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1.
Chemistry ; : e202401734, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850206

RESUMEN

A water-soluble prism[5]arene host can form endo-cavity complexes with hydrophilic organic substances in water by displacing frustrated water molecules from its deep cavity. Water molecules structured at both rims of the prismarene host can mediate hydrogen bonding interactions with the guest. Water-mediated hydrogen bonding interactions were invoked here to elucidate the elevated binding affinities and selectivity of the prismarene host toward hydrophilic organic guests. We show that water at the interface of a host-guest complex can act as an extension of the host structure, facilitating the accommodation of neutral guests within the binding site. This study highlights the crucial role of water in facilitating supramolecular interactions between a deep-cavity prismarene host and organic hydrophilic guests in aqueous medium.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 317: 124421, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38759394

RESUMEN

Albumin is undoubtedly the most studied protein thanks to its widespread diffusion and biochemistry; despite its binding ability towards different dyes, provoking dye's colour change, has been exploited for decades for quantification purposes, the joint effect of working pH, ionic strength, and dye's pKa still remains only sporadically discussed. In the present study, the interaction of Bovine Serum Albumin (BSA) with five dyes belonging to the sulfonephthalein group, Bromophenol Blue (BPB, pKa = 3.75), Bromocresol Green (BCG, pKa = 4.42), Chlorophenol Red (CPR, pKa = 5.74), Bromocresol Purple (BCP, pKa = 6.05) and Bromothymol Blue (BTB, pKa = 6.72), is investigated at four working pH values (3.5, 6.0, 7.5 and 9.0) and two ionic strength conditions by UV-Vis spectroscopy. Principal Component Analysis is then applied to rationalize dye behavior upon BSA addition at each pH value and to summarize the protein effect on dyes' spectral features, identifying three general behaviors. The most relevant systems are then submitted to further characterization involving a solution equilibria study aimed at determining conditional binding constants for the selected DSA-dye adducts and fluorescence, CD, and 1H NMR spectroscopy to evaluate the binding effect on the species involved.


Asunto(s)
Colorantes , Albúmina Sérica Bovina , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/metabolismo , Colorantes/química , Bovinos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Animales , Soluciones , Espectrofotometría Ultravioleta , Unión Proteica , Azul de Bromofenol/química , Azul de Bromofenol/metabolismo , Espectrometría de Fluorescencia , Verde de Bromocresol/química , Verde de Bromocresol/metabolismo , Análisis de Componente Principal , Púrpura de Bromocresol/química , Púrpura de Bromocresol/metabolismo
3.
Medicina (Kaunas) ; 60(5)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38792876

RESUMEN

Background and Objectives: Serum alpha-fetoprotein (AFP) is a recognized affordable oncological marker in patients with hepatocellular carcinoma (HCC). However, AFP's prognostic role has been assessed mainly after specific treatments, and no unanimously recognized cut-offs have been identified. The aim of this study is to investigate the prognostic role of different basal AFP cut-offs on survival and HCC course. Materials and Methods: In this single-center, retrospective study, all patients newly diagnosed with HCC between January 2009 and December 2021 were prospectively enrolled. Only patients suitable for curative HCC treatments were included in the analyses. Patients were stratified according to AFP cut-offs of 20, 200, 400, and 1000 ng/mL, which were correlated with survival outcomes and clinical parameters. Results: A total of 266 patients were analyzed, with a median follow-up time of 41.5 months. Median overall survival (OS) of all cohort was 43 months. At the multivariate Cox-regression analysis, AFP value ≥ 1000 ng/mL correlated with impaired OS (1-year OS: 67% vs. 88%, 5-year OS: 1% vs. 43%; p = 0.005); other risk factors were tumor dimension ≥ 5 cm (HR 1.73; p = 0.002), Child-Pugh class B-C (HR 1.72; p = 0.002), BCLC stage A (vs. 0) (HR 2.4; p = 0.011), and malignant portal vein thrombosis (HR 2.57; p = 0.007). AFP ≥ 1000 ng/mL was also associated with a reduced recurrence-free survival (HR 2.0; p = 0.038), while starting from AFP ≥ 20 ng/mL, a correlation with development of HCC metastases over time (HR 3.5; p = 0.002) was seen. AFP values ≥ 20 ng/mL significantly correlated with tumor size and higher histological grading; starting from AFP values ≥ 400 ng/mL, a significant correlation with Child-Pugh class B-C and female gender was also observed. Conclusions: Basal AFP correlates with relevant outcomes in patients with HCC. It could help identify patients at a higher risk of worse prognosis who might benefit from personalized surveillance and treatment programs. Prospective studies are needed to confirm these results.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , alfa-Fetoproteínas , Humanos , Carcinoma Hepatocelular/sangre , alfa-Fetoproteínas/análisis , Neoplasias Hepáticas/sangre , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Pronóstico , Anciano , Biomarcadores de Tumor/sangre , Adulto , Modelos de Riesgos Proporcionales , Análisis de Supervivencia
4.
Carbohydr Polym ; 328: 121698, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38220321

RESUMEN

Iodine is a vital microelement and a powerful antiseptic with a rapid and broad spectrum of action. The development of iodophor compounds to improve the solubility and stability of iodine is still challenging. Here, we report the synthesis of a novel cationic ß-cyclodextrin bearing a choline-like pendant (ß-CD-Chol) designed to complex and deliver iodine to bacterial cells. The characterization of ß-CD-Chol and the investigation of the inclusion complex with iodine were performed by NMR spectroscopy, mass spectrometry, UV-vis spectrophotometry, isothermal titration calorimetry, and dynamic light scattering. The functionalization with the positively charged unit conferred improved water-solubility, mucoadhesivity, and iodine complexation efficiency to the ß-CD scaffold. The water-soluble ß-CD-Chol/iodine complex efficiently formed both in solution and by solid-vapor reaction. The solid complex exhibited a significant stability for months. Iodine release from the inclusion complex was satisfactory and the bactericidal activity was proved against a Staphylococcus epidermidis strain. The absence of cytotoxicity tested on human keratinocytes and the improved mucoadhesivity make ß-CD-Chol a promising drug delivery system and an appealing iodophor candidate for iodine-based antisepsis including mucosa disinfection.


Asunto(s)
Yodo , beta-Ciclodextrinas , Humanos , Colina , beta-Ciclodextrinas/química , Yodo/farmacología , Yodo/química , Solubilidad , Antibacterianos/farmacología , Yodóforos , Agua/química , Rastreo Diferencial de Calorimetría , 2-Hidroxipropil-beta-Ciclodextrina/química
5.
Cancers (Basel) ; 15(22)2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38001656

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death. Abdominal ultrasound (US) is by far the most widely used first-level exam for the diagnosis of HCC. We aimed to assess whether different ultrasound patterns were related to tumor prognosis. METHODS: We retrospectively reviewed all patients with a new diagnosis of HCC (single nodule) and undergoing radiofrequency thermal ablation (RFTA) at our clinic between January 2009 and December 2021. Patients were classified according to four HCC ultrasound patterns: 1A, single capsulated nodule; 1B, well capsulated intra-node nodule; 1C, cluster consisting of capsulated nodules; and 2, non-capsulated nodule. RESULTS: 149 patients were analysed; median follow-up time was 43 months. US patterns 1A (32.9%) and 1B (61.1%) were the most commonly seen. Median overall survival (OS) and recurrence-free survival (RFS) from RFTA were 54 months (95% CI, 42-66) and 22 months (95% CI, 12-32), respectively. Pattern 1A showed the best OS. Compared to pattern 1A, 1B was independently associated with worse OS (51 months (95% CI, 34-68) vs. 46 months (95% CI, 18-62)) and RFS (34 months (95% CI, 27-41) vs. 18 months (95% CI, 12-24)). Patterns 1C and 2 were associated with worse RFS compared to 1A, while no difference was seen for OS. Among baseline clinical variables, pattern 1B exhibited higher histological grade (p = 0.048) and tumor dimension (p = 0.034) compared to pattern 1A. CONCLUSIONS: Our findings demonstrate that different US patterns correlate with different survival outcomes and tumor behavior in patients with HCC. Prospective studies are needed to confirm these results.

6.
Molecules ; 28(14)2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37513453

RESUMEN

The development of novel drug delivery systems (DDSs) with promising antibacterial properties is essential for facing the emergency of increasing resistance to antimicrobial agents. The antibacterial features of quercetin and its metal complexes have been broadly investigated. However, several drawbacks affect their activity and effectiveness. In this work, we propose a DDS based on a pH-responsive cobalt(II)-coordinated assembly containing quercetin and polyacrylic acid. This system is suggested to trigger the release of the model drug in a pH-dependent mode by exploiting the localized acidic environment at the bacterial infection sites under anaerobic conditions. The delivery system has been designed by accurately examining the species and the multiple equilibria occurring in solution among the assembly components. The formation of cobalt(II) complexes with quercetin in the absence or presence of the pH-responsive polyacrylic acid was investigated in buffered aqueous solution at pH 7.4 using spectrophotometric (UV-Vis) and calorimetric (ITC) techniques. The determined binding affinities and thermodynamic parameters that resulted are essential for the development of a DDS with improved binding and release capabilities. Furthermore, the affinity of the polymer-cobalt(II) complex toward the model antimicrobial flavonoid was explored at the solid-liquid interface by quartz crystal microbalance (QCM-D) experiments, which provided marked evidence for drug loading and release under pH control.


Asunto(s)
Complejos de Coordinación , Quercetina , Quercetina/farmacología , Cobalto/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Antibacterianos/farmacología , Antibacterianos/química , Concentración de Iones de Hidrógeno
7.
Medicina (Kaunas) ; 59(3)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36984637

RESUMEN

Background: Obesity is a chronic disease that impairs quality of life and leads to several comorbidities. When conservative therapies fail, bariatric surgical options such as Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are the most effective therapies to induce persistent weight loss. Over the last two decades, bariatric endoscopy has become a valid alternative to surgery in specific settings. Primary bariatric endoscopic therapies: Restrictive gastric procedures, such as intragastric balloons (IGBs) and endoscopic gastroplasty, have been shown to be effective in inducing weight loss compared to diet modifications alone. Endoscopic gastroplasty is usually superior to IGBs in maintaining weight loss in the long-term period, whereas IGBs have an established role as a bridge-to-surgery approach in severely obese patients. IGBs in a minority of patients could be poorly tolerated and require early removal. More recently, novel endoscopic systems have been developed with the combined purpose of inducing weight loss and improving metabolic conditions. Duodenal mucosal resurfacing demonstrated efficacy in this field in its early trials: significant reduction from baseline of HbA1c values and a modest reduction of body weight were observed. Other endoscopic malabsorptive have been developed but need more evidence. For example, a pivotal trial on duodenojejunal bypasses was stopped due to the high rate of severe adverse events (hepatic abscesses). Optimization of these more recent malabsorptive endoscopic procedures could expand the plethora of bariatric patients that could be treated with the intention of improving their metabolic conditions. Revisional bariatric therapies: Weight regain may occur in up to one third of patients after bariatric surgery. Different endoscopic procedures are currently performed after both RYGB and SG in order to modulate post-surgical anatomy. The application of argon plasma coagulation associated with endoscopic full-thickness suturing systems (APC-TORe) and Re-EndoSleeve have shown to be the most effective endoscopic treatments after RYGB and SG, respectively. Both procedures are usually well tolerated and have a very low risk of stricture. However, APC-TORe may sometimes require more than one session to obtain adequate final results. The aim of this review is to explore all the currently available primary and revisional endoscopic bariatric therapies focusing on their efficacy and safety and their potential application in clinical practice.


Asunto(s)
Derivación Gástrica , Enfermedades Metabólicas , Obesidad Mórbida , Humanos , Obesidad Mórbida/cirugía , Calidad de Vida , Reoperación/métodos , Endoscopía/métodos , Derivación Gástrica/efectos adversos , Derivación Gástrica/métodos , Obesidad/cirugía , Obesidad/etiología , Resultado del Tratamiento , Pérdida de Peso , Estudios Retrospectivos
8.
Nanomaterials (Basel) ; 13(2)2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36678039

RESUMEN

Povidone iodine (PVPI) is an antiseptic widely used against a broad spectrum of pathogens. However, undesired side-effects are still associated with PVPI treatment due to the irritant effect of iodine. Reducing the concentration of a PVPI formulation could provide safer and more friendly formulations, for routine use and applications in very delicate organs such as the eye. However, managing the storage of a low-concentration solution of PVPI is challenging due to the high iodine volatility. In this study, we demonstrated that an amphiphilic p-sulfonato-calix[4]arene derivative forming micelles (SC4OC6) improves the stability of a 0.1% PVPI aqueous buffered solution. UV-vis and NMR spectra as well as dynamic and electrophoretic light scattering measurements showed that SC4OC6 establishes non-covalent supramolecular interactions with PVPI, resulting in the formation of nanoaggregates with a negatively charged surface. Isothermal titration calorimetry provided the aggregation parameters and evidenced that the formation of the supramolecular assembly is an enthalpically favored process. The interaction of SC4OC6 with PVPI enhances the iodine retention and stability of the solution without affecting the rapid and effective bactericidal activity of PVPI, as demonstrated by a time-killing assay with Staphylococcus epidermidis.

9.
Org Lett ; 24(14): 2711-2715, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35389649

RESUMEN

The synthesis of water-soluble prism[n]arenes (n = 5 and 6) bearing anionic carboxylato groups on the rims is described. The binding properties of this novel class of water-soluble hosts are studied by nuclear magnetic resonance and calorimetry. The complexation of singly and doubly charged ammonium guests with the more rigid pentamer is enthalpically driven by secondary interactions, while the thermodynamic fingerprint for the larger hexamer reveals driving forces that strongly depend on the guest charge and/or size.

10.
Biomolecules ; 12(3)2022 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-35327600

RESUMEN

Metals and metal-based compounds have many implications in biological systems. They are involved in cellular functions, employed in the formation of metal-based drugs and present as pollutants in aqueous systems, with toxic effects for living organisms. Amphiphilic molecules also play important roles in the above bio-related fields as models of membranes, nanocarriers for drug delivery and bioremediating agents. Despite the interest in complex systems involving both metal species and surfactant aggregates, there is still insufficient knowledge regarding the quantitative aspects at the basis of their binding interactions, which are crucial for extensive comprehension of their behavior in solution. Only a few papers have reported quantitative analyses of the thermodynamic, kinetic, speciation and binding features of metal-based compounds and amphiphilic aggregates, and no literature review has yet addressed the quantitative study of these complexes. Here, we summarize and critically discuss the recent contributions to the quantitative investigation of the interactions of metal-based systems with assemblies made of amphiphilic molecules by calorimetric, spectrophotometric and computational techniques, emphasizing the unique picture and parameters that such an analytical approach may provide, to support a deep understanding and beneficial use of these systems for several applications.


Asunto(s)
Complejos de Coordinación , Calorimetría/métodos , Cinética , Metales/química , Termodinámica
11.
Nanomaterials (Basel) ; 11(11)2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34835694

RESUMEN

The co-delivery of anticancer drugs into tumor cells by a nanocarrier may provide a new paradigm in chemotherapy. Temozolomide and curcumin are anticancer drugs with a synergistic effect in the treatment of multiform glioblastoma. In this study, the entrapment and co-entrapment of temozolomide and curcumin in a p-sulfonato-calix[4]arene nanoparticle was investigated by NMR spectroscopy, UV-vis spectrophotometry, isothermal titration calorimetry, and dynamic light scattering. Critical micellar concentration, nanoparticle size, zeta potential, drug loading percentage, and thermodynamic parameters were all consistent with a drug delivery system. Our data showed that temozolomide is hosted in the cavity of the calix[4]arene building blocks while curcumin is entrapped within the nanoparticle. Isothermal titration calorimetry evidenced that drug complexation and entrapment are entropy driven processes. The loading in the calixarene-based nanocontainer enhanced the solubility and half-life of both drugs, whose medicinal efficacy is affected by low solubility and rapid degradation. The calixarene-based nanocontainer appears to be a promising new candidate for nanocarrier-based drug combination therapy for glioblastoma.

12.
Chemistry ; 27(70): 17669-17675, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34637566

RESUMEN

Series of lanthanide-containing metallic coordination complexes are frequently presented as structurally analogous, due to the similar chemical and coordinative properties of the lanthanides. In the case of chiral (LnIII [15-MC Cu II N(L-pheHA) -5])3+ metallacrowns (MCs), which are well established supramolecular hosts, the formation of dimers templated by a dicarboxylate guest (muconate) in solution of neutral pH is herein shown to have a unique dependence on the identity of the MC's central lanthanide. Calorimetric data and nuclear magnetic resonance diffusion studies demonstrate that MCs containing larger or smaller lanthanides as the central metal only form monomeric host-guest complexes whereas analogues with intermediate lanthanides (for example, Eu, Gd, Dy) participate in formation of dimeric host-guest-host compartments. The driving force for the dimerization event across the series is thought to be a competition between formation of highly stable MCs (larger lanthanides) and optimally linked bridging guests (smaller lanthanides).


Asunto(s)
Complejos de Coordinación , Elementos de la Serie de los Lantanoides , Calorimetría , Dimerización , Concentración de Iones de Hidrógeno
13.
J Environ Sci (China) ; 94: 100-110, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32563473

RESUMEN

In recent years, the contamination of water by arsenic reached alarming levels in many countries of the world, attracting the interest of many researchers engaged in testing methodologies able to remove this harmful pollutant. An important aspect that must be taken into consideration is the possibility to find arsenic in different chemical forms which could require different approaches for its removal. At this aim, a speciation analysis appears to be crucial for better understanding the behavior of arsenic species in aqueous solutions, especially in presence of compounds with marked chelating properties. Phosphonates can be identified as good sequestering agents and, at this purpose, this manuscript intends to investigate the interaction of As(III) with three phosphonic acids derived from nitrilotriacetic acid (NTA) by replacements of one (N-(Phosphonomethyl) iminodiacetic acid, NTAP), two (N,N-Bis-(phosphonomethyl) glycine, NTA2P) and three (Nitrilotri(methylphosphonic acid), NTA3P) carboxylic groups with the same number of phosphonate groups. An in-depth potentiometric and calorimetric investigation allowed to determine speciation models featured by simple ML, MLHi and ML(OH) species. A complete thermodynamic characterization of the systems is reported together with the definition of coordination mode by mass spectrometry measurements. On the light of the speciation models, the possibility of using these ligands in arsenic removal techniques was assessed by determining the pL0.5 (the concentration of ligand able to remove the 50% of metal ion present in trace). All ligands show a good sequestering ability, in particular under the conditions of fresh water, following the trend NTA3P > NTA2P > NTAP.


Asunto(s)
Organofosfonatos , Agua , Quelantes , Ligandos , Termodinámica
14.
Front Chem ; 8: 626467, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33520941

RESUMEN

The search for novel surfactants or drug delivery systems able to improve the performance of old-generation antibiotics is a topic of great interest. Self-assembling amphiphilic calix[4]arene derivatives provide well-defined nanostructured systems that exhibit promising features for antibiotics delivery. In this work, we investigated the capability of two micellar polycationic calix[4]arene derivatives to recognize and host ofloxacin, chloramphenicol, or tetracycline in neutral aqueous solution. The formation of the nanoaggregates and the host-guest equilibria were examined by nano-isothermal titration calorimetry, dynamic light scattering, and mono- and bi-dimensional NMR. The thermodynamic characterization revealed that the calix[4]arene-based micellar aggregates are able to effectively entrap the model antibiotics and enabled the determination of both the species and the driving forces for the molecular recognition process. Indeed, the formation of the chloramphenicol-micelle adduct was found to be enthalpy driven, whereas entropy drives the formation of the adducts with both ofloxacin and tetracycline. NMR spectra corroborated ITC data about the positioning of the antibiotics in the calixarene nanoaggregates.

15.
Molecules ; 24(20)2019 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-31635063

RESUMEN

Hydroxypyrone derivatives have a good bioavailability in rats and mice and have been used in drug development. Moreover, they show chelating properties towards vanadyl cation that could be used in insulin-mimetic compound development. In this work, the formation of coordination compounds of oxovanadium(IV) with four kojic acid (5-hydroxy-2-(hydroxymethyl)-4-pyrone) derivatives was studied. The synthetized studied ligands (S2, S3, S4, and SC) have two or three kojic acid units linked through diamines or tris(2-aminoethyl)amine chains, respectively. The chemical systems were studied by potentiometry (25 °C, ionic strength 0.1 mol L-1 with KCl), and UV-visible and EPR spectroscopy. The experimental data were analyzed by a thermodynamic and a chemometric (Multivariate Curve Resolution-Alternating Least Squares) approach. Chemical coordination models were proposed, together with the species formation constants and the pure estimated UV-vis and EPR spectra. In all systems, the coordination of the oxovanadium(IV) starts already under acidic conditions (the cation is totally bound at pH higher than 3-4) and the metal species remain stable even at pH 8. Ligands S3, S4, and SC form three coordination species. Two of them are probably due to the successive insertion of the kojate units in the coordination shell, whereas the third is most likely a hydrolytic species.


Asunto(s)
Complejos de Coordinación/síntesis química , Pironas/química , Vanadatos/química , Complejos de Coordinación/química , Espectroscopía de Resonancia por Spin del Electrón , Ligandos , Estructura Molecular
16.
J Inorg Biochem ; 180: 89-100, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29247871

RESUMEN

Copper(II) complexes with 8-hydroxyquinoline (8-HQ) and two 8-HQ derivatives, namely clioquinol (CQ) and 5,7-dichloro-2-[(dimethylamino)methyl]quinolin-8-ol (PBT2), were investigated in organic and, where feasible, in aqueous solutions. This class of compounds is of particular interest in neurological disorders since they may act as metal-protein attenuating compounds and may help redistributing metal ions and restoring intracellular metal reserves, which are often perturbed in neurological patients. Several techniques, like potentiometry, UV-Vis absorption, electron paramagnetic resonance (EPR), cyclic voltammetry and electrospray ionisation-mass spectrometry (ESI-MS), were used to obtain information on both the formation of copper(II) complexes in solution as well as on the structure of their species. Multi-wavelength treatment of UV-Vis data clearly indicated the formation of both [Cu(PBT2)]+ and [Cu(PBT2)2] species; the speciation was also supported by ESI-MS data. The EPR results showed that the mono- and bis-copper(II) complexes with PBT2 have square-based pyramidal structures while the bis-copper (II) complexes with CQ or 8-HQ have square-planar o pseudo-octahedral geometries. The formation of copper(II) ternary complexes with 8-HQ, CQ and PBT2 and some selected neurotransmitters (glycine, glutamate and histidine) is also reported. Except for the copper(II) ternary complex with PBT2 and His, almost all ternary complexes have molecular geometries, which are not different from those of the bis-complexes. Interestingly the ternary copper(II) complexes, containing CQ, 8-HQ and PBT2 and glycine, glutamate or histidine turned out to be more soluble in aqueous solution than their binary complexes with parent 8-HQ derivatives; the copper(II) complexes can also be reduced more easily than their parent bis-complexes.


Asunto(s)
Aminoácidos/química , Cobre/química , Oxiquinolina/química , Complejos de Coordinación/química , Complejos de Coordinación/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Glutatión/química , Neurotransmisores/química , Neurotransmisores/metabolismo , Pliegue de Proteína , Soluciones , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta , Termogravimetría , Respuesta de Proteína Desplegada
17.
Metallomics ; 9(10): 1439-1446, 2017 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-28932850

RESUMEN

Proliferation and programmed cell death are tightly correlated with the ubiquitin-proteasome system (UPS). Alterations in the UPS may be implicated in pathological conditions such as the proteasome over-activity in cancer cells. Mounting evidence indicates that many types of actively proliferating malignant cells are more sensitive to proteasome inhibition than normal cells, and therefore UPS inhibitors are actively pursued as anticancer agents. The approval of the proteasome inhibitor drug bortezomib for the treatment of myeloma and lymphoma further highlights the need for UPS inhibitors. Recent studies have suggested that clioquinol and 5-amino-8-hydroxyquinoline can inhibit proteasome activity and induce apoptosis in human cancer cells. As for clioquinol, a copper-dependent and -independent mechanism has been proposed to explain the inhibition of the proteasome whereas the activity of 5-amino-8-hydroxyquinoline has not been explored in the presence of copper(ii) ions. Herein, we investigated the biological activity of some 8-hydroxyquinolines by using human ovarian (A2780) and lung (A549) cancer cells. The effect of copper(ii) on the activity of these compounds was also evaluated. The investigated systems inhibit the chymotrypsin-like activity of the proteasome and induce growth inhibition and apoptosis in a concentration-dependent manner. Copper(ii) ions increase the activity of 8-hydroxyquinoline derivatives except in the case of 5-amino-8-hydroxyquinoline. This study suggests the great potential of amino- and chloro-8-hydroxyquinolines as anticancer agents. Furthermore, it clarifies some aspects concerning the activity of 5-amino-8-hydroxyquinoline, which has been previously proposed as a proteasome inhibitor capable of overcoming resistance to bortezomib.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Cobre/química , Hidroxiquinolinas/farmacología , Neoplasias/tratamiento farmacológico , Inhibidores de Proteasoma/farmacología , Antineoplásicos/química , Femenino , Humanos , Hidroxiquinolinas/química , Complejo de la Endopetidasa Proteasomal/química , Inhibidores de Proteasoma/química , Células Tumorales Cultivadas , Ubiquitinación
18.
Chemistry ; 23(66): 16813-16818, 2017 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-28898458

RESUMEN

The supramolecular assembly [Ga4 L6 ]12- acts as a nanoscale flask to mediate the reactivity of encapsulated reactive guests and also functions as a catalyst to carry out enzyme-like chemical transformations. The guest binding to the interior cavity and exterior of this host is difficult to untangle because multiple equilibria occur in solution, and only when refining simultaneously data obtained from different techniques, such as NMR, UV/Vis, and calorimetry, can the accurate solution thermodynamics of these host-guest systems be determined. This study reports the driving forces for the inclusion and stepwise exterior guest binding of different aliphatic quaternary ammonium guests to the [Ga4 L6 ]12- assembly. Encapsulation into the host cavity was found to be an entropy-driven process, whereas exterior ion association is driven either by enthalpically favorable attractive forces or by the entropy gain due to desolvation, depending on guest size and character. The analysis of the energetics of reaction may help predicting and understanding the intimate role and contribution of the transition state in those rate-accelerated reactions involving this supramolecular assembly as an enzyme-like molecular flask.

19.
Eur J Intern Med ; 46: 61-65, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28793969

RESUMEN

BACKGROUND: Dyspnea is one of the most frequent causes of admission in Internal Medicine wards, leading to a sizeable utilization of medical resources. STUDY DESIGN AND METHODS: The role of bedside lung ultrasound (LUS) was evaluated in 130 consecutive patients (age: 81±9years), in whom blindly collected LUS results were compared with data obtained by clinical examination, medical history, blood analysis, and chest X-ray. Dyspnea etiology was classified as "cardiac" (n=80), "respiratory" (n=36) or "mixed" (n=14), according to the discharge diagnosis (congestive heart failure either alone [n=80] or associated with pneumonia [n=14], pneumonia [n=24], and obstructive disventilatory syndrome [n=12]). An 8-window LUS protocol was applied to evaluate B-line distribution, "interstitial syndrome" pattern, pleural effusion and images of static or dynamic air bronchogram/focal parenchymal consolidation. RESULTS: The presence of a generalized "interstitial syndrome" at the initial LUS evaluation allowed to discriminate "cardiac" from "pulmonary" Dyspnea with high sensitivity (93.75%; confidence intervals: 86.01%-97.94%) and specificity (86.11%; 70.50%-95.33%). Positive and negative predictive values were 93.76% (86.03%-97.94%) and 86.09% (70.47%-95.32%), respectively. Moreover, LUS diagnostic accuracy for the diagnosis of pneumonia was not inferior to that of chest X-ray. CONCLUSIONS: Bedside LUS evaluation contributes with high sensitivity and specificity to the differential diagnosis of Dyspnea. This holds true not only in the emergency setting, but also in the sub-acute Internal Medicine arena. A wider use of this portable technique in our wards is warranted.


Asunto(s)
Disnea/diagnóstico por imagen , Disnea/etiología , Pulmón/diagnóstico por imagen , Sistemas de Atención de Punto , Ultrasonografía , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Medicina Interna , Italia , Masculino , Estudios Prospectivos , Análisis de Regresión , Sensibilidad y Especificidad
20.
J Colloid Interface Sci ; 506: 532-542, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28756320

RESUMEN

The actual surface termination and lateral size of a nanomaterial is crucial in its interaction with biomolecules at the aqueous interface. Graphene oxide (GO) nanosheets have been demonstrated as promising nanoplatform for both diagnostic and therapeutic applications. To this respect, 'smart' GO nanocarriers have been obtained by the surface functionalisation with polymers sensitive, e.g., to pH, as the polyacrylate (PAA) case. In this work, hybrid GO/PAA samples prepared respectively at low (GOPAAthin) or high (GOPAAthick) monomer grafting ratio, were scrutinised both theoretically, by molecular dynamic calculations, and experimentally by a multitechnique approach, including spectroscopic (UV-visible, fluorescence, Raman, Attenuated-total reflectance-Fourier transformed infrared and X-ray photoelectron spectroscopies), spectrometric (time-of-flight secondary ion and electrospray ionisation mass spectrometries) and microscopic (atomic force and confocal microscopies) methods. The actual surface termination, evaluated in terms of the relative ratio between polar and dispersive groups at the surface of the GO/polymer systems, was found to correlate with the average orientation of hydrophilic/hydrophobic domains of albumin, used as model protein. Moreover, the comparison among GO, GO-PAAthin and GO-PAAthick in the optical response at the interface with aqueous solutions, both at acid and at physiological pH, showed that the hybrid GO-polymer platform could be suitable not only to exploit a pH-triggered drug release but also for a modulation of the GO intrinsic emission properties. Energy transfer experiments on the GO/polymer oxide/fluorescein-labelled albumin/doxorubicin assembly showed significant differences for GO and GO-PAA samples, thus demonstrating the occurrence of different electronic processes at the hybrid nano-bio-interfaces. Confocal microscopy studies of cellular uptake in neuroblastoma cells confirmed the promising potentialities of the developed nanoplatform for applications at the biointerface.


Asunto(s)
Resinas Acrílicas/química , Portadores de Fármacos/química , Grafito/química , Nanoestructuras/química , Óxidos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Liberación de Fármacos , Fluoresceína/química , Humanos , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Polimerizacion , Propiedades de Superficie
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