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1.
Phys Rev Lett ; 132(12): 122701, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38579210

RESUMO

^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.

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.

3.
Eur Phys J A Hadron Nucl ; 58(12): 239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36514540

RESUMO

Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.

4.
Phys Rev Lett ; 124(20): 202502, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32501052

RESUMO

Taking benefit of the R3B/SOFIA setup to measure the mass and the nuclear charge of both fission fragments in coincidence with the total prompt-neutron multiplicity, the scission configurations are inferred along the thorium chain, from the asymmetric fission in the heavier isotopes to the symmetric fission in the neutron-deficient thorium. Against all expectations, the symmetric scission in the light thorium isotopes shows a compact configuration, which is in total contrast to what is known in the fission of the heavier thorium isotopes and heavier actinides. This new main symmetric scission mode is characterized by a significant drop in deformation energy of the fission fragments of about 19 MeV, compared to the well-known symmetric scission in the uranium-plutonium region.

5.
Phys Rev Lett ; 125(14): 142701, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064503

RESUMO

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.

6.
Phys Rev Lett ; 123(9): 092503, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31524478

RESUMO

A direct and complete measurement of isotopic fission-fragment yields of ^{239}U has been performed for the first time. The ^{239}U fissioning system was produced with an average excitation energy of 8.3 MeV in one-neutron transfer reactions between a ^{238}U beam and a ^{9}Be target at Coulomb barrier energies. The fission fragments were detected and isotopically identified using the VAMOS++ spectrometer at the GANIL facility. The measurement allows us to directly evaluate the fission models at excitation energies of fast neutrons, which are relevant for next-generation nuclear reactors. The present data, in agreement with model calculations, do not support the recently reported anomaly in the fission-fragment yields of ^{239}U, and they confirm the persistence of spherical shell effects in the Sn region at excitation energies exceeding the fission barrier by a few mega-electron volts.

7.
Phys Rev Lett ; 120(5): 052501, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29481189

RESUMO

Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R^{3}B/LAND setup with incident beam energies in the range of 300-450 MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type ^{A}O(p,2p)^{A-1}N have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.

8.
Phys Rev Lett ; 121(4): 042701, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30095928

RESUMO

We report on the measurement of the ^{7}Be(n,p)^{7}Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a ^{7}Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal ^{7}Li(p,n)^{7}Be reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p+^{7}Li reaction is also discussed.

9.
Phys Rev Lett ; 120(15): 152504, 2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756867

RESUMO

The emission of neutron pairs from the neutron-rich N=12 isotones ^{18}C and ^{20}O has been studied by high-energy nucleon knockout from ^{19}N and ^{21}O secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay ^{19}N(-1p)^{18}C^{*}→^{16}C+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a ^{14}C core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay ^{21}O(-1n)^{20}O^{*}→^{18}O+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the ^{16}O core and reduces the number of pairs.

10.
Phys Rev Lett ; 117(15): 152701, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768364

RESUMO

The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.

11.
Phys Rev Lett ; 113(3): 032504, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25083638

RESUMO

The isoscalar monopole response has been measured in the unstable nucleus (68)Ni using inelastic alpha scattering at 50A MeV in inverse kinematics with the active target MAYA at GANIL. The isoscalar giant monopole resonance (ISGMR) centroid was determined to be 21.1 ± 1.9 MeV and indications for a soft monopole mode are provided for the first time at 12.9 ± 1.0 MeV. Analysis of the corresponding angular distributions using distorted-wave-born approximation with random-phase approximation transition densities indicates that the L = 0 multipolarity dominates the cross section for the ISGMR and significantly contributes to the low-energy mode. The L=0 part of this low-energy mode, the soft monopole mode, is dominated by neutron excitations. This demonstrates the relevance of inelastic alpha scattering in inverse kinematics in order to probe both the ISGMR and isoscalar soft modes in neutron-rich nuclei.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38670490

RESUMO

INTRODUCTION: Preoperative anemia affects approximately one third of surgical patients. It increases the risk of blood transfusion and influences short- and medium-term functional outcomes, increases comorbidities, complications and costs. The "Patient Blood Management" (PBM) programs, for integrated and multidisciplinary management of patients, are considered as paradigms of quality care and have as one of the fundamental objectives to correct perioperative anemia. PBM has been incorporated into the schemes for intensified recovery of surgical patients: the recent Enhanced Recovery After Surgery 2021 pathway (in Spanish RICA 2021) includes almost 30 indirect recommendations for PBM. OBJECTIVE: To make a consensus document with RAND/UCLA Delphi methodology to increase the penetration and priority of the RICA 2021 recommendations on PBM in daily clinical practice. MATERIAL AND METHODS: A coordinating group composed of 6 specialists from Hematology-Hemotherapy, Anesthesiology and Internal Medicine with expertise in anemia and PBM was formed. A survey was elaborated using Delphi RAND/UCLA methodology to reach a consensus on the key areas and priority professional actions to be developed at the present time to improve the management of perioperative anemia. The survey questions were extracted from the PBM recommendations contained in the RICA 2021 pathway. The development of the electronic survey (Google Platform) and the management of the responses was the responsibility of an expert in quality of care and clinical safety. Participants were selected by invitation from speakers at AWGE-GIEMSA scientific meetings and national representatives of PBM-related working groups (Seville Document, SEDAR HTF section and RICA 2021 pathway participants). In the first round of the survey, the anonymized online questionnaire had 28 questions: 20 of them were about PBM concepts included in ERAS guidelines (2 about general PBM organization, 10 on diagnosis and treatment of preoperative anemia, 3 on management of postoperative anemia, 5 on transfusion criteria) and 8 on pending aspects of research. Responses were organized according to a 10-point Likter scale (0: strongly disagree to 10: strongly agree). Any additional contributions that the participants considered appropriate were allowed. They were considered consensual because all the questions obtained an average score of more than 9 points, except one (question 14). The second round of the survey consisted of 37 questions, resulting from the reformulation of the questions of the first round and the incorporation of the participants' comments. It consisted of 2 questions about general organization of PBM programme, 15 questions on the diagnosis and treatment of preoperative anemia; 3 on the management of postoperative anemia, 6 on transfusional criteria and finally 11 questions on aspects pending od future investigations. Statistical treatment: tabulation of mean, median and interquartiles 25-75 of the value of each survey question (Tables 1, 2 and 3). RESULTS: Except for one, all the recommendations were accepted. Except for three, all above 8, and most with an average score of 9 or higher. They are grouped into: 1.- "It is important and necessary to detect and etiologically diagnose any preoperative anemia state in ALL patients who are candidates for surgical procedures with potential bleeding risk, including pregnant patients". 2.- "The preoperative treatment of anemia should be initiated sufficiently in advance and with all the necessary hematinic contributions to correct this condition". 3.- "There is NO justification for transfusing any unit of packed red blood cells preoperatively in stable patients with moderate anemia Hb 8-10g/dL who are candidates for potentially bleeding surgery that cannot be delayed." 4.- "It is recommended to universalize restrictive criteria for red blood cell transfusion in surgical and obstetric patients." 5.- "Postoperative anemia should be treated to improve postoperative results and accelerate postoperative recovery in the short and medium term". CONCLUSIONS: There was a large consensus, with maximum acceptance,strong level of evidence and high recommendation in most of the questions asked. Our work helps to identify initiatives and performances who can be suitables for the implementation of PBM programs at each hospital and for all patients.


Assuntos
Anemia , Técnica Delphi , Procedimentos Cirúrgicos Eletivos , Humanos , Anemia/terapia , Transfusão de Sangue , Assistência Perioperatória/métodos , Assistência Perioperatória/normas , Complicações Pós-Operatórias/terapia , Complicações Pós-Operatórias/epidemiologia , Recuperação Pós-Cirúrgica Melhorada/normas
13.
Neurochirurgie ; 68(6): 684-687, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35461815

RESUMO

Cardiopulmonary complications are infrequent in patients with ventriculoatrial shunts (VAS). We report the case of an 18-year-old man with congenital hydrocephalus who developed pulmonary arterial hypertension (PAH) in the long-term follow-up after a VAS procedure. He presented with progressive exertional dyspnea, stabbing chest pain and acral cyanosis. Echocardiography showed severe PAH and a digitiform mass adhered to the distal catheter. A ventilation/perfusion scan suggested chronic pulmonary embolisms. Anticoagulation with intravenous heparin was started and thrombus resolution was achieved, but PAH remained. It is necessary to bear in mind complications linked to VAS when treating a patient with this device.


Assuntos
Hidrocefalia , Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Embolia Pulmonar , Masculino , Humanos , Adolescente , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Hidrocefalia/etiologia , Hipertensão Pulmonar/etiologia
14.
Clin Kidney J ; 15(3): 452-472, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35211303

RESUMO

BACKGROUND: Data on renal replacement therapy (RRT) for end-stage renal disease were collected by the European Renal Association (ERA) Registry via national and regional renal registries in Europe and countries bordering the Mediterranean Sea. This article provides a summary of the 2019 ERA Registry Annual Report, including data from 34 countries and additional age comparisons. METHODS: Individual patient data for 2019 were provided by 35 registries and aggregated data by 17 registries. Using these data, the incidence and prevalence of RRT, the kidney transplantation activity and the survival probabilities were calculated. RESULTS: In 2019, a general population of 680.8 million people was covered by the ERA Registry. Overall, the incidence of RRT was 132 per million population (p.m.p.). Of these patients, 62% were men, 54% were ≥65 years of age and 21% had diabetes mellitus as primary renal disease (PRD), and 84% had haemodialysis (HD), 11% had peritoneal dialysis (PD) and 5% had pre-emptive kidney transplantation as an initial treatment modality. The overall prevalence of RRT on 31 December 2019 was 893 p.m.p., with 58% of patients on HD, 5% on PD and 37% living with a kidney transplant. The overall kidney transplant rate was 35 p.m.p. and 29% of the kidney grafts were from a living donor. The unadjusted 5-year survival probability was 42.3% for patients commencing dialysis, 86.6% for recipients of deceased donor grafts and 94.4% for recipients of living donor grafts in the period 2010-14. When comparing age categories, there were substantial differences in the distribution of PRD, treatment modality and kidney donor type, and in the survival probabilities.

15.
Rev Esp Anestesiol Reanim (Engl Ed) ; 68(10): 555-563, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34844913

RESUMO

INTRODUCTION: anemia and iron deficiency predispose to an increased risk of transfusion with a consequent increase in morbidity and mortality. The study analyzes whether blood cell count parameters in addition to detecting anemia can predict iron deficiency and/or transfusional risk in patients undergoing mostly to scheduled primary hip and knee arthroplasty. OBJECTIVE: To analyze how blood cell count parameters predict iron deficiency and/or transfusional risk in patients undergoing programmed arthroplasty. MATERIAL AND METHODS: The analytical and transfusion results of 522 patients undergoing arthroplasty have been prospectively collected between 2013 and 2019 and the discriminative and predictive capacity of the basic parameters of the red cells have been analyzed; hemoglobin (Hb), mean cell volume, mean cell hemoglobin (HCM) and red blood cell distribution width (RDW) for the identification of presurgical iron deficiency and postsurgical transfusion. RESULTS: Anaemia was detected in 6.6%, "suboptim" Hb (<13 g/dL) in 14.5% and iron deficiency in 32.4%. Anemia detects only 13.8% of ID. After logistic regression analysis, the multivariate model significantly related Hb (p = .004), mean corpuscular hemoglobin (MCH) (p = .026), and the red cell distribution width (RDW) (p = .001) with ID; but mean corpuscular volume (MCV) is not significant. Hb, age and transferrin saturation index have been the only risk factors for transfusional risk of the parameters analyzed. CONCLUSIONS: The hemogram contains parameters that correlate with iron deficiency, however, mean cell volume, so widely used for the orientation of iron deficiency, is not valid as a discriminator of iron deficiency in this group of patients. Low Hb and transferrin saturation index are modifiable predictors for transfusion risk.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Transfusão de Sangue , Deficiências de Ferro , Contagem de Células Sanguíneas , Índices de Eritrócitos , Humanos , Ferro , Deficiências de Ferro/complicações
16.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34303541

RESUMO

INTRODUCTION: Anemia and iron deficiency predispose to an increased risk of transfusion with a consequent increase in morbidity and mortality. The study analyzes whether blood cell count parameters in addition to detecting anemia can predict iron deficiency and/or transfusional risk in patients undergoing mostly to scheduled primary hip and knee arthroplasty. OBJECTIVE: To analyze how blood cell count parameters predict iron deficiency and/or transfusional risk in patients undergoing programmed arthroplasty. MATERIAL AND METHODS: The analytical and transfusion results of 522 patients undergoing arthroplasty have been prospectively collected between 2013 and 2019 and the discriminative and predictive capacity of the basic parameters of the red cells have been analyzed; hemoglobin (Hb), mean cell volume, mean cell hemoglobin (HCM) and red blood cell distribution width (RDW) for the identification of presurgical iron deficiency and postsurgical transfusion. RESULTS: Anaemia was detected in 6.6%, "suboptim" Hb (<13g/dL) in 14.5% and iron deficiency in 32.4%. Anemia detects only 13.8% of ID. After logistic regression analysis, the multivariate model significantly related Hb (p=.004), mean corpuscular hemoglobin (MCH) (p=.026), and the red cell distribution width (RDW) (p=.001) with ID; but mean corpuscular volume (MCV) is not significant. Hb, age and transferrin saturation index have been the only risk factors for transfusional risk of the parameters analyzed. CONCLUSIONS: The hemogram contains parameters that correlate with iron deficiency, however, mean cell volume, so widely used for the orientation of iron deficiency, is not valid as a discriminator of iron deficiency in this group of patients. Low Hb and transferrin saturation index are modifiable predictors for transfusion risk.

17.
Hipertens Riesgo Vasc ; 37(3): 115-124, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-32534888

RESUMO

INTRODUCTION AND OBJECTIVES: Obesity and metabolic syndrome (MS) continue to be a problem at a socioeconomic level, causing high morbidity and mortality in the adult population. Prevention of risk factors should be carried out from an early age. Currently, there is no consensus on the opportune moment to start an intervention or treatment, regarding metabolic syndrome. The objective of the study is to describe the phenotype to predict early diagnosis of metabolic syndrome in schoolchildren. MATERIAL AND METHODS: Observational, prospective, cross-sectional and analytical study in schoolchildren from 6 to 15 years old, conducted in Guayaquil. Anthropometric measurements and a survey were performed, obtaining signing informed consent. The IBM Watson artificial intelligence (AI) platform with its software Modeler Flow, were used for the analysis. RESULTS: A population of 1025 students between 6 and 15 years old (mean of 12 years for men and 13 years for women) was examined, of whom 62.3% were men and 37.7% women. 23.9% of the population was overweight and 14% obese. A greater tendency to weight alteration was observed in men than in women (51.37% vs 47.79%), and a lower waist circumference in men (85 cm vs 87 cm, respectively). Males had a higher level of systolic blood pressure (SBP), being within the 90th percentile (mean SBP of 123 mmHg) 61.2%, compared to 38.8% of women, with a p < 0.001. Sedentary lifestyle is similar in both groups, with an average of 4.79 hours in front of the screen and/or video games. A statistically significant correlation was demonstrated between SBP and the waist/height ratio (WHtR) in the 90th percentile and 95th percentile (X2 9.075, p < 0.028, and X2 23,54, p < 0,000 respectively), as well as a relationship between 95th percentile and sex (X2 11.57, p < 0.001). The Modeler Flow software showed us that if WHtR, > 0.46, weight > 56.1 kg and height > 1.61 m, the probability of presenting metabolic syndrome, was of 82.4%. The statistic of this study has a predictive accuracy of 90% (error deviation of 0.009). The importance in the predictors of metabolic syndrome, range from 97.57% to 100%. CONCLUSIONS: A prevalence of 33.9% of metabolic syndrome was observed in schoolchildren from 6 to 15 years old, with pathological cut-off points of: WHtR > 0.46, weight > 56.1 kg, pure sedentary lifestyle > 3 hours in front of the screen/playing video games, and SBP within the 90th percentile (> 123 mmHg). With these four indicators, we can predict a probability of early diagnosis of metabolic syndrome of 97% to 100%.


Assuntos
Síndrome Metabólica/epidemiologia , Obesidade Infantil/epidemiologia , Comportamento Sedentário , Adolescente , Antropometria , Inteligência Artificial , Criança , Estudos Transversais , Diagnóstico Precoce , Equador , Feminino , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Fenótipo , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
18.
Neuromuscul Disord ; 28(10): 881-884, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30172469

RESUMO

Congenital myasthenic syndromes are a group of genetically determined rare diseases resulting from ultrastructural alterations in synaptic proteins. Up to 32 genes are known to be involved in those syndromes and many mutations have been reported, of which less than 8% affect the presynaptic complex. One of these syndromes is caused by the impairment of the presynaptic sodium-dependent high-affinity choline transporter 1, as a result of a mutation of the SCL5A7 gene associated with congenital myasthenic syndrome type 20 (MIM # 617143). We present a new case of this syndrome, caused by a mutation not previously described. A full term infant presented with acute respiratory failure and generalized weakness. The genetic analysis revealed the patient to be compound heterozygous for a new mutation of the SCL5A7 gene. The genetic analysis of congenital myasthenic syndromes provide information on the ultrastructural underlying mechanisms, which is valuable for differential diagnosis and specific treatments.


Assuntos
Mutação , Síndromes Miastênicas Congênitas/genética , Simportadores/genética , Diagnóstico Diferencial , Humanos , Recém-Nascido , Masculino , Debilidade Muscular/diagnóstico , Debilidade Muscular/genética , Debilidade Muscular/fisiopatologia , Debilidade Muscular/terapia , Síndromes Miastênicas Congênitas/diagnóstico , Síndromes Miastênicas Congênitas/fisiopatologia , Síndromes Miastênicas Congênitas/terapia , Fenótipo , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/genética , Insuficiência Respiratória/fisiopatologia , Insuficiência Respiratória/terapia
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