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1.
Phys Rev Lett ; 131(22): 222501, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38101385

RESUMEN

We report on the results obtained with the global CUPID-0 background model, which combines the data collected in the two measurement campaigns for a total exposure of 8.82 kg×yr of ^{82}Se. We identify with improved precision the background sources within the 3 MeV energy region, where neutrinoless double ß decay of ^{82}Se and ^{100}Mo is expected, making more solid the foundations for the background budget of the next-generation CUPID experiment. Relying on the excellent data reconstruction, we measure the two-neutrino double ß-decay half-life of ^{82}Se with unprecedented accuracy: T_{1/2}^{2ν}=[8.69±0.05(stat)_{-0.06}^{+0.09}(syst)]×10^{19} yr.

2.
Phys Rev Lett ; 129(11): 111801, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36154394

RESUMEN

CUPID-0, an array of Zn^{82}Se cryogenic calorimeters, was the first medium-scale demonstrator of the scintillating bolometers' technology. The first project phase (March 2017-December 2018) allowed the most stringent limit on the neutrinoless double beta decay half-life of the isotope of interest, ^{82}Se, to be set. After a six month long detector upgrade, CUPID-0 began its second and last phase (June 2019-February 2020). In this Letter, we describe the search for neutrinoless double beta decay of ^{82}Se with a total exposure (phase I+II) of 8.82 kg yr^{-1} of isotope. We set a limit on the half-life of ^{82}Se to the ground state of ^{82}Kr of T_{1/2}^{0ν}(^{82}Se)>4.6×10^{24} yr (90% credible interval), corresponding to an effective Majorana neutrino mass m_{ßß}<(263-545) meV. We also set the most stringent lower limits on the neutrinoless decays of ^{82}Se to the 0_{1}^{+}, 2_{1}^{+}, and 2_{2}^{+} excited states of ^{82}Kr, finding 1.8×10^{23} yr, 3.0×10^{23} yr, and 3.2×10^{23} yr (90% credible interval) respectively.

3.
Phys Rev Lett ; 129(25): 252701, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36608219

RESUMEN

We present an improved measurement of the carbon-nitrogen-oxygen (CNO) solar neutrino interaction rate at Earth obtained with the complete Borexino Phase-III dataset. The measured rate, R_{CNO}=6.7_{-0.8}^{+2.0} counts/(day×100 tonnes), allows us to exclude the absence of the CNO signal with about 7σ C.L. The correspondent CNO neutrino flux is 6.6_{-0.9}^{+2.0}×10^{8} cm^{-2} s^{-1}, taking into account the neutrino flavor conversion. We use the new CNO measurement to evaluate the C and N abundances in the Sun with respect to the H abundance for the first time with solar neutrinos. Our result of N_{CN}=(5.78_{-1.00}^{+1.86})×10^{-4} displays a ∼2σ tension with the "low-metallicity" spectroscopic photospheric measurements. Furthermore, our result used together with the ^{7}Be and ^{8}B solar neutrino fluxes, also measured by Borexino, permits us to disfavor at 3.1σ C.L. the "low-metallicity" standard solar model B16-AGSS09met as an alternative to the "high-metallicity" standard solar model B16-GS98.

4.
Phys Rev Lett ; 123(3): 032501, 2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31386478

RESUMEN

CUPID-0 is the first pilot experiment of CUPID, a next-generation project for the measurement of neutrinoless double beta decay (0νDBD) with scintillating bolometers. The detector, consisting of 24 enriched and 2 natural ZnSe crystals, has been taking data at Laboratori Nazionali del Gran Sasso from June 2017 to December 2018, collecting a ^{82}Se exposure of 5.29 kg×yr. In this Letter we present the phase-I results in the search for 0νDBD. We demonstrate that the technology implemented by CUPID-0 allows us to reach the lowest background for calorimetric experiments: (3.5_{-0.9}^{+1.0})×10^{-3} counts/(keV kg yr). Monitoring 3.88×10^{25} ^{82}Se nuclei×yr we reach a 90% credible interval median sensitivity of T_{1/2}^{0ν}>5.0×10^{24} yr and set the most stringent limit on the half-life of ^{82}Se 0νDBD: T_{1/2}^{0ν}>3.5×10^{24} yr (90% credible interval), corresponding to m_{ßß}<(311-638) meV depending on the nuclear matrix element calculations.

5.
Phys Rev Lett ; 123(26): 262501, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31951429

RESUMEN

We report on the measurement of the two-neutrino double-ß decay of ^{82}Se performed for the first time with cryogenic calorimeters, in the framework of the CUPID-0 experiment. With an exposure of 9.95 kg yr of Zn^{82}Se, we determine the two-neutrino double-ß decay half-life of ^{82}Se with an unprecedented precision level, T_{1/2}^{2ν}=[8.60±0.03(stat) _{-0.13}^{+0.19}(syst)]×10^{19} yr. The very high signal-to-background ratio, along with the detailed reconstruction of the background sources allowed us to identify the single state dominance as the underlying mechanism of such a process, demonstrating that the higher state dominance hypothesis is disfavored at the level of 5.5σ.

6.
Phys Rev Lett ; 120(23): 232502, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29932707

RESUMEN

We report the result of the search for neutrinoless double beta decay of ^{82}Se obtained with CUPID-0, the first large array of scintillating Zn^{82}Se cryogenic calorimeters implementing particle identification. We observe no signal in a 1.83 kg yr ^{82}Se exposure, and we set the most stringent lower limit on the 0νßß ^{82}Se half-life T_{1/2}^{0ν}>2.4×10^{24} yr (90% credible interval), which corresponds to an effective Majorana neutrino mass m_{ßß}<(376-770) meV depending on the nuclear matrix element calculations. The heat-light readout provides a powerful tool for the rejection of α particles and allows us to suppress the background in the region of interest down to (3.6_{-1.4}^{+1.9})×10^{-3} counts/(keV kg yr), an unprecedented level for this technique.

7.
Eur Phys J C Part Fields ; 81(8): 722, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720725

RESUMEN

Localization and modeling of radioactive contaminations is a challenge that ultra-low background experiments are constantly facing. These are fundamental steps both to extract scientific results and to further reduce the background of the detectors. Here we present an innovative technique based on the analysis of α - α delayed coincidences in 232 Th and 238 U decay chains, developed to investigate the contaminations of the ZnSe crystals in the CUPID-0 experiment. This method allows to disentangle surface and bulk contaminations of the detectors relying on the different probability to tag delayed coincidences as function of the α decay position.

8.
Phytochemistry ; 170: 112222, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31810054

RESUMEN

Hypertension has become the leading risk factor for worldwide cardiovascular diseases. Conventional pharmacological treatment, after both dietary and lifestyle changes, is generally proposed. In this review, we present the antihypertensive properties of phytocomplexes from thirteen plants, long ago widely employed in ethnomedicines and, in recent years, increasingly evaluated for their activity in vitro and in vivo, also in humans, in comparison with synthetic drugs acting on the same systems. Here, we focus on the demonstrated or proposed mechanisms of action of such phytocomplexes and of their constituents proven to exert cardiovascular effects. Almost seventy phytochemicals are described and scientifically sound pertinent literature, published up to now, is summarized. The review emphasizes the therapeutic potential of these natural substances in the treatment of the 'high normal blood pressure' or 'stage 1 hypertension', so-named according to the most recent European and U.S. guidelines, and as a supplementation in more advanced stages of hypertension, however needing further validation by clinical trial intensification.


Asunto(s)
Antihipertensivos/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Fitoquímicos/uso terapéutico , Animales , Antihipertensivos/química , Humanos , Fitoquímicos/química
9.
Science ; 259(5097): 968-71, 1993 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-8438156

RESUMEN

One of the most frequent cytogenetic abnormalities in human leukemia and myelodysplasia is an interstitial deletion within chromosome 5q. A tumor suppressor gene has been hypothesized to lie in 5q31, the smallest commonly deleted region. IRF-1, a gene whose product manifests anti-oncogenic activity, was mapped to 5q31.1. IRF-1 lies between IL-5 and CDC25C and is centromeric to IL-3 and GM-CSF. Among these genes, only IRF-1 was consistently deleted at one or both alleles in 13 cases of leukemia or myelodysplasia with aberrations of 5q31. Inactivating rearrangements of one IRF-1 allele, accompanied by deletion of the second allele, were also identified in one case of acute leukemia. Thus, IRF-1 may be a critically deleted gene in human leukemia and myelodysplasia.


Asunto(s)
Mapeo Cromosómico , Cromosomas Humanos Par 5 , Proteínas de Unión al ADN/genética , Eliminación de Gen , Genes Supresores de Tumor , Leucemia/genética , Síndromes Mielodisplásicos/genética , Fosfoproteínas/genética , Secuencia de Bases , Southern Blotting , Sondas de ADN , Reordenamiento Génico , Humanos , Hibridación in Situ , Factor 1 Regulador del Interferón , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa
10.
Eur Phys J C Part Fields ; 78(11): 888, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30881205

RESUMEN

The CUPID-0 experiment searches for double beta decay using cryogenic calorimeters with double (heat and light) read-out. The detector, consisting of 24 ZnSe crystals 95 % enriched in 82 Se and two natural ZnSe crystals, started data-taking in 2017 at Laboratori Nazionali del Gran Sasso. We present the search for the neutrino-less double beta decay of 82 Se into the 0 1 + , 2 1 + and 2 2 + excited states of 82 Kr with an exposure of 5.74 kg · yr (2.24 × 10 25  emitters · yr). We found no evidence of the decays and set the most stringent limits on the widths of these processes: Γ ( 82 Se → 82 Kr 0 1 + )8.55 × 10 - 24  yr - 1 , Γ ( 82 Se → 82 Kr 2 1 + ) < 6.25 × 10 - 24  yr - 1 , Γ ( 82 Se → 82 Kr 2 2 + )8.25 × 10 - 24  yr - 1 (90 % credible interval).

11.
Eur Phys J C Part Fields ; 78(9): 734, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30839752

RESUMEN

The suppression of spurious events in the region of interest for neutrinoless double beta decay will play a major role in next generation experiments. The background of detectors based on the technology of cryogenic calorimeters is expected to be dominated by α particles, that could be disentangled from double beta decay signals by exploiting the difference in the emission of the scintillation light. CUPID-0, an array of enriched Zn 82 Se scintillating calorimeters, is the first large mass demonstrator of this technology. The detector started data-taking in 2017 at the Laboratori Nazionali del Gran Sasso with the aim of proving that dual read-out of light and heat allows for an efficient suppression of the α background. In this paper we describe the software tools we developed for the analysis of scintillating calorimeters and we demonstrate that this technology allows to reach an unprecedented background for cryogenic calorimeters.

12.
Eur Phys J C Part Fields ; 78(5): 428, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30996670

RESUMEN

The CUPID-0 detector hosted at the Laboratori Nazionali del Gran Sasso, Italy, is the first large array of enriched scintillating cryogenic detectors for the investigation of 82 Se neutrinoless double-beta decay ( 0 ν ß ß ). CUPID-0 aims at measuring a background index in the region of interest (RoI) for 0 ν ß ß at the level of 10 - 3  counts/(keV kg years), the lowest value ever measured using cryogenic detectors. CUPID-0 operates an array of Zn 82 Se scintillating bolometers coupled with bolometric light detectors, with a state of the art technology for background suppression and thorough protocols and procedures for the detector preparation and construction. In this paper, the different phases of the detector design and construction will be presented, from the material selection (for the absorber production) to the new and innovative detector structure. The successful construction of the detector lead to promising preliminary detector performance which is discussed here.

13.
J Clin Invest ; 89(4): 1178-88, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1348253

RESUMEN

Hemopoietic stem cells from human fetal liver were transplanted in utero into preimmune fetal sheep (48-54 days of gestation). The fate of donor cells was followed using karyotype analysis, by immunofluorescence labeling with anti-CD antibodies, and by fluorescent in situ hybridization using human-specific DNA probes. Engraftment occurred in 13 of 33 recipients. Of five live born sheep that exhibited chimerism, all expressed human cells in the marrow, whereas three expressed them in blood as well. Engraftment was multilineage (erythroid, myeloid, and lymphoid) and human hemopoietic progenitors (multipotent colony-forming units, colony-forming units-granulocyte, macrophage, and erythroid burst-forming units) capable of forming colonies in vitro were detected in all five lambs for greater than 2 yr. These progenitors responded to human-specific growth factors both in vitro and in vivo. Thus the administration of recombinant human IL-3 and granulocyte macrophage-colony-stimulating factor to chimeric sheep resulted in a 2.1-3.4-fold increase in the relative expression of donor (human) cells. These results demonstrate that the permissive environment of the preimmune fetal sheep provides suitable conditions for the engraftment and long-term multilineage expression of human hemopoietic stem cells in a large animal model. In this model, donor human cells appear to retain certain phenotypic and functional characteristics that can be used to manipulate the size of donor cell pool.


Asunto(s)
Feto/inmunología , Trasplante de Células Madre Hematopoyéticas , Trasplante Heterólogo , Animales , Antígenos CD/análisis , Medios de Cultivo , Femenino , Glicoforinas/análisis , Supervivencia de Injerto , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Células Madre Hematopoyéticas/fisiología , Humanos , Interleucina-3/farmacología , Embarazo , Proteínas Recombinantes/farmacología , Ovinos
14.
Mol Cell Biol ; 10(1): 401-4, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2403643

RESUMEN

The chromosomal locations, amounts, and level of expression of transfected, amplified c-myc and dihydrofolate reductase sequences were measured in cells cultured in the presence and absence of methotrexate. These studies show that the location and amount of transfected sequences, as well as the level of expression, were more variable when the cells were cultured in methotrexate.


Asunto(s)
Amplificación de Genes/efectos de los fármacos , Metotrexato/farmacología , Animales , Sondas de ADN , ADN Recombinante/genética , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Hibridación de Ácido Nucleico , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-myc , Proto-Oncogenes , Tetrahidrofolato Deshidrogenasa/genética , Transfección
15.
Eur J Med Chem ; 41(9): 1025-40, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16737760

RESUMEN

On the basis of the affinities at the alpha1a-, alpha1b- and alpha1d-adrenoceptors and the 5-HT1A receptor of a previous series of sixteen 2-[(2-phenoxyethyl)aminomethyl]-1,4-benzodioxanes ortho monosubstituted at the phenoxy moiety, a number of ortho disubstituted analogues were designed, synthesized in both the enantiomeric forms and tested in binding assays on the same receptors. The affinity values of the new compounds 1-11 were compared with those of the enantiomers of the 2,6-dimethoxyphenoxy analogue, the well-known alpha1 antagonist WB4101, and of the ortho monosubstituted derivatives, suggesting some distinctive aspects of the interaction of the phenoxy moiety, in particular with the alpha1a-AR and the 5-HT1A receptor, of the monosubstituted and the disubstituted compounds. A classical quantitative structure-activity relationship (Hansch) analysis was applied to the whole set of the S enantiomers of the ortho mono- and disubstituted WB4101 analogues (26 compounds), finding a very good correlation for the alpha1a affinity. For this latter, a significant parabolic relationship was also found with the volume of the two ortho substituents. Diametrically opposite, the same relationships for the 5-HT1A exhibit low or insignificant correlation coefficients.


Asunto(s)
Antagonistas Adrenérgicos/química , Antagonistas Adrenérgicos/farmacología , Antagonistas de Receptores Adrenérgicos alfa 1 , Dioxanos/antagonistas & inhibidores , Dioxanos/farmacología , Metilaminas/antagonistas & inhibidores , Metilaminas/farmacología , Relación Estructura-Actividad Cuantitativa , Animales , Células CHO , Cricetinae , Humanos , Estructura Molecular , Estereoisomerismo
16.
Cancer Res ; 42(8): 3125-31, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7093956

RESUMEN

Quantitative estimates of cytokinetic perturbations induced over a 30-hr interval in KHT tumor cells in vivo by a single dose of 1-beta-D-arabinofuranosylcytosine (ara-C) were inferred from measurements of DNA distribution sequences, tritiated thymidine incorporation into tumor cell DNA, and radioactivity of cells labeled with tritiated thymidine prior to treatment with ara-C. These data were analyzed collectively to produce a mathematical model describing the effects of ara-C on tumor cell cycle kinetics. During analysis, we postulated that ara-C produced a transient block at the a G1-S-phase boundary, that ara-C killed all cells in S phase, and that the cells killed by ara-C did not cycle after treatment. The analysis showed that the duration of the G1-S-boundary block was 5.5 hr, that cells were recruited from G0 into cycle beginning 5.5 hr posttreatment, and that the G1, S, and G2M phase durations of the clonogenic cells which were initially 2, 11.5, and 2 hr, respectively, changed to 0.8, 4.6, and 0.8 hr at 14 hr posttreatment. Cells killed by ara-C were removed from the tumor beginning 10 hr posttreatment. We then used the mathematical model to predict clonogenic tumor cell survival following a second dose of ara-C administered at time intervals ranging from 1 to 30 hr after the first treatment. Clonogenic tumor cell survival following the second dose of ara-C was then experimentally determined and agreed well with the model predictions.


Asunto(s)
Citarabina/farmacología , Sarcoma Experimental/fisiopatología , Animales , División Celular/efectos de los fármacos , Línea Celular , Replicación del ADN/efectos de los fármacos , ADN de Neoplasias/metabolismo , Citometría de Flujo , Cinética , Ratones
17.
Cancer Res ; 60(19): 5405-9, 2000 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11034080

RESUMEN

This report describes the development and validation of quantitative microsatellite analysis (QuMA) for rapid measurement of relative DNA sequence copy number. In QuMA, the copy number of a test locus relative to a pooled reference is assessed using quantitative, real-time PCR amplification of loci carrying simple sequence repeats. Use of simple sequence repeats is advantageous because of the large numbers that are mapped precisely. In addition, all markers are informative because QuMA does not require that they be polymorphic. The utility of QuMA is demonstrated in assessment of the extent of deletions of chromosome 2 in leukemias arising in radiation-sensitive inbred SJL mice and in analysis of the association of increased copy number of the putative oncogene ZNF217 with reduced survival duration in ovarian cancer patients.


Asunto(s)
ADN de Neoplasias/genética , Dosificación de Gen , Repeticiones de Microsatélite/genética , Reacción en Cadena de la Polimerasa/métodos , Animales , ADN de Neoplasias/análisis , Femenino , Genes Supresores de Tumor/genética , Humanos , Leucemia Mieloide/etiología , Leucemia Mieloide/genética , Leucemia Inducida por Radiación/genética , Masculino , Ratones , Ratones Endogámicos , Ratones Noqueados , Proteínas de Neoplasias/genética , Técnicas de Amplificación de Ácido Nucleico , Neoplasias Ováricas/genética , Pronóstico , Reproducibilidad de los Resultados , Análisis de Supervivencia , Transactivadores/genética
18.
Eur Phys J C Part Fields ; 76(7): 364, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28280442

RESUMEN

The R&D activity performed during the last years proved the potential of ZnSe scintillating bolometers to the search for neutrino-less double beta decay, motivating the realization of the first large-mass experiment based on this technology: CUPID-0. The isotopic enrichment in [Formula: see text]Se, the Zn[Formula: see text]Se crystals growth, as well as the light detectors production have been accomplished, and the experiment is now in construction at Laboratori Nazionali del Gran Sasso (Italy). In this paper we present the results obtained testing the first three Zn[Formula: see text]Se crystals operated as scintillating bolometers, and we prove that their performance in terms of energy resolution, background rejection capability and intrinsic radio-purity complies with the requirements of CUPID-0.

19.
Diabetes ; 25(7): 614-22, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-179906

RESUMEN

Supplementation of rat lymphocyte cultures with plasma from alloxan-diabetic rats produced a dose-dependent suppression of mitogen-induced blastogenic responses. Viability measurements indicated that this inhibition was not due to a direct cytotoxic effect of alloxan-diabetic plasma on rat mononuclear leukocytes in vitro. This inhibition was not explained by hyperglycemia alone and was observed when blastogenesis was induced in vitro by phytohemagglutinin (PHA), concanavalin A (con A), or allogeneic cells. Peripheral blood lymphocytes from alloxan-diabetic rats appeared to be more sensitive than normal cells to the inhibitory effect of diabetic plasma. Heating at 56 degrees for 60 minutes produced only a partial loss of the inhibition by diabetic plasma. Alloxan-diabetic rat plasma promoted an increased accumulation of adenosine 3',5'-monophosphate (cyclic AMP) in mononuclear leukocytes. Insulin (1 and 100 muU./ml.) in vitro enhanced PHA-induced blastogenesis but failed to reverse the inhibition caused by diabetic plasma. Ultrafiltration through a cellulose dialysis membrane with an exclusion size of 12,000 molecular weight did not remove the inhibitory factor(s). These results indicate that a depressed cellular immune response is produced during an insulin-deficient diabetic state. The suppressed in-vitro blastogenic response of lymphocytes from alloxan-diabetic rats appears to involve some circulating inhibitory factor(s) in diabetic plasma. This inhibition may be explained, in part, by the ability of diabetic plasma to elevate cyclic AMP in mononuclear leukocytes.


Asunto(s)
Diabetes Mellitus Experimental/sangre , Activación de Linfocitos , Animales , Suero Antilinfocítico , Sangre , Supervivencia Celular , Células Cultivadas , Concanavalina A/farmacología , AMP Cíclico/metabolismo , Pruebas Inmunológicas de Citotoxicidad , Relación Dosis-Respuesta a Droga , Calor , Hiperglucemia , Insulina/farmacología , Lectinas/farmacología , Masculino , Ratas , Timidina/metabolismo
20.
Curr Opin Biotechnol ; 3(6): 623-31, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1369118

RESUMEN

This review describes molecular cytogenetic techniques for detection and characterization of genetic aberrations associated with human disease. The techniques of fluorescence in situ hybridization, primed in situ labeling and comparative genome hybridization are described, as are probes for repeated sequences, whole chromosomes and specific loci. Also reviewed are applications of these technologies to pre- and neonatal diagnosis and to the characterization of human malignancies.


Asunto(s)
Citogenética/métodos , Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/genética , Leucemia/diagnóstico , Neoplasias/diagnóstico , Secuencia de Bases , ADN/genética , Femenino , Humanos , Recién Nacido , Leucemia/genética , Datos de Secuencia Molecular , Neoplasias/genética , Embarazo , Diagnóstico Prenatal , Pronóstico
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