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1.
Polymers (Basel) ; 16(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38674951

RESUMO

Polymeric materials, renowned for their lightweight attributes and design adaptability, play a pivotal role in augmenting fuel efficiency and cost-effectiveness in railway vehicle development. The tailored formulation of compounds, specifically designed for additive manufacturing, holds significant promise in expanding the use of these materials. This study centers on poly(lactic acid) (PLA), a natural-based biodegradable polymeric material incorporating diverse halogen-free flame retardants (FRs). Our investigation scrutinizes the printability and fire performance of these formulations, aligning with the European railway standard EN 45545-2. The findings underscore that FR in the condensed phase, including ammonium polyphosphate (APP), expandable graphite (EG), and intumescent systems, exhibit superior fire performance. Notably, FR-inducing hydrolytic degradation, such as aluminum hydroxide (ATH) or EG, reduces polymer molecular weight, significantly impacting PLA's mechanical performance. Achieving a delicate balance between fire resistance and mechanical properties, formulations with APP as the flame retardant emerge as optimal. This research contributes to understanding the fire performance and printability of 3D-printed PLA compounds, offering vital insights for the rail industry's adoption of polymeric materials.

2.
Neurooncol Adv ; 2(1): vdaa010, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32642678

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most common malignant primary brain tumor in adults. Circulating biomarkers may assist in the processes of differential diagnosis and response assessment. GBM cells release extracellular vesicles containing a subset of proteins and nucleic acids. We previously demonstrated that exosomes isolated from the serum of GBM patients had an increased expression of RNU6-1 compared to healthy subjects. In this exploratory study, we investigated the role of this small noncoding RNA as a diagnostic biomarker for GBM versus other brain lesions with some potential radiological similarities. METHODS: We analyzed the expression of RNU6-1 in circulating exosomes of GBM patients (n = 18), healthy controls (n = 30), and patients with subacute stroke (n = 30), acute/subacute hemorrhage (n = 30), acute demyelinating lesions (n = 18), brain metastases (n = 21), and primary central nervous system lymphoma (PCNSL; n = 12) using digital droplet PCR. RESULTS: Expression of RNU6-1 was significantly higher in GBM patients than in healthy controls (P = .002). RNU6-1 levels were also significantly higher in exosomes from GBM patients than from patients with non-neoplastic lesions (stroke [P = .05], hemorrhage [P = .01], demyelinating lesions [P = .019]) and PCNSL (P = .004). In contrast, no significant differences were found between patients with GBM and brain metastases (P = .573). Receiver operator characteristic curve analyses supported the role of this biomarker in differentiating GBM from subacute stroke, acute/subacute hemorrhage, acute demyelinating lesions, and PCNSL (P < .05), but again not from brain metastases (P = .575). CONCLUSIONS: Our data suggest that the expression of RNU6-1 in circulating exosomes could be useful for the differentiation of GBM from non-neoplastic brain lesions and PCNSL, but not from brain metastases.

3.
Biomacromolecules ; 21(11): 4522-4531, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32441934

RESUMO

Growing environmental concerns are enforcing sustainable recycling processes for glass substrates, especially bottles, where a fast cleaning and minimization of the use of solvents is desired. In this process, labels and adhesives are mostly removed by the addition of harsh reagents, alkaline solutions, or high temperature, increasing economic costs and harming the environment. Herein, high performance and biobased waterborne pressure-sensitive adhesives with fast removability in water have been developed using small percentages of isosorbide (derived from glucose)-based methacrylate monomers. Formulations containing 2-octyl acrylate and isobornyl methacrylate and small amounts (1 wt %) of these monomers not only yield stronger adhesive fibrils, but also promote a removability in water 6× faster than that of nonisosorbide-based counterparts. This waterborne isosorbide containing PSAs represents an alternative to current PSA formulations toward more sustainable glass recycling and reusing processes.


Assuntos
Adesivos , Isossorbida , Vidro , Metacrilatos , Água
4.
Neuro Oncol ; 16(4): 520-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24435880

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is the most frequent malignant brain tumor in adults, and its prognosis remains dismal despite intensive research and therapeutic advances. Diagnostic biomarkers would be clinically meaningful to allow for early detection of the tumor and for those cases in which surgery is contraindicated or biopsy results are inconclusive. Recent findings show that GBM cells release microvesicles that contain a select subset of cellular proteins and RNA. The aim of this hypothesis-generating study was to assess the diagnostic potential of miRNAs found in microvesicles isolated from the serum of GBM patients. METHODS: To control disease heterogeneity, we used patients with newly diagnosed GBM. In the discovery stage, PCR-based TaqMan Low Density Arrays followed by individual quantitative reverse transcriptase polymerase chain reaction were used to test the differences in the miRNA expression levels of serum microvesicles among 25 GBM patients and healthy controls paired by age and sex. The detected noncoding RNAs were then validated in another 50 GBM patients. RESULTS: We found that the expression levels of 1 small noncoding RNA (RNU6-1) and 2 microRNAs (miR-320 and miR-574-3p) were significantly associated with a GBM diagnosis. In addition, RNU6-1 was consistently an independent predictor of a GBM diagnosis. CONCLUSIONS: Altogether our results uncovered a small noncoding RNA signature in microvesicles isolated from GBM patient serum that could be used as a fast and reliable differential diagnostic biomarker.


Assuntos
Biomarcadores Tumorais/genética , Exossomos/genética , Glioblastoma/diagnóstico , MicroRNAs/genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/sangue , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Glioblastoma/sangue , Glioblastoma/genética , Humanos , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
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