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1.
J Med Life ; 16(8): 1201-1210, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38024830

RESUMO

Hodgkin lymphoma (HL) has become one of the most curable hematological neoplasia. Clinical and biological factors remain the main pillars guiding therapeutic strategies in HL. Recent studies have improved our understanding of the phenotype, the characteristics of histogenesis, and other possible mechanisms of lymphomagenesis, including the role of Epstein-Barr virus (EBV) infection. Tumor cells manipulate the microenvironment, allowing them to develop their malignant phenotype and evade the attack of the host's immune response so that the interaction between tumor cells and the reactive microenvironment determines not only the histological features but also the clinical-pathological characteristics and prognosis of these patients - essential for the development of future therapies targeting various other cellular components of the tumor microenvironment. This article aimed to evaluate the characteristics of the tumor microenvironment and malignant cells using histopathology and immunohistochemistry (IHC) techniques to highlight the association of EBV and to study the expression of characteristic antigens in malignant and non-malignant cells within the tumor mass (overexpression of BCL2 (B-cell lymphoma 2) in malignant cells, presence of PD1 (Programmed cell death Protein 1) on T lymphocytes, CD68+ macrophages in the tumor microenvironment, and presence of EGFR (epidermal growth factor receptor). The analysis of the data collected in this paper highlights several key parameters with prognostic value and statistical significance: the EBV infection at diagnosis, its association with low-intensity BCL2(+), the presence of CD68 with rosette formation, and the identification of specific vascularization patterns. The development of prognostic systems that take into account the integration of biological prognostic markers seems essential for a better risk stratification.


Assuntos
Infecções por Vírus Epstein-Barr , Doença de Hodgkin , Humanos , Doença de Hodgkin/metabolismo , Doença de Hodgkin/patologia , Infecções por Vírus Epstein-Barr/complicações , Prognóstico , Herpesvirus Humano 4/genética , Microambiente Tumoral , Proteínas Proto-Oncogênicas c-bcl-2
2.
Int J Biol Macromol ; 230: 123162, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623620

RESUMO

Due to its inherent properties and wide availability, cellulose acetate is an extremely competitive candidate for the production of polymeric membranes. However, for best results in particular applications, membrane modification is required in order to minimize unwanted interactions and introduce novel characteristics to the pristine polymer. In this study, the surface of commercial cellulose acetate membranes was functionalized with 4'-aminobenzo-15-crown-5 ether, using a covalent bonding approach. The main goal was the improvement of the membranes biomineralization ability, thus making them prospective materials for bone regeneration applications. The proposed reaction mechanism was confirmed by XPS and NMR analysis while the presence of the functionalization agents in the membranes structure was showed by ATR FT-IR and Raman spectra. The effects of the functionalization process on the morphology, thermal and mechanical properties of the membranes were studied by SEM, TGA and tensile tests. The obtained results revealed that the cellulose acetate membranes were successfully functionalized with crown ether and provided a good understanding of the interactions that took place between the polymer and the functionalization agents. Moreover, promising results were obtained during the Taguchi biomineralization studies. SEM images, EDX mapping and XRD spectra indicating that the CA-AB15C5 membranes have a superior Ca2+ ions retention ability, this causing an accentuated calcium phosphate deposition on the modified polymeric fibers, compared to the neat CA membrane.


Assuntos
Éteres de Coroa , Osseointegração , Espectroscopia de Infravermelho com Transformada de Fourier , Polímeros/química , Membranas Artificiais
3.
Polymers (Basel) ; 13(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34833276

RESUMO

This study presents a new, revolutionary, and easy method of separating Gd (III). For this purpose, a cellulose acetate membrane surface was modified in three steps, as follows: firstly, with aminopropyl triethoxysylene; then with glutaraldehyde; and at the end, by immobilization of crown ethers. The obtained membranes were characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), through which the synthesis of membranes with Gd (III) separation properties is demonstrated. In addition, for the Gd (III) separating process, a gadolinium nitrate solution, with applications of moderator poison in nuclear reactors, was used. The membranes retention performance has been demonstrated by inductively coupled plasma mass spectrometry (ICP-MS), showing a separation efficiency of up to 91%, compared with the initial feed solution.

4.
Polymers (Basel) ; 14(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35012170

RESUMO

Heavy metal poisoning is a rare health condition caused by the accumulation of toxic metal ions in the soft tissues of the human body that can be life threatening if left untreated. In the case of severe intoxications, hemodialysis is the most effective method for a rapid clearance of the metal ions from the bloodstream, therefore, the development of hemodialysis membranes with superior metal ions retention ability is of great research interest. In the present study, synthetic polysulfone membranes were modified with reduced graphene oxide functionalized with crown ether, an organic compound with high metal ions complexation capacity. The physico-chemical characteristics of the composite membranes were determined by FT-IR, Raman, XPS and SEM analysis while their efficiency in retaining metal ions was evaluated via ICP-MS analysis. The obtained results showed that the thermal stability of reduced graphene oxide was improved after functionalization with crown ether and that the presence of the carbonaceous filler influenced the membranes morphology in terms of pore dimensions and membrane thickness. Moreover, the ability of Cu2+ ions retention from synthetic feed solution was up to three times higher in the case of the composite membranes compared to the neat ones.

5.
Materials (Basel) ; 13(23)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255827

RESUMO

Tissue engineering is an interdisciplinary field that combines principles of engineering and life sciences to obtain biomaterials capable of maintaining, improving, or substituting the function of various tissues or even an entire organ. In virtue of its high availability, biocompatibility and versatility, cellulose was considered a promising platform for such applications. The combination of cellulose with graphene or graphene derivatives leads to the obtainment of superior composites in terms of cellular attachment, growth and proliferation, integration into host tissue, and stem cell differentiation toward specific lineages. The current review provides an up-to-date summary of the status of the field of cellulose composites with graphene for tissue engineering applications. The preparation methods and the biological performance of cellulose paper, bacterial cellulose, and cellulose derivatives-based composites with graphene, graphene oxide and reduced graphene oxide were mainly discussed. The importance of the cellulose-based matrix and the contribution of graphene and graphene derivatives fillers as well as several key applications of these hybrid materials, particularly for the development of multifunctional scaffolds for cell culture, bone and neural tissue regeneration were also highlighted.

6.
Molecules ; 25(18)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899710

RESUMO

Cellulose is one of the most affordable, sustainable and renewable resources, and has attracted much attention especially in the form of nanocellulose. Bacterial cellulose, cellulose nanocrystals or nanofibers may serve as a polymer support to enhance the effectiveness of metal nanoparticles. The resultant hybrids are valuable materials for biomedical applications due to the novel optical, electronic, magnetic and antibacterial properties. In the present review, the preparation methods, properties and application of nanocellulose hybrids with different metal oxides nanoparticles such as zinc oxide, titanium dioxide, copper oxide, magnesium oxide or magnetite are thoroughly discussed. Nanocellulose-metal oxides antibacterial formulations are preferred to antibiotics due to the lack of microbial resistance, which is the main cause for the antibiotics failure to cure infections. Metal oxide nanoparticles may be separately synthesized and added to nanocellulose (ex situ processes) or they can be synthesized using nanocellulose as a template (in situ processes). In the latter case, the precursor is trapped inside the nanocellulose network and then reduced to the metal oxide. The influence of the synthesis methods and conditions on the thermal and mechanical properties, along with the bactericidal and cytotoxicity responses of nanocellulose-metal oxides hybrids were mainly analyzed in this review. The current status of research in the field and future perspectives were also signaled.


Assuntos
Tecnologia Biomédica , Celulose/química , Metais/química , Nanopartículas/química , Óxidos/química , Antibacterianos/farmacologia , Celulose/ultraestrutura
7.
Carbohydr Polym ; 247: 116683, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32829811

RESUMO

Cellulose derivatives represent a viable alternative to pure cellulose due to their solubility in water and common organic solvents. This, coupled with their low cost, biocompatibility, and biodegradability, makes them an attractive choice for applications related to the biomedicine and bioanalysis area. Cellulose derivatives-based composites with improved properties were researched as films and membranes for osseointegration, hemodialysis and biosensors, smart textile fibers, tissue engineering scaffolds, hydrogels and nanoparticles for drug delivery. The different preparation strategies of these polymeric composites as well as the most recent available experimental results were described in this review. General aspects such as structure and properties of cellulose extracted from plants or bacterial sources, types of cellulose derivatives and their synthesis methods were also discussed. Finally, the future perspectives related to composites based on cellulose derivatives were highlighted and some conclusions regarding the reviewed applications were drawn.


Assuntos
Celulose/análogos & derivados , Celulose/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Técnicas Biossensoriais/métodos , Celulose/isolamento & purificação , Celulose/uso terapêutico , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/uso terapêutico , Nanopartículas/química , Nanopartículas/uso terapêutico , Polímeros/síntese química , Polímeros/química , Polímeros/uso terapêutico , Alicerces Teciduais/química
8.
Materials (Basel) ; 13(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32486050

RESUMO

The development of novel polymeric composites based on cellulose derivatives and hydroxyapatite represents a fascinating and challenging research topic in membranes science and technology. Cellulose-based materials are a viable alternative to synthetic polymers due to their favorable physico-chemical and biological characteristics. They are also an appropriate organic matrix for the incorporation of hydroxyapatite particles, inter and intramolecular hydrogen bonds, as well as electrostatic interactions being formed between the functional groups on the polymeric chains surface and the inorganic filler. The current review presents an overview on the main application fields of cellulose derivatives/hydroxyapatite composite membranes. Considering the versatility of hydroxyapatite particles, the hybrid materials offer favorable prospects for applications in water purification, tissue engineering, drug delivery, and hemodialysis. The preparation technique and the chemical composition have a big influence on the final membrane properties. The well-established membrane fabrication methods such as phase inversion, electrospinning, or gradual electrostatic assembly are discussed, together with the various strategies employed to obtain a homogenous dispersion of the inorganic particles in the polymeric matrix. Finally, the main conclusions and the future directions regarding the preparation and applications of cellulose derivatives/hydroxyapatite composite membranes are presented.

9.
Nanomaterials (Basel) ; 10(1)2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31878292

RESUMO

Biodegradable blends and nanocomposites were produced from polylactic acid (PLA), poly(3-hydroxybutyrate) (PHB) and cellulose nanocrystals (NC) by a single step reactive blending process using dicumyl peroxide (DCP) as a cross-linking agent. With the aim of gaining more insight into the impact of processing methods upon the morphological, thermal and mechanical properties of these nanocomposites, three different processing techniques were employed: compression molding, extrusion, and 3D printing. The addition of DCP improved interfacial adhesion and the dispersion of NC in nanocomposites as observed by scanning electron microscopy and atomic force microscopy. The carbonyl index calculated from Fourier transform infrared spectroscopy showed increased crystallinity after DCP addition in PLA/PHB and PLA/PHB/NC, also confirmed by differential scanning calorimetry analyses. NC and DCP showed nucleating activity and favored the crystallization of PLA, increasing its crystallinity from 16% in PLA/PHB to 38% in DCP crosslinked blend and to 43% in crosslinked PLA/PHB/NC nanocomposite. The addition of DCP also influenced the melting-recrystallization processes due to the generation of lower molecular weight products with increased mobility. The thermo-mechanical characterization of uncross-linked and cross-linked PLA/PHB blends and nanocomposites showed the influence of the processing technique. Higher storage modulus values were obtained for filaments obtained by extrusion and 3D printed meshes compared to compression molded films. Similarly, the thermogravimetric analysis showed an increase of the onset degradation temperature, even with more than 10 °C for PLA/PHB blends and nanocomposites after extrusion and 3D-printing, compared with compression molding. This study shows that PLA/PHB products with enhanced interfacial adhesion, improved thermal stability, and mechanical properties can be obtained by the right choice of the processing method and conditions using NC and DCP for balancing the properties.

10.
Maedica (Bucur) ; 14(2): 144-147, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31523296

RESUMO

Hodgkin lymphoma is a highly curable malignant hemopathy, using chemotherapy, radiotherapy, target therapies and hematopoietic stem cell transplantation. Current research in this field focuses on identifying prognostic factors associated with the pathogenic characteristics of the tumoral process, enabling the therapy to be adjusted to each patient's degree of risk. The identification of biomarkers associated with the tumoral process is extremely important because these molecules can be targets for new biological therapies.

11.
Maedica (Bucur) ; 9(2): 204-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25705280

RESUMO

Composite lymphoma refers to the co-occurrence of two or more morphologically and immunophenotypically separate lymphomas in the same topographic site at the time of clinical presentation. It is an infrequent type of lymphoid neoplasm, present in lymphoid tissue and may be due to the existence of two genetically related neoplasms such as transformation of a single lymphoma into another more aggressive lymphoma or be due to the presence of two clonally unrelated lymphomas. This paper is presenting a case of diffuse non-Hodgkin large B-cell lymphoma with areas of low grade and high grade follicular non-Hodgkin B-cell lymphoma in a retroperitoneal lymph node and spleen of an 62 year old woman. Histopathological examination and immunohistochemistry features proved the diagnosis of composite lymphoma.

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