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1.
Ig Sanita Pubbl ; 80(2): 30-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38739439

RESUMO

Falls are a widespread concern in hospitals settings. In Italy, falls are the fourth frequent damage claim type after surgical, diagnostic and therapeutic error and 90% of falls are avoidable. The first necessary action for the prevention of falls consists in identifying the possible risk factors, in relation to the characteristics of the patient and those of the environment and the structure that hosts him, in terms of safety, organization and adequacy of the process welfare. In this work we wanted to evaluate the extent, frequency and characteristics of the phenomenon of falls in the population hospitalized at the Local Health Authority called "Roma 2", with the aim of analyzing the critical issues to allow the identification of possible preventive and improvement interventions as well as reducing the risk of falls.


Assuntos
Acidentes por Quedas , Gestão de Riscos , Humanos , Acidentes por Quedas/prevenção & controle , Acidentes por Quedas/estatística & dados numéricos , Itália , Gestão de Riscos/métodos , Idoso , Masculino , Feminino , Fatores de Risco , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Adulto
2.
Eur J Clin Microbiol Infect Dis ; 42(8): 945-950, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37169944

RESUMO

To date, few reports have evaluated the pneumococcal vaccination status in cirrhotic patients. No data are available for European countries. We have explored this topic and the potential independent predictors motivating lack of vaccination in Italy. Between January 1st and June 30th 2022, 1419 cirrhotic patients of any etiology were consecutively enrolled in an observational, prospective study at 8 referral centers in Italy. Adjusted odds ratios (ORs) for the association with lack of vaccination were evaluated by multiple logistic regression analysis. Overall vaccine coverage was 17.9% (8.9% in patients < 65 years of age and 27.1% in those aged ≥ 65 years; p < 0.001). Among the 1165 unvaccinated patients, 1068 (91.7%) reported lack of information regarding vaccination as the reason for not having undergone vaccination. Independent predictors associated with lack of vaccination were age < 65 years (OR 3.39, CI 95% 2.41-4.76) and a higher number of schooling years (OR 2.14, CI 95% 1.58-2.91); alcoholic etiology resulted only marginally associated (OR 1.91, CI 95% 1.03-3.52). These findings establish evidence on how pneumococcal vaccination status in Italy is largely suboptimal among cirrhotic patients. These results raise concern, considering the severe outcomes of pneumococcal infection in patients with chronic liver diseases.


Assuntos
Infecções Pneumocócicas , Vacinas Pneumocócicas , Idoso , Humanos , Itália/epidemiologia , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Estudos Prospectivos , Vacinação , Pessoa de Meia-Idade
3.
J Med Virol ; 93(4): 2446-2452, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33368427

RESUMO

We have evaluated flu vaccine coverage and variables associated with the lack of vaccination in cirrhotic subjects with particular attention to the cirrhosis etiology. Cirrhotic subjects consecutively referring to eight Italian centers were prospectively enrolled for a 6-month period in 2019. Subjects were asked if they had received a flu vaccine in the last 12 months. Multiple logistic regression analysis was performed to identify independent predictors of lack of vaccination. A total of 818 cases were recruited. The overall vaccine coverage was 39.6% (26.9% in those younger than 65 years and 51.9% in those older than 64 years; p < 0.001). Age < 65 years (odds ratio [OR] = 2.38; 95% confidence interval [CI] = 1.68-3.36), alcoholic etiology (OR = 2.40; 95% CI = 1.49-3.85), birth abroad (OR = 2.7; 95% CI = 1.10-6.61), and residence in South/Sardinia island (OR = 1.66; 95% CI = 1.14-2.42) all resulted independent predictors of the likelihood of lack of vaccination. The lack of information regarding the vaccine as the reason for no vaccination was reported by 71.4% of foreigners and by 34.7% of natives (p < 0.001). In conclusion, much work still should be done to improve coverage among groups at higher risk of lack of vaccination identified in this survey. The ongoing SARS-CoV-2 pandemic may represent one more alert for improving seasonal flu vaccine coverage to avoid further stress to the National Health System.


Assuntos
COVID-19/epidemiologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/complicações , Cirrose Hepática/epidemiologia , Cobertura Vacinal/estatística & dados numéricos , Idoso , COVID-19/virologia , Feminino , Humanos , Influenza Humana/epidemiologia , Cirrose Hepática/etiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pandemias , Prevalência , SARS-CoV-2/isolamento & purificação , Estações do Ano , Vacinação/estatística & dados numéricos
4.
Rev Cardiovasc Med ; 22(4): 1197-1204, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34957763

RESUMO

Atrial fibrillation (AF) can lead to embolic stroke and in subjects with non-valvular AF most of thrombi are sited in the left atrial appendage (LAA). LAA is a structure located in the free wall of heart with a wide variable and complex anatomy. LAA occlusion (LAAO) could be taken in consideration in subjects with non-valvular AF and who cannot have long-term anticoagulant therapy. It is a complex preventive procedure given the high variability of patients characteristics and several LAAO devices available nowadays. Moreover, the ideal postprocedural antithrombotic strategy is still unclear. In this review we aim to describe clinical features of patients committed for LAA occlusion and the function of multimodality imaging in subjects selection, procedural management and follow up.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Acidente Vascular Cerebral , Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Humanos , Imagem Multimodal , Seleção de Pacientes , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Resultado do Tratamento
5.
Monaldi Arch Chest Dis ; 88(3): 976, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30183157

RESUMO

Mounting evidence suggests that hormonal deficiencies (HD) have an important role in chronic heart failure (CHF). In particular, androgen depletion is common in men with CHF and is associated with increased morbidity and mortality. This review summarizes the current understanding of the complex relationship between CHF and testosterone, focusing on evidence derived from clinical trials that have investigated the role of testosterone in the treatment of CHF. A greater comprehension of this area will allow researchers and clinicians to plan future studies that improve current strategies to reduce mortality in this high-risk population. Online databases PubMed (Medline), Web of Science, and Scopus were searched for manuscripts published prior to June 2018 using key words "heart failure" AND "testosterone" OR "anabolism" OR "hormone" OR "replacement treatment". Manuscripts were collated, studied and carried forward for discussion where appropriate. In summary, findings from the literature demonstrate that testosterone treatment in CHF is a promising topic that requires further investigation.


Assuntos
Androgênios/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Testosterona/uso terapêutico , Doença Crônica , Humanos
6.
Monaldi Arch Chest Dis ; 88(3): 975, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30183158

RESUMO

Hormonal abnormalities are quite common in chronic heart failure (CHF). The most studied hormonal axis in CHF is the impairment of Growth Hormone (GH)/Insulin Growth Factor-1(IGF-1), which in turn is defined either by a blunted response to GH stimulation test or low serum IGF-1 values.  Several independent groups reported that the presence of an abnormal GH/IGF-1 status in CHF is associated with a more severe disease, impaired functional capacity and reduced Survival rates. After the first encouraging results, double -blind controlled trials showed a neutral effect of the GH administration in patients. However, further studies reported positive results, when a GH-therapy is implemented only in those patients presenting a GH deficiency (replacement therapy).


Assuntos
Insuficiência Cardíaca/metabolismo , Hormônio do Crescimento Humano/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Doença Crônica , Insuficiência Cardíaca/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Humanos
7.
Phys Rev Lett ; 119(2): 023901, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28753345

RESUMO

Single nanoparticles are shown to develop a localized acoustic resonance, the bouncing mode, when placed on a substrate. If both substrate and nanoparticle are noble metals, plasmonic coupling of the nanoparticle to its image charges in the film induces tight light confinement in the nanogap. This yields ultrastrong "acoustoplasmonic" coupling with a figure of merit 7 orders of magnitude higher than conventional acousto-optic modulators. The plasmons thus act as a local vibrational probe of the contact geometry. A simple analytical mechanical model is found to describe the bouncing mode in terms of the nanoscale structure, allowing transient pump-probe spectroscopy to directly measure the contact area for individual nanoparticles.

8.
Ann Hematol ; 96(8): 1297-1302, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28585070

RESUMO

The most common causes of morbidity and mortality in myeloproliferative neoplasms (MPN) are thrombotic and hemorrhagic complications. The JAK2V617F mutation, commonly found in MPN, correlates with several clinical and laboratory characteristics even if the relevance of JAK2V617F allele burden in the natural history of these diseases is unclear. In this study we searched, a relation between thrombotic and hemorrhagic complications and JAK2V617F allele burden level in MPN patients. We evaluated 253 consecutive MPN [121 essential thrombocythemia (ET), 124 polycythemia vera (PV), and 8 primary myelofibrosis (PMF)] patients in whom the JAK2V617F allele burden was available, all studied and followed (median 8.8 years) in our department. Patients were stratified accordingly to their JAK2V617F allele burden, into four quartiles (1st <25%, 2nd 26-50%, 3rd 51-75%, and 4th >75%). Significantly higher incidence of thromboses (p = 0.001) and hemorrhages (p < 0.001) during follow-up has been observed in higher quartiles when compared to lower ones. Thrombosis- and hemorrhage-free survivals were poorer in patients belonging to the highest quartile. Our data suggest that MPN patients with JAK2V617F allele burden higher than 75% have to be considered as high risk patients, being prone to develop thrombo-hemorrhagic complications during the disease course.


Assuntos
Hemorragia/complicações , Janus Quinase 2/genética , Mutação de Sentido Incorreto , Transtornos Mieloproliferativos/genética , Trombose/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Feminino , Frequência do Gene , Hemorragia/diagnóstico , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Transtornos Mieloproliferativos/complicações , Policitemia Vera/complicações , Policitemia Vera/genética , Mielofibrose Primária/complicações , Mielofibrose Primária/genética , Modelos de Riscos Proporcionais , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Trombocitemia Essencial/complicações , Trombocitemia Essencial/genética , Trombose/diagnóstico
9.
Nano Lett ; 16(10): 6311-6316, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27648834

RESUMO

Fano resonances are central features in the responses of many systems including atoms, molecules, and nanomaterials. They arise as a consequence of interferences between two channels, most frequently associated with two system modes. In plasmonic materials, Fano interferences between optical modes have been shown, experimentally and theoretically, to induce narrow features in their scattering spectra. By investigating individual silver-gold heterodimers, we first experimentally demonstrate that Fano interference is also a key effect in the optical absorption of plasmonic nano-objects, in agreement with theoretical predictions. Conversely to previously investigated systems, the two interacting modes at the origin of absorptive Fano effect are mostly localized on either one or the other dimer component. Experimental results were obtained by selectively monitoring the optical absorption of one dimer component using a two-color nonlinear time-resolved technique. This also opens the way to full optical far-field noncontact investigations of charge or energy exchanges between nano-objects with a spatial resolution much smaller than the optical wavelength.

10.
Cancer Causes Control ; 27(5): 595-606, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27076059

RESUMO

PURPOSE: High intake of meat has been inconsistently associated with increased risk of non-Hodgkin lymphoma (NHL). We carried out a meta-analysis to summarize the evidence of published observational studies reporting association between red meat and processed meat intake and NHL risk. METHODS: Analytical studies reporting relative risks with 95 % confidence intervals (95 % CI) for the association between intake of red and/or processed meat and NHL or major histological subtypes were eligible. We conducted random-effects meta-analysis comparing lowest and highest intake categories and dose-response meta-analysis when risk estimates and intake levels were available for more than three exposure classes. RESULTS: Fourteen studies (four cohort and ten case-control) were included in the meta-analysis, involving a total of 10,121 NHL cases. The overall relative risks of NHL for the highest versus the lowest category of consumption were 1.14 (95 % CI 1.03, 1.26) for red meat and 1.06 (95 % CI 0.98, 1.15) for processed meat. Significant associations were present when the analysis was restricted to case-control studies but not when restricted to cohort studies. No significant associations were found for major NHL etiological subtypes. Dose-response meta-analysis could be based only on eight studies that provided sufficient data, and compared to no meat consumption, the overall NHL relative risk increased nonlinearly with increased daily intake of red meat. CONCLUSION: The observed positive association between red meat consumption and NHL is mainly supported by the effect estimates coming from case-control studies and is affected by multiple sources of heterogeneity. This meta-analysis provided mixed and inconclusive evidences on the supposed relationship between red and processed meat consumption and NHL.


Assuntos
Linfoma não Hodgkin/epidemiologia , Carne/efeitos adversos , Estudos de Casos e Controles , Estudos de Coortes , Humanos , Linfoma não Hodgkin/etiologia , Estudos Observacionais como Assunto , Risco
11.
Eur J Haematol ; 97(6): 547-553, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27124643

RESUMO

OBJECTIVES: The main objective of the study was to evaluate the incidence of bleeding manifestations in heterozygotes for FX deficiency vs. unaffected family members. Secondary objective was to compare the prevalence of arterial or venous diseases found in the two groups. PATIENTS AND METHODS: A total of 128 heterozygote patients for FX deficiency were investigated. A total of 102 patients had FX Friuli; 26 patients had other forms of FX deficiency. At time of diagnosis, each patient was paired with an unaffected family member, matched by gender and age (±5). Patients and their normal counterparts were checked every 1-2 yr for a mean period of 23.5 yr. The occurrence of bleeding manifestations was recorded and scored. The occurrence of arterial diseases and venous thrombosis was also recorded as a secondary finding. RESULTS: A total of 38 heterozygote patients (29.7%) had one or more than one bleeding manifestation. The most frequent one was bleeding after tooth extraction or surgery. On the contrary, only three control subjects (2.3%) had documented hemorrhagic symptoms. There was a good correlation between bleeding and FX levels. Arterial disease (acute coronary syndromes, ischemic stroke, stable angina, peripheral arteries disease) was found in eight patients (6.3%) with FX deficiency and in seven unaffected subjects (5.5%). On the contrary, no venous thrombosis was seen in the affected group, whereas three cases (2.3%) of documented venous thrombosis were observed in the control group (two deep veins and one superficial vein). CONCLUSIONS: Heterozygotes FX deficiency may be accompanied by a mild bleeding tendency. This has important implications to assure a safe FX level in case of surgery or invasive procedures. Furthermore, mild FX deficiency seems to have no protective effect on arterial disease but does seem to protect from venous thrombosis.


Assuntos
Deficiência do Fator X/epidemiologia , Deficiência do Fator X/genética , Fator X/genética , Hemorragia/epidemiologia , Heterozigoto , Mutação , Deficiência do Fator X/complicações , Deficiência do Fator X/história , Feminino , Seguimentos , Hemorragia/diagnóstico , Hemorragia/etiologia , História do Século XX , História do Século XXI , Humanos , Masculino , Prevalência
12.
J Thromb Thrombolysis ; 42(4): 586-92, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27379499

RESUMO

Differential diagnosis between thrombotic thrombocytopenic purpura (TTP) and other thrombotic microangiopathies (TMA) is usually difficult because of frequently overlapping clinical presentations. Severely depressed ADAMTS13 activity (<10 %) seems distinctive for TTP because of its pathogenetic role. However a long debate exists in the literature about its sensibility and specificity. Our aim was to search for clinical differences between TMA patients referred to our laboratory, comparing them for protease activity <10 versus ≥10 %. ADAMTS13 activity ≥10 % patients (n = 73) showed a higher prevalence of drug- (p = 0.005) and cancer-associated (p < 0.001) TMA. Mean platelet count and renal dysfunction prevalence was lower (p < 0.001), while neurological impairment was more frequent (p = 0.001) in the <10 % ADAMTS13 activity group (n = 109), confirming previous literature findings. When taken neurological manifestations singularly, epilepsy (p = 0.04), focal motor deficit (p < 0.001) and cranial nerve palsy (p = 0.007) were more frequent in the <10 % activity group. In our case series, a <10 % ADAMTS13 activity depicts a group of patients with clinical features similar to TTP patients. Focal motor impairment or epileptic manifestations could further address toward a TTP diagnosis. Studies about treatment efficacy and follow-up are advised to determine whether laboratory findings can guide therapeutic decisions.


Assuntos
Proteína ADAMTS13/sangue , Doenças dos Nervos Cranianos/sangue , Epilepsia Motora Parcial/sangue , Microangiopatias Trombóticas/sangue , Doença Aguda , Adulto , Idoso , Doenças dos Nervos Cranianos/etiologia , Epilepsia Motora Parcial/etiologia , Feminino , Humanos , Nefropatias/sangue , Masculino , Volume Plaquetário Médio , Pessoa de Meia-Idade , Neoplasias/sangue , Microangiopatias Trombóticas/complicações
15.
Eur J Haematol ; 92(6): 497-501, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24460705

RESUMO

OBJECTIVES: Thrombotic thrombocytopenic purpura (TTP) is a rare and devastating hematologic disorder frequently associated with multiple organ failure and sometimes death. This syndrome is mainly associated with severe deficiency of ADAMTS13, a disintegrin and metalloprotease with thrombospondin (TSP)-1 repeats, cleaving high molecular weight von Willebrand Factor (ULVWF) multimers. Decreased plasma ADAMTS13 activity results in the accumulation of ULVWF multimers with consequent platelet activation. Recently, obesity has been considered as a potential independent risk factor for TTP, but the reason of this association is still unknown. METHODS AND RESULTS: We describe an unusual case of fatal recurrent TTP in a morbid obese female with non-alcoholic steatohepatitis (NASH) and severe ADAMTS13 activity deficiency due neither to an inhibitory autoantibody nor to a gene mutation. CONCLUSIONS: Visceral obesity is associated with non-alcoholic fatty liver disease (NAFLD) and NASH: we hypothesized that these conditions can influence ADAMTS13 antigen and activity. In fact, hepatic stellate cells (HSC) are the main producers of ADAMTS13, and a decrease in ADAMTS13 activity has been reported in liver disease.


Assuntos
Proteínas ADAM/deficiência , Hepatopatia Gordurosa não Alcoólica/etiologia , Obesidade/complicações , Púrpura Trombocitopênica Trombótica/complicações , Proteínas ADAM/genética , Proteínas ADAM/imunologia , Proteínas ADAM/metabolismo , Proteína ADAMTS13 , Adulto , Ativação Enzimática , Evolução Fatal , Feminino , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Contagem de Plaquetas , Púrpura Trombocitopênica Trombótica/diagnóstico
16.
Nano Lett ; 13(5): 2234-40, 2013 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-23611370

RESUMO

The dependence of the spectral width of the longitudinal localized surface plasmon resonance (LSPR) of individual gold nanorods protected by a silica shell is investigated as a function of their size. Experiments were performed using the spatial modulation spectroscopy technique that permits determination of both the spectral characteristics of the LSPR of an individual nanoparticle and its morphology. The measured LSPR is shown to broaden with reduction of both the nanorod length and its diameter, which is in contrast with the predictions of existing classical and quantum theoretical models. This behavior can be reproduced assuming the LSPR width linearly depends on the inverse of an effective length proportional to the square root of the particle surface with the same slope as that recently determined for silica-coated silver nanospheres.


Assuntos
Ouro/química , Nanopartículas/química , Nanotubos/química , Dióxido de Silício/química , Ressonância de Plasmônio de Superfície , Tamanho da Partícula , Propriedades de Superfície
17.
J Basic Clin Physiol Pharmacol ; 35(3): 111-119, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38619602

RESUMO

Hypoglycaemic syndromes are rare in apparently healthy individuals and their diagnosis can be a difficult challenge for clinicians as there are no shared guidelines that suggest how to approach patients with a suspect hypoglycaemic disorder. Since hypoglycaemia symptoms are common and nonspecific, it's necessary to document the Whipple Triad (signs and/or symptoms compatible with hypoglycaemia; relief of symptoms following glucose administration; low plasma glucose levels) before starting any procedure. Once the triad is documented, a meticulous anamnesis and laboratory tests (blood glucose, insulin, proinsulin, C-peptide, ß-hydroxybutyrate and anti-insulin antibodies) should be performed. Results can guide the physician towards further specific tests, concerning the suspected disease. In this review, we consider all current causes of hypoglycaemia, including rare diseases such as nesidioblastosis and Hirata's syndrome, describe appropriate tests for diagnosis and suggest strategies to differentiate hypoglycaemia aetiology.


Assuntos
Glicemia , Hipoglicemia , Humanos , Hipoglicemia/diagnóstico , Hipoglicemia/sangue , Diagnóstico Diferencial , Glicemia/análise , Insulina/administração & dosagem
19.
Eur J Haematol ; 91(2): 152-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23621110

RESUMO

BACKGROUND: The occurrence of a thrombotic event in congenital bleeding disorders has drawn considerable attention in recent years. Both patients with hemophilia and patients with von Willebrand disease and even those with rare coagulation disorders have been shown to present occasional thrombotic events. Little is known on the comparative prevalence of arterial vs. venous thrombosis in these patients. OBJECTIVES: The purpose of the present investigation was to evaluate the prevalence of arterial vs. venous occlusions in hemophilia A and B vs. FVII deficiency. METHODS: A time unlimited search of the literature was carried out using pertinent key words. Arterial or venous occlusions had to be proven by objective methods. RESULTS: Eighty-five patients with hemophilia A or B have been reported to have had an arterial occlusion vs. six cases of FVII deficiency. On the contrary, 34 patients with hemophilia A or B and 32 cases with FVII deficiency have been reported to have presented with a venous thrombosis. The ratios of arterial vs. venous thrombosis are 3.72, 1.13, and 2.50 for hemophilia A, hemophilia B, and hemophilia A + B combined, respectively, and 0.19 for FVII deficiency. CONCLUSIONS: Hemophilia A and hemophilia B do not protect from arterial occlusions (mainly acute coronary syndromes), whereas they assure some protection from venous thrombosis. The opposite seems true for FVII deficiency. The potential significance of this discrepancy is discussed.


Assuntos
Artérias/patologia , Deficiência do Fator VII/complicações , Hemofilia A/complicações , Hemofilia B/complicações , Trombose/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Trombose/epidemiologia , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia , Adulto Jovem
20.
Phys Chem Chem Phys ; 15(12): 4154-62, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23169302

RESUMO

Here we report on the visible luminescence of single gold nanospherical particles diffusing in water excited by a pulsed-laser at 488 nm. The signal studied by fluorescence correlation spectroscopy does not display the expected characteristics. The main deviation is obtained for the diffusion time that depends on the laser irradiance. Additional advanced methods of measurements have been implemented to further characterize the emission. These methods have allowed us to demonstrate that the luminescence does not blink even in the picosecond domain and that it does not photobleach either. The comparison between the signals obtained under pulsed and continuous excitations at the same wavelength suggests that the increase in the particle temperature plays a role in the non-linear increase in the luminescence intensity with the excitation power. As in the case of two-photon excited luminescence, it implies that a model describing the luminescence process for a single particle diffusing in liquid must take into account the whole system composed of the gold particle, the capping ligands and the surrounding water.

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