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Computed tomography (CT) has emerged as a non-invasive method to identify coronary artery calcifications (CAC), a prognostic marker of major cardiacevents in asymptomatic patients. We aimed to investigate the association between incidental visualization of CAC in CT pulmonary angiography (CTPA) for PE suspicion and mid-term cardiovascular prognosis in patients without known coronary artery disease (CAD). This was a retrospective single center study including patients who underwent CTPA for suspected PE. Patients aged < 40 years, those with known CAD or with a final diagnosis of acute coronary syndrome, and those who died during the hospital stay were excluded. Patients were categorized in four groups according to the extent and severity of CAC: none (grade0), mild (grade1), moderate (grade 2) and severe (grade3) CAC. The primary outcome was a composite of cardiovascular mortality, myocardial infarction (MI) or coronary revascularization. The secondary outcomes were all-cause mortality, and an extended composite outcome including cardiovascular mortality, MI, coronary revascularization, ischaemic stroke, ischaemic peripheral events and hospitalization for heart failure. A total of 414 patients (mean age 69.7 ± 14.3 years, 42% males, out of whom 18.1% had PE) were included with the distribution presented in Figure 1 (PanelA). Patients with grades2-3 were older, more often males, with higher prevalence of traditional risk factors, chronic kidney disease (CKD) and prior stroke. The mean follow-up was 3.5 ± 2.4 years. The incidence of the primary outcome increased according to the 4 visual CAC categories (Figure 1, Panel B) with sharp difference between patients with grade 2 and 3 vs. those with grade 0 and 1. After adjustment for age, sex, risk factors, peripheral artery disease, CKD and PE diagnosis, the presence of grade 2–3 CAC predicted independently the primary outcome (HR = 5.30, 95%CI 2.56-10.98; P < 0.001). Grade 2-3 CAC were also independent predictors for all-cause mortality (HR = 1.52, 95%CI 1.10-2.11; P = 0.011); and the extended composite event (HR = 1.82, 95%CI 1.13-2.95; P = 0.014). Similar results were found in the subgroup of patients without PE after CTPA. Visual assessment of CAC in CT pulmonary angiography couldprovide important information regarding mid-term cardiovascular prognosisindependently from PE diagnosis. [ABSTRACT FROM AUTHOR] more...

Computed tomography (CT) has emerged as a noninvasive method to identify coronary artery calcifications (CAC). We sought to investigate the association between opportunistic visual CAC evaluation in patients without known coronary artery disease who underwent CT pulmonary angiography (CTPA) for pulmonary embolism (PE) suspicion, and cardiovascular prognosis. We analyzed data of patients who underwent CTPA for suspected PE in 2017 at CHU Dupuytren, Limoges, France. Patients were categorized into 4 groups according to a simple visual ordinal score to assess the extent and severity of CAC on a whole-patient basis: none (grade 0), mild (grade 1), moderate (grade 2), and severe (grade 3). The primary outcome was a composite of cardiovascular mortality, myocardial infarction (MI), or coronary revascularization. The secondary outcomes were all-cause mortality, and an extended composite outcome including cardiovascular mortality, MI, coronary revascularization, ischemic stroke, ischemic peripheral events, and hospitalization for heart failure. A total of 414 patients (mean age 69.7 ± 14.3 years, 42% men, 18.1% PE) were included in the analysis and subdivided according to CAC categories as follows: grade 0 (n = 123; 29.7%), grade 1 (n = 133; 32.1%), grade 2 (n = 79; 19.1%) and grade 3 (n = 79; 19.1%). The mean follow-up was 3.5 ± 2.4 years. After adjustment, the presence of CAC grade 2 to 3 CAC independently predicted the primary outcome (hazard ratio [HR] = 5.30, 95% CI 2.56 to 10.98, p <0.001). CAC grade 2 to 3 were also independent predictors for all-cause mortality (HR = 1.52, 95% CI 1.10 to 2.11, p = 0.011); and the extended composite event (HR = 1.82, 95% CI 1.13 to 2.95, p = 0.014). In conclusion, the opportunistic assessment of CAC in CTPA for suspected PE could provide important mid-term prognostic information, independently from the PE findings., Competing Interests: Declaration of competing interest Dr. Aboyans received research grants from Bayer, Boehringer Ingelheim, NovoNordisk, Sanofi, and Vifor. The remaining authors have no competing interests to declare., (Copyright © 2024 Elsevier Inc. All rights reserved.) more...

Graphene oxide (GO) nanosheets were functionalized with Schiff base and reduced Schiff base. Covalent and non-covalent functionalized GO nanostructures have been tested for the removal of pesticides with different chemical structures and properties (e.g., Epoxiconazole, Dimethomorph, Cyprodinil, Chlorothalonil, Acetochlor, Trifluralin) from aqueous solutions. The structure and morphology characteristics of the prepared structures were analyzed using techniques such as solid-state nuclear magnetic resonance (SSNMR), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Results of the experiments showed that, although the non-covalent functionalization did not affect the adsorption properties of GO much, the covalent functionalization increased the adsorption capacity of GO against the mentioned pesticides. more...

While long-acting injectable treatments are gaining increasing interest in managing chronic diseases, the available drug delivery systems almost exclusively rely on hydrophobic matrixes, limiting their application to either hydrophobic drugs or large and hydrophilic molecules such as peptides. To address the technological lock for long-acting delivery systems tailored to small, hydrophilic drugs such as anticancer and antiviral nucleoside/nucleotide analogues, we have synthesized and characterized an original approach with a multi-scale structure: (i) a nucleotide (adenosine triphosphate, ATP) is first incorporated in hydrophilic chitosan-Fe(III) nanogels; (ii) these nanogels are then transferred by freeze-drying and resuspension into a water-free, hydrophobic medium containing PLGA and an organic solvent, N-methyl-2-pyrrolidone. We show that this specific association allows an injectable and homogeneous dispersion, able to form in situ implants upon injection in physiological or aqueous environments. This system releases ATP in vitro without any burst effect in a two-step mechanism, first as nanogels acting as an intermediate reservoir over a week, then as free drug over several weeks. In vivo studies confirmed the potential of such nanostructured implants for sustained drug release following subcutaneous injection to mice hock, opening perspectives for sustained and targeted delivery through the lymphatic system., (© 2024. Controlled Release Society.) more...

In recent years, the exploration of genome three-dimensional (3D) conformation has yielded profound insights into the regulation of gene expression and cellular functions in both animals and plants. While animals exhibit a characteristic genome topology defined by topologically associating domains (TADs), plants display similar features with a more diverse conformation across species. Employing advanced high-throughput sequencing and microscopy techniques, we investigated the landscape of 26 histone modifications and RNA polymerase II distribution in tomato ( Solanum lycopersicum ). Our study unveiled a rich and nuanced epigenetic landscape, shedding light on distinct chromatin states associated with heterochromatin formation and gene silencing. Moreover, we elucidated the intricate interplay between these chromatin states and the overall topology of the genome. Employing a genetic approach, we delved into the role of the histone modification H3K9ac in genome topology. Notably, our investigation revealed that the ectopic deposition of this chromatin mark triggered a reorganization of the 3D chromatin structure, defining different TAD-like borders. Our work emphasizes the critical role of H3K9ac in shaping the topology of the tomato genome, providing valuable insights into the epigenetic landscape of this agriculturally significant crop species., Competing Interests: Competing interests statement:The authors declare no competing interest. more...

Objectives: To evaluate the role of 4-dimensional (4D; 3-dimensional [3D] + time) analysis using multiphase cardiac computed tomography (MCCT) in the description of the aortic annulus (AA) of bicuspid aortic valves (BAV) with regard to the latest expert consensus classification., Methods: Electrocardiography-gated MCCT of 15 patients with BAV were analyzed using in-house software and compared to 15 patients with normal tricuspid aortic valve (TAV). The AA border was pinpointed on 9 reconstructed planes, and the 3D coordinates of the 18 consecutive points were interpolated in 3D using a cubic spline to calculate 3D areas, perimeters, diameters, eccentricity indexes, and global height. Measurements were repeated throughout the cardiac cycle (10 phases). Three additional planes were generated at the level of the left ventricular outflow tract (LVOT), the sinus of Valsalva, and the sinotubular junction., Results: The annulus area was significantly larger in BAV compared to TAV (mean indexed 3D area, 5.64 ± 0.84 cm 2 /m 2 vs 4.3 ± 0.38 cm 2 /m 2 , respectively; P  < .001). The AA was also larger in BAV in terms of perimeter, diameters, and height ( P  < .001). The Valsalva sinuses and sinotubular junction also were significantly larger in BAV compared to TAV (mean area in end-diastole, 6.06 ± 1.00 cm 2 vs 4.69 ± 1.00 cm 2 [ P  < .001] and 5.13 ± 1.62 cm 2 vs 3.62 ± 0.99 cm 2 [ P  < .001], respectively). In BAV, 3D AA shape analysis helps distinguish the 3 types of BAV: the 2-sinus type (symmetrical), the fused type, and the partial-fusion type or "form fruste" (both asymmetrical). It also allows determination of the position and height of the nonfunctional commissure. In symmetrical BAV, the nonfunctional commissure was significantly lower than the other commissures (6.01 ± 4.27 mm vs 18.24 ± 3.20 mm vs 17.15 ± 3.60 mm; P  < .001), whereas in asymmetrical BAV, the 3 commissures were of comparable height (16.38 ± 0.86 mm vs 15.88 ± 1.69 mm vs 15.37 ± 0.88 mm; P  = .316). There was no difference in AA eccentricity indices between TAV and BAV in all phases of the cardiac cycle; however, there was a spectrum of ellipticity for the other components of the aortic root among the different types of valves: going from TAV to asymmetrical BAV to symmetrical BAV, at end-diastole, the LVOT became more circular and the sinuses of Valsalva became more elliptical., Conclusions: 3D morphometric analysis of the BAV using MCCT allows identification of the type of BAV and the position and height of the nonfunctional commissure. There are significant differences in the morphology of the aortic root between TAV and the different types of BAV. Further studies are needed to evaluate the impact of 3D analysis on the procedural planning for pathologic BAV., Competing Interests: The authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (© 2024 The Author(s).) more...

Objectives: To evaluate the precise dimensions of the normal aortic root, especially the true aortic annulus, during the cardiac cycle using an innovative reconstruction method based on multiphase cardiac computed tomography and to assess the feasibility and the reproducibility of this method for aortic root analysis., Methods: Between January 2019 and June 2021, 30 optimal consecutive ECG-gated multiphase cardiac computed tomography of patients with normal tricuspid aortic valve were analysed using an in-house software. Aortic annulus border was pinpointed on 9 reconstructed planes and the 3D coordinates of the 18 consecutive points were interpolated into a 3D curve using a cubic spline. Three additional planes were generated at the level of the left ventricular outflow tract, the level of the Valsalva sinus and the level of the sinotubular junction. This procedure was repeated for all the 10 temporal phases of the RR interval., Results: The aortic annulus mean 3D and 2D areas were 7.67 ± 1.51 and 5.16 ± 1.40 cm2, respectively. The mean 2D diameter was 2.51 ± 0.23 cm. The mean global area expansion was 11.8 ± 3.5% and the mean perimeter expansion of 7.1 ± 2.6%. During the cardiac cycle, the left ventricle outflow tract expands, reaching its maximum surface at the end of diastole, followed by the aortic annulus, the Valsalva sinuses and the sinotubular junction. The aorta changes from a clover-shaped cone during diastole to more cylindrical shape during systole. Compared to the 3D measurements, the analysis of the virtual basal ring significantly underestimates the annulus area, perimeter, and mean diameter., Conclusions: 4D morphometric analysis enables to have a precise and reproducible evaluation of the aortic annulus. The aortic annulus and root are deformable structures that undergo a unique expansion sequence during the cardiac cycle which should be considered for procedural planning., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.) more...

Apicomplexan parasites possess specialized secretory organelles called rhoptries, micronemes, and dense granules that play a vital role in host infection. In this study, we demonstrate that TgREMIND, a protein found in Toxoplasma gondii, is necessary for the biogenesis of rhoptries and dense granules. TgREMIND contains a Fes-CIP4 homology-Bin/Amphiphysin/Rvs (F-BAR) domain, which binds to membrane phospholipids, as well as a novel uncharacterized domain that we have named REMIND (regulator of membrane-interacting domain). Both the F-BAR domain and the REMIND are crucial for TgREMIND functions. When TgREMIND is depleted, there is a significant decrease in the abundance of dense granules and abnormal transparency of rhoptries, leading to a reduction in protein secretion from these organelles. The absence of TgREMIND inhibits host invasion and parasite dissemination, demonstrating that TgREMIND is essential for the proper function of critical secretory organelles required for successful infection by Toxoplasma., Competing Interests: Declaration of interests The authors declare that they have no competing financial interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.) more...

Background: Coronary artery calcium score (CACS) refines the cardiovascular disease (CVD) risk prediction in patients with Type-2 diabetes (T2D). We aimed to identify the determinants for high CACS in CVD-free patients with T2D., Methods: We studied 796 patients with T2D with CACS measured in three centers: two in continental France and a third in the Reunion Island. To predict a CACS ≥ 100, we derived a risk score in patients in continental France, and validated it in those in the Reunion Island., Results: The distributions of CACS distributions were similar among patients in continental France and Reunion Island. The French-CAC100 score included 5 parameters (age, sex, diabetes duration, non-CV end-organ damage and presence of ≥ 2 other CVD risk factors), ranging from 0 to 22 points. Similar areas under the curves were found for the risk score in both settings (0.80 vs. 0.73, p = 0.10). A French-CAC100 score < 10 excluded the odds for CACS ≥ 100 and CACS ≥ 400 with negative predictive values of 90% and 97% respectively, avoiding 58% of CT-scans., Conclusion: Regardless of the geographic area, patients with T2D share similar risk factors for high CACS. The French-CAC100 score allows the identification of those at higher risk of elevated CACS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.) more...

There is a growing interest for complex in vitro environments that closely mimic the extracellular matrix and allow cells to grow in microenvironments that are closer to the one in vivo. Protein-based matrices and especially hydrogels can answer this need, thanks to their similarity with the cell microenvironment and their ease of customization. In this study, an experimental design was conducted to study the influence of synthesis parameters on the physical properties of gelatin methacryloyl (GelMA). Temperature, ratio of methacrylic anhydride over gelatin, rate of addition, and stirring speed of the reaction were studied using a Doehlert matrix. Their impact on the following parameters was analyzed: degree of substitution, mass swelling ratio, storage modulus (log(G')), and compression modulus. This study highlights that the most impactful parameter was the ratio of methacrylic anhydride over gelatin. Although, temperature affected the degree of substitution, and methacrylic anhydride addition flow rate impacted the gel's physical properties, namely, its storage modulus and compression modulus. Moreover, this experimental design proposed a theoretical model that described the variation of GelMA's physical characteristics as a function of synthesis conditions. more...

Lipid droplets (LDs) are the primary organelles of lipid storage, buffering energy fluctuations of the cell. They store neutral lipids in their core that is surrounded by a protein-decorated phospholipid monolayer. LDs arise from the endoplasmic reticulum (ER). The ER protein seipin, localizing at ER-LD junctions, controls LD nucleation and growth. However, how LD biogenesis is spatially and temporally coordinated remains elusive. Here, we show that the lipid transfer proteins ORP5 and ORP8 control LD biogenesis at mitochondria-associated ER membrane (MAM) subdomains, enriched in phosphatidic acid. We found that ORP5/8 regulates seipin recruitment to these MAM-LD contacts, and their loss impairs LD biogenesis. Importantly, the integrity of ER-mitochondria contact sites is crucial for ORP5/8 function in regulating seipin-mediated LD biogenesis. Our study uncovers an unprecedented ORP5/8 role in orchestrating LD biogenesis and maturation at MAMs and brings novel insights into the metabolic crosstalk between mitochondria, ER, and LDs at the membrane contact sites., (© 2022 Guyard et al.) more...

Legumes of the Medicago genus have a symbiotic relationship with the bacterium Sinorhizobium meliloti and develop root nodules housing large numbers of intracellular symbionts. Members of the n odule-specific c ysteine- r ich peptide (NCR) family induce the endosymbionts into a terminal differentiated state. Individual cationic NCRs are antimicrobial peptides that have the capacity to kill the symbiont, but the nodule cell environment prevents killing. Moreover, the bacterial broad-specificity peptide uptake transporter BacA and exopolysaccharides contribute to protect the endosymbionts against the toxic activity of NCRs. Here, we show that other S. meliloti functions participate in the protection of the endosymbionts; these include an additional broad-specificity peptide uptake transporter encoded by the yejABEF genes and lipopolysaccharide modifications mediated by lpsB and lpxXL , as well as rpoH1 , encoding a stress sigma factor. Strains with mutations in these genes show a strain-specific increased sensitivity profile against a panel of NCRs and form nodules in which bacteroid differentiation is affected. The lpsB mutant nodule bacteria do not differentiate, the lpxXL and rpoH1 mutants form some seemingly fully differentiated bacteroids, although most of the nodule bacteria are undifferentiated, while the yejABEF mutants form hypertrophied but nitrogen-fixing bacteroids. The nodule bacteria of all the mutants have a strongly enhanced membrane permeability, which is dependent on the transport of NCRs to the endosymbionts. Our results suggest that S. meliloti relies on a suite of functions, including peptide transporters, the bacterial envelope structures, and stress response regulators, to resist the aggressive assault of NCR peptides in the nodule cells. IMPORTANCE The nitrogen-fixing symbiosis of legumes with rhizobium bacteria has a predominant ecological role in the nitrogen cycle and has the potential to provide the nitrogen required for plant growth in agriculture. The host plants allow the rhizobia to colonize specific symbiotic organs, the nodules, in large numbers in order to produce sufficient reduced nitrogen for the plants' needs. Some legumes, including Medicago spp., produce massively antimicrobial peptides to keep this large bacterial population in check. These peptides, known as NCRs, have the potential to kill the rhizobia, but in nodules, they rather inhibit the division of the bacteria, which maintain a high nitrogen-fixing activity. In this study, we show that the tempering of the antimicrobial activity of the NCR peptides in the Medicago symbiont Sinorhizobium meliloti is multifactorial and requires the YejABEF peptide transporter, the lipopolysaccharide outer membrane, and the stress response regulator RpoH1. more...

Intellectual disability in Duchenne muscular dystrophy has been associated with the loss of dystrophin-protein 71, Dp71, the main dystrophin-gene product in the adult brain. Dp71 shows major expression in perivascular macroglial endfeet, suggesting that dysfunctional glial mechanisms contribute to cognitive impairments. In the present study, we investigated the molecular alterations induced by a selective loss of Dp71 in mice, using semi-quantitative immunogold analyses in electron microscopy and immunofluorescence confocal analyses in brain sections and purified gliovascular units. In macroglial pericapillary endfeet of the cerebellum and hippocampus, we found a drastic reduction (70%) of the polarized distribution of aquaporin-4 (AQP4) channels, a 50% reduction of β-dystroglycan, and a complete loss of α1-syntrophin. Interestingly, in the hippocampus and cortex, these effects were not homogeneous: AQP4 and AQP4ex isoforms were mostly lost around capillaries but preserved in large vessels corresponding to pial arteries, penetrating cortical arterioles, and arterioles of the hippocampal fissure, indicating the presence of Dp71-independent pools of AQP4 in these vascular structures. In conclusion, the depletion of Dp71 strongly alters the distribution of AQP4 selectively in macroglial perivascular endfeet surrounding capillaries. This effect likely affects water homeostasis and blood-brain barrier functions and may thus contribute to the synaptic and cognitive defects associated with Dp71 deficiency., (© 2020 Wiley Periodicals LLC.) more...

Nemaline myopathy type 6 (NEM6), KBTBD13-related congenital myopathy is caused by mutated KBTBD13 protein that interacts improperly with thin filaments/actin, provoking impaired muscle-relaxation kinetics. We describe muscle morphology in 18 Dutch NEM6 patients and correlate it with clinical phenotype and pathophysiological mechanisms. Rods were found in in 85% of biopsies by light microscopy, and 89% by electron microscopy. A peculiar ring disposition of rods resulting in ring-rods fiber was observed. Cores were found in 79% of NEM6 biopsies by light microscopy, and 83% by electron microscopy. Electron microscopy also disclosed granulofilamentous protein material in 9 biopsies. Fiber type 1 predominance and prominent nuclear internalization were found. Rods were immunoreactive for α-actinin and myotilin. Areas surrounding the rods showed titin overexpression suggesting derangement of the surrounding sarcomeres. NEM6 myopathology hallmarks are prominent cores, rods including ring-rods fibers, nuclear clumps, and granulofilamentous protein material. This material might represent the histopathologic epiphenomenon of altered interaction between mutated KBTBD13 protein and thin filaments. We claim to classify KBTBD13-related congenital myopathy as rod-core myopathy., (© 2021 American Association of Neuropathologists, Inc. All rights reserved.) more...

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. more...

The endo-lysosome system is involved in endocytosis, protein sorting, and degradation as well as autophagy. Numerous toxins and pathogens exploit this system to enter host cells and exert their deleterious effects. Modulation of host endo-lysosome pathway may restrict multiple toxins intoxication as well as pathogen infection. ABMA, selected from a high-throughput screening against the cytotoxicity of ricin toxin, exhibits a broad-spectrum antitoxin and antipathogen activity. Here, we show that ABMA selectively retains endocytosed protein and toxin to late endosomes and thus delaying their intracellular trafficking. It also impairs the autophagic flux by excessive fusion of late endosomes and autophagosomes. Its exclusive action on late endosomes and corresponding consequences on the endo-lysosomal pathway and autophagic flux are distinct from known inhibitors such as bafilomycin A1, EGA, or chloroquine. Hence, besides being a broad-spectrum inhibitor of endocytosed toxins and pathogens, ABMA may serve as a molecular tool to dissect endo-lysosome system-related cellular physiology and mechanisms of pathogenesis., (© 2020 Federation of European Biochemical Societies.) more...

Cardiac involvement in systemic light chain (AL) amyloidosis carries a poor prognosis mainly through involvement of the left ventricular (LV) myocardium. Despite its limitations, two-dimensional transthoracic echocardiography (2D-TTE) remains the main tool used for the assessment of LV systolic function in AL patients. We hypothesize that 3D-TTE coupled with speckle tracking imaging allows earlier detection of LV systolic dysfunction than 2D-TTE in AL amyloidosis. We prospectively studied 71 subjects including 58 patients with confirmed AL amyloidosis (mean age 66 ± 10 years, 60% male) and 21 healthy control (mean age 64 ± 7 years, 48% male) from 2011 to 2014 at the University Hospital of Limoges. The AL patients were divided into three groups according to Mayo Clinic (MC) staging and all subjects underwent 2D-TTE and 3D-TTE at the same setting. Using 2D-TTE, there was no significant difference in LV ejection fraction (EF) between the groups [LVEF = 63 ± 7% (control), 59 ± 6% (MC stage I), 60 ± 8% (MC stage II) and 57 ± 14% (MC stage III) (p = 0.24)]. In contrast, 3D-TTE demonstrated significantly worse LV systolic function in stage II and III patients using 3D-LVEF [MC II and III 45 ± 8% and 39 ± 12% vs. control 53 ± 8% (p < 0.0001)], global longitudinal strain (GLS) [MC II and III - 11 ± 4% and - 8 ± 3% vs. control - 15 ± 3% (p < 0.0001)] and global radial strain (GRS) [MC II and III 14 ± 9% and 10 ± 8% vs. control 25 ± 10% (p < 0.0001)]. Furthermore, MC III patients had significantly worse global circumferential strain and area tracking [- 17 ± 6% and - 25 ± 8% vs. - 24 ± 7% and - 36 ± 7% for control (p < 0.0001)]. Additionally, MC I had significantly better 3D GLS, GRS and global strain (- 15 ± 3%, 25 ± 10% and 28 ± 12%) than MC II (- 11 ± 4%, 14 ± 9% and 16 ± 10%) and MC III patients (- 8 ± 3%, 10 ± 8% and 12 ± 8%), respectively. Despite an apparently preserved LVEF by 2D-TTE, AL patients in MC stage II and III demonstrate evidence of LV systolic dysfunction by 3D imaging using LVEF and strain analysis. Worse LV involvement by AL amyloidosis was associated with more impaired 3D-TTE LV systolic parameters. more...

Background: Fabry cardiomyopathy (FC) and light-chain amyloid cardiomyopathy (AL) present with concentric left ventricular (LV) hypertrophy/remodeling and diastolic rather than systolic dysfunction. Direct comparisons are difficult due to rarity and confounded by variability of LV thickness., Aims: To compare LV diastolic and systolic properties between patients with FC and AL in a cohort matched for interventricular septal thickness (IVS)., Methods: A two-center echocardiographic analysis was performed, comprising 118 patients with IVS ≥12 mm (FC and AL 59 patients each) matched by IVS., Results: Fabry cardiomyopathy patients had larger LV end-diastolic diameter (47.7 [44.0-50.9] vs 45.0 [41.5-49.0] mm, P = 0.002), better LV ejection fraction (EF 68.7 [63.4-74.0] vs 63.0 [54.0-70.0]%, P = 0.001) and midwall fractional shortening (midFS 14.8 [13.0-16.1] vs 12.1 [8.9-15.0]%, P = 0.006). LV EF <40% was rare in both (2% vs 7%, P = 0.17). AL patients expressed higher LV diastolic dysfunction grade (III in 26% vs 4%, II in 21% vs 12% and I in 54% vs 84%, P = 0.004), with higher E/e' ratio (13.6 [10.2-18.8] vs 9.8 [7.5-12.3], P < 0.0001). Average E/e' ratio and midFS were significantly associated with NYHA severity in both groups (P < 0.05 for all)., Conclusions: Matched AL patients had worse LV diastolic function than FC, driven by E/e'. Significant LV systolic dysfunction was rare overall. MidFS and E/e' were associated with heart failure severity in both groups., (© 2018 Wiley Periodicals, Inc.) more...

The recent discovery of cyanobacteria forming intracellular amorphous calcium carbonate (ACC) has challenged the former paradigm suggesting that cyanobacteria-mediated carbonatogenesis was exclusively extracellular. Yet, the mechanisms of intracellular biomineralization in cyanobacteria and in particular whether this takes place within an intracellular microcompartment, remain poorly understood. Here, we analyzed six cyanobacterial strains forming intracellular ACC by transmission electron microscopy. We tested two different approaches to preserve as well as possible the intracellular ACC inclusions: (i) freeze-substitution followed by epoxy embedding and room-temperature ultramicrotomy and (ii) high-pressure freezing followed by cryo-ultramicrotomy, usually referred to as cryo-electron microscopy of vitreous sections (CEMOVIS). We observed that the first method preserved ACC well in 500-nm-thick sections but not in 70-nm-thick sections. However, cell ultrastructures were difficult to clearly observe in the 500-nm-thick sections. In contrast, CEMOVIS provided a high preservation quality of bacterial ultrastructures, including the intracellular ACC inclusions in 50-nm-thick sections. ACC inclusions displayed different textures, suggesting varying brittleness, possibly resulting from different hydration levels. Moreover, an electron dense envelope of ∼2.5 nm was systematically observed around ACC granules in all studied cyanobacterial strains. This envelope may be composed of a protein shell or a lipid monolayer, but not a lipid bilayer as usually observed in other bacteria forming intracellular minerals. Overall, this study evidenced that ACC inclusions formed and were stabilized within a previously unidentified bacterial microcompartment in some species of cyanobacteria. more...

Background: Systemic light chain amyloidosis (AL) is characterized by the extracellular deposition of amyloid fibrils. Transthoracic echocardiography is the modality of choice to assess cardiac function in patients with AL. Whereas left ventricular (LV) function has been well studied in this patient population, data regarding the value of left atrial (LA) function in AL patients are lacking. In this study, we aim to examine the impact of LA volumes and function on survival in AL patients as assessed by real-time 3D echocardiography., Methods: A total of 77 patients (67±10 years, 60% men) with confirmed AL and 39 healthy controls were included. All standard 2D echocardiographic and 3D-LA parameters were obtained., Results: Fourteen patients (18%) were in Mayo Clinic (MC) stage I, 30 (39%) in stage II, and 33 (43%) in stage III at initial evaluation. There was no significant difference among the MC stages groups in terms of age, gender, or cardiovascular risk factors. As compared to patients in MC II and MC I, those in MC III had significantly larger indexed 3D-LA volumes (MCIII: 46±15mL/m 2 , MC II: 38±12mL/m 2 , and MC I: 23±9mL/m 2 , p<0.0001), lower 3D-LA total emptying fraction (3D-tLAEF) (21±13% vs. 31±15% vs. 43±7%, respectively, p<0.0001), and worse 3D peak atrial longitudinal strain (3D-PALS) (11±9% vs. 18±13% vs. 20±7%, respectively, p=0.007). Two-year survival was significantly lower in patients with 3D-tLAEF <+34% (p=0.003) and in those with 3D-PALS <+14% (p=0.034). Both parameters provided incremental prognostic value over maximal LA volume in multivariate analysis., Conclusion: Functional LA parameters are progressively altered in AL patients according to the MC stage. A decrease in 3D-PALS is associated with worse outcome, independently of LA volume., (Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.) more...

Intracellular pathogenic microorganisms and toxins exploit host cell mechanisms to enter, exert their deleterious effects as well as hijack host nutrition for their development. A potential approach to treat multiple pathogen infections and that should not induce drug resistance is the use of small molecules that target host components. We identified the compound 1-adamantyl (5-bromo-2-methoxybenzyl) amine (ABMA) from a cell-based high throughput screening for its capacity to protect human cells and mice against ricin toxin without toxicity. This compound efficiently protects cells against various toxins and pathogens including viruses, intracellular bacteria and parasite. ABMA provokes Rab7-positive late endosomal compartment accumulation in mammalian cells without affecting other organelles (early endosomes, lysosomes, the Golgi apparatus, the endoplasmic reticulum or the nucleus). As the mechanism of action of ABMA is restricted to host-endosomal compartments, it reduces cell infection by pathogens that depend on this pathway to invade cells. ABMA may represent a novel class of broad-spectrum compounds with therapeutic potential against diverse severe infectious diseases. more...

Aims: The prognostic impact of elevated pulmonary arterial pressure (PAP) remains controversial in aortic stenosis (AS) and few studies focused on patients with preserved left ventricular ejection fraction (LVEF). We aimed to investigate the impact of pulmonary hypertension (PH), invasively derived, on survival in severe AS with preserved LVEF., Methods and Results: Between 2000 and 2010, 749 patients (74 ± 8 years, 57% males) with preserved LVEF and severe AS without other valvular heart disease underwent cardiac catheterization. PH was defined as mean PAP > 25 mmHg. The mean follow-up was 4.6 ± 3.0 years. Overall, 32% (n = 241) of patients had PH. Surgical aortic valve replacement (SAVR) was performed in 91% of patients with 4.5% of 30-day mortality rate, significantly higher in patients with PH than without PH (7.5 vs. 3.5%, p = 0.014). In logistic regression, PH was an independent predictor of increased 30-day mortality (odds-ratio = 2.2, p = 0.04). Overall long-term survival was significantly reduced in patients with PH as compared to those without (10-year: 52 ± 5 vs. 68 ± 3%, p < 0.0001). Likewise, focusing on patients with SAVR showed significant reduced survival in those with PH (10-year: 57 ± 5 vs. 72 ± 3%, p < 0.0001). In multivariate analysis, after adjustment for relevant cofactors, PH was an independent predictor of mortality (hazard ratio = 1.5, p = 0.009). Using quartiles of mean PAP, only patients with most elevated values (Q4: mean PAP: 27-67mmHg) had significantly reduced survival, as compared to other quartiles (all p < 0.0001)., Conclusion: In patients with severe AS and preserved LVEF, PH is an independent predictor of 30-day and long-term mortality patients. Nevertheless, only severely elevated PAP seems associated with reduced survival. more...

Recently, a number of diverse correlative light and electron microscopy (CLEM) protocols have been developed for several model organisms. However, these CLEM methods have largely bypassed plant cell research, with most protocols having little application to plants. Using autophagosome identification as a biological background, we propose and compare two CLEM protocols that can be performed in most plant research laboratories, providing a good compromise that preserves fluorescent signals as well as ultrastructural features. These protocols are based on either the adaptation of a high pressure fixation/GMA acrylic resin embedding method, or on the Tokuyasu approach. Both protocols suitably preserved GFP fluorescence while allowing the observation of cell ultrastructure in plants. Finally, the advantages and disadvantages of these protocols are discussed in the context of multiscale imaging of plant cells., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.) more...

Background: Left heart valve thickening (LVT) was described in patients with light-chain amyloidosis (AL). This phenomenon reflects likely infiltration of the valve by amyloid proteins. However, the prevalence of LVT and its prognostic value have not been investigated in patients with AL., Methods and Results: Comprehensive transthoracic echocardiography was performed at baseline in 150 patients [median age 68 (33-87) years; 59% male] with confirmed AL. The presence of abnormal mitral and/or aortic valve thickening (>3 mm) was assessed in all included patients. Overall, 42% had LVT at the time of diagnosis. Compared to patients without LVT, those with LVT were older and had a more advanced NYHA functional class (63% in patients with NYHA III-IV vs. 33% in NYHA I-II, p < 0.001). They also had higher left ventricular (LV) wall thickness and mass, larger left atrium, higher mitral annulus E/E' ratio and systolic pulmonary artery pressures, and lower LV ejection fraction (all p < 0.05). Patients with more advanced Mayo Clinic stage had a higher incidence of LVT: 58% in stage III vs. 45% in stage II and 5% in stage I (p < 0.001). During a median follow-up of 2 years, 79 deaths occurred. The presence of LVT was significantly associated with reduced 5-year survival (32 ± 7 vs. 64 ± 6%). In multivariate analysis, after adjusting for age, gender, NYHA functional class, and LV ejection fraction, LVT remained significantly associated with higher all-cause mortality (hazard ratio 1.90, 95% CI 1.10-3.34, p = 0.02)., Conclusion: Left heart valve thickening is common in patients with AL and is associated with worse functional class, LV systolic and diastolic function, and more advanced stage of the disease. In addition, LVT appears to be a powerful marker of all-cause mortality. more...

Background: Cardiac involvement in systemic light-chain amyloidosis (AL) imparts an adverse impact on outcome. The left atrium (LA), by virtue of its anatomical location and muscular wall, is commonly affected by the amyloid process. Although LA infiltration by amyloid fibrils leads to a reduction in its pump function, the infiltration of the left ventricular (LV) myocardium results in diastolic dysfunction with subsequent increase in filling pressures and LA enlargement. Even though left atrial volume (LAV) is an independent prognostic marker in many cardiomyopathies, its value in amyloid heart disease remains to be determined. In addition, few data are available as to the prognostic value of LA function in systemic AL. Using cardiac magnetic resonance (CMR), the current study aims to assess the prognostic significance of the maximal LAV and total LA emptying fraction (LAEF) in patients with AL., Methods and Results: Fifty-four consecutive patients (age 66 ± 10 years, 59% males) with confirmed systemic AL and mean LV ejection fraction of 60 ± 12% underwent CMR. As compared with patients with no or minimal cardiac involvement (Mayo Clinic [MC] stage I), those at moderate and high risk (MC stages II and III) had significantly larger indexed maximal LAV (36 ± 15 vs. 46 ± 13 vs. 52 ± 19 mL/m(2), P = 0.03) and indexed minimal LAV (20 ± 6 vs. 34 ± 11 vs. 44 ± 17 mL/m(2), P < 0.001), lower LAEF (42 ± 9 vs. 26 ± 13 vs. 16 ± 9%, P < 0.0001) but similar LVEF. Furthermore, myocardial late gadolinium enhancement (LGE) was more frequent and significantly associated with lower LAEF. LAEF was also significantly lower in symptomatic (NHYA ≥ II, 22 ± 14%) as compared with asymptomatic patients (NYHA class I, 33 ± 13%, P = 0.006). Two-year survival rate was lower in patients with LAEF ≤ 16% as compared with those with LAEF > 16% (37 ± 11 vs. 94 ± 4%, P = 0.001). In multivariate analysis, lower LAEF remained independently associated with a higher risk of 2-year mortality (HR = 1.08 per 1% decrease, 95% CI: 1.02-1.15, P = 0.003)., Conclusion: In patients with systemic AL, LAEF as assessed by CMR is associated with NYHA functional class, MC stage, myocardial LGE and 2-year mortality., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.) more...

Aims: Previous studies using echocardiography suggested that a low flow (LF) defined as an indexed stroke volume (SVi) <35 mL/m(2) may be an important determinant of outcome in patients with severe aortic stenosis (AS). We sought to assess the prognostic importance of stroke volume derived from invasive data. The aim of this study was to determine the impact of LF, purposely derived from cardiac catheterisation data, on outcome of patients with severe AS and preserved LVEF., Methods: Between 2000 and 2010, 768 patients with preserved LVEF (>50%) and severe AS (valve area ≤1 cm(2)) without other valvular heart disease underwent cardiac catheterisation. The long-term overall mortality was assessed as the primary end-point., Results: Mean age was 74±8 years, 58% were men, 46% had coronary artery disease and mean LVEF was 72±10%. Low SVi was found in 27% (n=210) of patients with AS. As compared with patients with normal SVi, those with low SVi were significantly older (p<0.0001) with higher rate of atrial fibrillation (p<0.0001). Additionally, they had lower LVEF (p=0.046), aortic valve area (p<0.0001), mean pressure gradient (p<0.0001), systemic arterial compliance (p<0.0001) and higher systemic vascular resistances (p<0.0001). Eight-year survival was significantly reduced in patients with low SVi as compared with those with normal SVi (51±5% vs 67±3%; p<0.0001). After adjustment for all other risk factors, reduced SVi was independently associated with long-term mortality (HR=1.45, 95% CI 1.1 to 2.1; p=0.048)., Conclusions: In patients with severe AS and preserved LVEF, LF, as assessed using cardiac catheterisation is frequent, and is an independent predictor of mortality. Consequently, the measurement of SVi should be systematically included in the assessment of these patients., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.) more...

Introduction: Global left ventricular (LV) afterload as assessed by valvulo-arterial impedance (Zva), may be an independent predictor of mortality in patients with severe aortic stenosis (AS) and preserved LV ejection fraction (LVEF). However, its quantification using echocardiography may be subject to error measurement. We aimed to determine the prevalence and impact on long-term survival of high Zva, purposely measured by cardiac catheterization., Methods and Results: 676 patients with preserved LVEF and severe AS without other valvular heart diseases underwent cardiac catheterization. Zva was derived from catheterization and calculated as follows: mean aortic gradient+systolic blood pressure/indexed LV stroke volume. Zva was considered high when >5mmHg/mL/m(2) based on previous studies. Overall, high Zva was found in 42% of all AS patients. Four-year survival and 8-year survival were significantly reduced in patients with high Zva (74±3% and 57±4%) as compared to those with low Zva (85±2% and 74±3%; p=0.002). After adjustment for all other risk factors, Zva was independently associated with reduced long-term survival (hazard ratio [HR]=1.47 95% CI: 1.04-2.09; p=0.029). Of interest, high Zva remained associated with reduced survival as compared to low Zva, in patients with normal LV stroke volume, but was no longer significant in low flow patients (p=0.98)., Conclusion: High Zva, estimated invasively in our study, is frequent in patients with severe AS, and appears as a robust and independent predictor of survival. Zva should be used as an additional parameter for risk stratification of severe AS, more particularly in patients with normal flow., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.) more...

Background: Patients with severe aortic stenosis (AS) and paradoxical low flow (PLF) have worse outcome compared with those with normal flow. Furthermore, prosthesis-patient mismatch (PPM) after aortic valve replacement is a predictor of reduced survival. However, the prevalence and prognostic impact of PPM in patients with PLF-AS are unknown. We aimed to analyze the prevalence and long-term survival of PPM in patients with PLF-AS., Methods and Results: Between 2000 and 2010, 677 patients with severe AS, preserved left ventricular ejection fraction, and aortic valve replacement were included (74±8 years; 42% women; aortic valve area, 0.69±0.16 cm(2)). A PLF (indexed stroke volume ≤35 mL/m(2)) was found in 26%, and after aortic valve replacement, 54% of patients had PPM, defined as an indexed effective orifice area ≤0.85 cm(2)/m(2). The combined presence of PLF and PPM was found in 15%. Compared with patients with noPLF/noPPM, those with PLF/PPM were significantly older, with more comorbidities. They also received smaller and biological bioprosthesis more often (all P<0.01). Although early mortality was not significantly different between groups, the 10-year survival rate was significantly reduced in case of PLF/PPM compared with noPLF/noPPM (38±9% versus 70±5%; P=0.002), even after multivariable adjustment (hazard ratio, 2.58; 95% confidence interval, 1.5-4.45; P=0.0007)., Conclusions: In this large catheterization-based study, the coexistence of PLF-AS before surgery and PPM after surgery is associated with the poorest outcome., (© 2014 American Heart Association, Inc.) more...

The formation of the autophagic vesicles requires the recruitment of ubiquitin-like Atg8 proteins to the membrane of nascent autophagosomes. Seven Atg8 homologs are present in mammals, split into the LC3 and the GABARAP/GATE-16 families, whose respective functions are unknown. Using Caenorhabditis elegans, we investigated the functions of the GABARAP and the LC3 homologs, LGG-1 and LGG-2, in autophagosome biogenesis. Both LGG-1 and LGG-2 localize to the autophagosomes but display partially overlapping patterns. During allophagy, a developmentally stereotyped autophagic flux, LGG-1 acts upstream of LGG-2 to allow its localization to autophagosomes. LGG-2 controls the maturation of LGG-1-positive autophagosomes and facilitates the tethering with the lysosomes through a direct interaction with the VPS-39 HOPS complex subunit. Genetic analyses sustain a sequential implication of LGG-1, LGG-2, RAB-7, and HOPS complex to generate autolysosomes. The duplications of Atg8 in metazoans thus allowed the acquisition of specialized functions for autophagosome maturation., (Copyright © 2014 Elsevier Inc. All rights reserved.) more...

In internal membrane-containing viruses, a lipid vesicle enclosed by the icosahedral capsid protects the genome. It has been postulated that this internal membrane is the genome delivery device of the virus. Viruses built with this architectural principle infect hosts in all three domains of cellular life. Here, using a combination of electron microscopy techniques, we investigate bacteriophage PRD1, the best understood model for such viruses, to unveil the mechanism behind the genome translocation across the cell envelope. To deliver its double-stranded DNA, the icosahedral protein-rich virus membrane transforms into a tubular structure protruding from one of the 12 vertices of the capsid. We suggest that this viral nanotube exits from the same vertex used for DNA packaging, which is biochemically distinct from the other 11. The tube crosses the capsid through an aperture corresponding to the loss of the peripentonal P3 major capsid protein trimers, penton protein P31 and membrane protein P16. The remodeling of the internal viral membrane is nucleated by changes in osmolarity and loss of capsid-membrane interactions as consequence of the de-capping of the vertices. This engages the polymerization of the tail tube, which is structured by membrane-associated proteins. We have observed that the proteo-lipidic tube in vivo can pierce the gram-negative bacterial cell envelope allowing the viral genome to be shuttled to the host cell. The internal diameter of the tube allows one double-stranded DNA chain to be translocated. We conclude that the assembly principles of the viral tunneling nanotube take advantage of proteo-lipid interactions that confer to the tail tube elastic, mechanical and functional properties employed also in other protein-membrane systems., Competing Interests: The authors have declared that no competing interests exist. more...

Capsids of double-stranded DNA (dsDNA) bacteriophages initially assemble into compact procapsids, which undergo expansion upon the genome packaging. This shell remodeling results from a structural rearrangement of head protein subunits. It is a critical step in the capsid maturation pathway that yields final particles capable to withstand the huge internal pressure generated by the packed DNA. Here, we report on the expansion process of the large capsid (T=13) of bacteriophage T5. We purified the intermediate prohead II form, which is competent for packaging the 121-kbp dsDNA genome, and we investigated its morphology and dimensions using cryo-electron microscopy and small-angle X-ray scattering. Decreasing the pH or the ionic strength triggers expansion of prohead II, converting them into thinner and more faceted capsids isomorphous to the mature virion particles. At low pH, prohead II expansion is a highly cooperative process lacking any detectable intermediate. This two-state reorganization of the capsid lattice per se leads to a remarkable stabilization of the particle. The melting temperature of expanded T5 capsid is virtually identical with that of more complex shells that are reinforced by inter-subunit cross-linking (HK97) or by additional cementing proteins (T4). The T5 capsid with its "simple" two-state conversion thus appears to be a very attractive model for investigating the mechanism of the large-scale allosteric transition that takes place upon the genome packaging of dsDNA bacteriophages., (Copyright © 2013 Elsevier Ltd. All rights reserved.) more...

Sphingolipids play an essential role in the functioning of the secretory pathway in eukaryotic organisms. Their importance in the functional organization of plant cells has not been studied in any detail before. The sphingolipid synthesis inhibitor fumonisin B1 (FB1), a mycotoxin acting as a specific inhibitor of ceramide synthase, was tested for its effects on cell growth, cell polarity, cell shape, cell cycle and on the ultrastructure of BY2 cells. We used cell lines expressing different GFP-tagged markers for plant cell compartments, as well as a Golgi marker fused to the photoconvertible protein Kaede. Light and electron microscopy, combined with flow cytometry, were applied to analyse the morphodynamics and architecture of compartments of the secretory pathway. The results indicate that FB1 treatment had severe effects on cell growth and cell shape, and induced a delay in cell division processes. The cell changes were accompanied by the formation of the endoplasmic reticulum (ER)-derived tubular aggregates (FB1-induced compartments), together with an inhibition of cargo transport from the ER to the Golgi apparatus. A change in polar localization of the auxin transporter PIN1 was also observed, but endocytic processes were little affected. Electron microscopy studies confirmed that molecular FB1 targets were distinct from brefeldin A (BFA) targets. We propose that the reported effects of inhibition of ceramide biosynthesis reflect the importance of sphingolipids during cell growth and establishment of cell polarity in higher plant cells, notably through their contribution to the functional organization of the ER or its differentiation into distinct compartments., (© 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.) more...