadjusted TLF rates were 6.0 and 6.4% with no significant difference between the groups (p = 0.869). In the multivariate analysis, there were no meaningful differences between Magmaris and Orsiro groups. Finally, none of the groups presented device thrombosis cases at 12 months. Conclusion: At 12 months there were no significant differences between Magmaris and Orsiro groups neither in the unadjusted assessment nor in the multivariate analysis for target lesion failure. These results should be taken as hypothesis generating and may warrant a head to head comparison on a randomized fashion
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