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1.
Oxid Med Cell Longev ; 2019: 9481390, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827711

RESUMO

Microalgae are generally considered an excellent source of vitamins, minerals, and bioactive molecules that make them suitable to be introduced in cosmetics, pharmaceuticals, and food industries. Aphanizomenon flos-aquae (AFA), an edible microalga, contains numerous biomolecules potentially able to prevent some pathologies including age-related disorders. With the aim to include an AFA extract (Klamin®) as a functional ingredient in baked products, we investigated if its bioactive molecules are destroyed or inactivated after standard cooking temperature. The AFA extract was exposed to heat stress (AFA-HS), and no significant decrease in pigment, polyphenol, and carotenoid content was detected by spectroscopic analysis. Thermal stability of AFA-HS extract was demonstrated by thermogravimetric analysis (TGA), and no change in the morphology of the granules of the powder was noticed by SEM microscopic observation. By Folin-Ciocalteu, ORAC, and ABTS assays, no change in the antioxidant activity and polyphenol contents was found after high-temperature exposition. When added in cell culture, solubilized AFA-HS lost neither its scavenging ability against ROS generation nor its protective role against Abeta, the main peptide involved in Alzheimer's disease. Prebiotic and antioxidant activities of AFA extract that are not lost after thermal stress were verified on E. coli bacteria. Finally, AFA-HS cookies, containing the extract as one of their ingredients, showed increased polyphenols. Here, we evaluate the possibility to use the AFA extract to produce functional food and prevent metabolic and age-related diseases.


Assuntos
Antioxidantes/farmacologia , Aphanizomenon/química , Escherichia coli/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Temperatura Alta , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pão/análise , Culinária , Escherichia coli/efeitos dos fármacos , Farinha/análise , Humanos
2.
J Mater Chem B ; 6(6): 930-939, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32254373

RESUMO

Properly engineered scaffolds combined with functional neurons can be instrumental for the effective repair of the neural tissue. In particular, it is essential to investigate how three-dimensional (3D) systems and topographical features can impact on neuronal activity to obtain engineered functional neural tissues. In this study, polyphenylene sulfone (PPSu) scaffolds constituted by randomly distributed or aligned electrospun nanofibers were fabricated to evaluate the neural activity in 3D culture environments for the first time. The obtained results demonstrated that the nanofibers can successfully support the adhesion and growth of neural stem cells (NSCs) and enhance neuronal differentiation compared to 2D substrates. In addition, NSCs could spread and migrate along the aligned fibers. The percentage of active NSC-derived neurons and the overall network activity in the fibrous substrates were also remarkably enhanced. Finally, the data of neuronal activity showed not only that the neurons cultured on the nanofibers are part of a functional network, but also that their activity increases, and the direction of neural signals can be controlled in the aligned 3D scaffolds.

3.
RSC Adv ; 8(14): 7641-7650, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35539125

RESUMO

Fibrous mats with hydrophobic and oleophilic properties have been fabricated and used as absorbents of oil from stable water in oil emulsions. The mats were prepared by initially mixing two polymers, poly(methyl methacrylate) (PMMA) and polycaprolactone (PCL), in a common solvent. The subsequent electrospinning of the prepared solutions resulted in the production of mechanically stable fiber mats, with enhanced oil absorption capacity and oil absorption selectivity from the emulsions, compared to the pure PMMA or PCL mats. Furthermore, the formed fibrous substrates have been successful in the absorption of oil from different emulsions with a wide range of oil content, from 10 to 80 v%. The performance of the fibrous mats was optimized by the incorporation of hydrophobic silica nanoparticles, reaching oil absorption capacities of 28 g g-1 and negligible water uptake, in the emulsions with 80 v% oil content.

5.
Nanoscale ; 8(45): 19176, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27824205

RESUMO

Correction for 'Ultra-efficient, widely tunable gold nanoparticles-based fiducial markers for X-ray imaging' by Gabriele Maiorano, et al., Nanoscale, 2016, DOI: 10.1039/c6nr07021c.

6.
Nanoscale ; 8(45): 18921-18927, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27812579

RESUMO

We show the development of a new class of highly efficient, biocompatible fiducial markers for X-ray imaging and radiosurgery, based on polymer shells encapsulating engineered gold nanoparticle (AuNP) suspensions. Our smart fabrication strategy enables wide tunability of the fiducial size, shape, and X-ray attenuation performance, up to record values >20 000 Hounsfield units (HU), i.e. comparable to or even higher than bulk gold. We show that the NP fiducials allow for superior imaging both in vitro and in vivo (yet requiring 2 orders of magnitude less material), with strong stability over time and the absence of classical "streak artifacts" of standard bulk fiducials. NP fiducials were probed in vivo, showing exceptional contrast efficiency, even after 2 weeks post-implant in mice.

7.
Biomed Mater ; 11(4): 041001, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27481333

RESUMO

In the biomedical sector the availability of engineered scaffolds and dressings that control and reduce inflammatory states is highly desired, particularly for the management of burn wounds. In this work, we demonstrate for the first time, to the best of our knowledge, that electrospun fibrous dressings of poly(octyl cyanoacrylate) (POCA) combined with polypropylene fumarate (PPF) possess anti-inflammatory activity and promote the fast and effective healing of mild skin burns in an animal model. The fibers produced had an average diameter of (0.8 ± 0.1) µm and they were able to provide a conformal coverage of the injured tissue. The application of the fibrous mats on the burned tissue effectively reduced around 80% of the levels of pro-inflammatory cytokines in the first 48 h in comparison with un-treated animals, and enhanced skin epithelialization. From histological analysis, the skin thickness of the animals treated with POCA : PPF dressings appeared similar to that of one of the naïve animals: (13.7 ± 1.4) µm and (14.3 ± 2.5) µm for naïve and treated animals, respectively. The density of dermal cells was comparable as well: (1100 ± 112) cells mm(-2) and (1358 ± 255) cells mm(-2) for naïve and treated mice, respectively. The results demonstrate the suitability of the electrospun dressings in accelerating and effectively promoting the burn healing process.


Assuntos
Anti-Inflamatórios/farmacologia , Queimaduras/terapia , Modelos Animais de Doenças , Fumaratos/farmacologia , Nanofibras/química , Polipropilenos/farmacologia , Dermatopatias/terapia , Cicatrização/efeitos dos fármacos , Animais , Bandagens , Queimaduras/etiologia , Queimaduras/patologia , Cianoacrilatos/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dermatopatias/etiologia , Dermatopatias/patologia , Raios Ultravioleta/efeitos adversos
8.
J Mater Chem B ; 3(8): 1583-1589, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32262430

RESUMO

Preventing infections is one of the main focuses of wound care. The colonisation of wounds by microorganisms can in fact have negative consequences on the healing process, delaying it. Here, we propose the use of essential oils as natural antimicrobial agents for cellulose-based fibrous dressings. We demonstrate the production of composite electrospun fibres that effectively encapsulate three different types of essential oils (cinnamon, lemongrass and peppermint). The fibrous scaffolds are able to inhibit the growth of Escherichia coli, even when small amounts of essential oils were used. At the same time, they are not cytotoxic, as proved by biocompatibility assays on skin cell models. The created dressings are promising as advanced biomedical devices for topical treatments.

9.
Nanotechnology ; 25(12): 125702, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24572071

RESUMO

Exploiting the intrinsic photosensitivity of TiO2 nanoparticles, we demonstrated how ultraviolet (UV) pulsed laser irradiation of acrylate polymer nanocomposite solutions can separate the initial clusters of these colloidal semiconductor nanorods into clearly distinct units. From the irradiated solutions, optically clear nanocomposite films are obtained which exhibit enhanced optical properties with respect to the nanocomposites obtained without previous UV treatment.

10.
J Nanosci Nanotechnol ; 12(6): 4820-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905535

RESUMO

In this work a new approach is introduced for surface properties control by laser texturing process. By UV laser irradiation, we are able to control the surface wettability of a chitosan polymeric film in which is introduced a chloroauric acid salt by immersion. Specifically the UV irradiation is responsible for the creation of gold nanoparticles at the irradiated surface of the polymeric film. This photolytic process allows us to localize and design accurately surface patterns and moreover to tune metallic particle size in the range of nanoscale. After the characterization of our gold textured surfaces by atomic force and scanning electron microscopies, we demonstrate the link between wettability surface properties and gold nanoparticles size. The experimental results indicate the influence of the laser intensity, the irradiation time and the polymer film thickness (by increasing the gold concentration) on the gold nanoparticle density and size.


Assuntos
Quitosana/química , Quitosana/efeitos da radiação , Cristalização/métodos , Ouro/química , Membranas Artificiais , Nanoestruturas/química , Lasers , Substâncias Macromoleculares/química , Substâncias Macromoleculares/efeitos da radiação , Teste de Materiais , Conformação Molecular/efeitos da radiação , Nanoestruturas/efeitos da radiação , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Polímeros/química , Polímeros/efeitos da radiação , Molhabilidade/efeitos da radiação
11.
J Nanosci Nanotechnol ; 12(6): 4878-82, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905545

RESUMO

In this work we propose the evolution of a new class of optical pressure sensors suitable for robot tactile sensing. The sensors are based on a tapered optical fiber, where optical signals travel embedded into a PDMS-gold nanocomposite material. By applying different pressure forces on the PDMS-based nanocomposite we measure in real time the change of the optical transmitted intensity due to the coupling between the gold nanocomposite material and the tapered fiber region. The intensity reduction of the transmitted light intensity is correlated with the pressure force magnitude.


Assuntos
Dimetilpolisiloxanos/química , Ouro/química , Nanoestruturas/química , Nanotecnologia/instrumentação , Refratometria/instrumentação , Robótica/instrumentação , Transdutores de Pressão , Desenho de Equipamento , Análise de Falha de Equipamento , Nanoestruturas/ultraestrutura , Tato
12.
J R Soc Interface ; 9(76): 3017-26, 2012 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-22696484

RESUMO

We demonstrate high-resolution photocross-linking of biodegradable poly(propylene fumarate) (PPF) and diethyl fumarate (DEF) using UV excimer laser photocuring at 308 nm. The curing depth can be tuned in a micrometre range by adjusting the total energy dose (total fluence). Young's moduli of the scaffolds are found to be a few gigapascal, high enough to support bone formation. The results presented here demonstrate that the proposed technique is an excellent tool for the fabrication of stiff and biocompatible structures on a micrometre scale with defined patterns of high resolution in all three spatial dimensions. Using UV laser photocuring at 308 nm will significantly improve the speed of rapid prototyping of biocompatible and biodegradable polymer scaffolds and enables its production in a few seconds, providing high lateral and horizontal resolution. This short timescale is indeed a tremendous asset that will enable a more efficient translation of technology to clinical applications. Preliminary cell tests proved that PPF : DEF scaffolds produced by excimer laser photocuring are biocompatible and, therefore, are promising candidates to be applied in tissue engineering and regenerative medicine.


Assuntos
Materiais Biocompatíveis/síntese química , Reagentes de Ligações Cruzadas/química , Fumaratos/química , Processos Fotoquímicos , Polipropilenos/química , Fenômenos Biomecânicos , Linhagem Celular Tumoral , Humanos , Lasers , Teste de Materiais , Microscopia Eletrônica de Varredura , Polimerização , Espectrofotometria Ultravioleta
13.
J BUON ; 14(3): 507-10, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19810146

RESUMO

A 26 year-old male was referred to our unit because of a stage III soft tissue sarcoma in the shoulder girdle-axillary area and reduced forearm-distal arm strength. Imaging studies revealed that the tumor encompassed the axillary artery and brachial plexus. We chemoembolized it using vincristine, adriamycin and cyclophosphamide (VAC) plus gel foam and performed limb salvage surgery (LSS) afterwards. The patient received adjuvant chemotherapy (ifosfamide/mesna, adriamycin, and dacarbazine/MAID) and finally radiation therapy (RT; 6500 cGy total dose). Thirty-six months after the operation the patient remains free of disease, without local recurrence and excellent neurological recovery and functional rehabilitation. In stage III soft tissue sarcomas, especially in proximity with major nerve/arterial bundles, a multimodality approach is mandatory; chemoembolization is very effective in shrinking the tumor and defining its margins so as to make feasible a LSS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Embolização Terapêutica , Salvamento de Membro , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Adulto , Antibióticos Antineoplásicos/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Quimioterapia Adjuvante , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Humanos , Masculino , Estadiamento de Neoplasias , Radioterapia Adjuvante , Sarcoma/patologia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Vincristina/uso terapêutico
14.
Nanotechnology ; 20(15): 155302, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19420544

RESUMO

A method of in situ formation of patterns of size controlled CdS nanocrystals in a polymer matrix by pulsed UV irradiation is presented. The films consist of Cd thiolate precursors with different carbon chain lengths embedded in TOPAS polymer matrices. Under UV irradiation the precursors are photolyzed, driving to the formation of CdS nanocrystals in the quantum size regime, with size and concentration defined by the number of incident UV pulses, while the host polymer remains macroscopically/microscopically unaffected. The emission of the formed nanocomposite materials strongly depends on the dimensions of the CdS nanocrystals, thus, their growth at the different phases of the irradiation is monitored using spatially resolved photoluminescence by means of a confocal microscope. X-ray diffraction measurements verified the existence of the CdS nanocrystals, and defined their crystal structure for all the studied cases. The results are reinforced by transmission electron microscopy. It is proved that the selection of the precursor determines the efficiency of the procedure, and the quality of the formed nanocrystals. Moreover it is demonstrated that there is the possibility of laser induced formation of well-defined patterns of CdS nanocrystals, opening up new perspectives in the development of nanodevices.

15.
J Perinatol ; 29(5): 388-90, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19398998

RESUMO

We report a case of ovarian hyperstimulation syndrome associated with fetal trisomy 21. A primigravida presented at 17 1/7 weeks of gestation with abdominal pain because of enlarged ovaries. Multiple fetal abnormalities were seen on pregnancy ultrasound. Fetal trisomy 21 was diagnosed by amniocentesis. The patient's human chorionic gonadotropin level was markedly elevated, as often occurs with fetal trisomy 21, and was likely associated with the ovarian hyperstimulation. Ovarian hyperstimulation syndrome associated with fetal aneuploidy has not been previously described.


Assuntos
Aborto Terapêutico/métodos , Síndrome de Down/complicações , Síndrome de Down/diagnóstico , Síndrome de Hiperestimulação Ovariana/etiologia , Ultrassonografia Pré-Natal , Dor Abdominal/diagnóstico , Dor Abdominal/etiologia , Adulto , Amniocentese/métodos , Feminino , Seguimentos , Humanos , Síndrome de Hiperestimulação Ovariana/diagnóstico por imagem , Paridade , Gravidez , Complicações na Gravidez/diagnóstico por imagem , Segundo Trimestre da Gravidez , Medição de Risco
16.
Langmuir ; 25(11): 6019-23, 2009 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-19391577

RESUMO

In this letter, we report the design and fabrication of different metal patterns for the realization of spatially controlled hydrophobic/hydrophilic regions with micrometer resolution. The fabrication procedure, based on a combination of lithographic techniques and wet-chemistry reactions (namely, spontaneous Galvanic displacement reactions) is reliable, undemanding, and highly versatile, allowing the achievement of precise spatial control along with the use of a wide variety of different materials.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/química , Água/química , Ouro/química , Microquímica , Silício/química , Prata/química , Propriedades de Superfície
17.
J BUON ; 14(1): 57-61, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19373948

RESUMO

PURPOSE: To compare the postoperative outcomes of several techniques of reconstructive surgery for malignant and aggressive benign tumors of the proximal humerus. PATIENTS AND METHODS: Twenty-one shoulder reconstructions following tumor resection were studied. Nine cases with an intracompartmental tumor were treated with endoprosthetic reconstruction. Three cases with the tumor involving the glenoid were treated with a typical Malawer VB shoulder girdle resection. In 5 patients with extracompartmental resections including the rotator cuff or the deltoid muscle a modified Tikhoff-Linberg procedure using polypropylene mesh was performed. In 4 patients with extracompartmental excision the authors proceeded to skeletal reconstruction using a modular endoprosthesis, while soft tissue reconstruction was undertaken using monofilament polypropylene mesh in order to enforce joint stability. RESULTS: All patients achieved stable shoulders. In cases where the technique was modified with mesh the functional outcome was fairly improved and the cosmetic result was excellent. CONCLUSION: For extracompartmental excisions including the deltoid or the rotator cuff the authors recommend a modified Tikhoff-Linberg procedure. Using polypropylene mesh they aim to achieve a static suspension in order to avoid the excessive traction of the neurovascular bundle, which is the most common complication of this procedure. Substitutionally such cases may be treated by reconstruction with a modular endoprosthesis. They recommend stabilization of the prosthesis with the use of mesh implant, avoiding in this way instability.


Assuntos
Artroplastia de Substituição , Neoplasias Ósseas/cirurgia , Úmero/cirurgia , Instabilidade Articular/cirurgia , Procedimentos Ortopédicos , Articulação do Ombro/cirurgia , Adolescente , Adulto , Idoso , Artroplastia de Substituição/instrumentação , Biópsia , Neoplasias Ósseas/patologia , Feminino , Humanos , Úmero/patologia , Prótese Articular , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/instrumentação , Recuperação de Função Fisiológica , Manguito Rotador/cirurgia , Articulação do Ombro/patologia , Articulação do Ombro/fisiopatologia , Telas Cirúrgicas , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
18.
J BUON ; 14(1): 115-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19365880

RESUMO

Bevacizumab, a humanized monoclonal antibody against vascular endothelial factor (VEGF), is approved for the treatment of metastatic colon cancer, but it has also shown efficacy in first line therapy of non-squamous-cell non-smallcell lung cancer, breast cancer and clear-cell renal cancer. Antiangiogenic therapy severe toxic effects such as stroke, myocardial infraction, angina, arterial thromboembolism, pulmonary embolism or haemorrhage, gastrointestinal perforation, heart failure should be taken into account during treatment with bevacizumab. We describe and discuss two cases of cancer patients who developed fatal arterial thromboembolic episodes after administration of bevacizumab. Due to the recent launch of antiangiogenic agents and the limited experience with their use in clinical practice, their adverse effects and pharmacological toxicities, sometimes fatal, are not well-established and a detailed registration of them is needed.


Assuntos
Adenocarcinoma/tratamento farmacológico , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Maxilares/tratamento farmacológico , Sarcoma/tratamento farmacológico , Tromboembolia/induzido quimicamente , Adulto , Anticorpos Monoclonais Humanizados , Anticoagulantes/uso terapêutico , Bevacizumab , Evolução Fatal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tromboembolia/tratamento farmacológico , Tromboembolia/patologia
19.
J BUON ; 13(2): 235-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18555471

RESUMO

PURPOSE: In earlier studies, this laboratory carried out research on the synthesis and anticancer evaluation of hybrid compounds, which combine two molecules in one such as homo-aza-steroidal esters (HASE) of carboxylic derivatives of N, N-bis (2-chloroethyl) aniline. In this combination, steroidal hormones are employed as carriers for transporting the alkylating agents to specific targeted tissues. Aiming to continue our research, we used alkylating agents, as nitrosoureas, instead of nitrogen mustards. In this work the N-[N- (2-chloroethyl)-N-nitroso-carbomoyl]-L-alanine (CNC-ala) has been used and was bound to 7 newly synthesized modified steroidal esters (carrier molecule) of nitrosourea and the hybrid molecules were tested for antitumor activity against PANO2 murine pancreatic adenocarcinoma. MATERIALS AND METHODS: PANO2 adenocarcinoma was used in this study. C57Bl mice were used for chemotherapy evaluation. The activity was assessed from the inhibition of tumor growth and the oncostatic parameter T/C %. RESULTS: The antitumor activity displayed by 7 hybrid steroidal esters of nitrosourea was quite interesting. It was able to discern 4 of 7 compounds that exhibited considerable antitumor activity, increasing the lifespan of the tumor-bearing mice by inhibiting the tumor growth. CONCLUSION: The comparative study of 7 newly synthesized hybrid steroidal esters of nitrosourea shows that the antitumor effects of compound 7, which has an enlarged (7 carbon atoms) A-lactamic ring and nitrosourea esterified at the position 17, which seems to be the most appropriate for the connection of a DNA cross-linking amino acid derivative is superior.


Assuntos
Antineoplásicos/uso terapêutico , Compostos de Nitrosoureia/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Esteroides/farmacologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Alanina/análogos & derivados , Alanina/química , Animais , Carcinoma Ductal Pancreático/secundário , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Compostos de Mostarda Nitrogenada/química , Compostos de Nitrosoureia/síntese química , Neoplasias Pancreáticas/patologia , Esteroides/química , Taxa de Sobrevida , Células Tumorais Cultivadas
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