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1.
Phys Rev Lett ; 131(16): 161801, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925688

RESUMO

Thermal dark matter models with particle χ masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and ordinary matter. We report on a new search for the sub-GeV χ production through the interaction mediated by a new vector boson, called the dark photon A^{'}, in collisions of 100 GeV electrons with the active target of the NA64 experiment at the CERN SPS. With 9.37×10^{11} electrons on target collected during 2016-2022 runs NA64 probes for the first time the well-motivated region of parameter space of benchmark thermal scalar and fermionic dark matter models. No evidence for dark matter production has been found. This allows us to set the most sensitive limits on the A^{'} couplings to photons for masses m_{A^{'}}≲0.35 GeV, and to exclude scalar and Majorana dark matter with the χ-A^{'} coupling α_{D}≤0.1 for masses 0.001≲m_{χ}≲0.1 GeV and 3m_{χ}≤m_{A^{'}}.

2.
Phys Rev Lett ; 129(16): 161801, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306760

RESUMO

A search for a new Z^{'} gauge boson associated with (un)broken B-L symmetry in the keV-GeV mass range is carried out for the first time using the missing-energy technique in the NA64 experiment at the CERN SPS. From the analysis of the data with 3.22×10^{11} electrons on target collected during 2016-2021 runs, no signal events were found. This allows us to derive new constraints on the Z^{'}-e coupling strength, which, for the mass range 0.3≲m_{Z^{'}}≲100 MeV, are more stringent compared to those obtained from the neutrino-electron scattering data.

3.
Artigo em Inglês | MEDLINE | ID: mdl-23157989

RESUMO

Mucosa-associated lymphoid tissue (MALT) lymphomas are known to occur in Sjögren syndrome (SS) patients, but reported cases in labial salivary glands (LSG) are rare. We report a case of 60-year-old female patient with SS who developed MALT lymphoma in the labial salivary glands during a 2-year time interval when she was participating in the Sjögren's International Clinical Collaborative Alliance, an ongoing longitudinal multisite observational study funded by the National Institutes of Health of the United States. At follow-up exam, LSG biopsy showed atypical diffuse infiltration by mononuclear cells of variable size and atypical nuclei affecting the whole specimen with destruction of glandular architecture, leading to a diagnosis of B-cell MALT lymphoma. Computerized tomography and bone marrow biopsy failed to show additional evidence of disease. Clinical, serologic, ocular, histologic and immunohistochemical findings are presented. A "watch and wait" policy was adopted with regular examinations.


Assuntos
Detecção Precoce de Câncer , Neoplasias Labiais/diagnóstico , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Neoplasias das Glândulas Salivares/diagnóstico , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/complicações , Biópsia , Medula Óssea/patologia , Feminino , Seguimentos , Humanos , Neoplasias Labiais/patologia , Linfoma de Zona Marginal Tipo Células B/patologia , Pessoa de Meia-Idade , Neoplasias das Glândulas Salivares/patologia , Tomografia Computadorizada por Raios X , Conduta Expectante
4.
Psychoneuroendocrinology ; 19(1): 55-64, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-9210212

RESUMO

Nineteen patients with congenital adrenal hyperplasia (CAH) aged over 16 years were given a neuropsychological evaluation; no significant differences with individually matched normal controls were detected. CAH subjects, however, revealed slightly higher IQs with respect to the expected distribution. No significant learning disabilities could be detected. Fifteen patients underwent nuclear magnetic resonance (NMR); 4 subjects showed small areas of increased signal intensity in the white matter, without prevalence of side; this finding did not correlate with clinical and cognitive characteristics. The results are discussed in the light of possible hormonal influences.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Inteligência/fisiologia , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Adolescente , Hiperplasia Suprarrenal Congênita/fisiopatologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Androgênios/sangue , Encéfalo/patologia , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino
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