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1.
Int J Mol Sci ; 24(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834164

RESUMO

Duchenne muscular dystrophy (DMD) is a severe progressive muscle disease that mainly affects boys due to X-linked recessive inheritance. In most affected individuals, MLPA or sequencing-based techniques detect deletions, duplications, or point mutations in the dystrophin-encoding DMD gene. However, in a small subset of patients clinically diagnosed with DMD, the molecular cause is not identified with these routine methods. Evaluation of the 60 DMD patients in our center revealed three cases without a known genetic cause. DNA samples of these patients were analyzed using whole-exome sequencing (WES) and, if unconclusive, optical genome mapping (OGM). WES led to a diagnosis in two cases: one patient was found to carry a splice mutation in the DMD gene that had not been identified during previous Sanger sequencing. In the second patient, we detected two variants in the fukutin gene (FKTN) that were presumed to be disease-causing. In the third patient, WES was unremarkable, but OGM identified an inversion disrupting the DMD gene (~1.28 Mb) that was subsequently confirmed with long-read sequencing. These results highlight the importance of reanalyzing unsolved cases using WES and demonstrate that OGM is a useful method for identifying large structural variants in cases with unremarkable exome sequencing.


Assuntos
Distrofia Muscular de Duchenne , Humanos , Masculino , Inversão Cromossômica , Mapeamento Cromossômico , Distrofina/genética , Sequenciamento do Exoma , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Mutação
2.
Phys Rev Lett ; 131(26): 262501, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38215380

RESUMO

The excited states of unstable ^{20}O were investigated via γ-ray spectroscopy following the ^{19}O(d,p)^{20}O reaction at 8 AMeV. By exploiting the Doppler shift attenuation method, the lifetimes of the 2_{2}^{+} and 3_{1}^{+} states were firmly established. From the γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+} and 3_{1}^{+} states, the B(E2) and B(M1) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of γ-ray transition probabilities with the valence space in medium similarity renormalization group ab initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab initio approaches using chiral effective field theory forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab initio models.

3.
J Fr Ophtalmol ; 44(4): 509-518, 2021 Apr.
Artigo em Francês | MEDLINE | ID: mdl-33632627

RESUMO

PURPOSE: To evaluate long terms outcomes of botulinum toxin in infantile esotropia by measuring the amount of microtropia 24 months after injection. Secondary purpose was to identify predictive factors of microtropia. METHODS: A retrospective, single-center study was performed at the university medical center in Bordeaux between 2001 and 2018, including all patients with infantile esotropia greater than 20 D. All patients received 5 or 7,5 IU of botulinum toxin A in each medial rectus, once or twice depending on the angle of deviation after the first injection and after wearing full optical correction at least two months. We noted the angle at 1, 6, 12 and 24 months, the occurrence of any complications and the need for later strabismus surgery. The primary endpoint was the achievement of a microtropia less than 8 diopters (D) at 24 months post-injection. We evaluated the predictive factors for microtropia with a Fischer's test. RESULTS: We included 30 patients with esotropia greater than 20 D. The mean follow-up after injection was 48 months ±30. The mean age was 16.24 months (7-29 months) with a female predominance in the population (SR=0.43). The mean pre-injection deviation was 41.25±12.17 D. The majority of patients were mildly (40%) or moderately (40%) hyperopic. At 24 months, 46.7% microtropias were obtained (95% CI: 28.9%-64.5%). The change in mean angle at 1, 6, 12 and 24 months post-injection was -8.57±25.21 D; 14.48±13.40 D; 18.38±12.07 D and 21.23±14.97 D, respectively. No factors were predictive of microtropia. Of the 30 children, 3 had transient ptosis requiring strips and 12 showed an exotropia at 1 month. All complications were self-limited and without consequences. 3 children had a second injection of botulinum toxin, which in 2/3 of the cases resulted in a long-lasting microtropia. 26.7% (n=8) of the children underwent secondary surgery. Obtaining a microtropia 24 months after injection statistically significantly reduced the need for secondary strabismus surgery: 92.9% P=0.039% CI 95% (0.002; 1.0606). CONCLUSION: Botulinum toxin appears to be a less invasive and more conservative alternative to surgery in children with infantile esotropia. In 46.7% of cases, microtropia is achieved. An improvement was noted in 90% (n=27) of the children with a reduction of half (21.23 D) of the mean post-injection angle at 24 months. When effective, it significantly reduces the need for secondary surgery.


Assuntos
Toxinas Botulínicas Tipo A , Esotropia , Fármacos Neuromusculares , Toxinas Botulínicas Tipo A/efeitos adversos , Criança , Esotropia/tratamento farmacológico , Esotropia/cirurgia , Feminino , Humanos , Lactente , Masculino , Fármacos Neuromusculares/efeitos adversos , Músculos Oculomotores , Procedimentos Cirúrgicos Oftalmológicos , Estudos Retrospectivos , Resultado do Tratamento , Visão Binocular
4.
Nature ; 590(7847): 566-570, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33627809

RESUMO

When a heavy atomic nucleus splits (fission), the resulting fragments are observed to emerge spinning1; this phenomenon has been a mystery in nuclear physics for over 40 years2,3. The internal generation of typically six or seven units of angular momentum in each fragment is particularly puzzling for systems that start with zero, or almost zero, spin. There are currently no experimental observations that enable decisive discrimination between the many competing theories for the mechanism that generates the angular momentum4-12. Nevertheless, the consensus is that excitation of collective vibrational modes generates the intrinsic spin before the nucleus splits (pre-scission). Here we show that there is no significant correlation between the spins of the fragment partners, which leads us to conclude that angular momentum in fission is actually generated after the nucleus splits (post-scission). We present comprehensive data showing that the average spin is strongly mass-dependent, varying in saw-tooth distributions. We observe no notable dependence of fragment spin on the mass or charge of the partner nucleus, confirming the uncorrelated post-scission nature of the spin mechanism. To explain these observations, we propose that the collective motion of nucleons in the ruptured neck of the fissioning system generates two independent torques, analogous to the snapping of an elastic band. A parameterization based on occupation of angular momentum states according to statistical theory describes the full range of experimental data well. This insight into the role of spin in nuclear fission is not only important for the fundamental understanding and theoretical description of fission, but also has consequences for the γ-ray heating problem in nuclear reactors13,14, for the study of the structure of neutron-rich isotopes15,16, and for the synthesis and stability of super-heavy elements17,18.

5.
Phys Rev Lett ; 125(10): 102502, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32955302

RESUMO

The low-spin structure of the semimagic ^{64}Ni nucleus has been considerably expanded: combining four experiments, several 0^{+} and 2^{+} excited states were identified below 4.5 MeV, and their properties established. The Monte Carlo shell model accounts for the results and unveils an unexpectedly complex landscape of coexisting shapes: a prolate 0^{+} excitation is located at a surprisingly high energy (3463 keV), with a collective 2^{+} state 286 keV above it, the first such observation in Ni isotopes. The evolution in excitation energy of the prolate minimum across the neutron N=40 subshell gap highlights the impact of the monopole interaction and its variation in strength with N.

6.
Phys Rev Lett ; 120(16): 167601, 2018 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-29756940

RESUMO

The three-dimensional distribution of the x-ray diffuse scattering intensity of BaTiO_{3} has been recorded in a synchrotron experiment and simultaneously computed using molecular dynamics simulations of a shell model. Together, these have allowed the details of the disorder in paraelectric BaTiO_{3} to be clarified. The narrow sheets of diffuse scattering, related to the famous anisotropic longitudinal correlations of Ti ions, are shown to be caused by the overdamped anharmonic soft phonon branch. This finding demonstrates that the occurrence of narrow sheets of diffuse scattering agrees with a displacive picture of the cubic phase of this textbook ferroelectric material. The presented methodology allows one to go beyond the harmonic approximation in the analysis of phonons and phonon-related scattering.

7.
Phys Rev Lett ; 118(16): 162502, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28474931

RESUMO

A search for shape isomers in the ^{66}Ni nucleus was performed, following old suggestions of various mean-field models and recent ones, based on state-of-the-art Monte Carlo shell model (MCSM), all considering ^{66}Ni as the lightest nuclear system with shape isomerism. By employing the two-neutron transfer reaction induced by an ^{18}O beam on a ^{64}Ni target, at the sub-Coulomb barrier energy of 39 MeV, all three lowest-excited 0^{+} states in ^{66}Ni were populated and their γ decay was observed by γ-coincidence technique. The 0^{+} states lifetimes were assessed with the plunger method, yielding for the 0_{2}^{+}, 0_{3}^{+}, and 0_{4}^{+} decay to the 2_{1}^{+} state the B(E2) values of 4.3, 0.1, and 0.2 Weisskopf units (W.u.), respectively. MCSM calculations correctly predict the existence of all three excited 0^{+} states, pointing to the oblate, spherical, and prolate nature of the consecutive excitations. In addition, they account for the hindrance of the E2 decay from the prolate 0_{4}^{+} to the spherical 2_{1}^{+} state, although overestimating its value. This result makes ^{66}Ni a unique nuclear system, apart from ^{236,238}U, in which a retarded γ transition from a 0^{+} deformed state to a spherical configuration is observed, resembling a shape-isomerlike behavior.

8.
Phys Rev Lett ; 115(22): 222502, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26650299

RESUMO

The isospin mixing was deduced in the compound nucleus ^{80}Zr at an excitation energy of E^{*}=54 MeV from the γ decay of the giant dipole resonance. The reaction ^{40}Ca+^{40}Ca at E_{beam}=136 MeV was used to form the compound nucleus in the isospin I=0 channel, while the reaction ^{37}Cl+^{44}Ca at E_{beam}=95 MeV was used as the reference reaction. The γ rays were detected with the AGATA demonstrator array coupled with LaBr_{3}:Ce detectors. The temperature dependence of the isospin mixing was obtained and the zero-temperature value deduced. The isospin-symmetry-breaking correction δ_{C} used for the Fermi superallowed transitions was extracted and found to be consistent with ß-decay data.

11.
Phys Rev Lett ; 113(9): 092501, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-25215980

RESUMO

Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, J(π)=0+ ground state of (62)Ge into excited states of the odd-odd N=Z nucleus (62)Ga. The experiment is performed at GSI Helmholtzzentrum für Shwerionenforshung with the (62)Ge ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14) ms is measured for the (62)Ge ground state. Six excited states of (62)Ga, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T=0 proton-neutron correlations in (62)Ga.

12.
Phys Rev Lett ; 113(1): 012501, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-25032921

RESUMO

The properties of pygmy dipole states in 208Pb were investigated using the 208Pb(17O, 17O'γ) reaction at 340 MeV and measuring the γ decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted γ rays and of the scattered particles were measured. The results are compared with (γ, γ') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2+ and 3- states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first time. This has allowed us to extract the isoscalar component of the 1- excited states from 4 to 8 MeV.

13.
J Phys Condens Matter ; 26(14): 145602, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24637427

RESUMO

Using a combination of local density approximation and dynamical mean-field theory calculations, we explore the correlated electronic structure of a member of the layered iron oxychalcogenides group, Na2Fe2OSe2. We find that the parent compound is a multi-orbital Mott insulator. Surprisingly, and somewhat reminiscently of the underdoped high-Tc cuprate scenario, carrier localization is found to persist upon hole doping because the chemical potential lies in a gap structure with almost vanishing density of states. On the other hand, in remarkable contrast, electron doping drives an orbital-selective metallic phase with coexisting pseudogapped (Mott-localized) and itinerant carriers. These remarkably contrasting behaviors in a single system thus stem from drastic electronic reconstruction caused by large-scale transfer of dynamical spectral weight involving states with distinct orbital character at low energies, fitting the oxychalcogenides neatly into the increasingly visible pattern for Fe-based systems of having orbital-selective Mott phases. We detail the implications that follow from our analysis, and discuss the nature and symmetries of the superconductive states that may arise upon appropriately doping or pressurizing Na2Fe2OSe2.


Assuntos
Calcogênios/química , Elétrons , Compostos de Ferro/química , Modelos Químicos , Selênio/química , Sódio/química , Eletricidade Estática , Temperatura , Transistores Eletrônicos
14.
Ultraschall Med ; 34(3): 280-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23616066

RESUMO

PURPOSE: To assess the impact of different vascular patterns at contrast-enhanced ultrasound (CEUS) on the characterization of small liver nodules (10-30 mm) in cirrhosis and to determine whether primary nodules and recurrent nodules (after a previously treated hepatocellular carcinoma) display variations in enhancement pattern. MATERIALS AND METHODS: A total of 135 cirrhotic patients were evaluated. A diagnosis of hepatocellular carcinoma (HCC) was established according to AASLD Guidelines, based on imaging (computed tomography and/or magnetic resonance) or liver biopsy. All patients underwent CEUS. Different CEUS patterns were evaluated in terms of diagnostic accuracy: HYPER-HYPO: Arterial hyperenhancement followed by washout (hypoechoic appearance compared with surrounding parenchyma) in late phase; HYPER-ISO: Arterial hyperenhancement followed by isoenhancement (isoechoic appearance) in late phase; ISO-ISO: Isoenhancement in all vascular phases. RESULTS: A total of 155 consecutive primary (n = 90) or recurrent (n = 65) nodules were detected. HCC was diagnosed in 127 nodules (71 primary, 56 recurrent). A characteristic HYPER-HYPO CEUS pattern was revealed in 52/127 (40.9%) HCCs (31 primary, 21 recurrent) giving a positive predictive value (PPV) of 98% (97% primary, 100% recurrent) and an accuracy of 51% (54% primary, 46% recurrent). A HYPER-ISO pattern was noted in 46 HCCs (31 primary, 15 recurrent). Assuming this pattern to also be indicative of HCC, the PPV and accuracy were 94% (93% primary, 97% recurrent) and 77% (84% primary, 68% recurrent), respectively. An ISO-ISO pattern was present in 29 HCCs (9 primary, 20 recurrent) and 22 non-HCCs (14 primary, 8 recurrent). CONCLUSION: These data confirm that the HYPER-HYPO pattern at CEUS is definitely diagnostic for HCC in cirrhosis and that the HYPER-ISO pattern has a similar PPV, indicating that this pattern is highly suspicious for HCC. The ISO-ISO pattern was found in > 50% of recurrent nodules and indicates a high risk of HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste , Hiperplasia Nodular Focal do Fígado/diagnóstico por imagem , Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Fosfolipídeos , Hexafluoreto de Enxofre , Idoso , Biópsia , Carcinoma Hepatocelular/patologia , Feminino , Hiperplasia Nodular Focal do Fígado/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Recidiva Local de Neoplasia/patologia , Sensibilidade e Especificidade , Ultrassonografia
16.
Phys Rev Lett ; 111(24): 242504, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24483649

RESUMO

The γ-ray strength function of 56Fe has been measured from proton-γ coincidences for excitation energies up to ≈11 MeV. The low-energy enhancement in the γ-ray strength function, which was first discovered in the (3He,αγ)56Fe reaction, is confirmed with the (p,p'γ)56Fe experiment reported here. Angular distributions of the γ rays give for the first time evidence that the enhancement is dominated by dipole transitions.

17.
J Hepatol ; 57(6): 1258-67, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22871502

RESUMO

BACKGROUND & AIMS: Aim of the study was to assess the clinical impact of conventional transarterial chemoembolization (cTACE) repeated "on demand" on HCC outcome. Outcome measures were: response rate to first and repeated cTACE, recurrence rates and overall survival. METHODS: The outcome of 151 consecutive HCC patients submitted to a first cTACE from January 2004 to December 2005 was retrospectively analyzed. RESULTS: Complete radiological response (CR) was observed in 72/151 (48%), 34/60 (52%) and 12/22 (55%) patients after first, second and third cTACE, respectively. Recurrence rates at 6 and 12months were 37% and 61% after the first cTACE, and 40% and 59% after the second cTACE, respectively. Patients not achieving CR or with a recurrence after CR not treated with curative therapies were 94 and 84 after first and second cTACE, respectively. Of these, 60/94 (64%) and 22/84 (26%) were submitted to a second and third cTACE, respectively. Median overall survival was 32.0months but 25.0months excluding transplanted patients. Factors at the time of first cTACE associated with overall shorter survival at multivariate analysis were higher bilirubin, higher AFP and not achieving CR. CONCLUSIONS: CR and recurrence rates after first and second cTACE were similar. About 64% of patients were submitted to second cTACE, while only few patients (26%) were submitted to third cTACE using an "on demand" policy. These figures may be also useful for planning trials for the evaluation of the efficacy of repeated TACE vs. TACE combined with adjuvant treatments or vs. systemic treatments.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia
18.
J Fr Ophtalmol ; 34(10): 703-10, 2011 Dec.
Artigo em Francês | MEDLINE | ID: mdl-21885154

RESUMO

OBJECTIVE: To assess the effectiveness and tolerance of systemic metronidazole in the treatment of childhood ocular and cutaneous rosacea. METHOD: Single-center multidisciplinary retrospective study. PATIENTS: Children aged between 1 and 15, with ocular and/or cutaneous rosacea, treated in the pediatric ophthalmology and dermatology department of Bordeaux, France, from January 1996 to September 2009. RESULTS: Eleven patients out of 20 had ocular and cutaneous rosacea, three had ocular symptoms only, and six had cutaneous symptoms only. In 11 patients (55%), the ocular symptoms preceded the skin disease. Meibomian cyst and phlyctenular conjunctivitis were the main symptoms. Keratitis was seen in four patients and lower corneal ulcer in two cases. The papulopustular form was the most frequent dermatologic form. All patients with ocular involvement received first-line treatment of eyelid hygiene. No topical ophthalmic treatment such as corticosteroid or cyclosporine 0.5% or 2% was used. Thirteen patients who showed no improvement despite eyelid treatment, the association of ocular and cutaneous rosacea, severe ocular involvement with keratitis, and severe recurrent cutaneous rosacea were treated orally. Two patients, aged between 12 and 14 years, received treatment with an anti-inflammatory dose of doxycycline for 2 to 3 months and achieved complete remission. One 22-month-old patient received oral treatment with erythromycin at a dose of 250 mg three times daily for 4 months. Ten patients, aged 12 to 64 months, were treated with systemic Metronidazole. Treatment lasting at least 3 months at a dose between 20 and 30 mg/kg per day was necessary to obtain complete and lasting remission. An early cessation of treatment, before 3 months, seems associated with partial remission of the disease and early recurrence. In cases complicated by ocular keratitis and corneal ulcer, prolonged treatment lasting 6 months led to clinical remission. The short courses (3-6 months) were preferred to long-term administration to prevent neurological toxicity. Maintenance therapy was based on eyelid hygiene. No recurrences and no toxic effects were observed at a median of 48 ± 6 months. CONCLUSION: Childhood ocular rosacea is not rare, but is often misdiagnosed. It often precedes skin symptoms but it can remain isolated. Metronidazole could be alternative treatment for ocular and cutaneous rosacea in the pediatric population.


Assuntos
Metronidazol/uso terapêutico , Rosácea/tratamento farmacológico , Adolescente , Anti-Infecciosos/uso terapêutico , Criança , Pré-Escolar , Progressão da Doença , Oftalmopatias/tratamento farmacológico , Feminino , Humanos , Lactente , Comunicação Interdisciplinar , Masculino , População , Estudos Retrospectivos , Dermatopatias/tratamento farmacológico , Resultado do Tratamento
19.
Phys Rev Lett ; 103(5): 052501, 2009 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-19792492

RESUMO

Isospin symmetry breaking has been investigated in mass A=67 mirror nuclei through the experimental determination of the E1 strengths of analog electromagnetic transitions. Lifetimes of excited states have been measured in (67)Se and (67)As with the centroid shift method. Through the comparison of the B(E1) strengths of the mirror 9/2(+)-->7/2(-) transitions, the isovector and the isoscalar components of the electromagnetic transition amplitude were extracted. The presence of a large isoscalar component provides evidence for coherent contributions to isospin mixing, probably involving the isovector giant monopole resonance.

20.
Phys Rev Lett ; 102(24): 242502, 2009 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-19659003

RESUMO

The lifetimes of the first excited states of the N = 30 isotones (50)Ca and (51)Sc have been determined using the Recoil Distance Doppler Shift method in combination with the CLARA-PRISMA spectrometers. This is the first time such a method is applied to measure lifetimes of neutron-rich nuclei populated via a multinucleon transfer reaction. This extends the lifetime knowledge beyond the f_{7/2} shell closure and allows us to derive the effective proton and neutron charges in the fp shell near the doubly magic nucleus (48)Ca, using large-scale, shell-model calculations. These results indicate an orbital dependence of the core polarization along the fp shell.

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