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1.
Phys Rev Lett ; 132(8): 082501, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457706

RESUMO

The structure and decay of the most neutron-rich beryllium isotope, ^{16}Be, has been investigated following proton knockout from a high-energy ^{17}B beam. Two relatively narrow resonances were observed for the first time, with energies of 0.84(3) and 2.15(5) MeV above the two-neutron decay threshold and widths of 0.32(8) and 0.95(15) MeV, respectively. These were assigned to be the ground (J^{π}=0^{+}) and first excited (2^{+}) state, with E_{x}=1.31(6) MeV. The mass excess of ^{16}Be was thus deduced to be 56.93(13) MeV, some 0.5 MeV more bound than the only previous measurement. Both states were observed to decay by direct two-neutron emission. Calculations incorporating the evolution of the wave function during the decay as a genuine three-body process reproduced the principal characteristics of the neutron-neutron energy spectra for both levels, indicating that the ground state exhibits a strong spatially compact dineutron component, while the 2^{+} level presents a far more diffuse neutron-neutron distribution.

2.
Phys Rev Lett ; 129(1): 012501, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35841541

RESUMO

A narrow near-threshold proton-emitting resonance (E_{x}=11.4 MeV, J^{π}=1/2^{+}, and Γ_{p}=4.4 keV) was directly observed in ^{11}B via proton resonance scattering. This resonance was previously inferred in the ß-delayed proton emission of the neutron halo nucleus ^{11}Be. The good agreement between both experimental results serves as a ground to confirm the existence of such exotic decay and the particular behavior of weakly bound nuclei coupled to the continuum. R-matrix analysis shows a sizable partial decay width for both, proton and α (Γ_{α}=11 keV) emission channels.

6.
Dermatol Online J ; 18(8): 12, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22948062

RESUMO

A 48-year-old woman developed drug-induced subacute lupus erythematosus while taking lamotrigine. The eruption resolved after discontinuance of lamotrigine, suggesting this drug as the cause.


Assuntos
Anticonvulsivantes/efeitos adversos , Lúpus Eritematoso Cutâneo/induzido quimicamente , Triazinas/efeitos adversos , Toxidermias/imunologia , Feminino , Humanos , Lamotrigina , Lúpus Eritematoso Cutâneo/imunologia , Pessoa de Meia-Idade
12.
Actas Dermosifiliogr ; 102(2): 114-20, 2011 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-21306689

RESUMO

BACKGROUND: Congenital melanocytic nevus is a benign proliferation of melanocytes that is present at birth or develops in the first months of life. Although such lesions are common, few studies have analyzed their prevalence in Spain. OBJECTIVES: The aim of this study was to define the prevalence and most frequent anatomical areas affected by congenital melanocytic nevi in our health service area. We also analyzed the influence of maternal and neonatal factors in the development of these lesions. PATIENTS AND METHODS: We performed a prospective study of 1000 consecutive neonates seen in the first 72hours of life in the perinatology clinic of the Pediatrics Department of Hospital Arquitecto Marcide in Ferrol, Spain, recording specific maternal and neonatal variables and the size and site of congenital melanocytic nevi if present. RESULTS: Fourteen infants (10 girls and 4 boys; 12 white European, 2 North African; 1.4% of the study population) presented at least 1 melanocytic nevus. None had more than 1 lesion. Eight of the nevi were located on the trunk, 2 on the face, 2 on the upper limbs, and 2 on the lower limbs. The diameter of the lesions was less than 1.5 cm in half of cases and between 1.5 and 3.5 cm in the remainder. CONCLUSIONS: There was a higher prevalence of congenital melanocytic nevi in preterm infants, females, and nonwhite infants. Maternal age, number of previous pregnancies, and birth weight do not appear to influence the prevalence of these lesions.


Assuntos
Nevo Pigmentado/congênito , Nevo Pigmentado/epidemiologia , Neoplasias Cutâneas/congênito , Neoplasias Cutâneas/epidemiologia , Feminino , Humanos , Recém-Nascido , Masculino , Nevo Pigmentado/diagnóstico , Prevalência , Estudos Prospectivos , Neoplasias Cutâneas/diagnóstico , Espanha/epidemiologia
13.
Actas Dermosifiliogr ; 102(4): 264-9, 2011 May.
Artigo em Espanhol | MEDLINE | ID: mdl-21324425

RESUMO

BACKGROUND AND OBJECTIVES: Almost all newborn children have some sort of birthmark or transient benign skin lesion. Few studies, however, have analyzed their frequency, particularly in Spain. The aims of this study were to determine their prevalence in 1000 newborn children in the health care area of Ferrol in northwest Spain and to compare the results with those of 9 other studies with similar characteristics. PATIENTS AND METHODS: We undertook a descriptive study of 1000 newborn infants seen in the first 3 days of life at the neonatal clinic in the Department of Pediatrics, Hospital Arquitecto Marcide, Ferrol, Spain. Each infant was examined for the presence of 19 different transient benign skin lesions and 11 birthmarks. RESULTS: Birthmarks or benign skin lesions were present in 994 neonates (99.4%). Transient skin lesions were present in 99.2% and birthmarks in 72%. The 5 most prevalent lesions were sebaceous hyperplasia (75%), salmon patch (64.2%), hypertrichosis (59%), sucking calluses (54%), and palatine cysts (53.7%). CONCLUSIONS: The results of this study show that most neonates have benign skin lesions. The findings of studies to assess their frequency are influenced not only by geographic location (affecting variables such as climate, social and health care conditions, and ethnic group) but also by the timing of examination, the inclusion criteria applied, and the terminology used.


Assuntos
Dermatopatias/congênito , Calosidades/congênito , Calosidades/epidemiologia , Cistos/congênito , Cistos/epidemiologia , Etnicidade , Hemangioma Capilar/congênito , Hemangioma Capilar/epidemiologia , Humanos , Hiperplasia , Hipertricose/congênito , Hipertricose/epidemiologia , Ictiose Lamelar/epidemiologia , Recém-Nascido , Mancha Mongólica/congênito , Mancha Mongólica/epidemiologia , Síndromes Neoplásicas Hereditárias , Mancha Vinho do Porto/epidemiologia , Prevalência , Glândulas Sebáceas/patologia , Dermatopatias/epidemiologia , Neoplasias Cutâneas/congênito , Neoplasias Cutâneas/epidemiologia , Fatores Socioeconômicos , Espanha/epidemiologia
14.
Actas Dermosifiliogr ; 102(1): 24-7, 2011 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-21315858

RESUMO

BACKGROUND AND OBJECTIVES: salmon patch is a congenital venous malformation that usually affects the midline. Although it is very common, few studies have analyzed its prevalence or predisposing factors. The aim of this study was to determine the prevalence and clinical characteristics of salmon patch in a group of newborn infants from a health care area in northwest Spain and to assess its association with neonatal and maternal variables. PATIENTS AND METHODS: a descriptive study was undertaken of live newborn children seen in the neonatal unit of the Department of Pediatrics at Hospital Arquitecto Marcide, Ferrol, Spain between May 1, 2008 and January 31, 2009. The study protocol included collection of data on neonatal variables (including gestational age, sex, ethnic origin, weight, and presence and anatomical site of salmon patch) and maternal variables (including age and number of previous pregnancies). RESULTS: of the 600 newborn infants included in the study, 59% had salmon patches. The most commonly affected sites were the nape of the neck (226 infants, 37.6%) and eyelids (211 infants, 35.1%). In a number of cases, more than one part of the body was affected. There was a higher prevalence of salmon patch in full-term or post-term births, in girls, white children, heavier children, and infants born to mothers aged between 30 and 34 years or who had not been pregnant previously. CONCLUSIONS: salmon patch occurred most frequently on the nape of the neck, the eyelids, and the glabella. Its prevalence was associated with certain neonatal and maternal factors.


Assuntos
Mancha Vinho do Porto/epidemiologia , Adulto , Peso ao Nascer , Pálpebras , Feminino , Testa , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Idade Materna , Pescoço , Paridade , Mancha Vinho do Porto/patologia , Gravidez , Prevalência , Fatores de Risco , Espanha/epidemiologia
15.
Actas Dermosifiliogr ; 102(9): 726-9, 2011 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-21481821

RESUMO

At birth, vernix caseosa can cover the whole body surface or accumulate only on the back and in the skin folds. Interest in its composition and function and its possible applications in adults has increased in recent years. The objective of this study was to determine the prevalence of vernix caseosa in newborn infants in the health care area of Ferrol, Spain, and to assess its relationship with neonatal and maternal factors. We performed a prospective study of 1000 newborns seen within the first 3 days of life in our hospital. Vernix caseosa was observed in 42.9% of cases. The clinical profile associated with the presence of vernix caseosa was the following: healthy newborn girl with a high birth weight, born at term by normal vaginal delivery to a multiparous mother who had received medication and dietary supplements during pregnancy. The absence of vernix caseosa was associated with the presence of physiological scaling of the newborn and erythema toxicum neonatorum.


Assuntos
Dermatopatias/epidemiologia , Verniz Caseoso , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Prevalência , Estudos Prospectivos , Fatores de Risco , Espanha/epidemiologia
16.
Br J Dermatol ; 163(4): 743-51, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20618320

RESUMO

BACKGROUND: Suspected toenail onychomycosis is a frequent problem. Clinical diagnosis has been considered inadequate. OBJECTIVES: To assess the diagnostic accuracy of clinical findings for detecting fungi in toenails, and to develop and validate a clinical diagnostic rule aimed at improving dermatologists' diagnosis of onychomycosis. METHODS: A cross-sectional diagnostic study was performed including a total of 277 patients seen by 12 dermatologists. The gold standard was the presence of dermatophytes on culture or a positive nail plate biopsy. For each sign we described prevalence, sensitivity, specificity, positive and negative predictive values, and likelihood ratios for positive and negative results. We developed a diagnostic clinical rule and validated it in a subsample. RESULTS: Helpful findings to predict the presence of fungi are: previous diagnosis of fungal disease; abnormal plantar desquamation (affecting > 25% of the sole); onychomycosis considered the most probable diagnosis by a dermatologist; and presence of interdigital tinea. When dermatologists considered onychomycosis the most probable diagnosis and plantar desquamation was present (13% of patients), the positive predictive value for presence of fungi was 81%. When both signs were absent (34% of patients), the positive predictive value for absence of fungi was 71%. In other situations, clinical diagnosis might not give enough information to decide on therapy. CONCLUSIONS: In 13% of the patients (a large number in absolute terms), when dermatologists consider onychomycosis the most probable diagnosis and plantar desquamation is present, therapy should be started without any further test, as clinical diagnosis is at least as accurate as laboratory tests. In other situations, an optimal management strategy should be defined.


Assuntos
Dermatoses do Pé/diagnóstico , Onicomicose/diagnóstico , Adulto , Idoso , Arthrodermataceae/isolamento & purificação , Biópsia , Métodos Epidemiológicos , Feminino , Dermatoses do Pé/etiologia , Dermatoses do Pé/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Unhas/patologia , Onicomicose/etiologia , Onicomicose/patologia , Exame Físico
17.
Actas Dermosifiliogr ; 101(5): 444-7, 2010 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-20525488

RESUMO

Cutaneous collagenous vasculopathy is an idiopathic microangiopathy first described in 2000 by Salama and Rosenthal.It must not be confused with generalized essential telangiectasia. To date, all patients have been white men over the age of 50 years, most of whom had multiple pathologies, were taking multiple drugs, and had no family history of similar conditions or hemorrhagic disorders. The disease is characterized by the development of various numbers of telangiectases on the limbs, lower abdomen, chest, or back, with no involvement of the mucosas or nail bed. Histopathology shows dilated superficial cutaneous vessels with perivascular deposits of periodic acid-Schiff diastase-positive, eosinophilic hyaline material that exhibits positive immunoreactivity to collagen IV. We report a new case in a 68-year-old man with symmetrically distributed telangiectases on his forearms, lower abdomen, posterior thighs, lower legs, and dorsum of the feet.


Assuntos
Doenças do Colágeno , Dermatopatias Vasculares , Telangiectasia , Idoso , Doenças do Colágeno/patologia , Humanos , Masculino , Dermatopatias Vasculares/patologia , Telangiectasia/patologia
19.
Br J Dermatol ; 160(6): 1315-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19239464

RESUMO

BACKGROUND: Toenail disorders are frequent, especially onychomycosis. The interobserver variability of nail signs needs to be known before these signs can be confidently applied for diagnosis. OBJECTIVES: To describe observer agreement in toenail findings as described by dermatologists in standard clinical practice, focusing on signs that could be useful for diagnosis of onychomycosis. METHODS: Prospective cross-sectional study in five dermatology departments. Eighty-six patients with abnormal toenails that could have onychomycosis as a differential diagnosis were independently examined by a pair of dermatologists using a predefined questionnaire, to describe the presence of 10 findings on previous history and 14 physical signs. RESULTS: Agreement was fine for previous history findings: it was very good (kappa > 0.81) for previous diagnosis of diabetes, smoking and use of public dressing rooms or swimming pools. Agreement was good (kappa 0.61-0.80) for immune suppression (drugs or cancer), previous diagnosis of fungal disease and worsening in the last year. It was moderate (kappa 0.41-0.60) for previous diagnosis of arterial disease, trauma induced by work or sports, and distal vs. proximal or lateral vs. central start of the lesion. Agreement was worse for physical signs: we found good agreement for the presence of the same disease in fingernails, abnormal plantar desquamation, deformity causing nail trauma, and subungual hyperkeratosis. It was moderate for the presence of nail destruction, tinea interdigitalis, onycholysis, and the type of material obtained by subungual curettage (dust vs. hard). Agreement was fair (kappa 0.21-0.40) for the presence of longitudinal or transverse striae, trachyonychia, pachyonychia, and change in colour of the nail plate. Pitting was too infrequent to allow for kappa calculation. Chance expected agreement was between 51% and 84% for all signs except pitting. CONCLUSIONS: Agreement is adequate for most signs. It is low for the presence of longitudinal or transverse striae, trachyonychia, and change in colour of the nail plate. Pitting is rare in toenails.


Assuntos
Dermatoses do Pé/diagnóstico , Doenças da Unha/diagnóstico , Idoso , Competência Clínica , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Unhas , Variações Dependentes do Observador , Onicomicose/diagnóstico , Estudos Prospectivos , Índice de Gravidade de Doença , Espanha , Inquéritos e Questionários
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