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1.
Chem Sci ; 10(9): 2708-2717, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30996988

RESUMO

Chiral oligothiophene monomers with C 2 symmetry, based on 3,3'-bithiophene atropisomeric cores with high racemization barriers, have recently been shown to provide excellent chiral starting materials with high electroactivity for the easy preparation of enantiopure electroactive films endowed with powerful chirality manifestations. We now introduce an inherently chiral monomer based on a 2,2'-biindole core, as the prototype of a new inherently chiral monomer family, whose properties could be modulable through functionalization of the pyrrolic N atoms. By fast, regular electrooligomerization the new monomer yields inherently chiral films with high, reversible electroactivity and, above all, impressive enantioselectivity towards very different chiral probes, some of pharmaceutical interest, as general-scope electrode surfaces. Such results, while opening the way to a new, attractive inherently chiral selector class, nicely confirm the general validity of the inherent chirality strategy for chiral electrochemistry. Furthermore, the enantioselectivity of the new selectors not only holds with electroactive chiral probes, but also with circularly polarized light components as well as electron spins, resulting in good chiroptical and spin filter performances, which suggests fascinating correlations between the three contexts.

2.
Molecules ; 24(3)2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30736414

RESUMO

Gelatin is a biopolymer with interesting properties that can be useful for biomaterial design for different applications such as drug delivery systems, or 3D scaffolds for tissue engineering. However, gelatin suffers from poor mechanical stability at physiological temperature, hence methods for improving its properties are highly desirable. In the present work, a new chemical cross-linking strategy based on triazolinedione ene-type chemistry towards stable hydrogel is proposed. Two different homobifunctional 1,2,4-triazoline-3,5(4H)-diones, namely 4,4'-hexane-1,6-diylbis(3H-1,2,4-triazoline-3,5(4H)-dione) 1 and 4,4'-[methylenebis(4,1-phenylene)]bis(3H-1,2,4-triazoline-3,5(4H)-dione) 2 were used as cross-linkers in different ratio to tyrosine residues in gelatin. The reaction was proved effective in all experimented conditions and hydrogels featured with different thermal stability were obtained. In general, the higher the cross-linker/tyrosine ratio, the more thermostable the hydrogel. The swelling properties are strictly dependent upon the chemical nature of the cross-linker.


Assuntos
Gelatina/química , Hidrogéis/química , Triazóis/química , Tirosina/química , Materiais Biocompatíveis/química , Estabilidade de Medicamentos , Teste de Materiais , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
3.
Phys Chem Chem Phys ; 20(41): 26161-26172, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30311617

RESUMO

The structure and electronic properties of carbon-based nanostructures obtained by metal surface assisted synthesis is highly dependent on the nature of the precursor molecule. Here, we report on a combined scanning tunneling microscopy, soft X-ray spectroscopy and density functional theory investigation on the surface assisted polymerization of Br-corannulene at Ag(110) and on the possibility of building a mesh of π-conjugated polymers starting from buckyball shaped molecules. Indeed, the corannulene units form one-molecule-wide ribbons in which the natural concavity of the precursor molecule is maintained. These C-based nanostructures are corrugated and merge into a covalent network on the surface.

4.
Stroke ; 48(12): 3316-3322, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29101258

RESUMO

BACKGROUND AND PURPOSE: Public campaigns to increase stroke preparedness have been tested in different contexts, showing contradictory results. We evaluated the effectiveness of a stroke campaign, designed specifically for the Italian population in reducing prehospital delay. METHODS: According to an SW-RCT (Stepped-Wedge Cluster Randomized Controlled Trial) design, the campaign was launched in 4 provinces in the northern part of the region Emilia Romagna at 3-month intervals in randomized sequence. The units of analysis were the patients admitted to hospital, with stroke and transient ischemic attack, over a time period of 15 months, beginning 3 months before the intervention was launched in the first province to allow for baseline data collection. The proportion of early arrivals (within 2 hours of symptom onset) was the primary outcome. Thrombolysis rate and some behavioral end points were the secondary outcomes. Data were analyzed using a fixed-effect model, adjusting for cluster and time trends. RESULTS: We enrolled 1622 patients, 912 exposed and 710 nonexposed to the campaign. The proportion of early access was nonsignificantly lower in exposed patients (354 [38.8%] versus 315 [44.4%]; adjusted odds ratio, 0.81; 95% confidence interval, 0.60-1.08; P=0.15). As for secondary end points, an increase was found for stroke recognition, which approximated but did not reach statistical significance (P=0.07). CONCLUSIONS: Our campaign was not effective in reducing prehospital delay. Even if some limitations of the intervention, mainly in terms of duration, are taken into account, our study demonstrates that new communication strategies should be tested before large-scale implementation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01881152.


Assuntos
Educação em Saúde/estatística & dados numéricos , Acidente Vascular Cerebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Determinação de Ponto Final , Feminino , Humanos , Ataque Isquêmico Transitório/terapia , Itália , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Estudos Prospectivos , Fatores de Risco , Terapia Trombolítica/estatística & dados numéricos , Tempo para o Tratamento , Resultado do Tratamento , Adulto Jovem
5.
Nanoscale ; 8(41): 17843-17853, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27714142

RESUMO

By a combination of scanning tunneling microscopy, X-ray spectroscopic techniques and density functional theory calculations, we prove the formation of extended patterns of parallel, graphene nanoribbons with alternate zig-zag and armchair edges and selected width by surface-assisted Ullmann coupling polymerization and dehydrogenation of 1,6-dibromopyrene (C16H8Br2). Besides the relevance of these nanostructures for their possible application in nanodevices, we demonstrate the peculiarity of halogenated pyrene derivatives for the formation of nanoribbons, in particular on Ag(110). These results open the possibility of tuning the shape and dimension of nanoribbons (and hence the correlated electronic properties) by choosing suitably tailored or on-purpose designed molecular precursors.

6.
Ultrason Sonochem ; 27: 30-36, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26186817

RESUMO

An ultrasound-assisted three-component, one-pot domino reaction with ferrocenecarboxaldehyde is herein reported. The sequence of reactions entails the allylindation and dehydrative alkylation of stabilized C-nucleophiles (e.g. electron-rich-(hetero)aromatics and stabilized enols) and N-nucleophiles (e.g. azoles). Sonochemical reactions have been performed in three different high-intensity reactors: a bath (20.3 kHz, 60 W), as well as two cup horns working at 19.9 kHz (75 W) and 300.5 kHz (70 W) giving a library of 18 new ferrocenyl derivatives.

7.
Chem Commun (Camb) ; 51(63): 12593-6, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26154619

RESUMO

The surface-assisted synthesis of gold-organometallic hybrids on the Au(111) surface both by thermo- and light-initiated dehalogenation of bromo-substituted tetracene is reported. Combined X-ray photoemission (XPS) and scanning tunneling microscopy (STM) data reveal a significant increase of the surface order when mild reaction conditions are combined with 405 nm light irradiation.

8.
Molecules ; 18(11): 13705-22, 2013 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-24201207

RESUMO

A library of new heterocyclic systems was synthesized starting from oxcarbazepine (OXC, Trileptal, 10-oxo-10,11-dihydro-5H-dibenzo[b,f]azepine-5-carboxamide). The key for these transformations is the α-enolizable ketone present on the [d]-side of our starting material OXC, thus, an in depth investigation of the literature to find heteroannulation reactions for substrates carrying an α-enolizable ketone gave us a boost to discover an excellent derivatization strategy and [3+2], [4+2] and [4+1] approaches were successfully developed. Almost always a pre-functionalization was needed, but also the direct one-pot heterocycle construction was also explored.


Assuntos
Carbamazepina/análogos & derivados , Carbamazepina/química , Compostos Heterocíclicos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oxcarbazepina
9.
J Neurol Sci ; 217(2): 181-8, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14706222

RESUMO

The purpose of this study was to provide further insight into the effective relevance of the association between Chlamydia pneumoniae and MS. We evaluated by ELISA technique cerebrospinal fluid (CSF) and serum levels of anti-C. pneumoniae IgG in 46 relapsing-remitting (RR), 14 secondary progressive (SP) and 11 primary progressive (PP) MS patients grouped according to clinical and Magnetic Resonance Imaging (MRI) evidence of disease activity. Fifty-one patients with other inflammatory neurological disorders (OIND) and 52 with non-inflammatory neurological disorders (NIND) were used as controls. A C. pneumoniae-specific intrathecal IgG synthesis as detected by the relative specific index was present in a small proportion of MS (17%), OIND (22%) and NIND (2%) patients and was significantly more frequent in MS and in OIND than in NIND (p<0.001) and in SP and PP MS than in RR MS patients (p<0.02). Among the patients with C. pneumoniae-specific intratecally produced antibodies, CSF high-affinity anti-C. pneumoniae IgG were found in the majority of SP or PP MS, occasionally in OIND, but not in RR MS and NIND patients. These findings confirm that the presence of a humoral immune response to C. pneumoniae within the central nervous system (CNS) is not selectively restricted to MS, but is shared by several inflammatory neurological conditions. In addition, our results suggest that an intrathecal production of C. pneumoniae-specific high-affinity IgG can occur in a subset of patients with MS progressive forms in which a C. pneumoniae brain chronic persistent infection may play an important pathogenetic role.


Assuntos
Infecções por Chlamydia/líquido cefalorraquidiano , Infecções por Chlamydia/complicações , Chlamydophila pneumoniae/patogenicidade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/microbiologia , Adulto , Formação de Anticorpos/imunologia , Encéfalo/diagnóstico por imagem , Encéfalo/imunologia , Encéfalo/microbiologia , Infecções por Chlamydia/imunologia , Chlamydophila pneumoniae/imunologia , Encefalite/líquido cefalorraquidiano , Encefalite/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Radiografia
10.
J Neuroimmunol ; 142(1-2): 149-58, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14512174

RESUMO

We have investigated the presence of non-classical soluble HLA-G molecules (sHLA-G) in cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients and the possible relationships between CSF levels of sHLA-G, classical soluble HLA-I (sHLA-I) molecules, IL-10 amounts and Magnetic Resonance Imaging (MRI) findings were evaluated. We studied by ELISA technique the sHLA-I, sHLA-G and IL-10 levels in CSF of 50 relapsing-remitting (RR) MS patients stratified according to clinical and MRI evidence of disease activity. Thirty-six patients with other inflammatory neurological disorders (OIND) and 41 with non-inflammatory neurological disorders (NIND) were used as controls. CSF mean levels were significantly higher in MS and OIND than in NIND for sHLA-I (p<0.001) and in MS than in controls for sHLA-G (p<0.001), with no differences among the various groups for IL-10 mean concentrations. An increase in CSF sHLA-I was found in MS patients with Gd-enhancing lesions (p<0.01), while sHLA-G and IL-10 were more represented in MS patients without lesional activity on MRI scans (p<0.02). In MRI-inactive MS, CSF IL-10 mean concentrations were significantly greater in patients with CSF-detectable levels of sHLA-G than in those without any evidence of CSF sHLA-G expression (p<0.05). Our findings suggest that CSF classical sHLA-I and non-classical sHLA-G levels may modulate MS activity as assessed by MRI acting in opposite directions. The association observed between sHLA-G and IL-10 when Gd-enhancing lesion resolved indicates a potential immunoregulatory role for IL-10 in the control of MS disease activity by shifting the sHLA-I/sHLA-G balance towards sHLA-G response.


Assuntos
Antígenos HLA/líquido cefalorraquidiano , Antígenos de Histocompatibilidade Classe I/líquido cefalorraquidiano , Interleucina-10/líquido cefalorraquidiano , Imagem por Ressonância Magnética , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Esclerose Múltipla Recidivante-Remitente/imunologia , Adulto , Anticorpos Monoclonais , Western Blotting , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Feminino , Gadolínio , Antígenos HLA/imunologia , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Inflamação/líquido cefalorraquidiano , Inflamação/diagnóstico , Inflamação/imunologia , Imagem por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Doenças do Sistema Nervoso/líquido cefalorraquidiano , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/imunologia , Solubilidade
11.
J Neuroimmunol ; 133(1-2): 151-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12446018

RESUMO

The goal of our study was to clarify the contribution of soluble human leukocyte antigens class I (sHLA-I) in multiple sclerosis (MS) immune dysregulation. We retrospectively evaluated by ELISA cerebrospinal fluid (CSF) and serum sHLA-I levels in 79 relapsing-remitting (RR), 26 secondary progressive (SP) and 15 primary progressive (PP) MS patients stratified according to clinical and Magnetic Resonance Imaging (MRI) evidence of disease activity. One hundred and nine patients with other inflammatory neurological disorders (OIND), 88 with noninflammatory neurological disorders (NIND) and 82 healthy donors were used as controls. An intrathecal synthesis of sHLA-I detected by a specific index was significantly more consistent in MS than in controls, with more pronounced values in MS patients with relapses and MRI enhancing brain lesions. A decrease in serum sHLA-I concentrations was observed in MS patients with demyelinating attacks, while an increase in CSF levels of sHLA-I was found in MS patients with lesional activity on MRI scans. This association between intrathecal synthesis and reciprocal fluctuations of CSF and serum levels of sHLA-I in clinically and MRI active MS seems to suggest a potential role for CSF and serum levels of sHLA-I as a sensitive marker of immune activation taking place both intrathecally and systemically in MS.


Assuntos
Sistema Nervoso Central/imunologia , Antígenos de Histocompatibilidade Classe I/sangue , Antígenos de Histocompatibilidade Classe I/líquido cefalorraquidiano , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Adulto , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Progressão da Doença , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Valor Preditivo dos Testes , Estudos Retrospectivos
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