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1.
Molecules ; 21(8)2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27517898

RESUMO

Palladium nanoparticles, simply and briefly generated in commercial and cheap onium salts using supercritical carbon dioxide, have been found to be an effective catalytic system for additive free N-alkylation reaction using alcohols via cascade oxidation/condensation/reduction steps.


Assuntos
Álcoois/química , Oniocompostos/química , Paládio/química , Alquilação , Aminas/química , Dióxido de Carbono/química , Catálise , Nanopartículas/química , Nanopartículas/ultraestrutura , Oxirredução
2.
Artigo em Inglês | MEDLINE | ID: mdl-35409996

RESUMO

Background: About 10,000 women are diagnosed with breast cancer and about 2000 women are diagnosed with ovarian cancer each year in Romania. There is an insufficient number of genetic studies in the Romanian population to identify patients at high risk of inherited breast and ovarian cancer. Methods: We evaluated 250 women of Romanian ethnicity with BC and 240 women of Romanian ethnicity with ovarian cancer for the presence of damaging germline mutations in breast cancer genes 1 and 2 (BRCA1 and BRCA2, respectively) using Next-Generation Sequencing (NGS) technology. Results: Of the 250 breast cancer patients, 47 carried a disease-predisposing BRCA mutation (30 patients (63.83%) with a BRCA1 mutation and 17 patients (36.17%) with a BRCA2 mutation). Of the 240 ovarian cancer patients, 60 carried a BRCA mutation (43 patients (72%) with a BRCA1 mutation and 17 patients (28%) with a BRCA2 mutation). In the BRCA1 gene, we identified 18 variants (4 in both patient groups (ovarian and breast cancer patients), 1 mutation variant in the BC patient group, and 13 mutation variants in the ovarian cancer patient group). In the BRCA2 gene, we identified 17 variants (1 variant in both ovarian and breast cancer patients, 6 distinct variants in BC patients, and 10 distinct variants in ovarian cancer patients). The prevailing mutation variants identified were c.3607C>T (BRCA1) (18 cases) followed by c.5266dupC (BRCA1) (17 cases) and c.9371A>T (BRCA2) (12 cases). The most prevalent mutation, BRCA1 c.3607C>T, which is less common in the Romanian population, was mainly associated with triple-negative BC and ovarian serous adenocarcinoma. Conclusion: The results of our analysis may help to establish specific variants of BRCA mutations in the Romanian population and identify individuals at high risk of hereditary breast and ovarian cancer syndrome by genetic testing.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Proteína BRCA1/genética , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Carcinoma Epitelial do Ovário , Etnicidade , Feminino , Predisposição Genética para Doença , Humanos , Mutação , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Romênia
3.
Langmuir ; 26(15): 12548-52, 2010 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-20593788

RESUMO

We report here on a fast magneto-optical characterization method for colloidal liquid dispersions of magnetic nanoparticles. We have applied our methodology to Ni nanoparticles with size equal or below 15 nm synthesized by a ligand stabilized solution-phase synthesis. We have measured the magnetic circular dichroism (MCD) of colloidal dispersions and found that we can probe the intrinsic magnetic properties within a wide concentration range, from 10(-5) up to 10(-2) M, with sensitivity to concentrations below 1 microg/mL of magnetic Ni particles. We found that the measured MCD signal scales up with the concentration thus providing a means of determining the concentration values of highly diluted dispersions. The methodology presented here exhibits large flexibility and versatility and might be suitable to study either fundamental problems related to properties of nanosize particles including surface related effects which are highly relevant for magnetic colloids in biomedical applications or to be applied to in situ testing and integration in production lines.


Assuntos
Coloides/química , Nanopartículas Metálicas/química , Níquel/química , Dicroísmo Circular , Magnetismo , Nanotecnologia
4.
Nanoscale ; 5(5): 2126-32, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23386040

RESUMO

Magnetic nanoparticles (NPs) are of increasing interest in various industrially relevant products. For these, the development of greener and faster approaches facilitating scaling-up production is of paramount importance. Here, we report a novel, green and potentially scalable approach for the continuous and ultrafast (90 s) synthesis of superparamagnetic ferrite NPs (MnFe(2)O(4), Fe(3)O(4)) in supercritical ethanol (scEtOH) at a fairly moderate temperature (260 °C). ScEtOH exhibits numerous advantages such as its production from bio-resources, its lack of toxicity and its relatively low supercritical coordinates (p(c) = 6.39 MPa and T(c) = 243 °C), being therefore appropriate for the development of sustainable technologies. The present study is completed by the investigation of both in situ and ex situ NP surface functionalization. The as-obtained nanoparticles present good crystallinity, sizes below 8 nm, superparamagnetic behavior at room temperature and high saturation magnetization. Moreover, depending on the capping strategy, the ferrite NPs present extended (for in situ coated NPs) or short-term (for ex situ coated NPs) colloidal stability.


Assuntos
Etanol/química , Compostos Férricos/química , Nanopartículas de Magnetita/química , Cristalização , Tamanho da Partícula , Tensoativos/química , Temperatura
5.
Nanoscale ; 5(24): 12425-31, 2013 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-24165810

RESUMO

The combination of highly active Pd nanocrystal (NC) types with tailored surface properties (various ligands) - e.g. organic-inorganic hybrid NCs - as catalysts opens avenues towards new synthetic pathways, implying a faster practical alternative for adjusting and screening the reaction conditions. Pd@dppf and Pd@PCy3 NCs have been successfully prepared via a continuous supercritical fluid assisted coflow route with promising results as catalysts in borylation reaction. It has been found that the ligands not only influence the catalytic properties of the systems, but also contribute to Pd metal core characteristics (size, shape and time stability).

6.
ACS Nano ; 5(4): 2957-63, 2011 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-21401054

RESUMO

Three-dimensional magnetophotonic crystals (3D-MPCs) are being postulated as appropriate platforms to tailor the magneto-optical spectral response of magnetic materials and to incorporate this functionality in a new generation of optical devices. By infiltrating self-assembled inverse opal structures with monodisperse nickel nanoparticles we have fabricated 3D-MPCs that show a sizable enhancement of the magneto-optical signal at frequencies around the stop-band edges of the photonic crystals. We have established a proper methodology to disentangle the intrinsic magneto-optical spectra from the nonmagnetic optical activity of the 3D-MPCs. The results of the optical and magneto-optical characterization are consistent with a homogeneous magnetic infiltration of the opal structure that gives rise to both a red-shift of the optical bandgap and a modification of the magneto-optical spectral response due to photonic bandgap effects. The results of our investigation demonstrate the potential of 3D-MPCs fabricated following the approach outlined here and offer opportunities to adapt the magneto-optical spectral response at optical frequencies by appropriate design of the opal structure or magnetic field strength.

7.
Nanoscale ; 3(11): 4811-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21987109

RESUMO

We report on an extremely fast and versatile synthetic approach, based on microwave assisted sol-gel chemistry, that allows a conformal nanometric coating of intricate three-dimensional structures. Using this methodology, we have achieved a conformal coverage of large areas of three-dimensional opals with a superparamagnetic manganese ferrite layer, yielding magneto-photonic crystals with excellent quality. The use of a ternary oxide for the ultrathin coating demonstrates the potential of this methodology to realize three-dimensional structures with complex materials that may find applications beyond photonics, such as energy, sensing or catalysis.


Assuntos
Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Luz , Substâncias Macromoleculares/química , Magnetismo , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
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