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1.
Phys Rev Lett ; 131(4): 041403, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566847

RESUMO

In this Letter, we present the design and performance of the frequency-dependent squeezed vacuum source that will be used for the broadband quantum noise reduction of the Advanced Virgo Plus gravitational-wave detector in the upcoming observation run. The frequency-dependent squeezed field is generated by a phase rotation of a frequency-independent squeezed state through a 285 m long, high-finesse, near-detuned optical resonator. With about 8.5 dB of generated squeezing, up to 5.6 dB of quantum noise suppression has been measured at high frequency while close to the filter cavity resonance frequency, the intracavity losses limit this value to about 2 dB. Frequency-dependent squeezing is produced with a rotation frequency stability of about 6 Hz rms, which is maintained over the long term. The achieved results fulfill the frequency dependent squeezed vacuum source requirements for Advanced Virgo Plus. With the current squeezing source, considering also the estimated squeezing degradation induced by the interferometer, we expect a reduction of the quantum shot noise and radiation pressure noise of up to 4.5 dB and 2 dB, respectively.

2.
Phys Rev Lett ; 125(13): 131101, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034506

RESUMO

The quantum radiation pressure and the quantum shot noise in laser-interferometric gravitational wave detectors constitute a macroscopic manifestation of the Heisenberg inequality. If quantum shot noise can be easily observed, the observation of quantum radiation pressure noise has been elusive, so far, due to the technical noise competing with quantum effects. Here, we discuss the evidence of quantum radiation pressure noise in the Advanced Virgo gravitational wave detector. In our experiment, we inject squeezed vacuum states of light into the interferometer in order to manipulate the quantum backaction on the 42 kg mirrors and observe the corresponding quantum noise driven displacement at frequencies between 30 and 70 Hz. The experimental data, obtained in various interferometer configurations, is tested against the Advanced Virgo detector quantum noise model which confirmed the measured magnitude of quantum radiation pressure noise.

3.
Phys Rev Lett ; 123(23): 231108, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868444

RESUMO

Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of squeezed vacuum states of light into the interferometer's dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1 dB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%-8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the third joint LIGO-Virgo observation run O3 squeezing was applied for more than 99% of the science time. During this period several gravitational-wave candidates have been recorded.

4.
Lupus ; 25(5): 479-85, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26657216

RESUMO

BACKGROUND: Patients with antiphospholipid syndrome (APS) often have thrombotic recurrences, sometimes despite appropriate ongoing anticoagulant treatment. Identifying APS vascular patients at high risk for thrombotic recurrences is still an unsolved issue. OBJECTIVES: To report the real-life experience of thrombotic recurrences in APS patients included in the Piedmont observational cohort study, and evaluate clinical and laboratory risk factors for thrombotic recurrences. PATIENTS: A multi-centre observational study was performed by enrolling 177 patients with vascular APS (primary APS in 99 subjects (56%)); the median follow-up was five years (range 1-26 years). RESULTS: The observed thrombotic recurrence rate was about 7.5/100 patient years in the first five years after the first thrombotic event. While the first recurrence often occurred (45%) in patients who were not on oral anticoagulant therapy (OAT), the second recurrence mainly occurred despite ongoing OAT (80%). However, due to the real-life observational nature of this study, treatment was based on the treating physician's judgement, and no structured therapeutic protocol was applied. Moreover, compliance with OAT was not available. No differences in antiphospholipid antibodies (aPL) profile were observed between patients with or without thrombotic recurrences, but a high risk aPL profile (Miyakis type 1 and 2a) was present in 96% of our patients, 26% of whom had triple positivity. Diabetes (p < 0.01, OR 10), inherited thrombophilia (p < 0.0078, OR 4) and OAT withdrawal were independent risk factors for recurrences. CONCLUSIONS: With the limit of a real-life observational cohort study, the thrombotic recurrence rate in APS was as high as 7.5/100 patient years in the first five years after the first thrombotic event. OAT discontinuation, diabetes and inherited thrombophilia, when associated with a high-risk aPL profile, are risk factors for thrombotic recurrences.


Assuntos
Síndrome Antifosfolipídica/epidemiologia , Trombose/epidemiologia , Administração Oral , Adolescente , Adulto , Idoso , Anticorpos Antifosfolipídeos/sangue , Anticoagulantes/administração & dosagem , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/diagnóstico , Síndrome Antifosfolipídica/tratamento farmacológico , Biomarcadores/sangue , Complicações do Diabetes/etiologia , Feminino , Humanos , Incidência , Itália/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Recidiva , Medição de Risco , Fatores de Risco , Trombofilia/complicações , Trombose/diagnóstico , Trombose/prevenção & controle , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
5.
Phys Rev Lett ; 115(1): 015503, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26182106

RESUMO

A bent lithium niobate strip was exposed to a 400-GeV/c proton beam at the external lines of CERN Super Proton Synchrotron to probe its capabilities versus coherent interactions of the particles with the crystal such as channeling and volume reflection. Lithium niobate (LiNbO3) exhibits an interplanar electric field comparable to that of Silicon (Si) and remarkable piezoelectric properties, which could be exploited for the realization of piezo-actuated devices for the control of high-energy particle beams. In contrast to Si and germanium (Ge), LiNbO3 shows an intriguing effect; in spite of a low channeling efficiency (3%), the volume reflection maintains a high deflection efficiency (83%). Such discrepancy was ascribed to the high concentration (10(4) per cm2) of dislocations in our sample, which was obtained from a commercial wafer. Indeed, it has been theoretically shown that a channeling efficiency comparable with that of Si or Ge would be attained with a crystal at low defect concentration (less than ten per cm2). To better understand the role of dislocations on volume reflection, we have worked out computer simulation via dynecharm++ Monte Carlo code to study the effect of dislocations on volume reflection. The results of the simulations agree with experimental records, demonstrating that volume reflection is more robust than channeling in the presence of dislocations.

7.
Lupus ; 21(7): 806-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22635240

RESUMO

We report the experience from the Antiphospholipid Antibodies (aPL) Regional Consortium in northwest Italy, meant to support clinical research and foster collaboration among health professionals regarding the diagnosis and management of antiphospholipid syndrome (APS) patients. This cohort-study (APS Piedmont Cohort) was designed to register the clinical characteristics at inception and associated immunological manifestations at diagnosis (if any) of patients who strictly fulfilled the current criteria for APS, all recruited at the Piedmont and Valle d'Aosta regions. Clinical and laboratory data from 217 APS patients (171 with vascular events, 33 with pregnancy morbidity and 13 with both), from 16 centres within the geographical area were collected. Venous thrombosis was recorded in 45.6% of patients, arterial thrombosis in 35%, small-vessel thrombosis in 1.12% and mixed arterial and venous thrombosis in the remaining 19.4% of the cases. Pregnancy morbidity included 19 patients with unexplained fetal death beyond the 10th week of pregnancy, 17 with premature birth before the 34th week and 10 with three or more unexplained spontaneous abortions before the 10th week of gestation. This consortium represents an instrument by which to audit clinical practice, to provide counselling to local centres and to sustain future basic and clinical APS research.


Assuntos
Síndrome Antifosfolipídica/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome Antifosfolipídica/imunologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/epidemiologia , Fatores de Risco , Trombose/epidemiologia , Adulto Jovem
8.
Lupus ; 21(7): 799-801, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22635238

RESUMO

Laboratory tests for anticardiolipin antibodies (aCL) and anti-ß2glycoprotein I antibodies (a-ß2GPI) face problems common to many autoantibody assays: the lack of a reference standard and the need for each laboratory to assess assay-specific cut-off values. The aims of the study were to evaluate the reference range upper limits (99th percentile) used for aCL and a-ß2GPI in the northwest of Italy and to investigate the analytical performances of these assays with the newly obtained reference ranges. We assayed aCL and a-ß2GPI in 104 serum samples from patients without a history of thrombosis, pregnancy morbidity, tumours, infections and/or autoimmune diseases (30 males and 74 non-pregnant females). We tested all the commercial assays available in our regions (i.e. Orgentec Diagnostika, Aesku Diagnostics and Inova Diagnostics ELISA; CliA Zenit-RA and EliA Phadia Laboratory Systems). A further 30 serum samples, including 10 from healthy subjects, 10 from antiphospholipid syndrome (APS) patients and 10 from septic patients were assessed to investigate the analytical performance of the obtained cut-off limits. Reference range upper limits obtained with the commercial kits differ among assays and from the values reported by the manufacturer. Moreover, normal reference ranges calculated for IgG and IgM aCL differed from the arbitrary selected laboratory classification values suggested in the guidelines of 40 GPL and MPL.


Assuntos
Anticorpos Anticardiolipina/sangue , beta 2-Glicoproteína I/imunologia , Adulto , Idoso , Autoanticorpos/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Itália , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
9.
Rev Sci Instrum ; 92(5): 054504, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243263

RESUMO

In the last few decades, much effort has been made for the production of squeezed vacuum states in order to reduce quantum noise in the audio-frequency band. This technique has been implemented in all running gravitational-wave interferometric detectors and helped to improve their sensitivity. While the detectors are acquiring data for astrophysical observations, they must be kept in the operating condition, also called "science mode," that is, a state that requires the highest possible duty-cycle for all the instrumental parts and controls. We report the development of a highly automated setup for the generation of optical squeezed states, where all the required control loops are supervised by a software based on finite state machines; we took special care to grant ease of use, stability of operation, and possibility of auto-recovery. Moreover, the setup has been designed to be compatible with the existing software and hardware infrastructure of the Virgo detector. In this paper, we discuss the optical properties of this squeezing setup, the locking techniques, and the automation algorithms.

10.
J Phys Condens Matter ; 31(6): 065701, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30524011

RESUMO

Transient absorption and photoluminescence are experimentally investigated in the polaronic reference system lithium niobate, LiNbO[Formula: see text] (LN), with the aim to refine the microscopic model of small polaron dynamics in materials with strong electron-phonon coupling. As a unique feature, our study is performed by using two different spectroscopic methods, in crystals with dopants enhancing photorefraction or damage resistance, and over a broad temperature range from 15-400 K. Although being self-consistent for particular experimental conditions, the hitherto used microscopic polaronic models reveal inconsistencies when applied to this larger data set. We show that comprehensive modeling is unlocked by the inclusion of an additional type of polaronic state with the following characteristics: (i) strongly temperature- and dopant-dependent relaxation times, (ii) an absorption feature in the blue-green spectral range, and (iii) a Kohlrausch-Williams-Watts decay shape with a temperature-dependent stretching factor [Formula: see text] showing a behavior contrary to that of small, strong-coupling polarons. The hypothesis of self-trapped excitons (STEs, i.e. bound electron-hole pairs strongly coupled to Nb[Formula: see text] and O[Formula: see text] within a niobium-oxygen octahedron) and their pinning on defects as the microscopic origin of these characteristics is supported by a spectroscopic linkage of photoluminescence at low (15 K) and elevated (300 K) temperatures and explains the long-lifetime components in transient absorption as due to pinned STEs.

11.
ACS Appl Mater Interfaces ; 10(40): 34781-34791, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30211532

RESUMO

Future space missions will operate in increasingly hostile environments, such as those in low-perihelion solar orbits and Jovian magnetosphere. This exploration involves the selection of optical materials and components resistant to the environmental agents. The conditions in space are reproduced on ground through the use of ion accelerators. The effects of He particles coming from the solar wind impinging on a gold thin film have been systematically investigated, considering absorbed doses compatible with the duration of the European Space Agency Solar Orbiter mission. Structural and morphological changes have been proved to be dependent not only on the dose but also on the irradiation flux. A predictive model of the variation of thin film reflectance has been developed for the case of lower flux irradiation. The results are discussed regarding reliability and limitations of laboratory testing. The outcomes are important to address the procedures for the space qualification tests of optical coatings.

12.
G Ital Nefrol ; 24(2): 111-20, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-17458826

RESUMO

The diagnosis of antiphospholipid syndrome (APS) relies on clinical and laboratory criteria, which have been recently outlined in specific consensus conferences. Renal involvement in APS is not infrequent and includes different clinical patterns. For clinical purposes a distinction can be made between large vessel and microvascular involvement. Renal artery stenosis is frequent in APS. In case of microvascular involvement with an acute clinical course a differential diagnosis with other thrombotic microangiopathic diseases has to be made, taking in account thrombotic thrombocytopenic purpura, hemolytic uremic syndrome, malignant hypertension, drug nephrotoxicity (cyclosporin) and others. The disease is often chronic, with hypertension, different degrees of renal insufficiency and mild proteinuria. In patients with systemic lupus erythematosus and antiphospholipid antibodies the prognosis of kidney disease is generally poorer than in lupus alone. Finally, the kidney is almost invariably a target in catastrophic antiphospholipid syndrome. Anticoagulation is the therapy of choice, especially in arterial stenosis and acute disease, but is probably also indicated in chronic and subacute patterns. The role of immunomodulatory therapy has to be assessed.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/complicações , Fatores Imunológicos/sangue , Nefropatias/imunologia , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/imunologia , Diagnóstico Diferencial , Quimioterapia Combinada , Humanos , Hipertensão/imunologia , Imunossupressores/uso terapêutico , Nefropatias/diagnóstico , Nefropatias/tratamento farmacológico , Obstrução da Artéria Renal/imunologia
13.
Int J Cardiol ; 240: 72-77, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28385357

RESUMO

BACKGROUND: Young adults with acute myocardial infarction are a critical group to examine for the purpose of risk factor stratification and modification. In this study we aimed to assess the clinical utility of the adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) for the risk stratification of acute myocardial infarction in a cohort of young patients with antiphospholipid syndrome (APS). METHODS: The analysis included 83 consecutive APS patients (≤50years old) who presented with arterial or venous thromboembolic events. Data on cardiovascular risk factors and antiphospholipid antibodies (aPL) positivity were retrospectively collected. The aGAPSS was calculated by adding the points corresponding to the risk factors, based on a linear transformation derived from the ß-regression coefficient as follows: 3 for hyperlipidaemia, 1 for arterial hypertension, 5 for aCL IgG/IgM, 4 for anti-b2 glycoprotein I IgG/IgM and 4 for LA. RESULTS: Higher aGAPSS values were observed in patients with acute myocardial infarction when compared to the others [mean aGAPSS 11.9 (S.D. 4.15, range 4-18) Vs. mean aGAPSS 9.2 (S.D. 5.1, range 1-17); T test: p<0.05]. Significantly higher aGAPSS values were also seen in patients with acute coronary syndrome compared to patients with a history of peripheral or cerebrovascular arterial thrombotic events [mean aGAPSS 11.9 (S.D. 4.15, range 4-18) Vs. mean aGAPSS 6.7 (S.D. 5.7, range 1-17); T test: P<0.005]. CONCLUSIONS: The aGAPSS is based upon a quantitative score and could aid risk stratifying APS patients younger than 50years for the likelihood of developing coronary thrombotic events and may guide pharmacological treatment for high-risk patients.


Assuntos
Síndrome Antifosfolipídica/diagnóstico , Síndrome Antifosfolipídica/epidemiologia , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Adulto , Síndrome Antifosfolipídica/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Estudos Retrospectivos , Medição de Risco , Adulto Jovem
16.
Diabetes ; 43(3): 426-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8314015

RESUMO

Microalbuminuria is associated with an increased risk of cardiovascular disease (CVD) in insulin-dependent diabetes mellitus (IDDM) patients, but the pathophysiological basis of this association is not clear. To see whether or not hemostatic dysfunctions might contribute to explain this association, we measured tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), factor VII activity, plasma fibrinogen, and plasma endothelin-1 (ET-1) in 13 microalbuminuric (albumin excretion rate [AER], 20-200 micrograms/min) and in 13 comparable normoalbuminuric (< 20 micrograms/min) IDDM patients. t-PA and ET-1 were similar in the two groups, whereas PAI-1 activity (5.65 +/- 1.92 vs. 0.85 +/- 0.58 IU/ml, P < 0.05), factor VII (87.85 +/- 4.94 vs. 76.54 +/- 2.31%, P < 0.05), and plasma fibrinogen (3.38 +/- 0.21 vs. 2.65 +/- 0.13 g/l, P < 0.05) were significantly higher in microalbuminuric than in normoalbuminuric patients. Plasma fibrinogen was related to AER (r2 = 0.23, P < 0.05), whereas triglycerides and factor VII were related to PAI-1 (r2 = 0.39, P < 0.001 and r2 = 0.10, P < 0.05). These results suggest that microalbuminuria is associated with a hypercoagulative and hypofibrinolytic state. Hemostatic dysfunctions might be a pathogenetic link between microalbuminuria and CVD.


Assuntos
Albuminúria/sangue , Diabetes Mellitus Tipo 1/sangue , Fator VII/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Adulto , Endotelinas/sangue , Feminino , Fibrinogênio/metabolismo , Humanos , Masculino , Análise de Regressão , Ativador de Plasminogênio Tecidual/metabolismo
17.
Diabetes Care ; 20(3): 424-5, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9051398

RESUMO

OBJECTIVE: To compare activated protein C (aPC) sensitivity in 37 type I diabetic patients and 33 healthy control subjects. RESEARCH DESIGN AND METHODS: In this study, 37 type I diabetic patients and 33 healthy control subjects without personal or familial history of venous thrombosis and coagulation disorders, infections, intercurrent conditions, serum lupus anticoagulant, clinical cardiovascular complications, or drugs were examined. RESULTS: The aPC ratio (aPTT [activated partial thromboplastin time] with and without aPC) was significantly lower in the type I diabetic patients than in the control subjects (P = 0.005). CONCLUSIONS: These results suggest that the final steps of the protein C/S inhibiting system could be abnormal in type I diabetes.


Assuntos
Anticoagulantes/farmacologia , Diabetes Mellitus Tipo 1/sangue , Proteína C/farmacologia , Adulto , Diabetes Mellitus Tipo 1/fisiopatologia , Jejum , Feminino , Humanos , Masculino , Tempo de Tromboplastina Parcial , Seleção de Pacientes , Valores de Referência , Sensibilidade e Especificidade
18.
J Thromb Haemost ; 1(8): 1730-3, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12911585

RESUMO

BACKGROUND: A prolonged treatment with oral anticoagulants has been claimed to reduce the incidence of newly diagnosed cancer in the long-term follow-up of patients with venous thromboembolism. OBJECTIVES: In a multicenter prospective study we assessed the incidence of newly diagnosed clinically overt cancer in patients with a first episode of idiopathic venous thromboembolism (VTE) treated with oral anticoagulants for 3 months or 1 year. PATIENTS AND METHODS: Consecutive patients with an idiopathic venous thromboembolism who had completed 3 months of oral anticoagulant therapy without having a recurrence, bleeding or newly diagnosed cancer were randomized to discontinue oral anticoagulant therapy or to continue it for nine additional months. Idiopathic venous thromboembolism was defined as thrombosis occurring in the absence of known cancer, known thrombophilia, or temporary risk factors for venous thromboembolism. All patients were followed up for at least 1 year after randomization. RESULTS: A total of 429 patients, 265 patients with DVT and 164 with PE, were followed up for an average of 43.7 months after randomization. A newly diagnosed cancer occurred in 32 patients (7.5%), 13 (6.2%) of the 210 patients treated for 3 months and 19 (8.7%) of the 219 patients treated for 1 year (RR = 0.71, 95% confidence interval 0.36-1.41). CONCLUSIONS: The incidence of newly diagnosed clinically overt cancer is not reduced in patients with idiopathic venous thromboembolism treated with 1-year anticoagulant treatment compared with patients treated for 3 months.


Assuntos
Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Neoplasias/etiologia , Embolia Pulmonar/tratamento farmacológico , Tromboembolia/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Neoplasias/induzido quimicamente , Embolia Pulmonar/complicações , Risco , Tromboembolia/complicações , Fatores de Tempo , Resultado do Tratamento
19.
Thromb Haemost ; 58(4): 1012-6, 1987 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-2832962

RESUMO

The biochemistry and functionality of platelets from two related subjects (mother and son) with alpha-2-adrenoceptor-deficient platelets has been evaluated. Radioligand binding experiments with the specific alpha-2-adrenergic-receptor antagonist, 3H-yohimbine, showed a drastic reduction of alpha-2-adrenoceptors in platelets from both subjects in comparison with the control values. Electron microscopy studies revealed a normal morphology and a normal number of alpha granules and dense bodies. Levels of adenine nucleotides; 5-hydroxytryptamine; B-thromboglobulin; platelet-factor-4 and thromboxane A2 production were within normal limits. Platelet aggregation and 5-hydroxytryptamine production in response to adrenalin (at concentrations up to 50 microM) were absent, whereas ADP, AA, PAF, collagen and thrombin-induced aggregation, secretion, Ca++ flux and thromboxane A2 production were normal. The inhibitory effect caused by different concentrations of prostacyclin on Ca++ flux, aggregation, secretion and thromboxane A2 production of platelet functionally lacking of alpha-2-adrenoceptor was not distinguishable from control platelets and platelets preincubated with yohimbine.


Assuntos
Transtornos Plaquetários/congênito , Plaquetas/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Adulto , Transtornos Plaquetários/sangue , Transtornos Plaquetários/genética , Plaquetas/efeitos dos fármacos , Cálcio/sangue , Criança , Epinefrina/farmacologia , Epoprostenol/farmacologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Ioimbina/farmacologia
20.
Leuk Res ; 20(10): 867-76, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8960111

RESUMO

An in vitro synergism between different inducers of AML cell differentiation has been previously observed. Therefore, we treated 53 myelodysplastic (MDS) patients with a low dose combination of cis-retinoic acid (cRA, 20-40 mg/day) and 1,25 alpha (OH)2 cholecalciferol [(OH)2D3, 1-1.5 micrograms/day] +/- intermittent 6-thioguanine (30 mg/m2/day). The latter was reserved for patients with bone marrow (BM) blast excess (> or = 5%). The treatment was well tolerated, without major toxicity. Among 25 patients with BM blasts less than 5%, we observed one complete, eight partial and four minor responses (response rate 52%) with a median response duration of 8 months (2 +/- 24). Median survival, which did not correlate with response, is projected at 76 months. Thirty-one patients with BM blast excess (> or = 5%), including three of the previous group who progressed to refractory anemia with excess of blasts (RAEB), were treated with the three-drug protocol. One complete, 12 partial and six minor responses were obtained (response rate 61%) with a median response duration of 6 months (2-29+). A significant difference in survival (P < 0.005) was observed between the 19 responders (median 25 months) and the 12 non-responders (median 9 months). A reduction in the transfusion need was observed in 41% of the transfusion-dependent patients with blast excess and in 53% of those without blast excess. Therefore, combined differentiating therapy seems more effective than previously reported single agent treatments and should be considered for a larger randomized study to assess its actual impact on survival of MDS patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Crise Blástica , Transfusão de Sangue , Transplante de Medula Óssea , Colecalciferol/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue , Indução de Remissão , Análise de Sobrevida , Tioguanina/administração & dosagem , Tretinoína/administração & dosagem
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