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The dynamics of a nuclear open quantum system could be revealed in the correlations between the breakup fragments of halo nuclei. The breakup mechanism of a proton halo nuclear system is of particular interest as the Coulomb polarization may play an important role, which, however, remains an open question. Here we use a highly efficient silicon detector array and measure the correlations between the breakup fragments of 8B incident on 120Sn at near-barrier energies. The energy and angular correlations can be explained by a fully quantum mechanical method based on the state-of-the-art continuum discretized coupled channel calculations. The results indicate that, compared to the neutron halo nucleus 6He, 8B presents distinctive reaction dynamics: the dominance of the elastic breakup. This breakup occurs mainly via the short-lived continuum states, almost exhausts the 7Be yield, indicating the effect of Coulomb polarization on the proton halo state. The correlation information reveals that the prompt breakup mechanism dominates, occurring predominantly on the outgoing trajectory. We also show that, as a large environment, the continuum of 8B breakup may not significantly influence elastic scattering and complete fusion.
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HLA-C*02:10:03 identified in a Venezuelan patient and characterized using next generation sequencing.
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OBJECTIVE: Maternal obesity is characterized by systemic low-grade inflammation and oxidative stress (OxS) with the contribution of fetal sex dimorphism. We recently described increased mitochondrial content (mtDNA) in placentas of obese pregnancies. Here, we quantify mtDNA and hepcidin as indexes of OxS and systemic inflammation in the obese maternal circulation. METHODS: Forty-one pregnant women were enrolled at elective cesarean section: 16 were normal weight (NW) and 25 were obese (OB). Obese women were further classified according to the presence/absence of maternal gestational diabetes mellitus (GDM); [OB/GDM(-)]: n = 15, [OB/GDM(+)]: n = 10. mtDNA and hepcidin were evaluated in blood (real-time PCR) and plasma (ELISA). RESULTS: mtDNA and hepcidin levels were significantly increased in OB/GDM(-) versus NW, significantly correlating with pregestational BMI. Male/female (M/F) ratio was equal in study groups, and overall F-carrying pregnancies showed significantly higher mtDNA and hepcidin levels than M-carrying pregnancies both in obese and normal weight mothers. CONCLUSIONS: Our results indicate a potential compensatory mechanism to increased obesity-related OxS and inflammation, indicated by the higher hepcidin levels found in obese mothers. Increased placental mitochondrial biogenesis, due to lipotoxic environment, may account for the greater mtDNA amount released in maternal circulation. This increase is namely related to F-carrying pregnancies, suggesting a gender-specific placental response.
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DNA Mitocondrial/metabolismo , Hepcidinas/metabolismo , Obesidade/metabolismo , Obesidade/patologia , Placenta/metabolismo , Placenta/patologia , Adulto , Estudos de Casos e Controles , DNA Mitocondrial/análise , Feminino , Humanos , Inflamação/metabolismo , Inflamação/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mães , Estresse Oxidativo/fisiologia , Gravidez , Complicações na Gravidez/metabolismo , Complicações na Gravidez/patologiaRESUMO
Gamma-ray spectroscopy measurements at MHz counting rates have been carried out, for the first time, with a compact spectrometer based on a LaBr3 scintillator and silicon photomultipliers. The instrument, which is also insensitive to magnetic fields, has been developed in view of the upgrade of the gamma-ray camera diagnostic for α particle measurements in deuterium-tritium plasmas of the Joint European Torus. Spectra were measured up to 2.9 MHz with a projected energy resolution of 3%-4% in the 3-5 MeV range, of interest for fast ion physics studies in fusion plasmas. The results reported here pave the way to first time measurements of the confined α particle profile in high power plasmas of the next deuterium-tritium campaign at the Joint European Torus.
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A growing body of evidence links the analysis of the KIR genotype and the presence of their HLA-B and -C ligands to a wide repertoire of human diseases. We noticed that, using a panel of 184 Caucasoid donors, a limited number of HLA alleles were incorrectly supratyped by previously described pyrosequence-based assays. Here we describe a simple implementation of the reported methods that corrects all the discrepancies found with HLA-B and -C molecular typing and allows establishing a quick and high-throughput method for the determination of HLA-Bw4 I(80), Bw4T(80), Bw6 and HLA-C1 or -C2 supratype.
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Antígenos HLA-B/classificação , Antígenos HLA-C/classificação , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Teste de Histocompatibilidade/métodos , Análise de Sequência de DNA/métodos , Alelos , Sequência de Bases , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Humanos , Células Matadoras Naturais/imunologia , Tipagem Molecular/métodos , Receptores KIR/genética , Linfócitos T/imunologiaRESUMO
We report on experiments in which the Texas Petawatt laser irradiated a mixture of deuterium or deuterated methane clusters and helium-3 gas, generating three types of nuclear fusion reactions: D(d,^{3}He)n, D(d,t)p, and ^{3}He(d,p)^{4}He. We measured the yields of fusion neutrons and protons from these reactions and found them to agree with yields based on a simple cylindrical plasma model using known cross sections and measured plasma parameters. Within our measurement errors, the fusion products were isotropically distributed. Plasma temperatures, important for the cross sections, were determined by two independent methods: (1) deuterium ion time of flight and (2) utilizing the ratio of neutron yield to proton yield from D(d,^{3}He)n and ^{3}He(d,p)^{4}He reactions, respectively. This experiment produced the highest ion temperature ever achieved with laser-irradiated deuterium clusters.
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The plasma astrophysical S factor for the 3He(d,p)4He fusion reaction was measured for the first time at temperatures of few keV, using the interaction of intense ultrafast laser pulses with molecular deuterium clusters mixed with 3He atoms. Different proportions of D2 and 3He or CD4 and 3He were mixed in the gas target in order to allow the measurement of the cross section for the 3He(d,p)4He reaction. The yield of 14.7 MeV protons from the 3He(d,p)4He reaction was measured in order to extract the astrophysical S factor at low energies. Our result is in agreement with other S factor parametrizations found in the literature.
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Two different methods have been employed to determine the plasma temperature in a laser-cluster fusion experiment on the Texas Petawatt laser. In the first, the temperature was derived from time-of-flight data of deuterium ions ejected from exploding D(2) or CD(4) clusters. In the second, the temperature was measured from the ratio of the rates of two different nuclear fusion reactions occurring in the plasma at the same time: D(d,(3)He)n and (3)He(d,p)(4)He. The temperatures determined by these two methods agree well, which indicates that (i) the ion energy distribution is not significantly distorted when ions travel in the disassembling plasma; (ii) the kinetic energy of deuterium ions, especially the "hottest part" responsible for nuclear fusion, is well described by a near-Maxwellian distribution.
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Quantum-mechanical shell effects are expected to strongly enhance nuclear binding on an "island of stability" of superheavy elements. The predicted center at proton number Z = 114, 120, or 126 and neutron number N = 184 has been substantiated by the recent synthesis of new elements up to Z = 118. However, the location of the center and the extension of the island of stability remain vague. High-precision mass spectrometry allows the direct measurement of nuclear binding energies and thus the determination of the strength of shell effects. Here, we present such measurements for nobelium and lawrencium isotopes, which also pin down the deformed shell gap at N = 152.
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The masses of ten proton-rich nuclides, including the N=Z+1 nuclides 85Mo and 87Tc, were measured with the Penning trap mass spectrometer SHIPTRAP. Compared to the Atomic Mass Evaluation 2003 a systematic shift of the mass surface by up to 1.6 MeV is observed causing significant abundance changes of the ashes of astrophysical x-ray bursts. Surprisingly low α separation energies for neutron-deficient Mo and Tc are found, making the formation of a ZrNb cycle in the rp process possible. Such a cycle would impose an upper temperature limit for the synthesis of elements beyond Nb in the rp process.
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The mass of an atom incorporates all its constituents and their interactions. The difference between the mass of an atom and the sum of its building blocks (the binding energy) is a manifestation of Einstein's famous relation E = mc(2). The binding energy determines the energy available for nuclear reactions and decays (and thus the creation of elements by stellar nucleosynthesis), and holds the key to the fundamental question of how heavy the elements can be. Superheavy elements have been observed in challenging production experiments, but our present knowledge of the binding energy of these nuclides is based only on the detection of their decay products. The reconstruction from extended decay chains introduces uncertainties that render the interpretation difficult. Here we report direct mass measurements of trans-uranium nuclides. Located at the farthest tip of the actinide species on the proton number-neutron number diagram, these nuclides represent the gateway to the predicted island of stability. In particular, we have determined the mass values of (252-254)No (atomic number 102) with the Penning trap mass spectrometer SHIPTRAP. The uncertainties are of the order of 10 keV/c(2) (representing a relative precision of 0.05 p.p.m.), despite minute production rates of less than one atom per second. Our experiments advance direct mass measurements by ten atomic numbers with no loss in accuracy, and provide reliable anchor points en route to the island of stability.
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We report on the first measurement of the beta+ and orbital electron-capture decay rates of 140Pr nuclei with the simplest electron configurations: bare nuclei, hydrogenlike, and heliumlike ions. The measured electron-capture decay constant of hydrogenlike 140Pr58+ ions is about 50% larger than that of heliumlike 140Pr57+ ions. Moreover, 140Pr ions with one bound electron decay faster than neutral 140Pr0+ atoms with 59 electrons. To explain this peculiar observation one has to take into account the conservation of the total angular momentum, since only particular spin orientations of the nucleus and of the captured electron can contribute to the allowed decay.
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We report on an infant with multi-system disease including liver fibrosis, right microphthalmia with cataract, interstitial pneumonitis, and hyperechoic lesions in the basal ganglia and in the periventricular and thalamic regions. Prenatal ascites with hepatomegaly concomitantly with detection of cytomegalovirus (CMV) DNA in the amniotic fluid, following recurrent maternal CMV infection, had been shown. Although CMV culture and DNA detection were negative in the urine, the infant was given foscarnet because CMV infection was demonstrated in the liver by DNA detection and immunohistochemical staining. Favorable clinical outcome and absence of CMV in the liver were subsequently shown. Our case suggests that congenital CMV disease following maternal recurrence may not be associated with disseminated infection but only with intracellular infection. The diagnosis should therefore be based on CMV detection in the involved organs. Moreover, this is the first report on the possible efficacy and safety of foscarnet for therapy of immunocompetent infants with congenital CMV disease.
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Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Foscarnet/uso terapêutico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adulto , Antivirais/administração & dosagem , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Citomegalovirus/ultraestrutura , Infecções por Citomegalovirus/diagnóstico por imagem , Infecções por Citomegalovirus/transmissão , DNA Viral/análise , Diagnóstico Diferencial , Feminino , Foscarnet/administração & dosagem , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Cirrose Hepática/embriologia , Masculino , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico por imagem , Ultrassonografia Pré-NatalRESUMO
Uterine anomalies implicated in female subfertility, implantation failure and miscarriages can often be detected often by two-dimensional transvaginal (2D TV) ultrasound scanning. When used as a screening test TV ultrasound has provided sensitivity rates of up to 100% about uterine anomalies. Improved depiction has been achieved with the development of hysterosalpingosonography (HSSG). The anechoic interface provided by the saline solution allows the examiner to determine whether an abnormality is intracavitary, endometrial, or submucosal. The aim of this study was to evaluate the role of 2D TV contrast sonography and 3D TV ultrasound in the diagnosis of congenital uterine anomalies in comparison with their appearance of hysterosalpingosonography findings.
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Anormalidades Congênitas/diagnóstico por imagem , Endossonografia/métodos , Histerossalpingografia/métodos , Imageamento Tridimensional/métodos , Útero/anormalidades , Útero/diagnóstico por imagem , Adolescente , Adulto , Estudos de Coortes , Meios de Contraste , Feminino , Humanos , Infertilidade Feminina , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica , Estudos Retrospectivos , Sensibilidade e Especificidade , Doenças Uterinas/diagnóstico por imagem , Doenças Uterinas/fisiopatologiaRESUMO
Barth syndrome (BTHS) is a rare, X-linked, recessive disorder that affects almost exclusively males. It is characterized by short stature, cardioskeletal myopathy, cyclic neutropenia, increased excretion of 3-methylglutaconic acid in the urine, and moderate hypocholesterolemia. The objective of the present study was to assess whether BTHS presents with a cognitive phenotype. Preliminary data were collected from five kindergarten or first-grade boys with BTHS. An abbreviated psychoeducational test battery was administered to each boy, and parents of each boy completed standardized behavior rating scales. Data from 120 boys of similar age or grade level were used for one comparison group; a subset of this sample comprised a comparison group that was individually matched on age and grade level to one of the five boys with BTHS. Preliminary data reflect a higher incidence of cognitive difficulties in boys with BTHS relative to both comparison groups. Boys with BTHS had significantly lower visual spatial skills, but comparable reading-related skills, when compared with either group. Although based on a small sample size, the preliminary data presented in this work are the first indication of a cognitive phenotype associated with BTHS.
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Transtornos Cognitivos/genética , Glutaratos/urina , Transtornos do Crescimento/psicologia , Doenças Musculares/psicologia , Neutropenia/psicologia , Criança , Pré-Escolar , Feminino , Genética Comportamental , Transtornos do Crescimento/genética , Humanos , Testes de Inteligência , Masculino , Músculo Esquelético/patologia , Doenças Musculares/genética , Miocárdio/patologia , Neutropenia/genética , Fenótipo , SíndromeRESUMO
Glutaredoxins (GRXs) are ubiquitous GSH-dependent oxidoreductases, which catalyze the reduction of protein-glutathionyl-mixed disulfides and are considered to play an important role in the enzymatic regulation of redox-sensitive proteins. In this paper, we describe the identification and characterization of a new human homologue of the SH3BGR gene, named SH3BGRL3 (SH3 domain binding glutamic acid-rich protein like 3). SH3BGRL3 is widely expressed and codes for a highly conserved small protein, which shows a significant similarity to Glutaredoxin 1 (GRX1) of Escherichia coli and is predicted to belong to the Thioredoxin Superfamily. However, the SH3BGRL3 protein lacks both the conserved cysteine residues, which characterize the enzymatic active site of GRX. This structural feature raises the possibility that SH3BGRL3 could function as an endogenous modulator of GRX biological activity. EGFP-SH3BGRL3 fusion protein expressed in COS-7 cells localizes both to the nucleus and to the cytoplasm. The SH3BGRL3 gene was mapped to chromosome 1p34.3-35.
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Cromossomos Humanos Par 1 , Escherichia coli/genética , Proteínas Musculares/genética , Oxirredutases , Proteínas/genética , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sequência de Bases , Células COS , Linhagem Celular , Chlorocebus aethiops , Mapeamento Cromossômico , Clonagem Molecular , Sequência Conservada , Glutarredoxinas , Humanos , Células Jurkat , Camundongos , Dados de Sequência Molecular , Proteínas Musculares/química , Especificidade de Órgãos , Proteínas/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Linfócitos T , Tiorredoxinas/química , Tiorredoxinas/genética , Transcrição Gênica , Transfecção , Células Tumorais CultivadasRESUMO
This study was designed to examine the effect of the fragile X premutation (pM) on cognitive function and behavior. Participants included 14 children (7 males, 7 females) with the fragile X pM and 14 children without the fragile X pM (and without the fragile X full mutation [fM]), each of whom was matched by age and gender with one of the participants from the pM group. The children ranged in age from 3 years, 1 month, to 17 years, 11 months. Participants were individually administered measures of intellectual functioning, academic achievement, and visual motor integration. Parent rating scales of problem behaviors were completed. Group differences were examined using nonparametric statistics. No statistically significant differences were found between the premutation and nonpremutation groups. The results from this study are consistent with the hypothesis that the premutation does not, in general, have an effect on a child's development. However, this does not preclude cases where specific factors may lead to a specific phenotype.
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Transtornos do Comportamento Infantil/genética , Síndrome do Cromossomo X Frágil/genética , Deficiências da Aprendizagem/genética , Proteínas do Tecido Nervoso/genética , Proteínas de Ligação a RNA , Repetições de Trinucleotídeos , Adolescente , Criança , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/psicologia , Pré-Escolar , Feminino , Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil/diagnóstico , Síndrome do Cromossomo X Frágil/psicologia , Humanos , Testes de Inteligência , Deficiências da Aprendizagem/diagnóstico , Deficiências da Aprendizagem/psicologia , Masculino , Mutação , Determinação da Personalidade , FenótipoRESUMO
The purpose of this study was to assess the predictive value of kindergarten teachers' ratings of pupils for later first-grade academic achievement. Kindergarten students were rated by their teachers on a variety of variables, including math and reading performance, teacher concerns, and amount of learning relative to peers. These variables were then analyzed with respect to outcome measures for math and reading ability administered in the first grade. The teachers' ratings of academic performance were significantly correlated with scores on the outcome measures. Analyses were also carried out to determine sensitivity, specificity, and predictive values of the different teacher ratings. The results indicated high overall accuracy, sensitivity, specificity, and negative predictive value for the ratings. Positive predictive value tended to be lower. A recommendation to follow from these results is that teacher ratings of this sort be used to determine which children should receive cognitive screening measures to further enhance identification of children at risk for learning disability. However, this recommendation is limited by the lack of empirically supported screening measures for math disability versus well-supported screening tools for reading disability.
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Deficiências da Aprendizagem/diagnóstico , Baixo Rendimento Escolar , Criança , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/psicologia , Pré-Escolar , Dislexia/diagnóstico , Dislexia/psicologia , Feminino , Humanos , Deficiências da Aprendizagem/psicologia , Estudos Longitudinais , Masculino , Matemática , Determinação da Personalidade/estatística & dados numéricos , Psicometria/estatística & dados numéricos , Leitura , Reprodutibilidade dos Testes , Medição de RiscoRESUMO
The present study examined whether indicators of math learning disability are observed in 5- and 6-year-olds with neurofibromatosis type 1 (NF1) and in 5- to 6-year-old girls with Turner syndrome or fragile X syndrome. Data from 14 girls with Turner syndrome, 9 girls with fragile X syndrome, and 11 children with NF1 were compared to data from control participants matched on age, sex, IQ score, and grade level. The results indicate that girls with fragile X syndrome or Turner syndrome are significantly more likely to have specific math difficulties relative to their control group, with a larger effect size demonstrated by the group with Turner syndrome. Young children with NF1 had a heterogeneous profile not suggestive of specific math disability. The results are discussed in terms of their implications for understanding math disability subtypes and the identification of math difficulty in the early school years.