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1.
BMC Public Health ; 19(1): 663, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146713

RESUMO

BACKGROUND: Previous studies on asthma mortality and hospitalizations in Reunion Island indicate that this French territory is particularly affected by this pathology. Epidemiological studies conducted in schools also show higher prevalence rates in Reunion than in Mainland France. However, no estimates are provided on the prevalence of asthma among adults. In 2016, a cross-sectional survey was conducted to estimate the prevalence of asthma and to identify its associated factors in the adult population of Reunion Island. METHODS: A random sample of 2419 individuals, aged 18-44 years, was interviewed by telephone using a standardized, nationally validated questionnaire. Information was collected on the respiratory symptoms, description of asthma attacks and triggering factors for declared asthmatics, as well as data on the indoor and outdoor home environment. "Current asthma" was defined as an individual declaring, at the time of the survey, having already suffered from asthma at some point during his/her life, whose asthma was confirmed by a doctor, and who had experienced an asthma attack in the last 12 months or had been treated for asthma in the last 12 months. "Current suspected asthma" was defined as an individual presenting, in the 12 months preceding the study, groups of symptoms suggestive of asthma consistent with the literature. RESULTS: The estimated prevalence of asthma was 5.4% [4.3-6.5]. After adjustment, women, obesity, a family member with asthma, tenure in current residence and presence of indoor home heating were associated with asthma. The prevalence of symptoms suggestive of asthma was 12.0% [10.2-13.8]. After adjustment, marital status, passive smoking, use of insecticide sprays, presence of mold in the home and external sources of atmospheric nuisance were associated with the prevalence of suspected asthma. CONCLUSION: Preventive actions including asthma diagnosis, promotion of individual measures to reduce risk exposure as well as the development of study to improve knowledge on indoor air allergens are recommended.


Assuntos
Asma/epidemiologia , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Reunião/epidemiologia , Fatores de Risco , Adulto Jovem
3.
Opt Lett ; 42(18): 3682-3685, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28914932

RESUMO

We report on the direct experimental observation of the 7pP23/2→7dD2 optical transitions in 209 and 210 francium isotopes. By continuously monitoring the fluorescence emitted by the isotopes collected in a magneto-optical trap (MOT), the electric dipole transitions 7pP23/2→7dD25/2 of Fr209, not yet experimentally observed, and 7pP23/2→7dD25/2, 7pP23/2→7dD25/2 of Fr210 were detected as sub-Doppler depletion dips of the cold atom population. This approach allowed unambiguous identification of the excited state hyperfine structures, even in the absence of a large stable vapor. Our findings demonstrate the effectiveness and the flexibility of fluorescence monitoring of trap depletion upon laser excitation, and broaden the experimental knowledge of francium isotopes and their electronic and nuclear properties. These results will have a relevant impact on ongoing researches for low-energy testing of fundamental symmetries with francium, from atomic parity non-conservation to the electron dipole moment.

5.
NMR Biomed ; 29(4): 377-86, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26777799

RESUMO

Hyperpolarized (13)C MR measurements have the potential to display non-linear kinetics. We have developed an approach to describe possible non-first-order kinetics of hyperpolarized [1-(13)C] pyruvate employing a system of differential equations that agrees with the principle of conservation of mass of the hyperpolarized signal. Simultaneous fitting to a second-order model for conversion of [1-(13)C] pyruvate to bicarbonate, lactate and alanine was well described in the isolated rat heart perfused with Krebs buffer containing glucose as sole energy substrate, or glucose supplemented with pyruvate. Second-order modeling yielded significantly improved fits of pyruvate-bicarbonate kinetics compared with the more traditionally used first-order model and suggested time-dependent decreases in pyruvate-bicarbonate flux. Second-order modeling gave time-dependent changes in forward and reverse reaction kinetics of pyruvate-lactate exchange and pyruvate-alanine exchange in both groups of hearts during the infusion of pyruvate; however, the fits were not significantly improved with respect to a traditional first-order model. The mechanism giving rise to second-order pyruvate dehydrogenase (PDH) kinetics was explored experimentally using surface fluorescence measurements of nicotinamide adenine dinucleotide reduced form (NADH) performed under the same conditions, demonstrating a significant increase of NADH during pyruvate infusion. This suggests a simultaneous depletion of available mitochondrial NAD(+) (the cofactor for PDH), consistent with the non-linear nature of the kinetics. NADH levels returned to baseline following cessation of the pyruvate infusion, suggesting this to be a transient effect.


Assuntos
Coração/fisiologia , Soluções Isotônicas/metabolismo , Dinâmica não Linear , Perfusão , Ácido Pirúvico/metabolismo , Animais , Isótopos de Carbono , Soluções Cristaloides , Fluorescência , Glucose , Cinética , Espectroscopia de Ressonância Magnética , Masculino , NAD/metabolismo , Ratos Wistar
6.
J Chem Phys ; 141(13): 134201, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25296799

RESUMO

We present here the first evidence of photodesorption induced by low-intensity non-resonant light from an yttrium thin foil, which works as a neutralizer for Rb and Fr ions beam. Neutral atoms are suddenly ejected from the metal surface in a pulsed regime upon illumination with a broadband flash light and then released in the free volume of a pyrex cells. Here atoms are captured by a Magneto-Optical Trap (MOT), which is effectively loaded by the photodesorption. Loading times of the order of the flash rise time are measured. Desorption is also obtained in the continuous regime, by exploiting CW visible illumination of the metallic neutralizer surface. We demonstrate that at lower CW light intensities vacuum conditions are not perturbed by the photodesorption and hence the MOT dynamics remains unaffected, while the trap population increases thanks to the incoming desorbed atoms flux. Even with the Y foil at room temperature and hence with no trapped atoms, upon visible illumination, the number of trapped atoms reaches 10(5). The experimental data are then analyzed by means of an analytical rate equation model, which allows the analysis of this phenomenon and its dynamics and allows the determination of critical experimental parameters and the test of the procedure in the framework of radioactive Francium trapping. In this view, together with an extensive investigation of the phenomenon with (85)Rb, the first demonstration of the photodesorption-aided loading of a (210)Fr MOT is shown.

7.
Rev Sci Instrum ; 93(8): 083001, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050098

RESUMO

The Selective Production of Exotic Species project is under construction at Laboratori Nazionali di Legnaro-INFN. The aim of the collaboration is to produce highly pure Radioactive Ion Beams (RIBs) from fission fragments of a uranium carbide (UCx) target activated by a cyclotron proton beam. In order to select a specific atomic species, the main tool to be applied is the resonant laser ionization technique. We have just completed the installation of a dedicated all solid state laser system whose elements are tunable to transitions of all the elements/isotopes of interest for the project. The new laser system is based on three Titanium:sapphire laser sources, independently pumped by three Nd:YLF pump lasers, and it can be coupled to two high harmonic generation (second harmonic generation, third harmonic generation, and fourth harmonic generation) setups. The power, wavelength, and position of the laser beams are continuously monitored and stabilized by using automated active systems to improve the beam production stability of RIBs. This paper presents the main features of the laser system and examples of application of a laser ion source, including a first demonstration of photoionization of stable silver, one of the most requested elements for RIB application.

8.
Cytometry A ; 79(1): 14-24, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21182179

RESUMO

During the last decades, extended characterizations were performed of human full-term cord blood (hTCB) cells, but little information is available on human early preterm cord blood (hEPCB) hematopoietic stem cells (HSCs). In our study, we analyzed by flow cytometry 19 hEPCB and 17 hTCB samples. First, we observed that the percentage of CD34(Pos)CD45(Dim) cells was higher in hEPCB compared with hTCB and that it decreased during 16th-20th week of pregnancy. Within the CD34(Pos)CD45(Dim) population, we examined the expression of CD29, CD31, CD38, CD90, CD117, CD133, CD135, CD200, CD243, and CD338. We found that CD135 intensity and CD243(Pos) cells percentage were lower in hEPCB compared with hTCB. As to CD38, we observed that hEPCB samples were richer in undifferentiated CD34(Pos)CD45(Dim)CD38(Neg) HSCs compared with hTCB counterparts. We also compared the expression of the above-mentioned molecules in undifferentiated and committed HSCs residing in hEPCB and hTCB. In particular, although CD34(Pos)CD45(Dim)CD38(Pos) HSCs from both hEPCB and hTCB expressed relatively higher amounts of CD29, CD71, and CD135 compared with CD34(Pos)CD45(Dim)CD38(Neg) cells, a higher expression of CD31 was restricted to CD34(Pos)CD45(Dim)CD38(Pos) cells from hEPCB samples, and a higher expression of CD117 was demonstrated in CD34(Pos)CD45(Dim)CD38(Pos) cells from hTCB samples. Moreover, our data showed that CD34(Pos)CD45(Dim) cell population from hEPCB displayed higher percent of undifferentiated CD38(Neg)CD133(Pos) cells compared with hTCB samples. Finally, analyzing monocytes and lymphocytes within the two samples, we observed that T-cell percentages were higher in hTCB, whereas B-cell percentages were higher in hEPCB. We, therefore, studied the B-cell lineage maturation and found a higher percent of pro-B and pre-B cells in hEPCB compared with hTCB samples. Taken together, these results evidence the hematopoietic peculiarity of hEPCB, potentially useful for highlighting early steps of human hematolymphopoiesis as well as for developing novel strategies of stem cell-based therapy.


Assuntos
Antígenos CD34/sangue , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , ADP-Ribosil Ciclase 1/sangue , Linfócitos B/química , Linfócitos B/citologia , Linhagem da Célula , Criopreservação , Feminino , Citometria de Fluxo/métodos , Idade Gestacional , Células-Tronco Hematopoéticas/química , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Antígenos Comuns de Leucócito/sangue , Subpopulações de Linfócitos/química , Subpopulações de Linfócitos/citologia , Monócitos/química , Monócitos/citologia , Gravidez , Linfócitos T/química , Linfócitos T/citologia
9.
Opt Lett ; 34(17): 2643-5, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19724518

RESUMO

We propose and experimentally implement a method, based on light-induced atomic desorption, for controlled generation of large sodium densities in siloxane-coated cells, kept at room temperature. An array of blue LEDs is used to desorb sodium atoms from the cell walls. The required atomic vapor density is achieved and stabilized by controlling the LED power through the feedback given by the sodium fluorescence. We show that sodium densities corresponding to about 400 K can be obtained and kept stable for a long time with less than 6 mW of LED light power. Moreover, this technique allows for precise vapor density modulation with a frequency of tenths of hertz, which is not possible using traditional heating methods.

10.
Leuk Res ; 32(2): 323-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17586045

RESUMO

Mycoplasma contamination is a deleterious event for a cell culture laboratory due to the ability of this microorganism to contaminate cell culture leading up to the production of false data or, in the worst cases, to the loss of cell culture itself. Fortunately, mycoplasma can be eradicated by the use of antibiotics, but early detection of contamination is peremptory. Here, we propose the use of a sensitive and specific biochemical test named MycoAlert. In particular, as regards cell cultures not yet treated with antibiotics, sensitivity, specificity, positive and negative predictive values of MycoAlert assay gave excellent scores of 100%, 97%, 89% and 100%, respectively.


Assuntos
DNA Bacteriano/análise , Técnicas Microbiológicas , Mycoplasma/isolamento & purificação , Animais , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Humanos , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
11.
Leuk Res ; 32(8): 1196-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18262645

RESUMO

Among histological aggressive non-Hodgkin lymphomas (NHL), the overall risk of central nervous system (CNS) relapse is approximately 5%, a figure which is too low to offer prophylaxis to all patients. The aim of this work is to demonstrate the utility of flow cytometry (FCM) in detecting occult leptomeningeal disease in this subtype of NHL. We studied cerebrospinal fluid (CSF) involvement in 42 newly diagnosed aggressive NHL patients at risk for CNS involvement. We used multicolour FCM to detect CSF infiltrating neoplastic cells. Among the 42 patients studied, 11 had CSF involvement as detected by FCM. Of these, only four were also positive for conventional morphology (p=0.046). These results designate that FCM as the first choice technique in NHL CSF clinical cell analysis.


Assuntos
Citometria de Fluxo/métodos , Linfoma de Células B/líquido cefalorraquidiano , Neoplasias Meníngeas/líquido cefalorraquidiano , Citodiagnóstico , Humanos
12.
Opt Express ; 16(2): 1377-84, 2008 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-18542210

RESUMO

We report reversible phase transformations in Rb loaded-porous glass irradiated with weak laser light which allow us to realize image storage on it. The effect is due to photo-induced changes of Rb distribution inside the glass pores, where atomic photodetachment and confinement produce either formation or evaporation of Rb nanoclusters. These processes depend on light frequency and intensity making controllable by light the porous glass transparency. We demonstrate that porous glass doped with Rb can be used as a support to record a light pulse for a long time as well as to remember the order of light colors in an illumination sequence.


Assuntos
Vidro/química , Armazenamento e Recuperação da Informação/métodos , Nanoestruturas/química , Óptica e Fotônica/instrumentação , Rubídio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Transição de Fase , Porosidade
14.
Clin Ter ; 158(3): 239-48, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-17612285

RESUMO

The OLR1 gene encodes a cell-surface endocytosis receptor (LOX-1) for oxidized low density lipoprotein (OxLDL). LDL is oxidized in vascular endothelial cells to a highly injurious product that results in endothelial cell injury, which is implicated in the development of atherosclerosis. Vascular endothelial cells also internalize and degrade oxLDL though the OLR1 receptor. This receptor is upregulated by ox-LDL itself and by angiotensin II, endothelin, cytokines, and shear stress, important factors of atherosclerosis. This receptor is upregulated in the arteries of hypertensive, dyslipidemic, and diabetic animals. Two independent studies have demonstrated genetic association between polymorphisms in the OLR1 gene and myocardial infarction. Based on genetic and functional studies we propose LOX-1 as a novel biomarker and target in cardiovascular disease diagnosis and prevention.


Assuntos
Aminoácido Oxirredutases/genética , Aterosclerose/genética , Doenças Cardiovasculares/genética , Aminoácido Oxirredutases/fisiologia , Animais , Humanos
15.
Rev Sci Instrum ; 88(11): 113303, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29195346

RESUMO

Low energy threshold detectors are necessary in many frontier fields of the experimental physics. In this work, we present a novel detection approach based on pure or doped matrices of inert gases solidified at cryogenic temperatures. The small energy release of the incident particle can be transferred directly (in pure crystals) or through a laser-driven ionization (in doped materials) to the electrons of the medium that are then converted into free electrons. The charge collection process of the electrons that consists in their drift within the crystal and their extraction through the solid-vacuum interface gives rise to an electric signal that we exploit for preliminary tests of charge collection and crystal quality. Such tests are carried out in different matrices of neon and methane using an UV-assisted apparatus for electron injection in crystals.

16.
Am J Med ; 110(5): 361-9, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11286950

RESUMO

PURPOSE: Although coronary artery disease is a frequent cause of left bundle branch block, the prognostic value of myocardial ischemia in patients with this conduction abnormality has not been defined. We investigated the value of pharmacologic stress echocardiography in risk stratification of patients with left bundle branch block. PATIENTS AND METHODS: Three hundred eighty-seven patients [230 men and 157 women, mean (+/- SD) age, 64 +/- 9 years] with complete left bundle branch block on the resting electrocardiogram underwent dobutamine (n = 217) or dipyridamole (n = 170) stress echocardiography to evaluate suspected or known coronary artery disease. A summary wall motion score (on a one to four scale) was calculated. The primary end points were cardiac death and nonfatal myocardial infarction. RESULTS: A positive echocardiographic result (evidence of ischemia) was detected in 109 (28%) patients. During a mean follow-up of 29 +/- 26 months, there were 21 cardiac deaths and 20 myocardial infarctions, 63 patients underwent coronary revascularization, and 1 patient received a heart transplant. In a multivariate analysis, four clinical and echocardiographic variables were associated with increased risk of cardiac death: resting wall motion score index [hazard ratio (HR) = 7.5 per unit; 95% confidence interval (CI), 2.8 to 20; P = 0.001], previous myocardial infarction (HR = 2.9; 95% CI, 1.1 to 7.3; P = 0.02), diabetes (HR = 2.7; 95% CI, 1.1 to 6.6; P = 0.03), and the change in wall motion score index from rest to peak stress (HR = 3.0 per unit; 95% CI, 1.0 to 8.6; P = 0.04). The 5-year survival was 77% in the ischemic group and 92% in the nonischemic group (P = 0.02). Four variables were associated with increased risk of cardiac death or infarction: previous myocardial infarction (HR = 3.4; 95% CI, 1.7 to 6.8; P = 0.0005), diabetes (HR = 2.4; 95% CI, 1.2 to 4.6; P = 0.01), resting wall motion score index (HR = 2.2 per unit; 95% CI, 1.1 to 4.1; P = 0.02), and positive echocardiographic result (HR = 2.2; 95% CI, 1.1 to 4.5; P = 0.03). The 5-year infarction-free survival was 60% in the ischemic group and 87% in the nonischemic group (P < 0.0001). Stress echocardiography significantly improved risk stratification in patients without previous myocardial infarction (P = 0.0001), but not in those with previous myocardial infarction (P = 0.08). In particular, it provided additional value over clinical and resting echocardiographic findings in predicting cardiac events among patients without previous infarction. CONCLUSIONS: Myocardial ischemia during pharmacologic stress echocardiography is a strong prognostic predictor in patients with left bundle branch block, particularly in those without previous myocardial infarction.


Assuntos
Agonistas Adrenérgicos beta/efeitos adversos , Bloqueio de Ramo/diagnóstico por imagem , Dobutamina/efeitos adversos , Ecocardiografia , Isquemia Miocárdica/induzido quimicamente , Idoso , Bloqueio de Ramo/mortalidade , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Risco
17.
Bone Marrow Transplant ; 12 Suppl 1: 106-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8374547

RESUMO

In patients with thalassemia major iron overload leads to symptoms of cardiac failure and it is the most frequent cause of death. A sub group of asymptomatic thalassemic patients (Th Pts) who underwent bone marrow transplantation (BMT) and who presented persistently high serum ferritin level and heavy haemosiderosis were subjected to cardiological study to evaluate possible iron-related cardiac disease. We report here preliminary results obtained from the Echocardiographic studies carried out at baseline and at eight months follow-up in a group of ex-thalassemic after transplant who underwent phlebotomy in the attempt to reduce the iron overload.


Assuntos
Sangria , Transplante de Medula Óssea , Ecocardiografia , Insuficiência Cardíaca/fisiopatologia , Hemocromatose/terapia , Reação Transfusional , Talassemia beta/fisiopatologia , Adolescente , Adulto , Criança , Terapia Combinada , Feminino , Seguimentos , Insuficiência Cardíaca/etiologia , Hemocromatose/complicações , Hemocromatose/fisiopatologia , Humanos , Masculino , Período Pós-Operatório , Talassemia beta/complicações , Talassemia beta/cirurgia , Talassemia beta/terapia
18.
Bone Marrow Transplant ; 17(1): 119-20, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8673044

RESUMO

We report a thalassemia patient suffering from congenital transposition of the great arteries, surgically corrected according to Mustard technique at the age of 4 months, who underwent bone marrow transplantation. Despite a syncopal episode occurring during the first day after marrow infusion the transplant was successful. Thirty-two months later, normalization of hematologic parameters was observed together with a substantial improvement in cardiac function.


Assuntos
Transplante de Medula Óssea , Talassemia/terapia , Transposição dos Grandes Vasos/fisiopatologia , Feminino , Humanos , Talassemia/fisiopatologia
19.
Bone Marrow Transplant ; 12 Suppl 1: 14-5, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8374553

RESUMO

In patients with Thalassaemia Major the iron overload with alteration both of systolic and diastolic properties of left and right ventricles finally leads to symptoms of cardiac failure and is the most frequent cause of death in these patients. In the majority of asymptomatic thalassemic patients with normal myocardial mass it is possible to demonstrate an alteration of the diastolic function both with echocardiographic study and with radionuclide angiography (subclinical cardiac disease). We have also demonstrated in "ex thalassemics" with stable and heavy iron overload in the subclinical cardiac disease phase a subnormal systolic function and a slight impairment of the contractility state. Therefore our purpose was to evaluate cardiac performance emphasising the contractility properties of the left ventricle during moderate inotropic stimulation with dobutamine in thalassemic patients in subclinical cardiac disease. We are now also using this test to evaluate cardiac performance in adults thalassemic patients as a screening for marrow transplantation procedure. Dobutamine is a sympathomimetic drug (beta 1 agonist) that increases myocardial contractility and at high doses also systolic arterial blood pressure and heart rate. The half-life is extremely short and at low doses the drug has no major side effects. Continuous intravenous dobutamine infusion is largely used in the therapeutic field to treat cardiac failure and it is reported to be a very efficacious and safe therapeutic agent. Recently dobutamine stress echocardiography was reported to be an accurate non-invasive diagnostic technique for detecting cardiac dysfunction in adults with coronary artery disease (Dobutamine is used for this purpose at high dose to increase the myocardial oxygen consumption).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diástole , Dobutamina , Ecocardiografia , Talassemia beta/fisiopatologia , Adolescente , Adulto , Terapia por Quelação , Criança , Terapia Combinada , Desferroxamina/uso terapêutico , Feminino , Insuficiência Cardíaca/etiologia , Hemossiderose/etiologia , Hemossiderose/fisiopatologia , Humanos , Ferro , Masculino , Reação Transfusional , Talassemia beta/complicações , Talassemia beta/terapia
20.
Bone Marrow Transplant ; 13(6): 827-9, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7920322

RESUMO

We report a case of acute cardiac tamponade without concurrent myocardial disease occurring in a thalassemia patient early after bone marrow transplantation. The pericardial effusion was preceded by an episode of junctional tachycardia. Repeated evaluation by echocardiography was done shortly after the patient developed the arrhythmia and permitted a detailed, timed observation of the event and description of the symptoms.


Assuntos
Tamponamento Cardíaco/etiologia , Talassemia beta/complicações , Transplante de Medula Óssea/efeitos adversos , Tamponamento Cardíaco/diagnóstico por imagem , Tamponamento Cardíaco/fisiopatologia , Criança , Ecocardiografia , Humanos , Masculino , Talassemia beta/terapia
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