336 research outputs found

    Cellulose acetate in wound dressings formulations: potentialities and electrospinning capability

    Get PDF
    Série: IFMBE Proceedings, vol. 76Any open wound is a potential site for microorganisms’ invasion since their presence around us is inevitable. Skin wound healing relies on a series of complex physiochemical processes that remain a big challenge for healthcare professionals, particularly when the wounds are colonized by bacteria. Wound dressings play a major role in wound healing as they manage the wounded site, controlling the moisture balance and protecting the wound from repeated trauma, and by preventing possible infections from developing into more serious complications. Recently, bioactive dressings loaded with drugs and/or antimicrobial agents, allowing for a continuous and sustainable release of these molecules at the wounded site, have appeared in the market. Antimicrobial resistance is a growing health care problem, requiring more effective solutions than antibiotics. As such, nano- and microfibrous mats produced via electrospinning technique and loaded with natural-origin antimicrobial agents have attracted a lot of attention. Various polymers have been applied to engineer nanofibrous electrospun dressings. However, the environment impact of the synthesis and processing methods of synthetic polymers is undesirable. Therefore, the application of cellulose-derived materials (highly abundant polymer of natural-origin) becomes crucial as a green alternative to produce electrospun wound dressings with superior wettability, breathability and high capacity to promote cell proliferation, at relatively low costs. In this paper, different biomolecules loaded onto cellulose acetate (CA)-based polymeric nanofibers were investigated, and their antimicrobial properties were highlighted as alternatives to conventional antibiotics.Authors acknowledge the Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Competitive Factors Operational Program (POCI) for funding the projects POCI-01-0145-FEDER-028074 and UID/CTM/00264/2019

    HUWE1 cooperates with RAS activation to control leukemia cell proliferation and human hematopoietic stem cells differentiation fate

    Get PDF
    Acute myeloid leukemia (AML) is a poor prognosis hematopoietic malignance characterized by abnormal proliferation and differentiation of hematopoietic stem cells (HSCs). Although advances in treatment have greatly improved survival rates in young patients, in the elderly population, ~70% of patients present poor prognosis. A pan-cancer analysis on the TCGA cohort showed that AML has the second higher HUWE1 expression in tumor samples among all cancer types. In addition, pathway enrichment analysis pointed to RAS signaling cascade as one of the most important pathways associated to HUWE1 expression in this particular AML cohort. In silico analysis for biological processes enrichment also revealed that HUWE1 expression is correlated with 13 genes involved in myeloid differentiation. Therefore, to understand the role of HUWE1 in human hematopoietic stem and progenitor cells (HSPC) we constitutively expressed KRASG12V oncogene concomitantly to HUWE1 knockdown in stromal co-cultures. The results showed that, in the context of KRASG12V, HUWE1 significantly reduces cell cumulative growth and changes myeloid differentiation profile of HSPCs. Overall, these observations suggest that HUWE1 might contribute to leukemic cell proliferation and impact myeloid differentiation of human HSCs, thus providing new venues for RAS-driven leukemia targeted therapy approach

    Capsule Endoscopy: A Valuable Tool in the Follow-Up of People With Celiac Disease on a Gluten-Free Diet

    Get PDF
    OBJECTIVES: Traditional celiac disease guidelines recommend follow-up endoscopy and duodenal biopsies at 6–12 months after commencing a gluten-free diet (GFD). However, histology may remain abnormal even 1–2 years later. We evaluated the role of capsule endoscopy in patients with celiac disease after treatment with a GFD. METHODS: Twelve adult patients with newly diagnosed celiac disease were prospectively enrolled. All patients had baseline symptom assessment, celiac serology (tissue transglutaminase antibody, tTG), and capsule endoscopy. Twelve months after commencing a GFD, patients underwent repeat symptom assessment, celiac serology, upper gastrointestinal endoscopy, and capsule endoscopy. RESULTS: At baseline, capsule endoscopy detected endoscopic markers of villous atrophy in the duodenum and extending to a variable distance along the small intestine. On the basis of small bowel transit time, the mean±s.e.m. percentage of small intestine with villous atrophy was 18.2±3.7%. After 12 months on a GFD, repeat capsule endoscopy demonstrated mucosal healing from a distal to proximal direction, and the percentage of small intestine with villous atrophy was significantly reduced to 3.4±1.2% (P¼0.0014) and this correlated with improvement in the symptom score (correlation 0.69, P¼0.01). There was a significant improvement in symptom score (5.2±1.0 vs. 1.7±0.4, P¼0.0012) and reduction in immunoglobulin A–tTG levels (81.5±10.6 vs. 17.5±8.2, P¼0.0005). However, 42% of subjects demonstrated persistent villous abnormality as assessed by duodenal histology. CONCLUSIONS: After 12 months on a GFD, patients with celiac disease demonstrate an improvement in symptoms, celiac serology, and the extent of disease as measured by capsule endoscopy. Mucosal healing occurs in a distal to proximal direction. The extent of mucosal healing correlates with improvement in symptoms. Duodenal histology does not reflect the healing that has occurred more distally.Ilmars Lidums, Edward Teo, John Field and Adrian G. Cummin

    Mutations with epigenetic effects in myeloproliferative neoplasms and recent progress in treatment: Proceedings from the 5th International Post-ASH Symposium

    Get PDF
    Immediately following the 2010 annual American Society of Hematology (ASH) meeting, the 5th International Post-ASH Symposium on Chronic Myelogenous Leukemia and BCR-ABL1-Negative Myeloproliferative Neoplasms (MPNs) took place on 7–8 December 2010 in Orlando, Florida, USA. During this meeting, the most recent advances in laboratory research and clinical practice, including those that were presented at the 2010 ASH meeting, were discussed among recognized authorities in the field. The current paper summarizes the proceedings of this meeting in BCR-ABL1-negative MPN. We provide a detailed overview of new mutations with putative epigenetic effects (TET oncogene family member 2 (TET2), additional sex comb-like 1 (ASXL1), isocitrate dehydrogenase (IDH) and enhancer of zeste homolog 2 (EZH2)) and an update on treatment with Janus kinase (JAK) inhibitors, pomalidomide, everolimus, interferon-α, midostaurin and cladribine. In addition, the new ‘Dynamic International Prognostic Scoring System (DIPSS)-plus' prognostic model for primary myelofibrosis (PMF) and the clinical relevance of distinguishing essential thrombocythemia from prefibrotic PMF are discussed

    IDH1 and IDH2 mutation studies in 1473 patients with chronic-, fibrotic- or blast-phase essential thrombocythemia, polycythemia vera or myelofibrosis

    Get PDF
    In a multi-institutional collaborative project, 1473 patients with myeloproliferative neoplasms (MPN) were screened for isocitrate dehydrogenase 1 (IDH1)/IDH2 mutations: 594 essential thrombocythemia (ET), 421 polycythemia vera (PV), 312 primary myelofibrosis (PMF), 95 post-PV/ET MF and 51 blast-phase MPN. A total of 38 IDH mutations (18 IDH1-R132, 19 IDH2-R140 and 1 IDH2-R172) were detected: 5 (0.8%) ET, 8 (1.9%) PV, 13 (4.2%) PMF, 1 (1%) post-PV/ET MF and 11 (21.6%) blast-phase MPN (P<0.01). Mutant IDH was documented in the presence or absence of JAK2, MPL and TET2 mutations, with similar mutational frequencies. However, IDH-mutated patients were more likely to be nullizygous for JAK2 46/1 haplotype, especially in PMF (P=0.04), and less likely to display complex karyotype, in blast-phase disease (P<0.01). In chronic-phase PMF, JAK2 46/1 haplotype nullizygosity (P<0.01; hazard ratio (HR) 2.9, 95% confidence interval (CI) 1.7–5.2), but not IDH mutational status (P=0.55; HR 1.3, 95% CI 0.5–3.4), had an adverse effect on survival. This was confirmed by multivariable analysis. In contrast, in both blast-phase PMF (P=0.04) and blast-phase MPN (P=0.01), the presence of an IDH mutation predicted worse survival. The current study clarifies disease- and stage-specific IDH mutation incidence and prognostic relevance in MPN and provides additional evidence for the biological effect of distinct JAK2 haplotypes

    IDH mutations in primary myelofibrosis predict leukemic transformation and shortened survival: clinical evidence for leukemogenic collaboration with JAK2V617F

    Get PDF
    Isocitrate dehydrogenase (IDH) mutations are frequent in blast-phase myeloproliferative neoplasms and might therefore contribute to leukemic transformation. We examined this possibility in 301 consecutive patients with chronic-phase primary myelofibrosis (PMF). The mutant IDH was detected in 12 patients (4%): 7 IDH2 (5 R140Q, 1 R140W and 1 R172G) and 5 IDH1 (3 R132S and 2 R132C). In all, 6 (50%) of the 12 IDH-mutated patients also expressed JAK2V617F. Overall, 18 (6%) patients displayed only MPL and 164 (54.3%) only JAK2 mutations. Multivariable analysis that accounted for conventional risk factors disclosed inferior overall survival (OS; P=0.03) and leukemia-free survival (LFS; P=0.003) in IDH-mutated patients: OS hazard ratio (HR) was 0.39 (95% confidence interval (95% CI) 0.2–0.75), 0.50 (95% CI 0.27–0.95) and 0.53 (95% CI 0.23–1.2) for patients with no, JAK2 or MPL mutations, respectively. Further analysis disclosed a more pronounced effect for the mutant IDH on OS and LFS in the presence (P=0.0002 and P<0.0001, respectively) as opposed to the absence (P=0.34 and P=0.64) of concomitant JAK2V617F. Analysis of paired samples obtained during chronic- and blast-phase disease revealed the presence of both IDH and JAK2 mutations at both time points. Our observations suggest that IDH mutations in PMF are independent predictors of leukemic transformation and raise the possibility of leukemogenic collaboration with JAK2V617F
    corecore