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1.
Sci Rep ; 13(1): 18927, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919374

RESUMO

Phage display is a molecular biology technique that allows the presentation of foreign peptides on the surface of bacteriophages. It is widely utilized for applications such as the discovery of biomarkers, the development of therapeutic antibodies, and the investigation of protein-protein interactions. When employing phages in diagnostic and therapeutic monitoring assays, it is essential to couple them with a detection system capable of revealing and quantifying the interaction between the peptide displayed on the phage capsid and the target of interest. This process is often technically challenging and costly. Here, we generated a fluorescent helper phage vector displaying sfGFP in-frame to the pIII of the capsid proteins. Further, we developed an exchangeable dual-display phage system by combining our newly developed fluorescent helper phage vector with a phagemid vector harboring the engineered pVIII with a peptide-probe. By doing so, the sfGFP and a peptide-probe are displayed on the same phage particle. Notably, our dual-display approach is highly flexible as it allows for easy exchange of the displayed peptide-probe on the pVIII to gain the desired selectivity, while maintaining the sfGFP gene, which allows easy visualization and quantification of the interaction peptide-probe. We anticipate that this system will reduce time and costs compared to the current phage-based detection systems.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Bacteriófagos/metabolismo , Biblioteca de Peptídeos , Peptídeos/química , Proteínas do Capsídeo/genética , Capsídeo/metabolismo
2.
Polymers (Basel) ; 14(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36501713

RESUMO

Adaptive optics (AO) is employed for the continuous measurement and correction of ocular aberrations. Human eye refractive errors (lower-order aberrations such as myopia and astigmatism) are corrected with contact lenses and excimer laser surgery. Under twilight vision conditions, when the pupil of the human eye dilates to 5-7 mm in diameter, higher-order aberrations affect the visual acuity. The combined use of wavefront (WF) technology and AO systems allows the pre-operative evaluation of refractive surgical procedures to compensate for the higher-order optical aberrations of the human eye, guiding the surgeon in choosing the procedure parameters. Here, we report a brief history of AO, starting from the description of the Shack-Hartmann method, which allowed the first in vivo measurement of the eye's wave aberration, the wavefront sensing technologies (WSTs), and their principles. Then, the limitations of the ocular wavefront ascribed to the IOL polymeric materials and design, as well as future perspectives on improving patient vision quality and meeting clinical requests, are described.

3.
Pharmaceutics ; 14(11)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36432694

RESUMO

In this paper, we propose a rational design of a hybrid nanosystem capable of locally delivering a high amount of hydrophobic anticancer drugs (sorafenib or lenvatinib) and heat (hyperthermia) in a remote-controlled manner. We combined in a unique nanosystem the excellent NIR photothermal conversion of gold nanorods (AuNRs) with the ability of a specially designed galactosylated amphiphilic graft copolymer (PHEA-g-BIB-pButMA-g-PEG-GAL) able to recognize hepatic cells overexpressing the asialoglycoprotein receptor (ASGPR) on their membranes, thus giving rise to a smart composite nanosystem for the NIR-triggered chemo-phototherapy of hepatocarcinoma. In order to allow the internalization of AuNRs in the hydrophobic core of polymeric nanoparticles, AuNRs were coated with a thiolated fatty acid (12-mercaptododecanoic acid). The drug-loaded hybrid nanoparticles were prepared by the nanoprecipitation method, obtaining nanoparticles of about 200 nm and drug loadings of 9.0 and 5.4% w/w for sorafenib and lenvatinib, respectively. These multifunctional nanosystems have shown to convert NIR radiation into heat and release charged drugs in a remote-controlled manner. Then, the biocompatibility and synergistic effects of a chemo-phototherapy combination, as well the receptor-mediated internalization, were evaluated by an in vitro test on HepG2, HuH7, and NHDF. The results indicate that the proposed nanoparticles can be considered to be virtuous candidates for an efficient and selective dual-mode therapy of hepatocarcinoma.

4.
Int J Mol Sci ; 23(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35806393

RESUMO

Articular cartilage is characterized by a poor self-healing capacity due to its aneural and avascular nature. Once injured, it undergoes a series of catabolic processes which lead to its progressive degeneration and the onset of a severe chronic disease called osteoarthritis (OA). In OA, important alterations of the morpho-functional organization occur in the cartilage extracellular matrix, involving all the nearby tissues, including the subchondral bone. Osteochondral engineering, based on a perfect combination of cells, biomaterials and biomolecules, is becoming increasingly successful for the regeneration of injured cartilage and underlying subchondral bone tissue. To this end, recently, several peptides have been explored as active molecules and enrichment motifs for the functionalization of biomaterials due to their ability to be easily chemically synthesized, as well as their tunable physico-chemical features, low immunogenicity issues and functional group modeling properties. In addition, they have shown a good aptitude to penetrate into the tissue due to their small size and stability at room temperature. In particular, growth-factor-derived peptides can play multiple functions in bone and cartilage repair, exhibiting chondrogenic/osteogenic differentiation properties. Among the most studied peptides, great attention has been paid to transforming growth factor-ß and bone morphogenetic protein mimetic peptides, cell-penetrating peptides, cell-binding peptides, self-assembling peptides and extracellular matrix-derived peptides. Moreover, recently, phage display technology is emerging as a powerful selection technique for obtaining functional peptides on a large scale and at a low cost. In particular, these peptides have demonstrated advantages such as high biocompatibility; the ability to be immobilized directly on chondro- and osteoinductive nanomaterials; and improving the cell attachment, differentiation, development and regeneration of osteochondral tissue. In this context, the aim of the present review was to go through the recent literature underlining the importance of studying novel functional motifs related to growth factor mimetic peptides that could be a useful tool in osteochondral repair strategies. Moreover, the review summarizes the current knowledge of the use of phage display peptides in osteochondral tissue regeneration.


Assuntos
Cartilagem Articular , Osteoartrite , Materiais Biocompatíveis/química , Cartilagem Articular/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Osteoartrite/terapia , Osteogênese , Peptídeos/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química
5.
Int J Mol Sci ; 22(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34769212

RESUMO

Brain tumors are particularly aggressive and represent a significant cause of morbidity and mortality in adults and children, affecting the global population and being responsible for 2.6% of all cancer deaths (as well as 30% of those in children and 20% in young adults). The blood-brain barrier (BBB) excludes almost 100% of the drugs targeting brain neoplasms, representing one of the most significant challenges to current brain cancer therapy. In the last decades, carbon dots have increasingly played the role of drug delivery systems with theranostic applications against cancer, thanks to their bright photoluminescence, solubility in bodily fluids, chemical stability, and biocompatibility. After a summary outlining brain tumors and the current drug delivery strategies devised in their therapeutic management, this review explores the most recent literature about the advances and open challenges in the employment of carbon dots as both diagnostic and therapeutic agents in the treatment of brain cancers, together with the strategies devised to allow them to cross the BBB effectively.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Carbono/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Animais , Antineoplásicos/farmacocinética , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Humanos
6.
Nanomaterials (Basel) ; 11(10)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34685075

RESUMO

Implantable biomaterials play a key role for the success of orthopedic surgery procedures. However, infections remain one of the most damaging post-operative complications that lead to the implant failure. Recently, several approaches have been proposed to avoid or manage implant-associated infections. Among these, an appropriate surface functionalization to confer intrinsic antibacterial properties preserving the osteo-integration ability represents an appealing strategy for the development of innovative implant materials. Titanium and its alloys are the most used materials for manufacturing of both articular and bone skull prostheses as well as dental implants. However, to date there is still a significant clinical need to improve their bioactivity, osseointegration and antibacterial activity. In this study, titanium biomimetic scaffolds are prepared by nano-functionalization with TiO2 (Ti_TiO2) and γFe2O3 (Ti_γFe2O3). Both cytocompatibility and antibacterial activity have been evaluated. Data show that both nano-functionalized scaffolds exhibit a good antibacterial activity towards Staphylococcus aureus, reducing colony number to 99.4% (Ti_TiO2) and 99.9% (Ti_γFe2O3), respectively. In addition, an increase of both human adipose-derived mesenchymal stem cells (hADSCs) cell proliferation (up to 4.3-fold for Ti_TiO2 and 3.7-fold for Ti_γFe2O3) and differentiation has been observed. These data suggest that these nano-functionalized titanium substrates represent promising prototypes for new antimicrobial and osteoconductive biomaterials to be used in the orthopedic field to reconstruct significant bone defect.

7.
Cancers (Basel) ; 13(9)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919096

RESUMO

Carbon Dots (CDs) are the latest members of carbon-based nanomaterials, which since their discovery have attracted notable attention due to their chemical and mechanical properties, brilliant fluorescence, high photostability, and good biocompatibility. Together with the ease and affordable preparation costs, these intrinsic features make CDs the most promising nanomaterials for multiple applications in the biological field, such as bioimaging, biotherapy, and gene/drug delivery. This review will illustrate the most recent applications of CDs in the biomedical field, focusing on their biocompatibility, fluorescence, low cytotoxicity, cellular uptake, and theranostic properties to highlight above all their usefulness as a promising tool for cancer diagnosis and therapy.

8.
Biomolecules ; 11(3)2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669093

RESUMO

Osteoarthritis (OA) is one of the most common and widespread diseases which is highly disabling for humans. This makes OA a chronic disease for which it is urgent to find new therapeutic strategies. The inflammatory state in OA contributes to its progression through multiple mechanisms involving the recruitment of phagocytes and leukocytes, inflammatory response, and reactive oxygen species (ROS) production. Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl) is classifiable as a piperidine nitroxide, with excellent antioxidant effects, while its anti-inflammatory role is not yet clear. On this basis, we explored its promising biological properties in two in vitro model:, macrophage (J774) and chondrocyte (CC) cell lines. With this aim in mind, we induced inflammation in J774 and CC using lipopolysaccharide (LPS) and Interleukin1ß (IL-1ß), and after 24, 72 and 168 h of tempol treatment analyzed their effects on cytotoxicity and anti-inflammatory activity. Our data suggested that tempol treatment is able to reduce inflammation and nitrite production in LPS-induced J774 as well as reducing the production of proinflammatory mediators including cytokines, enzymes, and metalloproteases (MMPs) in IL-1ß-stimulated CC. Thus, since inflammation and oxidative stress have a crucial role in the pathogenesis and progression of OA, tempol could be considered as a new therapeutic approach for this pathology.


Assuntos
Óxidos N-Cíclicos/uso terapêutico , Inflamação/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Animais , Sobrevivência Celular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Interferon beta/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metaloproteases/metabolismo , Osteoartrite/induzido quimicamente , Osteoartrite/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Marcadores de Spin
9.
Biotechnol Bioeng ; 118(4): 1456-1465, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33289093

RESUMO

The heavy metals pollution represents one of the important issues in the environmental field since it is involved in many pathologies from cancer, neurodegenerative, and metabolic diseases. We propose an innovative portable biosensor for the determination of traces of trivalent arsenic (As(III)) and bivalent mercury (Hg(II)) in water. The system implements a strategy combining two advanced sensing modules consisting in (a) a whole cell based on engineered Escherichia coli as selective sensing element towards the metals and (b) an electrochemical miniaturised silicon device with three microelectrodes and a portable reading system. The sensing mechanism relies on the selective recognition from the bacterium of given metals producing the 4-aminophenol redox active mediator detected through a cyclic voltammetry analysis. The miniaturized biosensor is able to operate a portable, robust, and high-sensitivity detection of As(III) with a sensitivity of 0.122 µA ppb-1 , LoD of 1.5 ppb, and a LoQ of 5 ppb. The LoD value is one order of magnitude below of the value indicated to WHO to be dangerous (10 µg/L). The system was proved to be fully versatile being effective in the detection of Hg(II) as well. A first study on Hg(II) showed sensitivity value of 2.11 µA/ppb a LOD value of 0.1 ppb and LoQ value of 0.34 ppb. Also in this case, the detected LOD was 10 times lower than that indicated by WHO (1 ppb). These results pave the way for advanced sensing strategies suitable for the environmental monitoring and the public safety.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Escherichia coli , Mercúrio/análise , Poluentes Químicos da Água/análise , Água/análise , Cátions Bivalentes/análise , Escherichia coli/genética , Escherichia coli/metabolismo
10.
J Imaging ; 6(12)2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34460530

RESUMO

Immunotherapy is regarded as one of the most significant breakthroughs in cancer treatment. Unfortunately, only a small percentage of patients respond properly to the treatment. Moreover, to date, there are no efficient bio-markers able to early discriminate the patients eligible for this treatment. In order to help overcome these limitations, an innovative non-invasive deep pipeline, integrating Computed Tomography (CT) imaging, is investigated for the prediction of a response to immunotherapy treatment. We report preliminary results collected as part of a case study in which we validated the implemented method on a clinical dataset of patients affected by Metastatic Urothelial Carcinoma. The proposed pipeline aims to discriminate patients with high chances of response from those with disease progression. Specifically, the authors propose ad-hoc 3D Deep Networks integrating Self-Attention mechanisms in order to estimate the immunotherapy treatment response from CT-scan images and such hemato-chemical data of the patients. The performance evaluation (average accuracy close to 92%) confirms the effectiveness of the proposed approach as an immunotherapy treatment response biomarker.

11.
Chemistry ; 23(32): 7672-7676, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28444786

RESUMO

A mesoporous silica material prepared by using folic acid (FA) as a template enables the effective encapsulation of meso-tetrakis(4-carboxyphenyl)porphyrin (TCPP) in its interior. Combination of steady-state and time-resolved absorption and emission spectroscopy demonstrate that FA and TCPP are released from the silica material to the aqueous phase in the form of a non-covalent assembly. This assembly does not form by simple mixing of the two components in the absence of silica, suggesting the key role of the material in the assembling process. The FA/TCPP assembly exhibits dual color fluorescence in the visible region, good photosensitization capability of singlet oxygen, and enhanced photo-induced mortality in KB cancer cells overexpressing folate receptor, if compared with the free components.

12.
Sensors (Basel) ; 17(4)2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28398227

RESUMO

Colorectal cancer (CRC) is an aggressive human malignancy with a complex genomic landscape harboring KRAS mutations. In 40%-60% of patients with CRC, constantly active KRAS proteins affect the prognosis, surgical strategy, and clinical benefit from therapy with anti-epidermal growth factor receptor (EGFR) agents. For this reason, there is a greater demand for minimally-invasive diagnostic devices to characterize the genetic pattern and prevent the acquired mechanism to drug resistance. The rapid developments in cutting-edge diagnostic techniques are expected to play a growing role in medicine and represent an attractive promise to identify potential responders to personalized medicine. Here we propose a new method to simultaneously detect the main KRAS mutations on the portable real-time PCR Q3 platform. This platform is based on hybrid silicon-plastic technology implemented in a miniaturized chip able to achieve a sample-in answer-out rapid analysis, allowing a new approach to genetic counseling and testing.


Assuntos
Reação em Cadeia da Polimerase em Tempo Real , Antineoplásicos , Neoplasias Colorretais , Receptores ErbB , Genótipo , Humanos , Mutação , Proteínas Proto-Oncogênicas p21(ras)
13.
ACS Med Chem Lett ; 8(3): 361-365, 2017 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-28337331

RESUMO

Nitric oxide (NO) release from a suitable NO photodonor (NOP) can be fine-tuned by visible light stimuli at doses that are not toxic to cells but that inhibit several efflux pumps; these are mainly responsible for the multidrug resistance of the anticancer agent doxorubicin (DOX). The strategy may thus increase DOX toxicity against resistant cancer cells. Moreover, a novel molecular hybrid covalently joining DOX and NOP showed similar increased toxicity toward resistant cancer cells and, in addition, lower cardiotoxicity than DOX. This opens new and underexplored approaches to overcoming the main therapeutic drawbacks of this chemotherapeutic based on light-controlled release of NO.

14.
J Phys Chem B ; 112(37): 11517-28, 2008 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-18717554

RESUMO

Thin films of a newly synthesized iron(III) porphyrazine, LFeOESPz ( L = ClEtO, OESPz = ethylsulfanylporphyrazine), have been deposited by the Langmuir-Schafer (LS) technique (horizontal lifting) on ITO or gold substrates. Before deposition, the floating films have been investigated at the air-water interface by pressure/area per molecule (pi/ A) experiments, Brewster angle microscopy (BAM) and UV-vis reflection spectroscopy (RefSpec). The complex reacts with water subphase (pH 6.2) forming the mu-oxo dimer, which becomes the predominant component of the LS films ( LS-Fe) as indicated by optical, IR, XPS, and electrochemical data. LS-Fe multilayers exhibit, between open circuit potential (OCP) and +0.90 V (vs SCE), two independent peak pairs with formal potentials, E surf (I) and E surf(II) of +0.56 V and +0.78 V, respectively. According to dynamic voltammetric and coulometric experiments the peak pair at +0.56 V is attributed to one-electron process at the iron(III) centers on the monomer, while the peak pair at +0.78 V is associated to a four-electron process involving mu-oxo-dimer oligomers. LS-Fe films prove to be quite stable electrochemically between OCP and +0.90 V. The electrochemical stability decreases, however, when the potential range is extended both anodically and cathodically outside these limits, due to formation of new species. Upon incubation with TCA solutions, LS-Fe films show remarkable changes in the UV-vis spectra, which are consistent with a significant mu-oxo dimer --> monomer conversion. Addition of TCA to the electrochemical cell using a LS-Fe film as working electrode, results in a linear increase of a cathodic current peak near -0.40 V as the TCA concentration varies in the 0.1-2.0 mM range. This behavior is interpreted in terms of TCA inducing a progressive change in the composition of the LS-Fe films in favor of the monomeric iron(III) porphyrazine, which is responsible for the observed increase in the cathodic current near -0.40 V.


Assuntos
Ferro/química , Compostos Organometálicos/síntese química , Porfirinas/química , Cátions , Dimerização , Eletroquímica , Análise Espectral
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