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1.
Br J Haematol ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802081

RESUMO

Few studies have used validated scales to assess the intensity and determinants of fatigue, a major symptom of sickle cell disease (SCD). We aimed to assess the level of basal fatigue in adult patients with SCD, using the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) questionnaire. We prospectively included 102 stable adult outpatients with SCD over 2 months, who answered the FACIT-Fatigue (ranging from 0 (worst imaginable fatigue) to 52 (no fatigue)) and reported on the intensity of fatigue and its impact on quality of life. The cut-off for significant fatigue was <34. The median [IQR] FACIT-Fatigue score was 29 [22-37], indicating moderate-to-severe fatigue. In a multivariate analysis, the FACIT-Fatigue score was significantly associated with female sex, high body mass index, high level of stress, poor sleep quality, and number of previous episodes of acute chest syndrome, but not with the genotype or the haemoglobin level. Most adult patients with SCD experience significant and sometimes intense fatigue; this is probably due to several factors, including disease activity. Fatigue should be evaluated systematically during consultations and in patient education programmes and as an end-point in therapeutic trials.

2.
Am J Hematol ; 99(6): 1108-1118, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563187

RESUMO

We investigated using a custom NGS panel of 149 genes the mutational landscape of 64 consecutive adult patients with tyrosine kinase fusion-negative hypereosinophilia (HE)/hypereosinophilic syndrome (HES) harboring features suggestive of myeloid neoplasm. At least one mutation was reported in 50/64 (78%) patients (compared to 8/44 (18%) patients with idiopathic HE/HES/HEUS used as controls; p < .001). Thirty-five patients (54%) had at least one mutation involving the JAK-STAT pathway, including STAT5B (n = 18, among which the hotspot N642H, n = 13), JAK1 (indels in exon 13, n = 5; V658F/L, n = 2), and JAK2 (V617F, n = 6; indels in exon 13, n = 2). Other previously undescribed somatic mutations were also found in JAK2, JAK1, STAT5B, and STAT5A, including three patients who shared the same STAT5A V707fs mutation and features consistent with primary polycythemia. Nearly all JAK-STAT mutations were preceded by (or associated with) myelodysplasia-related gene mutations, especially in RNA-splicing genes or chromatin modifiers. In multivariate analysis, neurologic involvement (hazard ratio [HR] 4.95 [1.87-13.13]; p = .001), anemia (HR 5.50 [2.24-13.49]; p < .001), and the presence of a high-risk mutation (as per the molecular international prognosis scoring system: HR 6.87 [2.39-19.72]; p < .001) were independently associated with impaired overall survival. While corticosteroids were ineffective in all treated JAK-STAT-mutated patients, ruxolitinib showed positive hematological responses including in STAT5A-mutated patients. These findings emphasize the usefulness of NGS for the workup of tyrosine kinase fusion-negative HE/HES patients and support the use of JAK inhibitors in this setting. Updated classifications could consider patients with JAK-STAT mutations and eosinophilia as a new "gene mutated-entity" that could be differentiated from CEL, NOS, and idiopathic HES.


Assuntos
Síndrome Hipereosinofílica , Mutação , Fator de Transcrição STAT5 , Humanos , Síndrome Hipereosinofílica/genética , Síndrome Hipereosinofílica/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Fator de Transcrição STAT5/genética , Janus Quinase 2/genética , Transdução de Sinais , Janus Quinase 1/genética , Idoso de 80 Anos ou mais , Pirimidinas/uso terapêutico , Adulto Jovem
3.
Artigo em Inglês | MEDLINE | ID: mdl-38597601

RESUMO

Epitaxial growth of WTe2 offers significant advantages, including the production of high-quality films, possible long-range in-plane ordering, and precise control over layer thicknesses. However, the mean island size of WTe2 grown by molecular beam epitaxy (MBE) in the literature is only a few tens of nanometers, which is not suitable for the implementation of devices at large lateral scales. Here we report the growth of Td -WTe2 ultrathin films by MBE on monolayer (ML) graphene, reaching a mean flake size of ≃110 nm, which is, on overage, more than three times larger than previous results. WTe2 films thicker than 5 nm have been successfully synthesized and exhibit the expected Td phase atomic structure. We rationalize the epitaxial growth of Td-WTe2 and propose a simple model to estimate the mean flake size as a function of growth parameters that can be applied to other transition metal dichalcogenides (TMDCs). Based on nucleation theory and the Kolmogorov-Johnson-Meh-Avrami (KJMA) equation, our analytical model supports experimental data showing a critical coverage of 0.13 ML above which WTe2 nucleation becomes negligible. The quality of monolayer WTe2 films is demonstrated by electronic band structure analysis using angle-resolved photoemission spectroscopy (ARPES), which is in agreement with first-principles calculations performed on free-standing WTe2 and previous reports. We found electron pockets at the Fermi level, indicating a n-type doping of WTe2 with an electron density of n = 2.0 ± 0.5 × 1012 cm-2 for each electron pocket.

4.
Retina ; 44(3): 506-514, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37948742

RESUMO

PURPOSE: The primary aim was to describe the patterns of paramacular involvement, not yet reported but that optical coherence tomography angiography can now detect in patients with sickle cell disease. The secondary aim was to search arguments concerning the physiopathogeny of paramacular involvement. METHODS: This institutional cohort retrospective study was conducted in a Referral Center for Ophthalmological Rare Diseases. Follow-up included an ophthalmologic examination with optical coherent tomography and optical coherent tomography angiography. RESULTS: One hundred and thirty-two patients with SCD were included. Typical sickle cell maculopathy was observed in temporal area in 84 eyes (40.0%) of SS patients and eight eyes (14.8%) of SC patients ( P < 0.001). Enlargement of the foveal avascular zone was observed in 10 eyes of eight SS patients. Two atypical parafoveal abnormalities were found in SS patients only. The first one consisted of macular thinning with normal vascularization in 15 eyes of 11 patients. The second atypical maculopathy was large areas of loss of vascularization without retinal thinning 10 eyes of six patients. Multivariate analysis did not show a statistically significant relation between the peripheral sickle retinopathy stage and the different type of sickle cell maculopathy ( P = 0.21). CONCLUSION: Those atypical sickle cell maculopathy may correspond to early forms preceding a typical sickle cell disease maculopathy (SCDM). This would point toward several physiopathogenic mechanisms. The first one included the existence of ischemia that can be related to anemia. Presence of retinal thinning without vascular involvement point out to a neurogenic mechanism.


Assuntos
Anemia Falciforme , Degeneração Macular , Doenças Retinianas , Humanos , Estudos Retrospectivos , Angiofluoresceinografia/métodos , Acuidade Visual , Doenças Retinianas/diagnóstico , Doenças Retinianas/etiologia , Doenças Retinianas/patologia , Anemia Falciforme/complicações , Anemia Falciforme/diagnóstico , Tomografia de Coerência Óptica/métodos , Degeneração Macular/complicações , Vasos Retinianos/patologia
5.
Front Med (Lausanne) ; 10: 1226210, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37700770

RESUMO

Purpose: To identify risk factors for sickle cell maculopathy due to hematological parameters (especially anemia and hemolysis) or cerebral vasculopathy. Methods: This retrospective study was conducted at a Referral Center. The follow-up included optical coherent tomography/optical coherent tomography angiography, neuro-radiological imaging, and a hematological assessment (hemoglobin, hemoglobin S level, reticulocytes, mean corpuscular volume, bilirubin, and lactate dehydrogenase). Results: Hundred and thirty-two sickle cell patients were included. Maculopathy was observed in 127 eyes of SS patients and 10 eyes of SC patients (p < 0.001), unrelated to peripheral retinopathy. Cerebral vasculopathy was more frequent in SS patients (p < 0.001) and was also associated with the presence of maculopathy (p = 0.049), and it was related to peripheral retinopathy (p < 0.001). All biological parameters significantly differed according to the genotype (p < 0.001) but not according to the presence of cerebral vasculopathy or maculopathy. In the multivariate analysis, reticulocytes and bilirubin were associated with the presence of cerebral vasculopathy and maculopathy. Conclusion: The data obtained were consistent with the role of anemia or hemolysis markers in cerebral vasculopathy and macular involvement. As a trend of hemolysis appears to be a risk factor for these complications, this validates the use of preventive plasmapheresis in these patients.

6.
Adv Mater ; 35(41): e2306312, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37615204

RESUMO

The study of moiré engineering started with the advent of van der Waals heterostructures, in which stacking 2D layers with different lattice constants leads to a moiré pattern controlling their electronic properties. The field entered a new era when it was found that adjusting the twist between two graphene layers led to strongly-correlated-electron physics and topological effects associated with atomic relaxation. A twist is now routinely used to adjust the properties of 2D materials. This study investigates a new type of moiré superlattice in bilayer graphene when one layer is biaxially strained with respect to the other-so-called biaxial heterostrain. Scanning tunneling microscopy measurements uncover spiraling electronic states associated with a novel symmetry-breaking atomic reconstruction at small biaxial heterostrain. Atomistic calculations using experimental parameters as inputs reveal that a giant atomic swirl forms around regions of aligned stacking to reduce the mechanical energy of the bilayer. Tight-binding calculations performed on the relaxed structure show that the observed electronic states decorate spiraling domain wall solitons as required by topology. This study establishes biaxial heterostrain as an important parameter to be harnessed for the next step of moiré engineering in van der Waals multilayers.

7.
Ther Adv Respir Dis ; 17: 17534666231178690, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37329289

RESUMO

We present a case report of transbronchial cryobiopsy proven diffuse amyloid cystic lung disease complicating a homozygous Val122Ile (V122I) transthyretin mutated amyloidosis (ATTRm). To the best of our knowledge, this is the first case in the literature reporting such pulmonary lesions in ATTRm amyloidosis, and notably diagnosed through cryobiopsy. A 51-year-old man from Mali with a past medical history of bilateral carpal tunnel syndrome presented erectile dysfunction, asthenia and worsening dyspnoea over the past year. He presented signs of cardiac failure; histological and radiological investigations diagnosed cardiac amyloidosis. He was found homozygote for the V122I mutation in transthyretin. A diffuse cystic lung disease (DCLD) was noted on computed tomography (CT) scan. We performed a transbronchial pulmonary cryobiopsy that revealed histological transthyretin amyloid deposits. This case report illustrates the safety and usefulness of cryobiopsy in the setting of DCLD and extends ATTRm amyloidosis as a possible cause of DCLD.


Assuntos
Amiloidose , Insuficiência Cardíaca , Pneumopatias , Masculino , Humanos , Pessoa de Meia-Idade , Pré-Albumina/genética , Amiloidose/diagnóstico , Amiloidose/genética , Mutação
9.
Sci Rep ; 13(1): 5426, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37012307

RESUMO

We build new material descriptors to predict the band gap and the work function of 2D materials by tree-based machine-learning models. The descriptor's construction is based on vectorizing property matrices and on empirical property function, leading to mixing features that require low-resource computations. Combined with database-based features, the mixing features significantly improve the training and prediction of the models. We find R[Formula: see text] greater than 0.9 and mean absolute errors (MAE) smaller than 0.23 eV both for the training and prediction. The highest R[Formula: see text] of 0.95, 0.98 and the smallest MAE of 0.16 eV and 0.10 eV were obtained by using extreme gradient boosting for the bandgap and work-function predictions, respectively. These metrics were greatly improved as compared to those of database features-based predictions. We also find that the hybrid features slightly reduce the overfitting despite a small scale of the dataset. The relevance of the descriptor-based method was assessed by predicting and comparing the electronic properties of several 2D materials belonging to new classes (oxides, nitrides, carbides) with those of conventional computations. Our work provides a guideline to efficiently engineer descriptors by using vectorized property matrices and hybrid features for predicting 2D materials properties via ensemble models.

10.
Br J Haematol ; 201(6): 1229-1238, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36965115

RESUMO

Data on acute chest syndrome (ACS) in adult sickle cell disease patients are scarce. In this study, we describe 105 consecutive ACS episodes in 81 adult patients during a 32-month period and compare the characteristics as a function of the time to onset after hospital admission for a vaso-occlusive crisis (VOC), that is early-onset episodes (time to onset ≤24 h, 42%) versus secondary episodes (>24 h, 58%; median [interquartile range] time to onset: 2 [2-3] days). The median age was 27 [22-34] years, 89% of the patients had an S/S or S/ß0 -thalassaemia genotype; 81% of the patients had a history of ACS (median: 3 [2-5] per patient), only 61% were taking a disease-modifying treatment at the time of the ACS. Fever and chest pain were noted in respectively 54% and 73% of the episodes. Crackles (64%) and bronchial breathing (32%) were the main abnormal auscultatory findings. A positive microbiological test was found for 20% of episodes. Fifty percent of the episodes required a blood transfusion; ICU transfer and mortality rates were respectively 29% and 1%. Secondary and early-onset forms of ACS did not differ significantly. Disease-modifying treatments should be revaluated after each ACS episode because the recurrence rate is high.


Assuntos
Síndrome Torácica Aguda , Anemia Falciforme , Transtornos Respiratórios , Humanos , Adulto , Síndrome Torácica Aguda/complicações , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Hospitalização , Hospitais , Doença Aguda
11.
Nanotechnology ; 34(16)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36638530

RESUMO

By combining non-contact atomic force microscopy (nc-AFM) and Kelvin probe microscopy (KPFM) in ultra high vacuum environment (UHV), we directly measure the height and work function of graphene monolayer on the Si-face of 6H-SiC(0001) with a precision that allows us to differentiate three different types of graphene structures : zero layer graphene (ZLG), Quasi free-standing monolayer graphene (QFMLG) and bilayer graphene (BLG). The height and work function of ZLG are 2.62 ± 0.22 Å and 4.42 ± 0.05 eV respectively, when they are 4.09 ± 0.11 Å and 4.63 ± 0.05 eV for QFMLG. The work function is 4.83 ± 0.05 eV for the BLG. Unlike any other available technique, the local nc-AFM/KPFM dual probe makes it possible to directly identify the nature of nanometer-sized graphene islands that constitute the early nuclei of graphene monolayer grown on 6H-SiC(0001) by chemical vapor deposition.

12.
Materials (Basel) ; 15(23)2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500097

RESUMO

In this study, AlN epilayers were grown by ammonia-assisted molecular beam epitaxy on 3 nm h-BN grown on c-sapphire substrates. Their structural properties were investigated by comparing as-grown and postgrowth annealed layers. The role of annealing on the crystalline quality and surface morphology was studied as a function of AlN thickness and the annealing duration and temperature. Optimum annealing conditions were identified. The results of X-ray diffraction showed that optimization of the annealing recipe led to a significant reduction in the symmetric (0 0 0 2) and skew symmetric (1 0 -1 1) reflections, which was associated with a reduction in edge and mixed threading dislocation densities (TDDs). Furthermore, the impact on the crystalline structure of AlN and its surface was studied, and the results showed a transition from a surface with high roughness to a smoother surface morphology with a significant reduction in roughness. In addition, the annealing duration was increased at 1650 °C to further understand the impact on both AlN and h-BN, and the results showed a diffusion interplay between AlN and h-BN. Finally, an AlN layer was regrown on the top of an annealed template, which led to large terraces with atomic steps and low roughness.

13.
ACS Nano ; 16(4): 5920-5931, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35294163

RESUMO

Graphene, consisting of an inert, thermally stable material with an atomically flat, dangling-bond-free surface, is by essence an ideal template layer for van der Waals heteroepitaxy of two-dimensional materials such as silicene. However, depending on the synthesis method and growth parameters, graphene (Gr) substrates could exhibit, on a single sample, various surface structures, thicknesses, defects, and step heights. These structures noticeably affect the growth mode of epitaxial layers, e.g., turning the layer-by-layer growth into the Volmer-Weber growth promoted by defect-assisted nucleation. In this work, the growth of silicon on chemical vapor deposited epitaxial Gr (1 ML Gr/1 ML Gr buffer) on a 6H-SiC(0001) substrate is investigated by a combination of atomic force microscopy (AFM), scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Raman spectroscopy measurements. It is shown that the perfect control of full-scale almost defect-free 1 ML Gr with a single surface structure and the ultraclean conditions for molecular beam epitaxy deposition of silicon represent key prerequisites for ensuring the growth of extended silicene sheets on epitaxial graphene. At low coverages, the deposition of Si produces large silicene sheets (some hundreds of nanometers large) attested by both AFM and SEM observations and the onset of a Raman peak at 560 cm-1, very close to the theoretical value of 570 cm-1 calculated for free-standing silicene. This vibrational mode at 560 cm-1 represents the highest ever experimentally measured value and is representative of quasi-free-standing silicene with almost no interaction with inert nonmetal substrates. From a coverage rate of 1 ML, the silicene sheets disappear at the expense of 3D Si dendritic islands whose density, size, and thickness increase with the deposited thickness. From this coverage, the Raman mode assigned to quasi-free-standing silicene totally vanishes, and the 2D flakes of silicene are no longer observed by AFM. The experimental results are in very good agreement with the results of kinetic Monte Carlo simulations that rationalize the initial flake growth in solid-state dewetting conditions, followed by the growth of ridges surrounding and eventually covering the 2D flakes. A full description of the growth mechanism is given. This study, which covers a wide range of growth parameters, challenges recent results stating the impossibility to grow silicene on a carbon inert surface and is very promising for large-scale silicene growth. It shows that silicene growth can be achieved using perfectly controlled and ultraclean deposition conditions and an almost defect-free Gr substrate.

14.
Brain Behav ; 12(2): e2455, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35040287

RESUMO

BACKGROUND: VZV infection can involve every level of the neurologic system: from the central nervous system (CNS) to the peripheral nervous system (PNS), including aseptic meningitis. Prognosis seems to differ between these neurological involvements. Prognostic factors remain unknown. METHODS: This is a retrospective multicenter study including all patients with a positive VZV polymerase chain reaction (PCR) in the cerebrospinal fluid (CSF) from eight centers in Paris (France) between 2011 and 2018. Unfavorable outcome was defined as mortality linked to VZV or incomplete recovery. Modified Rankin Scale (mRS) evaluated disability before and after the infection, with the difference designated as Rankin Delta. RESULTS: Seventy-two patients were included (53% male, median age 51 years, median mRS 0). Immunosuppression was reported in 42%. The clinical spectrum included 26 cases of meningitis, 27 instances of CNS involvement, 16 of PNS involvement, and 3 isolated replications (positive PCR but no criteria for neurological complications from VZV). Antiviral treatment was administered to 69 patients (96%). Sixty-two patients completed follow-up. Death linked to VZV occurred in eight cases. Unfavorable outcome (UO) occurred in 60% and was significantly associated with a higher prior mRS (Odd-ratio (OR) 3.1 [1.4-8.8] p = .012) and the presence of PNS or CNS manifestations (OR 22 [4-181] p = .001, OR 6.2 [1.3-33] p = .03, respectively, compared to meningitis). In the CSF, higher protein level (p < .0001) was also significantly associated with a higher Rankin Delta. CONCLUSIONS: Neurological complications of VZV with evidence of CSF viral replication are heterogeneous: aseptic meningitis has a good prognosis, whereas presence of CNS and PNS involvement is associated with a higher risk of mortality and of sequelae, respectively.


Assuntos
Encefalite por Varicela Zoster , Meningite Asséptica , Meningite , Líquido Cefalorraquidiano , Encefalite por Varicela Zoster/diagnóstico , Encefalite por Varicela Zoster/tratamento farmacológico , Feminino , Herpesvirus Humano 3/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos
15.
Lupus ; 30(3): 514-517, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33307985

RESUMO

Antiphospholipid syndrome (APS) is an acquired autoimmune disease characterized by recurrent venous or arterial thrombotic events and pregnancy morbidity, with persistently presence of antiphospholipid antibodies (aPL). We report three cases of central serous chorioretinopathy (CSC) associated with APS.


Assuntos
Síndrome Antifosfolipídica/complicações , Coriorretinopatia Serosa Central/etiologia , Adulto , Anticorpos Antifosfolipídeos/imunologia , Coriorretinopatia Serosa Central/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Intern Emerg Med ; 13(8): 1201-1209, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29951810

RESUMO

Extreme hypomagnesemia (hypoMg) can be encountered in many situations, but little data currently exist. Our aim is to describe the epidemiological, clinical, etiological characteristics, and the biological abnormalities of consecutive inpatients with extreme hypomagnesemia. In our observational monocentric study, between 1st July 2000 and April 2015, all inpatients with extreme hypomagnesemia, defined by at least one plasma magnesium concentration (PMg) below 0.3 mmol/L, were included. Demographic, clinical, biological characteristics and the drugs prescribed before the qualifying PMg measurement were retrospectively collected. 41,069 patients had at least one PMg assessment. The prevalence of extreme hypomagnesemia is 0.3% (119 inpatients). The median age is 70 years, 52% are women. The patients were mainly hospitalized in intensive care (n = 37, 31.1%), oncology (n = 21, 17.6%), gastroenterology (n = 18, 15.1%) and internal medicine (n = 16, 13.4%) departments. One hundred patients (84%) had a medical history of gastrointestinal disease (39% with bowel resections, 24% with stoma), and 50 (42%) had a cancer history. The drugs most commonly prescribed (known to induce hypoMg) are proton pump inhibitors (PPI) (n = 77, 70%), immunosuppressive regimens (n = 25, 22.5%), platinum salt-based chemotherapies (n = 19, 17.1%), and diuretics (n = 22, 19.8%). The suspected causes of hypomagnesemia are often multiple, but drugs (46%, including PPI in 19%) and chronic gastrointestinal disorders (37%) are prominent. Associated electrolyte disturbances include hypocalcemia (77%) and mild hypokalemia (51%). The 1-month mortality from all causes is 16%. Extreme hypomagnesemia is rare in inpatients, and is frequently associated with severe hypocalcemia. Digestive disorders and drugs are the main contributory causes.


Assuntos
Hipercalciúria/classificação , Hipercalciúria/etiologia , Magnésio/análise , Nefrocalcinose/classificação , Nefrocalcinose/etiologia , Erros Inatos do Transporte Tubular Renal/classificação , Erros Inatos do Transporte Tubular Renal/etiologia , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Diuréticos/efeitos adversos , Diuréticos/uso terapêutico , Feminino , França/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Hipercalciúria/epidemiologia , Magnésio/sangue , Magnésio/classificação , Masculino , Pessoa de Meia-Idade , Nefrocalcinose/epidemiologia , Prevalência , Inibidores da Bomba de Prótons/efeitos adversos , Inibidores da Bomba de Prótons/uso terapêutico , Erros Inatos do Transporte Tubular Renal/epidemiologia , Estudos Retrospectivos , Estatísticas não Paramétricas
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