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1.
Nat Immunol ; 25(4): 633-643, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38486021

RESUMEN

Vaccines have reduced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) morbidity and mortality, yet emerging variants challenge their effectiveness. The prevailing approach to updating vaccines targets the antibody response, operating under the presumption that it is the primary defense mechanism following vaccination or infection. This perspective, however, can overlook the role of T cells, particularly when antibody levels are low or absent. Here we show, through studies in mouse models lacking antibodies but maintaining functional B cells and lymphoid organs, that immunity conferred by prior infection or mRNA vaccination can protect against SARS-CoV-2 challenge independently of antibodies. Our findings, using three distinct models inclusive of a novel human/mouse ACE2 hybrid, highlight that CD8+ T cells are essential for combating severe infections, whereas CD4+ T cells contribute to managing milder cases, with interferon-γ having an important function in this antibody-independent defense. These findings highlight the importance of T cell responses in vaccine development, urging a broader perspective on protective immunity beyond just antibodies.


Asunto(s)
COVID-19 , Vacunas , Humanos , Animales , Ratones , SARS-CoV-2 , Linfocitos T CD8-positivos , COVID-19/prevención & control , Anticuerpos , Vacunación , Anticuerpos Antivirales , Anticuerpos Neutralizantes
2.
Nat Commun ; 15(1): 1201, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38331917

RESUMEN

Chemokine heterodimers activate or dampen their cognate receptors during inflammation. The CXCL12 chemokine forms with the fully reduced (fr) alarmin HMGB1 a physiologically relevant heterocomplex (frHMGB1•CXCL12) that synergically promotes the inflammatory response elicited by the G-protein coupled receptor CXCR4. The molecular details of complex formation were still elusive. Here we show by an integrated structural approach that frHMGB1•CXCL12 is a fuzzy heterocomplex. Unlike previous assumptions, frHMGB1 and CXCL12 form a dynamic equimolar assembly, with structured and unstructured frHMGB1 regions recognizing the CXCL12 dimerization surface. We uncover an unexpected role of the acidic intrinsically disordered region (IDR) of HMGB1 in heterocomplex formation and its binding to CXCR4 on the cell surface. Our work shows that the interaction of frHMGB1 with CXCL12 diverges from the classical rigid heterophilic chemokines dimerization. Simultaneous interference with multiple interactions within frHMGB1•CXCL12 might offer pharmacological strategies against inflammatory conditions.


Asunto(s)
Quimiocina CXCL12 , Proteína HMGB1 , Humanos , Quimiocina CXCL12/metabolismo , Proteína HMGB1/metabolismo , Receptores CXCR4/metabolismo , Inflamación , Transducción de Señal
4.
iScience ; 26(9): 107480, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37636075

RESUMEN

Prions are deadly infectious agents made of PrPSc, a misfolded variant of the cellular prion protein (PrPC) which self-propagates by inducing misfolding of native PrPC. PrPSc can adopt different pathogenic conformations (prion strains), which can be resistant to potential drugs, or acquire drug resistance, hampering the development of effective therapies. We identified Zn(II)-BnPyP, a tetracationic porphyrin that binds to distinct domains of native PrPC, eliciting a dual anti-prion effect. Zn(II)-BnPyP binding to a C-terminal pocket destabilizes the native PrPC fold, hindering conversion to PrPSc; Zn(II)-BnPyP binding to the flexible N-terminal tail disrupts N- to C-terminal interactions, triggering PrPC endocytosis and lysosomal degradation, thus reducing the substrate for PrPSc generation. Zn(II)-BnPyP inhibits propagation of different prion strains in vitro, in neuronal cells and organotypic brain cultures. These results identify a PrPC-targeting compound with an unprecedented dual mechanism of action which might be exploited to achieve anti-prion effects without engendering drug resistance.

5.
Mol Med ; 28(1): 108, 2022 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-36071400

RESUMEN

BACKGROUND: High-mobility group box 1 protein (HMGB1) is an ubiquitous nuclear protein that once released in the extracellular space acts as a Damage Associated Molecular Pattern and promotes inflammation. HMGB1 is significantly elevated during Pseudomonas aeruginosa infections and has a clinical relevance in respiratory diseases such as Cystic Fibrosis (CF). Salicylates are HMGB1 inhibitors. To address pharmacological inhibition of HMGB1 with small molecules, we explored the therapeutic potential of pamoic acid (PAM), a salicylate with limited ability to cross epithelial barriers. METHODS: PAM binding to HMGB1 and CXCL12 was tested by Nuclear Magnetic Resonance Spectroscopy using chemical shift perturbation methods, and inhibition of HMGB1·CXCL12-dependent chemotaxis was investigated by cell migration experiments. Aerosol delivery of PAM, with single or repeated administrations, was tested in murine models of acute and chronic P. aeruginosa pulmonary infection in C57Bl/6NCrlBR mice. PAM efficacy was evaluated by read-outs including weight loss, bacterial load and inflammatory response in lung and bronco-alveolar lavage fluid. RESULTS: Our data and three-dimensional models show that PAM is a direct ligand of both HMGB1 and CXCL12. We also showed that PAM is able to interfere with heterocomplex formation and the related chemotaxis in vitro. Importantly, PAM treatment by aerosol was effective in reducing acute and chronic airway murine inflammation and damage induced by P. aeruginosa. The results indicated that PAM reduces leukocyte recruitment in the airways, in particular neutrophils, suggesting an impaired in vivo chemotaxis. This was associated with decreased myeloperoxidase and neutrophil elastase levels. Modestly increased bacterial burdens were recorded with single administration of PAM in acute infection; however, repeated administration in chronic infection did not affect bacterial burdens, indicating that the interference of PAM with the immune system has a limited risk of pulmonary exacerbation. CONCLUSIONS: This work established the efficacy of treating inflammation in chronic respiratory diseases, including bacterial infections, by topical delivery in the lung of PAM, an inhibitor of HMGB1.


Asunto(s)
Quimiocina CXCL12 , Proteína HMGB1 , Naftoles , Neumonía Bacteriana , Animales , Quimiocina CXCL12/antagonistas & inhibidores , Quimiotaxis/efectos de los fármacos , Modelos Animales de Enfermedad , Proteína HMGB1/antagonistas & inhibidores , Inflamación/tratamiento farmacológico , Inflamación/patología , Ratones , Ratones Endogámicos C57BL , Naftoles/farmacología , Neumonía Bacteriana/tratamiento farmacológico , Pseudomonas aeruginosa/metabolismo
6.
Animals (Basel) ; 11(4)2021 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33917785

RESUMEN

Dairy products play a significant role in the human diet, but they are often associated with high freshwater resource depletion. In Italy, the dairy sector represents more than 12% of the total turnover of the agri-food sector. Trentino Alto Adige is the first Italian region in terms of number of dairy farms, but it does not register a quantitatively consistent dairy production. Notwithstanding, it is characterized mostly by small-scale farms whose strengths are the Protected Designations of Origin and typical mountain productions. The present study aims at: (i) accounting for the virtual water VW of the main dairy products (milk, butter and cheese) produced in Trentino Alto Adige; (ii) estimating the renewable water resources based on the water flow assessment of the study area; (iii) assessing water sustainability comparing the virtual water consumption of the dairy sector at a regional level to the water availability. The findings show that the consumptive virtual water related to dairy production represents about 1% of the water availability in Trentino Alto Adige. Italy's domestic dairy production is expanding to meet the growing demand, but the expansion of dairy farming in water-stressed regions should be avoided, preferring instead suitable mountain regions where small-scale farms represent a lively entrepreneurial substrate.

7.
Food Control ; 123: 107839, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33424138

RESUMEN

The spread of COVID-19 has not only led to many deaths but also to social and economic downturn globally. The study represents an exhaustive compilation of relevant macroeconomic data regarding the status of the agri-food sector from a demand side perspective and an overview of the food product producer and consumer prices after the shock. Its main purpose is to assess the resilience level of the agri-food sector to the coronavirus pandemic, analyzing its effect on commodity prices and focusing on the supply and value chain. The results highlight that fresh and perishable products, whose production or harvest took place during the first wave of COVID-19, have suffered price level effects, while storable products have not registered significant impacts. This phenomenon is mainly due to the vulnerability of the harvest and production phases, which affected fresh and perishable products supply, and to the resilience of transports and logistics, which instead ensured the supply of storable products to the final consumer. Especially in case of future pandemic waves, the implications and information deriving from the present analysis could support researchers, policy makers and managers, serving as an assessment tool to build suitable strategies for the whole agri-food supply chain and thus ensure sector resilience during these unprecedented times.

8.
Front Chem ; 8: 598710, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33324614

RESUMEN

HMGB1 is a key molecule that both triggers and sustains inflammation following infection or injury, and is involved in a large number of pathologies, including cancer. HMGB1 participates in the recruitment of inflammatory cells, forming a heterocomplex with the chemokine CXCL12 (HMGB1·CXCL12), thereby activating the G-protein coupled receptor CXCR4. Thus, identification of molecules that disrupt this heterocomplex can offer novel pharmacological opportunities to treat inflammation-related diseases. To identify new HMGB1·CXCL12 inhibitors we have performed a study on the ligandability of the single HMG boxes of HMGB1 followed by a virtual screening campaign on both HMG boxes using Zbc Drugs and three different docking programs (Glide, AutoDock Vina, and AutoDock 4.2.6). The best poses in terms of scoring functions, visual inspection, and predicted ADME properties were further filtered according to a pharmacophore model based on known HMGB1 binders and clustered according to their structures. Eight compounds representative of the clusters were tested for HMGB1 binding by NMR. We identified 5,5'-methylenedi-2,3-cresotic acid (2a) as a binder of both HMGB1 and CXCL12; 2a also targets the HMGB1·CXCL12 heterocomplex. In cell migration assays 2a inhibited the chemotactic activity of HMGB1·CXCL12 with IC50 in the subnanomolar range, the best documented up to now. These results pave the way for future structure activity relationship studies to optimize the pharmacological targeting of HMGB1·CXCL12 for anti-inflammatory purposes.

9.
Artículo en Inglés | MEDLINE | ID: mdl-32560272

RESUMEN

The problem of food insecurity is growing across the world, including economically developed countries. In Europe, the question is not just about the total supply of foods, but it includes even the accessibility of prices and their nutritional and qualitative adequacy. In this context many countries recognize the importance of trade policies to ensure adequate levels of food security. The aim of this work was to analyze the impact of trade openness on the level of food security in European countries, using a dynamic panel analysis with the generalized method of moments (GMM) approach. We selected two different indicators of food security (average protein supply, average dietary energy supply adequacy) capable of offering information both on the quantity and on the nutritional quality of the food supply. In order to improve the robustness of the empirical results, we developed three different regressions, with three trade openness indicators (trade openness, tariff, globalization) for each food security indicator. The results showed that commercial opening has, on average, a statistically significant net positive impact on the food security of European countries. Additional results indicate that also economic development, together with the importance of the agricultural sector, can improve food security levels.


Asunto(s)
Desarrollo Económico , Abastecimiento de Alimentos , Agricultura , Europa (Continente) , Internacionalidad
10.
EMBO Rep ; 20(10): e47788, 2019 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-31418171

RESUMEN

Extracellular HMGB1 triggers inflammation following infection or injury and supports tumorigenesis in inflammation-related malignancies. HMGB1 has several redox states: reduced HMGB1 recruits inflammatory cells to injured tissues forming a heterocomplex with CXCL12 and signaling via its receptor CXCR4; disulfide-containing HMGB1 binds to TLR4 and promotes inflammatory responses. Here we show that diflunisal, an aspirin-like nonsteroidal anti-inflammatory drug (NSAID) that has been in clinical use for decades, specifically inhibits in vitro and in vivo the chemotactic activity of HMGB1 at nanomolar concentrations, at least in part by binding directly to both HMGB1 and CXCL12 and disrupting their heterocomplex. Importantly, diflunisal does not inhibit TLR4-dependent responses. Our findings clarify the mode of action of diflunisal and open the way to the rational design of functionally specific anti-inflammatory drugs.


Asunto(s)
Quimiocina CXCL12/metabolismo , Diflunisal/farmacología , Proteína HMGB1/metabolismo , Leucocitos/metabolismo , Células 3T3 , Animales , Quimiotaxis/efectos de los fármacos , Diflunisal/química , Disulfuros/metabolismo , Ácido Glicirrínico/farmacología , Humanos , Inflamación/patología , Leucocitos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Ratones
11.
Sci Total Environ ; 645: 1425-1431, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30248864

RESUMEN

In this paper, we present a new approach based on the Grey Water Footprint (GWF) concept for the determination of groundwater nitrate contamination, with a focus on the agricultural impact in the Southern Apulia Region (Italy). The GWF assessment allows us to highlight wells where nitrate contamination is higher and for which a verification of the nature of contamination is necessary, potentially identifying certain contexts associated with risk factors present in the area. Data show higher nitrate GWF values for vineyards than for olive groves, particularly in areas used for the production of table grapes. Indeed, it is possible to observe that the Western Ionian-Tarantino arch is characterized by a high average level of the GWF indicator, area characterized by an agricultural land use (vineyards, orchards, simple arable land). Another important area is the Brindisi plain, predominantly characterized by an agricultural vocation and a related fertilizer use. The situation in the whole Salento peninsula is more heterogeneous. The results of the GWF show high values in equally distributed points with a clear frequency in the coastal areas of the Ionic arch (Eastern Tarantino and Salento). The Water Footprint methodology and in particular the GWF approach used in this study conceives a useful indicator for the agricultural policy planning processes, a criterion to establish land use management according to the status of hydrological basin and a tool for assessing the pollution monitoring programs.

12.
Langmuir ; 33(30): 7512-7528, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28683199

RESUMEN

Extracellular matrix (ECM)-mimicking surfaces are pivotal tools in understanding adherent cell physiopathology. In this sense, we have recently reported on a discrete set of ECM-mimicking SAMs, among which only those exposing IGDQ peptide-alkanethiols sustain the adhesion of MDA-MB-231 cells by triggering FAK phosphorylation and peculiarly induce the migration of individual cancer cells on the subcentimeter scale. Starting from the experimentally observed relationship among the SAM composition, organization, and biological response, a systematic computational characterization aided in pinpointing the atomistic details through which specific composition and organization achieve the desired biological responsiveness. Specifically, the solvent, number and type of peptides, and presence or absence of surface fillers were accurately considered, creating representative model SAMs simulated by means of classical molecular dynamics (MD) with a view toward unravelling the experimental evidence, revealing how the conformational and structural features of these substrates dictate the specific motogenic responses. Through complementary experimental and computational investigations, it clearly emerges that there exists a distinct and precise mutual interaction among IGDQ-peptides, the surface fillers, and Au, which controls the structural properties of the ECM-mimicking SAMs and thus their motogenic potential.


Asunto(s)
Péptidos/química , Matriz Extracelular , Conformación Molecular , Simulación de Dinámica Molecular , Fosforilación
13.
Sci Total Environ ; 599-600: 474-482, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28482305

RESUMEN

At global scale, the majority of world water withdrawal is for the agricultural sector, with differences among countries depending on the relevance of agri-food sector in the economy. Virtual water and water footprint could be useful to express the impact on the water resources of each production process and good with the objective to lead to a sustainable use of water at a global level. International trade could be connected to the virtual water flows, in fact through commodities importation, water poor countries can save their own water resources. The present paper focuses on the bilateral virtual water flows connected to the top ten agri-food products traded between Italy and China. Comparing the virtual water flow related to the top 10 agri-food products, the virtual water flow from Italy to China is bigger than the water flow in the opposite direction. Moreover, the composition of virtual water flows is different; Italy imports significant amounts of grey water from China, depending on the different environmental strategies adopted by the two selected countries. This difference could be also related to the fact that traded commodities are very different; the 91% of virtual water imported by Italy is connected to crops products, while the 95% of virtual water imported by China is related to the animal products. Considering national water saving and global water saving, appears that Italy imports virtual water from China while China exerts pressure on its water resources to supply the exports to Italy. This result at global scale implies a global water loss of 129.29millionm3 because, in general, the agri-food products are traded from the area with lower water productivity to the area with the higher water productivity.

14.
J Am Chem Soc ; 139(7): 2710-2727, 2017 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-28051311

RESUMEN

Because of the peculiar dynamic covalent reactivity of boronic acids to form tetraboronate derivatives, interest in using their aryl derivatives in materials science and supramolecular chemistry has risen. Nevertheless, their ability to form H-bonded complexes has been only marginally touched. Herein we report the first solution and solid-state binding studies of the first double-H-bonded DD·AA-type complexes of a series of aromatic boronic acids that adopt a syn-syn conformation with suitable complementary H-bonding acceptor partners. The first determination of the association constant (Ka) of ortho-substituted boronic acids in solution showed that Ka for 1:1 association is in the range between 300 and 6900 M-1. Crystallization of dimeric 1:1 and trimeric 1:2 and 2:1 complexes enabled an in-depth examination of these complexes in the solid state, proving the selection of the -B(OH)2 syn-syn conformer through a pair of frontal H-bonds with the relevant AA partner. Non-ortho-substituted boronic acids result in "flat" complexes. On the other hand, sterically demanding analogues bearing ortho substituents strive to retain their recognition properties by rotation of the ArB(OH)2 moiety, forming "T-shaped" complexes. Solid-state studies of a diboronic acid and a tetraazanaphthacene provided for the first time the formation of a supramolecular H-bonded polymeric ribbon. On the basis of the conformational dynamicity of the -B(OH)2 functional group, it is expected that these findings will also open new possibilities in metal-free catalysis or organic crystal engineering, where double-H-bonding donor boronic acids could act as suitable organocatalysts or templates for the development of functional materials with tailored organizational properties.

15.
Chemistry ; 23(10): 2363-2378, 2017 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-27897357

RESUMEN

The synthesis of O-doped polyaromatic hydro- carbons in which two polycyclic aromatic hydrocarbon sub units are bridged through one or two O atoms has been achieved. This includes high-yield ring-closure key steps that, depending on the reaction conditions, result in the formation of furanyl or pyranopyranyl linkages through intramolecular C-O bond formation. Comprehensive photophysical measurements in solution showed that these compounds have exceptionally high emission yields and tunable absorption properties throughout the UV/Vis spectral region. Electrochemical investigations showed that in all cases O annulation increases the electron-donor capabilities by raising the HOMO energy level, whereas the LUMO energy level is less affected. Moreover, third-order nonlinear optical (NLO) measurements on solutions or thin films containing the dyes showed very good values of the second hyperpolarizability. Importantly, poly(methyl methacrylate) films containing the pyranopyranyl derivatives exhibited weak linear absorption and NLO absorption compared to the nonlinearity and NLO refraction, respectively, and thus revealed them to be exceptional organic materials for photonic devices.

16.
Pharmacol Res ; 111: 534-544, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27378565

RESUMEN

High Mobility Group Box 1 protein was discovered as a nuclear protein, but it has a "second life" outside the cell where it acts as a damage-associated molecular pattern. HMGB1 is passively released or actively secreted in a number of diseases, including trauma, chronic inflammatory disorders, autoimmune diseases and cancer. Extracellular HMGB1 triggers and sustains the inflammatory response by inducing cytokine release and by recruiting leucocytes. These characteristics make extracellular HMGB1 a key molecular target in multiple diseases. A number of strategies have been used to prevent HMGB1 release or to inhibit its activities. Current pharmacological strategies include antibodies, peptides, decoy receptors and small molecules. Noteworthy, salicylic acid, a metabolite of aspirin, has been recently found to inhibit HMGB1. HMGB1 undergoes extensive post-translational modifications, in particular acetylation and oxidation, which modulate its functions. Notably, high levels of serum HMGB1, in particular of the hyper-acetylated and disulfide isoforms, are sensitive disease biomarkers and are associated with different disease stages. In the future, the development of isoform-specific HMGB1 inhibitors may potentiate and fine-tune the pharmacological control of inflammation. We review here the current therapeutic strategies targeting HMGB1, in particular the emerging and relatively unexplored small molecules-based approach.


Asunto(s)
Proteína HMGB1 , Animales , Productos Biológicos/farmacología , Biomarcadores/metabolismo , Proteína HMGB1/antagonistas & inhibidores , Proteína HMGB1/metabolismo , Humanos , Terapia Molecular Dirigida
17.
Small ; 12(3): 321-9, 2016 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-26583377

RESUMEN

Thiolated peptides bearing the Ile-Gly-Asp (IGD) motif, a highly conserved sequence of fibronectin, are used for the preparation of anisotropic self-assembled monolayers (SAM gradients) to study the whole-population migratory behavior of metastatic breast cancer cells (MDA-MB-231 cells). Ile-Gly-Asp-Gln-(IGDQ)-exposing SAMs sustain the adhesion of MDA-MB-231 cells by triggering focal adhesion kinase phosphorylation, similarly to the analogous Gly-Arg-Gly-Asp-(GRGD)-terminating surfaces. However, the biological responses of different cell lines interfaced with the SAM gradients show that only those exposing the IGDQ sequence induce significant migration of MDA-MB-231 cells. In particular, the observed migratory behavior suggests the presence of cell subpopulations associated with a "stationary" or a "migratory" phenotype, the latter determining a considerable cell migration at the sub-cm length scale. These findings are of great importance as they suggest for the first time an active role of biological surfaces exposing the IGD motif in the multicomponent orchestration of cellular signaling involved in the metastatic progression.


Asunto(s)
Neoplasias/patología , Péptidos/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Oro/química , Humanos , Microscopía Confocal , Péptidos/química , Propiedades de Superficie , Agua/química
18.
Angew Chem Int Ed Engl ; 54(52): 15739-43, 2015 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-26637106

RESUMEN

Through the simultaneous use of three orthogonal dynamic covalent reactions, namely disulfide, boronate, and acyl hydrazone formation, we conceived a facile and versatile protocol to spatially organize tailored chromophores, which absorb in the blue, red, and yellow regions, on a preprogrammed α-helix peptide. This approach allowed the assembly of the dyes in the desired ratio and spacing, as dictated by both the relative positioning and distribution of the recognition units on the peptide scaffold. Steady-state UV/Vis absorption and emission studies suggest an energy transfer from the yellow and red donors to the blue acceptor. A molecular dynamics simulation supports the experimental findings that the helical structure is maintained after the assembly and the three dyes are confined in defined conformational spaces.

19.
Chemistry ; 21(43): 15377-87, 2015 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-26471446

RESUMEN

The synthesis, X-ray crystal structures, ground- and excited-state UV/Vis absorption spectra, and luminescence properties of chalcogen-doped organic emitters equipped on both extremities with benzoxa-, benzothia-, benzoselena- and benzotellurazole (1X and 2X ) moieties have been reported for the first time. The insertion of the four different chalcogen atoms within the same molecular skeleton enables the investigation of only the chalcogenic effect on the organisation and photophysical properties of the material. Detailed crystal-structure analyses provide evidence of similar packing for 2O -2Se , in which the benzoazoles are engaged in π-π stacking and, for the heavier atoms, in secondary X⋅⋅⋅X and X⋅⋅⋅N bonding interactions. Detailed computational analysis shows that the arrangement is essentially governed by the interplay of van der Waals and secondary bonding interactions. Progressive quenching of the fluorescence and concomitant onset of phosphorescence features with gradually shorter lifetimes are detected as the atomic weight of the chalcogen heteroatom increases, with the tellurium-doped derivatives exhibiting only emission from the lowest triplet excited state. Notably, the phosphorescence spectra of the selenium and tellurium derivatives can be recorded even at room temperature; this is a very rare finding for fully organic emitters.

20.
Chem Soc Rev ; 44(19): 6916-53, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-26139348

RESUMEN

This critical review aims at giving insights on the spontaneous tendency of proteins and their constitutive parts to adsorb on graphitic nanomaterials (GNMs) through non-covalent interactions occurring at their interfaces. Specifically, it focuses on the theoretical and experimental studies carried out to comprehend in depth the forces ruling the adsorption processes of proteins on fullerene, carbon nanotubes and graphene. In a systematic way the reader is guided through the most recent and representative examples describing at the atomistic level of detail the structural modalities and the chemico-physical principles through which amino acids, polypeptides and folded proteins interact with GNMs' surface, thereby taking into consideration the mutual effects of both protein structural complexity and nanomaterial topology. Based on their chemical and structural features, the study and understanding of the protein-nanomaterial interfaces can be exploited in the view of design and control the spontaneous formation of biologically-active hybrid materials for the development of new tailored applications in the field of sensing, nanomedicine and biochemistry.


Asunto(s)
Fulerenos/química , Grafito/química , Nanoestructuras/química , Nanotecnología/métodos , Proteínas/química , Adsorción , Aminoácidos/química , Microscopía de Fuerza Atómica , Simulación del Acoplamiento Molecular , Nanotubos de Carbono/química , Péptidos/química
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