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1.
Nucleus (La Habana) ; (63): 25-29, Jan.-June 2018. graf
Artigo em Inglês | LILACS | ID: biblio-990203

RESUMO

Abstract Heavy-ion induced two-neutron transfer reactions (18O,16O) at 84 MeV were studied on several targets up to high excitation energy of the residual nucleus thanks to the use of the MAGNEX magnetic spectrometer to detect the ejectiles. The obtained results indicate of the important role played by the nuclear paring.


Resumen Se estudiaron reacciones de transferencia de dos neutrones inducidas por iones pesados (18O, 16O) a 84 MeV en varios blancos hasta una alta energía de excitación del núcleo residual gracias al uso del espectrómetro magnético MAGNEX para detectar los residuos eyectados. Los resultados obtenidos indican el importante papel desempeñado por el apareamiento nuclear.

2.
Nucleus (La Habana) ; (63): 45-47, Jan.-June 2018.
Artigo em Inglês | LILACS | ID: biblio-990208

RESUMO

Abstract NUMEN proposes cross sections measurements of Heavy-Ion double charge exchange reactions as an innovative tool to access the nuclear matrix elements, entering the expression of the life time of Neutrinoless double beta decay (0νββ). A key aspect of the projectis the use at INFN-Laboratori Nazionali del Sud (LNS) of the Superconducting Cyclotron (CS) for the acceleration of the required high resolution and low emittance heavy-ion beams and of MAGNEX large acceptance magnetic spectrometer for the detection of the ejectiles. The experimental measurements of double charge exchange reactions induced by heavy ions present a number of challenging aspects, since such reactions are characterized by very low cross sections. First experimental results give encouraging indication on the capability to access quantitative information towards the determination of the Nuclear Matrix Elements for 0νββ decay.


Resumen NUMEN propone mediciones de secciones eficaces de reacciones de intercambio de carga doble de iones pesados como una herramienta innovadora para acceder a los elementos de la matriz nuclear, entrando en la expresión del tiempo de vida de la desintegración beta doble sin neutrino (0νββ). Un aspecto clave del proyecto es el uso en INFN-Laboratori Nazionali del Sud (LNS) del ciclotrón superconductor (CS) para la aceleración de los haces de iones pesados de alta resolución y baja emitancia requeridos y del espectrómetro magnético de gran aceptación MAGNEX para la detección de los residuos eyectados. Las mediciones experimentales de reacciones de intercambio de carga doble inducidas por iones pesados presentan una serie de aspectos desafiantes, ya que tales reacciones se caracterizan por secciones eficaces muy bajas. Los primeros resultados experimentales dan una indicación alentadora sobre la capacidad de acceder a información cuantitativa para la determinación de los Elementos de la Matriz Nuclear para la descomposición de 0νββ.

3.
Phys Rev Lett ; 119(13): 132501, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-29341708

RESUMO

The decay path of the Hoyle state in ^{12}C (E_{x}=7.654 MeV) has been studied with the ^{14}N(d,α_{2})^{12}C(7.654) reaction induced at 10.5 MeV. High resolution invariant mass spectroscopy techniques have allowed us to unambiguously disentangle direct and sequential decays of the state passing through the ground state of ^{8}Be. Thanks to the almost total absence of background and the attained resolution, a fully sequential decay contribution to the width of the state has been observed. The direct decay width is negligible, with an upper limit of 0.043% (95% C.L.). The precision of this result is about a factor 5 higher than previous studies. This has significant implications on nuclear structure, as it provides constraints to 3α cluster model calculations, where higher precision limits are needed.

5.
Haematologica ; 83(3): 217-21, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9573675

RESUMO

BACKGROUND AND OBJECTIVE: Aim of the study was to assess the efficacy of VEMB, a short-lasting therapeutic regimen (50 days) which alternates two myelotoxic drugs (cyclophosphamide and mitoxantrone) every week with two less hematologically toxic drugs (vincristine and bleomycin) in the treatment of aggressive NHL in the elderly (over 70). DESIGN AND METHODS: Between November 1994 and March 1996, 37 patients aged more than 70 years, with highly or moderately malignant NHL (according to the Working Formulation) have been enrolled into the study. The stage of the disease ranged between II and IV according to Ann Arbor. Mean age was 77 years; 14 patients (38%) had stage IV; 19 patients (51%) had LDH higher than normal; 26 patients (70%) had extranodal and 9 patients (24%) had bulky disease at time of diagnosis. RESULTS: Sixty-two percent of patients achieved a complete and 22% a partial remission. Non-responders amounted to 5%. Four patients (11%) died during the therapy. Nine patients (24%) experienced grade III-IV neutropenia. The most frequently observed event was mild neurotoxicity (43% of cases). The overall survival rate at 30 months was 55%. DFS at 24 months was 66%. INTERPRETATION AND CONCLUSIONS: VEMB is a therapeutic regimen whose efficacy is comparable to that of the other derived MACOP-B therapeutic regimens used in the elderly NHL. It has proved to have a good feasibility, though the number of toxic deaths should not be neglected.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma não Hodgkin/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Bleomicina/administração & dosagem , Bleomicina/uso terapêutico , Bleomicina/toxicidade , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Ciclofosfamida/toxicidade , Esquema de Medicação , Feminino , Humanos , Itália , Linfoma não Hodgkin/classificação , Linfoma não Hodgkin/mortalidade , Masculino , Mitoxantrona/administração & dosagem , Mitoxantrona/uso terapêutico , Mitoxantrona/toxicidade , Taxa de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem , Vincristina/uso terapêutico , Vincristina/toxicidade
6.
Minerva Endocrinol ; 19(4): 163-8, 1994 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-7739469

RESUMO

The effects of two different concentrations of IL-2 on human pituitary adenomas (one secreting ACTH and one secreting GH) were evaluated in vitro. A specimen of the tumor was dissagregated and the cells were incubated for three days with RPMI 1640 medium. The medium was then decanted and the cells were incubated with 1 mlo of fresh medium for three hours and then with new fresh medium containing two different concentrations of IL-2, 100U/ml, for three hours too. The pituitary hormones, ACTH and GH, released into the medium were assayed by RIA. Dose of 100 U IL-2 induced a profound increase of ACTH release. The other dose decreased ACTH release. The release of GH was suppressed by IL-2 at the two concentrations tested. IL-2 may be an immunologic messenger exerting direct action at pituitary level. It appears probable that IL-2 plays an important role in determining the response of the pituitary to stress and infections.


Assuntos
Adenoma/metabolismo , Hormônio Adrenocorticotrópico/biossíntese , Hormônio do Crescimento/biossíntese , Interleucina-2/farmacologia , Neoplasias Hipofisárias/metabolismo , Adenoma/patologia , Relação Dose-Resposta a Droga , Humanos , Neoplasias Hipofisárias/patologia , Células Tumorais Cultivadas
8.
Pathologica ; 86(1): 66-9, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8072805

RESUMO

We treated 13 Hairy Cell Leukemia patients with rIFN a 2b. In case of complete/partial response, the patients were submitted to maintenance treatment, while, in case of minimal/no response, a second induction cycle was administered, followed by a maintenance one. The patients were followed, on an outpatients basis, for 18 months at least, obtaining a 100% overall response rate; one patient had complete response, 7 had partial response, and 5 only minimal response. Six patients (46%) relapsed an average of 13 months after the end of the treatment. The utility of a maintenance therapy is discussed.


Assuntos
Interferon-alfa/uso terapêutico , Leucemia de Células Pilosas/terapia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes
9.
Minerva Endocrinol ; 18(2): 77-81, 1993 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-8289753

RESUMO

Sixty cases of goitrous Hashimoto's thyroiditis were observed at the first diagnosis. For 18 of the cases, the diagnosis was made only on the basis of cytological examination since antithyroid antibodies were always negative. To determine if seronegative or seropositive forms constituted a particular genetically determined subgroup, we evaluated whether such peculiarities were related to specific HLA haplotype. Analysis of HLA antigens showed in the seropositive a significant increase in the frequency of HLA-B51 and HLA-A2, a significant decrease in the frequency of HLA-A1 and HLA-DR1. In seronegative cases no increase was found in the frequency of HLA-A-B-DR antigens, but they showed a strong positive association with HLA-DQ3. Our results show that association of Hashimoto's thyroiditis with HLA antigens was different in seronegative and seropositive subgroup. This finding would seem to support the hypothesis that in a few subjects the entire immune process develops exclusively within the involved organ and this process would be genetically determined.


Assuntos
Antígenos HLA/genética , Tireoidite Autoimune/genética , Tireoidite Autoimune/imunologia , População Branca/genética , Adulto , Feminino , Haplótipos/imunologia , Humanos , Masculino , Pessoa de Meia-Idade
11.
Ann N Y Acad Sci ; 534: 584-96, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3133972

RESUMO

Beta-carotene (BC) and canthaxanthine (CX), two carotenoids with and without pro-vitamin A activity, respectively, were found to help to prevent benzo[a]pyrene (BP)-induced skin carcinogenesis in the dark and BP photocarcinogenesis (UV 300-400 nm) when given as an oral supplement to female Swiss albino mice. The same experimental procedure was adapted to 8-methoxypsoralen (8-MOP) photoinduction of mammary carcinomas in mice. Here also, the two carotenoids were strongly antitumorigenic. Indeed, 8-MOP photomutagenesis, tested in S. typhimurium TA 102, appeared to depend on a two-step reaction, namely an oxygen-independent DNA-8-MOP photoadduct, followed by an oxygen-dependent second step, sensitive to carotenoids. This result suggests that dietary carotenoids (powerful antioxidant molecules) might prevent the carcinogenic risk caused by substances that are transformed into ultimate carcinogens by oxidative processes which are indirectly carcinogenic. Finally, to verify whether supplemental carotenoids can affect carcinogenesis where neither light excitation nor oxidative metabolic processes are involved, an experimental attempt was made on gastric carcinogenesis induced in rats by the direct carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The results demonstrate that supplemental carotenoids do not affect initiation and progression stages, but do prevent the progression stage of dysplasias to infiltrating gastric carcinomas. Thus, this provides strong presumptive evidence for oxygen radical involvement in the later stages of this neoplastic development, as recently reported in the literature. As far as mutagenicity in S. typhimurium is concerned, carotenoids do not exert, as expected, any protective effect on MNNG mutagenic activity. The above experimental data suggest that supplemental carotenoids, instead of sunscreen preparations, can be adopted by outdoor workers to prevent skin cancer. Accordingly, such natural antioxidants may be useful in human chemoprevention against neoplasias of the lung, breast, urinary bladder, and colon and rectum even after radical surgery.


Assuntos
Carcinógenos , Carotenoides/uso terapêutico , Neoplasias Experimentais/prevenção & controle , Animais , Benzo(a)pireno , Cantaxantina , Carotenoides/análogos & derivados , Dieta , Feminino , Radicais Livres , Metoxaleno , Metilnitronitrosoguanidina , Camundongos , Testes de Mutagenicidade , Neoplasias Experimentais/induzido quimicamente , Terapia PUVA , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/prevenção & controle , beta Caroteno
15.
Minerva Med ; 70(8): 595-603, 1979 Feb 18.
Artigo em Italiano | MEDLINE | ID: mdl-372858

RESUMO

A controlled clinical trial was made of the anti-ammoniaemic properties of gamma-ethylester glutamic acid, arginine and placebo in a series of 45 patients with hepatic insufficiency characterized by hyperammonemia (excluding cases of pre-coma and coma) randomly assigned to three groups for treatment with: gamma-ethylester of glutamic acid (25 g), l-arginine (25 g) and physiological solution in identical 500 ml bottles. Various parameters were controlled. The results obtained were assessed with different statistical techniques, depending on the parameter concerned and the aims of the trial. Blood ammoniaemia was significantly decreased by both-ethylester of glutamic acid and arginine though the former was more effective quantitatively and in terms of time. SGOT and BSF values also followed the same pattern.


Assuntos
Amônia/sangue , Glutamatos/uso terapêutico , Encefalopatia Hepática/tratamento farmacológico , Gasometria , Ensaios Clínicos como Assunto , Avaliação de Medicamentos , Glutamatos/farmacologia , Humanos , Testes de Função Hepática , Tempo de Protrombina , Transaminases/sangue
16.
Minerva Med ; 69(54): 3705-13, 1978 Nov 10.
Artigo em Italiano | MEDLINE | ID: mdl-733052

RESUMO

A rare case of cystic lymphangioma of the spleen accompanying hypersplenism syndrome is described. After stressing the importance of certain examinations such as arteriography and splenic scintigraphy in diagnosis the condition, the many ways in which cystic lymphangioma of the spleen may present clinically are reviewed; these go from asymptomatic to straightforward splenomegaly, with or without clinical signs, up to a clear-cut hypersplenism syndrome. The present case merits consideration for three reasons: 1) The absolutely exceptional nature of cystic lymphangioma of the spleen; 2) Exceptional association with hypersplenism syndrome; 3) Remission of the syndrome following splenectomy. It is concluded that, notwithstanding the condition's rarity, cystic lymphangioma of the spleen should be considered in the differential diagnosis of splenomegalic syndromes when these are also accompanied by hypersplenism.


Assuntos
Hiperesplenismo/etiologia , Linfangioma/complicações , Neoplasias Esplênicas/complicações , Adulto , Feminino , Humanos , Linfangioma/patologia , Baço/patologia , Esplenectomia , Neoplasias Esplênicas/patologia , Esplenomegalia/etiologia
17.
Minerva Med ; 69(25): 1739-43, 1978 May 19.
Artigo em Italiano | MEDLINE | ID: mdl-662176

RESUMO

The ethiocholanolone test was used to evaluate the granulocyte reserve in 22 patients with Hodgkin's disease before and during polychemical antiblastic and radiation therapy. Under basal conditions, the reserve was normal and its behavior was fairly constantly related to histological type. Stress is laid on the inadequacy of the simple leukocyte count as a guide to the planning of treatment by comparison with the more accurate picture offered by the granulocyte reserve.


Assuntos
Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Granulócitos , Doença de Hodgkin/patologia , Contagem de Leucócitos , Leucócitos , Adolescente , Adulto , Quimioterapia Combinada , Etiocolanolona , Feminino , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Humanos , Depleção Linfocítica , Masculino , Pessoa de Meia-Idade
18.
Minerva Med ; 69(20): 1367-74, 1978 Apr 28.
Artigo em Italiano | MEDLINE | ID: mdl-566393

RESUMO

The AA. administered i.v. large doses of gamma-ethylester of glutamic acid to 22 patients affected with severe liver failure associated to mental and neuromuscolar abnormalities as tremors, confusion, restlesness which have been duly recorded for the purpose of this evaluation. The average daily dose was 36.3 gm and the treatment lasted as an average 9.5 days. The peripheral venous blood ammonia was checked, at the beginning and at the end of the treatment, in all the patients and in some, at random, the following parameters were determined: pH, pCO2, pO2, HCO3, TCO2, oxygen saturation on arterial blood. The treatment caused a statistically remarkable decrease of blood ammonia in 21 of 22 patients. The mental and neuromuscolar abnormalities too showed a statistically important downward trend vs. the basal values. The acid-base balance did not record any remarkable variation. The AA. judge as absolutely positive the trial carried out with gamma-ethylester of glutamic acid. The large doses used caused clear-cut and dramatic improvements and were estremely well tolerated.


Assuntos
Amônia/sangue , Glutamatos/uso terapêutico , Encefalopatia Hepática/tratamento farmacológico , Desequilíbrio Ácido-Base/etiologia , Glutamatos/administração & dosagem , Encefalopatia Hepática/complicações , Humanos , Injeções Intravenosas , Cirrose Hepática/complicações , Transtornos Mentais/etiologia
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