Treatment of Deep Vein Thrombosis with Continuous IV Infusion of LMWH: A Retrospective Study in 32 Children

Thirty-two consecutive children aged 0–18 years with VTE treated with LMWH administered as a continuous infusion (CI) were identified at the Children's University Hospital Brno. The treatment led to at least partial resolution of the thrombus within two weeks in 85% of patients. There were no adverse events or increased bleeding reported in any patients. No recurrences were observed during a followup period of 6 months. Although continuous infusion should not replace subcutaneous (SC) administration of LMWH, CI appeared to be safe and efficient and may provide an alternate method of administering LMWH in a subset of the paediatric population where SC administration may not be feasible. Further prospective studies are needed to support the promising findings of our pilot clinical observation

Aryl Hydrocarbon Receptor-Dependent Metabolism Plays a Significant Role in Estrogen-Like Effects of Polycyclic Aromatic Hydrocarbons on Cell Proliferation

Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental contaminants that interact in a complex manner with both the aryl hydrocarbon receptor (AhR) and estrogen receptors (ER). Their potential endocrine-disrupting activities may depend on both inhibitory AhR-ER cross-talk and on AhR-dependent metabolic production of estrogenic PAH metabolites. Here, we analyzed the impact of AhR on estrogen-like effects of PAHs, such as benzo[a]pyrene (BaP), in particular, on control of cell cycle progression/cell proliferation. Using AhR knockout variant of estrogen-sensitive human breast cancer MCF-7 cells (MCF-7 AhRKO cells), we observed that the AhR-dependent control of cytochrome P450 family 1 (CYP1) expression played a major role in formation of estrogenic BaP metabolites, most notably 3-OH-BaP, which contributed to the ER-dependent induction of cell cycle progression/cell proliferation. Both BaP metabolism and the BaP-induced S-phase transition/cell proliferation were inhibited in MCF-7 AhRKO cells, whereas these cells remained sensitive towards both endogenous estrogen 17β-estradiol or hydroxylated BaP metabolites. BaP was found to increase the activity of ER-dependent luciferase reporter gene in wild-type MCF-7 cells; however, unlike its hydroxylated metabolite, BaP failed to stimulate luciferase activity in MCF-7 AhRKO cells. Similarly, estrogen-like effects of other known estrogenic PAHs, such as benz[a]anthracene or 3-methylcholanthrene, were diminished in MCF-7 AhRKO cells. Ectopic expression of human CYP1A1 and CYP1B1 enzymes partly restored both BaP metabolism and its effects on cell proliferation. Taken together, our data suggest that the AhR-dependent metabolism of PAHs contributes significantly to the impact of PAHs on cell proliferation in estrogen-sensitive cells

Safety of dabigatran etexilate for the secondary prevention of venous thromboembolism in children

This open-label, single-arm, prospective cohort trial is the first phase 3 safety study to describe outcomes in children treated with dabigatran etexilate for secondary venous thromboembolism (VTE) prevention. Eligible children aged 12 to 3 months to 3 months to <18 years with persistent VTE risk factor(s)

CEBPE-Mutant Specific Granule Deficiency Correlates With Aberrant Granule Organization and Substantial Proteome Alterations in Neutrophils

Specific granule deficiency (SGD) is a rare disorder characterized by abnormal neutrophils evidenced by reduced granules, absence of granule proteins, and atypical bilobed nuclei. Mutations in CCAAT/enhancer-binding protein- (CEBPE) are one molecular etiology of the disease. Although C/EBP has been studied extensively, the impact of CEBPE mutations on neutrophil biology remains elusive. Here, we identified two SGD patients bearing a previously described heterozygous mutation (p.Val218Ala) in CEBPE. We took this rare opportunity to characterize SGD neutrophils in terms of granule distribution and protein content. Granules of patient neutrophils were clustered and polarized, suggesting that not only absence of specific granules but also defects affecting other granules contribute to the phenotype. Our analysis showed that remaining granules displayed mixed protein content and lacked several glycoepitopes. To further elucidate the impact of mutant CEBPE, we performed detailed proteomic analysis of SGD neutrophils. Beside an absence of several granule proteins in patient cells, we observed increased expression of members of the linker of nucleoskeleton and cytoskeleton complex (nesprin-2, vimentin, and lamin-B2), which control nuclear shape. This suggests that absence of these proteins in healthy individuals might be responsible for segmented shapes of neutrophilic nuclei. We further show that the heterozygous mutation p.Val218Ala in CEBPE causes SGD through prevention of nuclear localization of the protein product. In conclusion, we uncover that absence of nuclear C/EBP impacts on spatiotemporal expression and subsequent distribution of several granule proteins and further on expression of proteins controlling nuclear shape.(VLID)470191

The reliability of bone marrow cytology as response criterion in metastatic neuroblastoma

Background The quantitative assessment of neuroblastoma cell content in bone marrow aspirates for response evaluation has been introduced recently. Data on the concordance of interobserver reports are lacking so far. Methods Investigators of seven European countries representing national reference or large oncological centers convened in 2016. They agreed to quantitatively assess routine bone marrow smears of the participating institutions and to discuss the discrepant results in joint meetings. Results From 2017 through 2019, three cytology rounds with 24, 28, and 28 bone marrow samples were run evaluating the representativity of the smears (yes/[restricted]/no) and the presence of tumor cells (yes/no and %). The comparison of the reports using kappa (Fleiss) and alpha (Krippendorff) statistics demonstrated no robust reliabilities. The agreement on the representativity was moderate to poor, on the presence of tumor cells moderate to good, and on the percentage of tumor cells slight to moderate. Though the value of cytology is unquestioned to detect even tiny metastatic cells in bone marrow, the investigators unanimously agreed that a reliable quantification of the tumor cell content in bone marrow smears is unrealistic. For the key issue of representativity, a new practical definition was developed. Conclusion For any work with bone marrow aspirates, the representativity of the material is of paramount importance. A practical definition is proposed. A reliable quantitative cytological assessment of tumor cell content in bone marrow aspirates is not feasible in metastatic neuroblastoma. Therefore, its use as response criterion should be reconsidered

CEBPE-Mutant Specific Granule Deficiency Correlates With Aberrant Granule Organization and Substantial Proteome Alterations in Neutrophils

Specific granule deficiency (SGD) is a rare disorder characterized by abnormal neutrophils evidenced by reduced granules, absence of granule proteins, and atypical bilobed nuclei. Mutations in CCAAT/enhancer-binding protein-ε (CEBPE) are one molecular etiology of the disease. Although C/EBPε has been studied extensively, the impact of CEBPE mutations on neutrophil biology remains elusive. Here, we identified two SGD patients bearing a previously described heterozygous mutation (p.Val218Ala) in CEBPE. We took this rare opportunity to characterize SGD neutrophils in terms of granule distribution and protein content. Granules of patient neutrophils were clustered and polarized, suggesting that not only absence of specific granules but also defects affecting other granules contribute to the phenotype. Our analysis showed that remaining granules displayed mixed protein content and lacked several glycoepitopes. To further elucidate the impact of mutant CEBPE, we performed detailed proteomic analysis of SGD neutrophils. Beside an absence of several granule proteins in patient cells, we observed increased expression of members of the linker of nucleoskeleton and cytoskeleton complex (nesprin-2, vimentin, and lamin-B2), which control nuclear shape. This suggests that absence of these proteins in healthy individuals might be responsible for segmented shapes of neutrophilic nuclei. We further show that the heterozygous mutation p.Val218Ala in CEBPE causes SGD through prevention of nuclear localization of the protein product. In conclusion, we uncover that absence of nuclear C/EBPε impacts on spatiotemporal expression and subsequent distribution of several granule proteins and further on expression of proteins controlling nuclear shape

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<p>Specific granule deficiency (SGD) is a rare disorder characterized by abnormal neutrophils evidenced by reduced granules, absence of granule proteins, and atypical bilobed nuclei. Mutations in CCAAT/enhancer-binding protein-ε (CEBPE) are one molecular etiology of the disease. Although C/EBPε has been studied extensively, the impact of CEBPE mutations on neutrophil biology remains elusive. Here, we identified two SGD patients bearing a previously described heterozygous mutation (p.Val218Ala) in CEBPE. We took this rare opportunity to characterize SGD neutrophils in terms of granule distribution and protein content. Granules of patient neutrophils were clustered and polarized, suggesting that not only absence of specific granules but also defects affecting other granules contribute to the phenotype. Our analysis showed that remaining granules displayed mixed protein content and lacked several glycoepitopes. To further elucidate the impact of mutant CEBPE, we performed detailed proteomic analysis of SGD neutrophils. Beside an absence of several granule proteins in patient cells, we observed increased expression of members of the linker of nucleoskeleton and cytoskeleton complex (nesprin-2, vimentin, and lamin-B2), which control nuclear shape. This suggests that absence of these proteins in healthy individuals might be responsible for segmented shapes of neutrophilic nuclei. We further show that the heterozygous mutation p.Val218Ala in CEBPE causes SGD through prevention of nuclear localization of the protein product. In conclusion, we uncover that absence of nuclear C/EBPε impacts on spatiotemporal expression and subsequent distribution of several granule proteins and further on expression of proteins controlling nuclear shape.</p

Vascular Remodeling of Clinically Used Patches and Decellularized Pericardial Matrices Recellularized with Autologous or Allogeneic Cells in a Porcine Carotid Artery Model

Background: Cardiovascular surgery is confronted by a lack of suitable materials for patch repair. Acellular animal tissues serve as an abundant source of promising biomaterials. The aim of our study was to explore the bio-integration of decellularized or recellularized pericardial matrices in vivo. Methods: Porcine (allograft) and ovine (heterograft, xenograft) pericardia were decellularized using 1% sodium dodecyl sulfate ((1) Allo-decel and (2) Xeno-decel). We used two cell types for pressure-stimulated recellularization in a bioreactor: autologous adipose tissue-derived stromal cells (ASCs) isolated from subcutaneous fat of pigs ((3) Allo-ASC and (4) Xeno-ASC) and allogeneic Wharton’s jelly mesenchymal stem cells (WJCs) ((5) Allo-WJC and (6) Xeno-WJC). These six experimental patches were implanted in porcine carotid arteries for one month. For comparison, we also implanted six types of control patches, namely, arterial or venous autografts, expanded polytetrafluoroethylene (ePTFE Propaten® Gore®), polyethylene terephthalate (PET Vascutek®), chemically stabilized bovine pericardium (XenoSure®), and detoxified porcine pericardium (BioIntegral® NoReact®). The grafts were evaluated through the use of flowmetry, angiography, and histological examination. Results: All grafts were well-integrated and patent with no signs of thrombosis, stenosis, or aneurysm. A histological analysis revealed that the arterial autograft resembled a native artery. All other control and experimental patches developed neo-adventitial inflammation (NAI) and neo-intimal hyperplasia (NIH), and the endothelial lining was present. NAI and NIH were most prominent on XenoSure® and Xeno-decel and least prominent on NoReact®. In xenografts, the degree of NIH developed in the following order: Xeno-decel > Xeno-ASC > Xeno-WJC. NAI and patch resorption increased in Allo-ASC and Xeno-ASC and decreased in Allo-WJC and Xeno-WJC. Conclusions: In our setting, pre-implant seeding with ASC or WJC had a modest impact on vascular patch remodeling. However, ASC increased the neo-adventitial inflammatory reaction and patch resorption, suggesting accelerated remodeling. WJC mitigated this response, as well as neo-intimal hyperplasia on xenografts, suggesting immunomodulatory properties