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1.
Appl Physiol Nutr Metab ; 45(12): 1345-1352, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32574506

RESUMO

Neuroplasticity and recovery after stroke can be enhanced by a rehabilitation program pertinent to upper limb motor function exercise and mental imagery (EMI) as well as hyperbaric oxygen therapy (HBOT). We assessed feasibility and safety of the combined approach utilizing both HBOT and EMI, and to derive preliminary estimates of its efficacy. In this randomized controlled trial, 27 patients with upper extremity hemiparesis at 3-48 months after stroke were randomized to receive either a complementary rehabilitation program of HBOT-EMI (intervention group), or EMI alone (control group). Feasibility and safety were assessed as total session attendance, duration of sessions, attrition rates, missing data, and intervention-related adverse events. Secondary clinical outcomes were assessed with both objective tools and self-reported measures at baseline, 8 weeks (end of treatment), and 12-weeks follow-up. Session attendance, duration, and attrition rate did not differ between the groups; there were no serious adverse events. Compared with baseline, there were significant sustained improvements of objective and subjective outcomes' measures in the intervention group, and a single improvement in an objective measure in the control group. Between-group outcome comparisons were not statistically significant. This study demonstrated that the combination HBOT-EMI was a safe and feasible approach in patients recovering from chronic stroke. There were also trends for improved motor function of the affected upper limb after the treatments. ClinicalTrials.gov registration no.: NCT02666469. Novelty HBOT combined with an upper limb exercise and mental imagery rehabilitation program is feasible and safe in chronic stroke patients. This combined approach showed trends for improved functional recovery.


Assuntos
Terapia por Exercício , Oxigenoterapia Hiperbárica , Imaginação , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral , Extremidade Superior/fisiologia , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego
2.
Sci Total Environ ; 577: 45-53, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27751687

RESUMO

In the last years, applications for silver nanoparticles (Ag NPs) continue to increase together with the concerns about their potential input and hazards in aquatic ecosystems, where microalgae are key organisms. The aim of the present study was to assess the relative sensitivity of three marine microalgae species with differences in cell wall composition/structure exposed to Poly N-vinyl-2-pirrolidone/Polyethyleneimine (PVP/PEI) coated 5nm Ag NPs and uncoated 47nm Ag NP. As limited attention has been paid to the role of coating agents in NP toxicity, the effect of PVP/PEI alone was also evaluated. After 72h in artificial seawater, 47nm Ag NPs formed around 1400nm size aggregates while PVP/PEI coated 5nm Ag NPs reached around 90nm. Ag+ release in seawater was around 3% for 47nm Ag NPs and 30% for PVP/PEI coated 5nm Ag NPs. PVP/PEI coated 5nm Ag NP aggregates entrapped the algal cells in a network of heteroaggregates, while uncoated 47nm Ag NPs interacted to a lesser extent with algae. The concentration of PVP/PEI coated 5nm Ag NPs that exerted the median effect (EC50) on algae growth pointed out differences in algae sensitivity: T. suecica was about 10 times more sensitive than I. galbana and P. tricornutum. Further, the coating agent alone was as toxic to algae as PVP/PEI coated 5nm Ag NPs, suggesting that presence of the coating agent was the main driver of toxicity of coated NPs. Uncoated 47nm Ag NPs instead, showed similar toxicity towards algae although P. tricornutum was slightly less sensitive than T. suecica and I. galbana, which agrees with the presence of a resistant silicified cell wall in the diatom. The present work demonstrates differences in sensitivity of three marine microalgae, possibly related to their cell surface and size characteristics.


Assuntos
Nanopartículas Metálicas/química , Microalgas/efeitos dos fármacos , Prata/farmacologia , Diatomáceas , Polietilenoimina , Pirrolidinonas , Água do Mar
3.
Sci Total Environ ; 550: 619-627, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26849326

RESUMO

The increasing use of oxide nanoparticles (NPs) in commercial products has intensified the potential release into the aquatic environment where algae represent the basis of the trophic chain. NP effects upon algae population growth were indeed already reported in literature, but the concurrent effects at cellular and genomic levels are still largely unexplored. Our work investigates the genotoxic (by COMET assay) and cytotoxic effects (by qualitative ROS production and cell viability) of ZnO nanoparticles toward marine microalgae Dunaliella tertiolecta. A comparison at defined population growth inhibition levels (i.e. 50% Effect Concentration, EC50, and No Observed Effect Concentration, NOEC) with SiO2 and TiO2 genotoxic effects and previously investigated cytotoxic effects (Manzo et al., 2015) was performed in order to elucidate the possible diverse mechanisms leading to algae growth inhibition. After 72h exposure, ZnO particles act firstly at the level of cell division inhibition (EC50: 2mg Zn/L) while the genotoxic action is evident only starting from 5mg Zn/L. This outcome could be ascribable mainly to the release of toxic ions from the aggregate of ZnO particle in the proximity of cell membrane. In the main, at EC50 and NOEC values for ZnO NPs showed the lowest cytotoxic and genotoxic effect with respect to TiO2 and SiO2. Based on Mutagenic Index (MI) the rank of toxicity is actually: TiO2>SiO2>ZnO with TiO2 and SiO2 that showed similar MI values at both NOEC and EC50 concentrations. The results presented herein suggest that up to TiO2 NOEC (7.5mg/L), the algae DNA repair mechanism is efficient and the DNA damage does not result in an evident algae population growth inhibition. A similar trend for SiO2, although at lower effect level with respect to TiO2, is observable. The comparison among all the tested nanomaterial toxicity patterns highlighted that the algae population growth inhibition occurred through pathways specific for each NP also related to their different physicochemical behaviors in seawater.


Assuntos
Clorófitas/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Dióxido de Silício/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Clorófitas/crescimento & desenvolvimento , Ensaio Cometa , Mutagênicos
4.
Environ Sci Pollut Res Int ; 22(20): 15941-51, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26054456

RESUMO

Nanoparticles (NPs) are widely used in many industrial applications. NP fate and behavior in seawater are a very important issue for the assessment of their environmental impact and potential toxicity. In this study, the toxic effects of two nanomaterials, silicon dioxide (SiO2) and titanium dioxide (TiO2) NPs with similar primary size (~20 nm), on marine microalgae Dunaliella tertiolecta were investigated and compared. The dispersion behavior of SiO2 and TiO2 NPs in seawater matrix was investigated together with the relative trend of the exposed algal population growth. SiO2 aggregates rapidly reached a constant size (600 nm) irrespective of the concentration while TiO2 NP aggregates grew up to 4 ± 5 µm. The dose-response curve and population growth rate alteration of marine alga D. tertiolecta were evaluated showing that the algal population was clearly affected by the presence of TiO2 NPs. These particles showed effects on 50 % of the population at 24.10 [19.38-25.43] mg L(-1) (EC50) and a no observed effect concentration (NOEC) at 7.5 mg L(-1). The 1 % effect concentration (EC1) value was nearly above the actual estimated environmental concentration in the aquatic environment. SiO2 NPs were less toxic than TiO2 for D. tertiolecta, with EC50 and NOEC values one order of magnitude higher. The overall toxic action seemed due to the contact between aggregates and cell surfaces, but while for SiO2 a direct action upon membrane integrity could be observed after the third day of exposure, TiO2 seemed to exert its toxic action in the first hours of exposure, mostly via cell entrapment and agglomeration.


Assuntos
Microalgas/efeitos dos fármacos , Nanopartículas/toxicidade , Dióxido de Silício/química , Dióxido de Silício/toxicidade , Titânio/química , Titânio/toxicidade , Volvocida/efeitos dos fármacos , Clorófitas/efeitos dos fármacos , Ecotoxicologia , Água do Mar/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-21096551

RESUMO

The development of new transition metal complexes (TMCs) sensing materials, based on di-rhodium (II,II) complexes with a lantern structure, is investigated. Specifically, in this work is reported a study carried out with the Rh2(form)4 complex having the formamidinate (form = N.N-p-tolylformamidinate anion) bridging ligand in the equatorial positions. Thick films of the complex have been deposited on interdigitated alumina substrate and their electrical characteristics have been evaluated. Rh2(form)4 behaves as a p-type semiconductor, showing a large decrease in forward and reverse current in presence of ammonia vapors in air. The preliminary results reported promise a practical application of the developed devices in the breath analysis for clinical diagnostics.


Assuntos
Amônia/análise , Amônia/química , Materiais Biocompatíveis/química , Técnicas Biossensoriais/instrumentação , Testes Respiratórios/instrumentação , Condutometria/instrumentação , Ródio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Semicondutores
6.
J Endocrinol Invest ; 32(10): 832-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19605975

RESUMO

BACKGROUND/AIMS: While Angiotensin II (Ang II) is a major factor in the development of cardiomyocyte hypertrophy and a pivotal role for Ang II signals via ERK1/2 has been identified, mechanism(s) responsible are still unclear. As Bartter's and Gitelman's syndrome patients (BS/GS) have increased Ang II, and yet normo/hypotension, hyporesponsiveness to pressors and blunted Ang II signaling via type 1 receptors (AT1R), this study assesses BS/GS's left ventricular (LV) mass and structure as well as Ang II induced ERK1/2 phosphorylation compared with essential hypertensive patients (EH) and normotensive healthy subjects (C) to gain insight into Ang II mediated processes. METHODS: Indices of cardiac hypertrophy were determined by M-mode, two-dimensional echo Doppler and ERK phosphorylation by Western blot. RESULTS: None of BS/GS exhibited LV remodelling; LV mass, LV end-diastolic volume and mass/volume ratio were unchanged vs C (60+/-14 g/m2 vs 64+/-12, 64+/-12 ml/m2 vs 60+/-8 and 0.95+/-0.2 vs 1.0+/-0.2, respectively) and reduced vs EH (119+/-15, p<0.001, 78+/-9, p<0.05 and 1.52+/-0.15, p<0.01). Despite BS/GS's higher plasma renin activity and aldosterone and unchanged level of AT1R, Ang II induced ERK1/2 phosphorylation was reduced vs both C and EH: 0.64 d.u.+/-0.08 vs 0.90+/-0.06 in C, p<0.006, and vs 1.45+/-0.07 in EH, p<0.001. CONCLUSION: The data point to a direct cardioremodeling role for Ang II and support a role of Ang II type 2 receptor (AT2R) signaling as involved in the lack of cardiovascular remodeling in BS/GS. However, further studies using more direct approaches to demonstrate the effects of AT2R signaling must be pursued.


Assuntos
Síndrome de Bartter/fisiopatologia , Síndrome de Gitelman/fisiopatologia , Receptor Tipo 2 de Angiotensina/metabolismo , Adolescente , Adulto , Aldosterona/sangue , Análise de Variância , Angiotensina II/farmacologia , Síndrome de Bartter/diagnóstico por imagem , Síndrome de Bartter/metabolismo , Western Blotting , Células Cultivadas , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Síndrome de Gitelman/diagnóstico por imagem , Síndrome de Gitelman/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Tamanho do Órgão , Fosforilação/efeitos dos fármacos , Renina/sangue , Transdução de Sinais/efeitos dos fármacos , Ultrassonografia
8.
Ann Chim ; 91(1-2): 51-63, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11329769

RESUMO

In this paper we report on the results regarding the hydric properties of lithic materials widely used in north-eastern Sicily. We report also on the hydrophobic properties of these stones treated with some preserving products (silanes, siloxanes, epoxides, perfluoropolyethers, acrylates, acrylsilicones). In addition, the quantitative colour readings of the untreated and treated stones are presented, together with their chromatic alterations after artificial UV weathering. Final considerations on the selection of the best regime treatment are also reported.


Assuntos
Minerais/química , Escultura , Acrilatos/química , Adsorção , Carbonato de Cálcio/química , Cor , Materiais de Construção , Poluição Ambiental , Compostos de Epóxi/química , Éteres/química , Fluorocarbonos/química , Teste de Materiais , Sicília , Silanos/química , Silicones/química , Siloxanas/química , Propriedades de Superfície
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