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1.
Artigo em Inglês | MEDLINE | ID: mdl-37863392

RESUMO

AIM: To determine the usefulness of neutrophil/lymphocyte (N/L) and platelet/lymphocyte (P/L) ratios as well as quantitative [18F]FDG PET/CT parameters as prognostic factors for overall survival (OS), cancer-specific survival (CSS) and progression-free survival (PFS) in patients with head and neck squamous cell carcinoma (HyN). MATERIAL AND METHODS: Sixty-six patients (56 men) diagnosed with HyN carcinoma were retrospectively assessed over an 8-year interval. Maximum SUV (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) parameters were determined from the PET/CT study at diagnosis. After treatment with chemoradiotherapy, patient survival was assessed. The Cox regression model and the Kaplan-Meier method were used to analyse prognostic factors and survival curves. RESULTS: Median follow-up was 50.4 months, with 39 recurrences-progressions and 39 deaths. In the univariate analysis, metabolic parameters, except SUVmax, were predictive factors for all three survivals and the two blood parameters were predictive for OS and EFS. TLG was the only predictive factor in the multivariate analysis. The three survival curves were significantly different for the metabolic parameters and the OS curve for the N/L ratio. Correlations were seen between N/L ratio, MTV and TLG. No correlations were demonstrated between P/L ratio and metabolic parameters. CONCLUSION: The use of haematological and metabolic markers would allow to identify patients with a high risk of recurrences and por survival and to individualise treatment by applying more aggressive therapies.


Assuntos
Neoplasias de Cabeça e Pescoço , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Masculino , Humanos , Prognóstico , Fluordesoxiglucose F18/metabolismo , Estudos Retrospectivos , Compostos Radiofarmacêuticos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/terapia
2.
ACS Omega ; 8(1): 819-828, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643454

RESUMO

A new selective fluorogenic chemosensor for Hg2+, which combines a calixarene derivative with a BODIPY core as a fluorescent reporter, is described. The remarkable change in its fluorogenic properties in DMSO and CHCl3 has been analyzed. A study of its spectral properties on dilution, along with molecular modeling studies, allowed us to explain that this behavior involves the formation of a J-dimer, as well as how the sensing mechanism of Hg2+ proceeds.

3.
RSC Adv ; 12(44): 28580-28585, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36330338

RESUMO

Synthetic cathinones are a class of new psychoactive substances whose consumption has increased a lot and is widespread throughout the world. Thus, there is currently a need for rapid and simple detection of these drugs. In particular, detection of synthetic cathinones in oral fluid in drivers can be of great importance in preventing traffic accidents. Herein, we report two probes, based on BODIPY derivatives combined with Cu(ii), which are able to detect these drugs both in water and in oral fluid, by changes in color and fluorescence. The determined limits of detection for ephedrone (as a model drug) are lower than the usual concentrations in saliva after intake of this type of drug. The sensing mechanism seems to be related to the cathinone induced reduction of Cu(ii) to Cu(i) with concomitants changes in the BODIPY structure.

4.
Chem Commun (Camb) ; 58(87): 12248, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36268824

RESUMO

Correction for 'Protection against chemical submission: naked-eye detection of γ-hydroxybutyric acid (GHB) in soft drinks and alcoholic beverages' by Silvia Rodríguez-Nuévalos et al., Chem. Commun., 2020, 56, 12600-12603, https://doi.org/10.1039/D0CC05387B.

6.
Analyst ; 146(18): 5601-5609, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34378566

RESUMO

Drug-Facilitated Sexual Assault (DFSA) is a problem of considerable dimensions on a global scale. Among the different compounds used in DFSA assaults, 4-hydroxybutyric acid (GHB) is one of the most elusive due to its physical and biological characteristics. Therefore, the development of real-time detection methods to detect GHB not only in drinks but also in urine is very important for personal and social security. Here, we report two new heteroditopic chemosensors capable of recognizing and detecting GHB in soft drinks, alcoholic beverages and synthetic urine. The compounds have two moieties: a trifluoroacetyl group and a thiourea, which are able to interact respectively with the hydroxyl and the carboxylic groups present in the GHB structure. In addition, the distance between these two groups has been optimized to allow a double interaction which guarantees the recognition even in very competitive media such as beverages or urine samples.


Assuntos
Oxibato de Sódio , Bebidas Alcoólicas/análise , Bebidas/análise , Bebidas Gaseificadas , Hidroxibutiratos/análise
7.
Clin Nucl Med ; 46(12): e603-e604, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34172603

RESUMO

ABSTRACT: We report a 64-year-old woman whose history started with urinary incontinence and neurological symptoms (cognitive impairment, dysarthria, and gait difficulties). The 18F-FDG PET/CT showed hypometabolism of the whole cerebellum. Then 6 months later, she developed tremor, postural instability, and ataxia, so she was hospitalized to complete study. Blood tests (antibodies, vitamin B12, copper, genetic test of spinocerebellar ataxia) did not have alterations, but imaging studies, along with clinical symptoms, provide the diagnosis of possible multiple system atrophy.


Assuntos
Ataxia Cerebelar , Atrofia de Múltiplos Sistemas , Atrofia/patologia , Ataxia Cerebelar/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons
8.
Nanomaterials (Basel) ; 11(3)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806899

RESUMO

A new hybrid organic-inorganic material for sensing spermine (Spm) and spermidine (Spd) has been prepared and characterized. The material is based on MCM-41 particles functionalized with an N-hydroxysuccinimide derivative and loaded with Rhodamine 6G. The cargo is kept inside the porous material due to the formation of a double layer of organic matter. The inner layer is covalently bound to the silica particles, while the external layer is formed through hydrogen and hydrophobic interactions. The limits of detection determined by fluorimetric titration are 27 µM and 45 µM for Spm and Spd, respectively. The sensor remains silent in the presence of other biologically important amines and is able to detect Spm and Spd in both aqueous solution and cells.

9.
ChemSusChem ; 14(1): 208-233, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32871058

RESUMO

Covalent organic frameworks (COFs) are relatively recent materials. They have received great attention due to their interesting properties. However, the application of microwaves in their synthesis, despite its advantages such as faster and more reproducible processes, is a minority. Herein, a comprehensive compilation of the research results published in the microwave-assisted synthesis (MAS) of COFs is presented. This review includes articles of 2D and 3D COFs prepared using microwaves as source of energy. The articles have been classified depending on the functional groups including boronate ester, imines, enamines, azines, and triazines, among others. It compiles the main parameters of synthesis and characteristics of the materials together with some general issues related with COFs and microwaves. Additionally, current and future perspectives of the topic have been discussed.

10.
Sensors (Basel) ; 22(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35009801

RESUMO

A recompilation of applications of mesoporous silica nanoparticles in sensing from the last five years is presented. Its high potential, especially as hybrid materials combined with organic or bio-molecules, is shown. Adding to the multiplying effect of loading high amounts of the transducer into the pores, the selectivity attained by the interaction of the analyte with the layer decorating the material is described. Examples of the different methodologies are presented.


Assuntos
Nanopartículas , Dióxido de Silício , Porosidade
11.
Chem Commun (Camb) ; 56(83): 12600-12603, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32945322

RESUMO

Two new oxazole derivatives, able to detect γ-hydroxybutyric acid (GHB) in soft drinks and alcoholic beverages, by color and fluorescence changes, are reported.

12.
ACS Sens ; 5(9): 2966-2972, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32844649

RESUMO

A bio-inspired nanodevice for the selective and sensitive fluorogenic detection of 3,4-methylenedioxypyrovalerone (MDPV), usually known as Cannibal drug, is reported. The sensing nanodevice is based on mesoporous silica nanoparticles (MSNs), loaded with a fluorescent reporter (rhodamine B), and functionalized on their external surface with a dopamine derivative (3), which specifically interacts with the recombinant human dopamine transporter (DAT), capping the pores. In the presence of MDPV, DAT detaches from the MSNs consequently, causing rhodamine B release and allowing drug detection. The nanosensor shows a detection limit of 5.2 µM, and it is able to detect the MDPV drug both in saliva and blood plasma samples.


Assuntos
Nanopartículas , Preparações Farmacêuticas , Dopamina , Humanos , Dióxido de Silício
13.
Nanomaterials (Basel) ; 10(6)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492889

RESUMO

Microwaves are a source of energy of great interest for chemical synthesis. Among nanomaterials, few are as versatile as silica-it forms mesoporous materials and nanoparticles, it can be incorporated as shells or loaded in composites, it can also be functionalized. Despite the relevant properties of silica, and the advantages of the use of microwave as energy source, its use in silica-based materials is not frequent. We report herein a compilation of the research results published in the last 10 years of microwave assisted synthesis of silica based materials. This review includes examples of mesoporous materials for waste removal, catalysis, drug release, and gas adsorption applications, together with examples based in the optimization of the synthesis conditions. In the case of non-porous materials, examples of analytical applications, coating of metallic nanoparticles, and SiOx-C materials have been collected.

14.
Sci Technol Adv Mater ; 20(1): 699-709, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275461

RESUMO

Four types of calcined MCM-41 silica nanoparticles, loaded with dyes and capped with different gating ensembles are prepared and characterized. N1 and N2 nanoparticles are loaded with rhodamine 6G and capped with bulky poly(ethylene glycol) derivatives bearing ester groups (1 and 2). N3-N4 nanoparticles are loaded with sulforhodamine B and capped with self-immolative derivatives bearing ester moieties. In the absence of esterase enzyme negligible cargo release from N1, N3 and N4 nanoparticles is observed whereas a remarkable release for N2 is obtained most likely due to the formation of an irregular coating on the outer surface of the nanoparticles. In contrast, a marked delivery is found in N1, N3, and N4 in the presence of esterase enzyme. The delivery rate is related to the hydrophilic/hydrophobic character of the coating shell. The use of hydrophilic poly(ethylene glycol) derivatives as gating ensembles on N1 and N2 enables an easy access of esterase to the ester moieties with subsequent fast cargo release. On the other hand, the presence of a hydrophobic monolayer on N3 and N4 partially hinders esterase enzyme access to the ester groups and the rate of cargo release was decreased.

15.
Chem Commun (Camb) ; 55(41): 5785-5788, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31041959

RESUMO

Mesoporous silica nanoparticles capped with acetylcholinesterase, through boronic ester linkages, selectively release an entrapped cargo in the presence of acetylcholine.

16.
Mol Pharm ; 16(6): 2418-2429, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-30991003

RESUMO

Silica mesoporous microparticles loaded with both rhodamine B fluorophore (S1) or hydrocortisone (S2), and capped with an olsalazine derivative, are prepared and fully characterized. Suspensions of S1 and S2 in water at an acidic and a neutral pH show negligible dye/drug release, yet a notable delivery took place when the reducing agent sodium dithionite is added because of hydrolysis of an azo bond in the capping ensemble. Additionally, olsalazine fragmentation induced 5-aminosalicylic acid (5-ASA) release. In vitro digestion models show that S1 and S2 solids are suitable systems to specifically release a pharmaceutical agent in the colon. In vivo pharmacokinetic studies in rats show a preferential rhodamine B release from S1 in the colon. Moreover, a model of ulcerative colitis is induced in rats by oral administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) solutions, which was also used to prove the efficacy of S2 for colitis treatment. The specific delivery of hydrocortisone and 5-ASA from S2 material to the colon tissue in injured rats markedly lowers the colon/body weight ratio and the clinical activity score. Histological studies showed a remarkable reduction in inflammation, as well as an intensive regeneration of the affected tissues.


Assuntos
Colite/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Dióxido de Silício/química , Animais , Hidrocortisona/química , Masculino , Mesalamina/química , Mesalamina/uso terapêutico , Ratos , Ratos Wistar , Rodaminas/química , Rodaminas/uso terapêutico
17.
Int J Pharm ; 561: 93-101, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30817986

RESUMO

A colon targeted drug delivery system for inflammatory bowel diseases (IBD), consisting in budesonide loaded mesoporous silica microparticles functionalized with a selective azo-molecular gate (M-Bud), has been evaluated for in vivo efficacy. Experimental colitis in male Wistar rats was induced by rectal instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS). M-Bud was orally administered to the rats as a suspension in water. Colon/body weight ratio, clinical activity score, and histological evaluation were used as inflammatory indices to measure the performance of the microparticles. The formulation was compared with a suspension prepared from the commercial drug Entocord®. Statistical analyses of all scores indicate that the controlled release of budesonide in colon from M-Bud showed efficacy similar to that of Entocord in the healing of induced colitis in rats.


Assuntos
Budesonida/uso terapêutico , Colite/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Dióxido de Silício/uso terapêutico , Animais , Compostos Azo/química , Compostos Azo/uso terapêutico , Budesonida/química , Colite/induzido quimicamente , Colite/patologia , Masculino , Ratos , Dióxido de Silício/química , Ácido Trinitrobenzenossulfônico
18.
Nanomaterials (Basel) ; 9(2)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813298

RESUMO

Gold nanoparticles functionalized with resorcinol moieties have been prepared and used for detecting formaldehyde both in solution and gas phases. The detection mechanism is based on the color change of the probe upon the aggregation of the nanoparticles induced by the polymerization of the resorcinol moieties in the presence of formaldehyde. A limit of detection of 0.5 ppm in solution has been determined. The probe can be deployed for the detection of formaldehyde emissions from composite wood boards.

19.
Anal Chim Acta ; 1056: 146-152, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-30797455

RESUMO

A simple and effective colorimetric method for the detection of normetanephrine (NMN), an O-methylated metabolite of norepinephrine, using functionalised gold nanoparticles is described. This metabolite is an important biomarker in the diagnosis of adrenal tumours such as pheocromocytoma or paraganglioma. The colorimetric probe consists of spherical gold nanoparticles (AuNPs) functionalised with two different ligands, which specifically recognize different functional groups in normetanephrine. Thus, a benzaldehyde-terminated ligand was used for the recognition of the amino alcohol moiety in NMN, by forming the corresponding oxazolidine. On the other hand, N-acetyl-cysteine was chosen for the recognition of the phenolic hydroxyl group through the formation of hydrogen bonds. The selective double molecular recognition between the probe and the hydroxyl and the amino-alcohol moieties of normetanephrine led to interparticle-crosslinking aggregation resulting in a change in the color of the solution, from red to blue, which could be observed by naked eye. The probe was highly selective towards normetanephrine and no color changes were observed in the presence of other neurotransmitter metabolites such as homovanillic acid (HVA) (dopamine metabolite), 5-hydroxyindoleacetic acid (5-HIAA) (serotonin metabolite), or other biomolecules present in urine such as glucose (Glc), uric acid (U.A), and urea. Finally, the probe was evaluated in synthetic urine with constituents that mimic human urine, where a limit of detection of 0.5 µM was achieved.


Assuntos
Neoplasias das Glândulas Suprarrenais , Biomarcadores Tumorais/análise , Colorimetria/métodos , Ouro/química , Nanopartículas Metálicas/química , Normetanefrina/análise , Feocromocitoma , Linhagem Celular Tumoral , Humanos , Limite de Detecção , Normetanefrina/urina
20.
Molecules ; 23(10)2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30332750

RESUMO

A new environmentally-friendly, simple, selective and sensitive probe for detecting formaldehyde, based on naturally-occurring compounds, through either colorimetric or fluorescence changes, is described. The probe is able to detect formaldehyde in both solution and the gas phase with limits of detection of 0.24 mM and 0.7 ppm, respectively. The probe has been tested to study formaldehyde emission in contaminated real atmospheres. The supported probe is easy to use and to dispose, and is safe and suitable as an individual chemodosimeter.


Assuntos
Formaldeído/análise , Soluções/análise , Colorimetria , Limite de Detecção , Espectrometria de Fluorescência
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