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1.
EMBO J ; 40(19): e108041, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34431536

RESUMO

The role of WNT/ß-catenin signalling in mouse neocortex development remains ambiguous. Most studies demonstrate that WNT/ß-catenin regulates progenitor self-renewal but others suggest it can also promote differentiation. Here we explore the role of WNT/STOP signalling, which stabilizes proteins during G2/M by inhibiting glycogen synthase kinase (GSK3)-mediated protein degradation. We show that mice mutant for cyclin Y and cyclin Y-like 1 (Ccny/l1), key regulators of WNT/STOP signalling, display reduced neurogenesis in the developing neocortex. Specifically, basal progenitors, which exhibit delayed cell cycle progression, were drastically decreased. Ccny/l1-deficient apical progenitors show reduced asymmetric division due to an increase in apical-basal astral microtubules. We identify the neurogenic transcription factors Sox4 and Sox11 as direct GSK3 targets that are stabilized by WNT/STOP signalling in basal progenitors during mitosis and that promote neuron generation. Our work reveals that WNT/STOP signalling drives cortical neurogenesis and identifies mitosis as a critical phase for neural progenitor fate.


Assuntos
Mitose , Neocórtex/embriologia , Neocórtex/metabolismo , Neurogênese , Via de Sinalização Wnt , Sequência de Aminoácidos , Animais , Biomarcadores , Ciclo Celular , Diferenciação Celular/genética , Ciclinas/genética , Ciclinas/metabolismo , Embrião de Mamíferos , Imunofluorescência , Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Mitose/genética , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Fosforilação , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo
2.
Genes Dev ; 30(12): 1389-94, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27313319

RESUMO

Adrenal glands are zonated endocrine organs that are essential in controlling body homeostasis. How zonation is induced and maintained and how renewal of the adrenal cortex is ensured remain a mystery. Here we show that capsular RSPO3 signals to the underlying steroidogenic compartment to induce ß-catenin signaling and imprint glomerulosa cell fate. Deletion of RSPO3 leads to loss of SHH signaling and impaired organ growth. Importantly, Rspo3 function remains essential in adult life to ensure replenishment of lost cells and maintain the properties of the zona glomerulosa. Thus, the adrenal capsule acts as a central signaling center that ensures replacement of damaged cells and is required to maintain zonation throughout life.


Assuntos
Córtex Suprarrenal/fisiologia , Diferenciação Celular/genética , Transdução de Sinais/genética , Trombospondinas/metabolismo , Córtex Suprarrenal/citologia , Animais , Proliferação de Células , Embrião de Mamíferos , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento/genética , Homeostase/genética , Masculino , Camundongos , Trombospondinas/genética , Zona Glomerulosa/citologia , Zona Glomerulosa/metabolismo , beta Catenina/metabolismo
3.
Haematologica ; 108(10): 2774-2782, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078253

RESUMO

Belantamab mafodotin (BM) is an anti-BCMA antibody-drug conjugate (GSK2857916) that represents an alternative option in multiple myeloma. We sought to assess the efficacy and safety of BM in a real-world setting in patients who benefited from an early access program. We conducted an observational, retrospective, multicenter study. Eligibility criteria were treatment of relapsed or refractory multiple myeloma (RRMM) in monotherapy in adult patients who have received at least three lines of therapy previously, including at least one immunomodulatory agent (IMiD), a proteasome inhibitor (PI) and an anti-CD38 monoclonal antibody, and whose disease progressed during the last treatment period. The primary endpoint of the study is to assess the overall survival (OS). Between November 2019 and December 2020, 106 patients were treated with BM; 97 were eligible for the efficacy evaluation and 104 for safety. The median age was 66 (range, 37-82) years. High-risk cytogenetics were identified in 40.9% of patients. Fifty-five (56.7%) patients were triple-class refractory and 11 (11.3%) were penta-class refractory. The median number of prior lines of treatment was five (range, 3-12). The median number of BM cycles administered was three (range, 1-22). The overall response rate at best response was 38.1% (37/97). The median OS was 9.3 months (95% confidence interval [CI]: 5.9-15.3), and median progression-free survival was 3.5 months (95% CI: 1.9-4.7). The median duration of response was 9 months (range, 4.65-10.4). Treatment was delayed for 55 (52.9%) patients including 36.5% for treatment-related toxicity. Ophthalmic adverse events, mainly grade ≤2, were the most common toxicity (48%). The occurrence of keratopathy was 37.5%. Overall, our data are concordant with the results from DREAMM-2 in terms of efficacy and safety on a non-biased population.


Assuntos
Mieloma Múltiplo , Adulto , Humanos , Idoso , Mieloma Múltiplo/tratamento farmacológico , Resultado do Tratamento , Estudos Retrospectivos , França
4.
Proc Natl Acad Sci U S A ; 117(49): 31278-31289, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229591

RESUMO

Presbycusis, or age-related hearing loss (ARHL), is a major public health issue. About half the phenotypic variance has been attributed to genetic factors. Here, we assessed the contribution to presbycusis of ultrarare pathogenic variants, considered indicative of Mendelian forms. We focused on severe presbycusis without environmental or comorbidity risk factors and studied multiplex family age-related hearing loss (mARHL) and simplex/sporadic age-related hearing loss (sARHL) cases and controls with normal hearing by whole-exome sequencing. Ultrarare variants (allele frequency [AF] < 0.0001) of 35 genes responsible for autosomal dominant early-onset forms of deafness, predicted to be pathogenic, were detected in 25.7% of mARHL and 22.7% of sARHL cases vs. 7.5% of controls (P = 0.001); half were previously unknown (AF < 0.000002). MYO6, MYO7A, PTPRQ, and TECTA variants were present in 8.9% of ARHL cases but less than 1% of controls. Evidence for a causal role of variants in presbycusis was provided by pathogenicity prediction programs, documented haploinsufficiency, three-dimensional structure/function analyses, cell biology experiments, and reported early effects. We also established Tmc1N321I/+ mice, carrying the TMC1:p.(Asn327Ile) variant detected in an mARHL case, as a mouse model for a monogenic form of presbycusis. Deafness gene variants can thus result in a continuum of auditory phenotypes. Our findings demonstrate that the genetics of presbycusis is shaped by not only well-studied polygenic risk factors of small effect size revealed by common variants but also, ultrarare variants likely resulting in monogenic forms, thereby paving the way for treatment with emerging inner ear gene therapy.


Assuntos
Surdez/genética , Genes Dominantes , Mutação/genética , Presbiacusia/genética , Fatores Etários , Idade de Início , Animais , Estudos de Casos e Controles , Estudos de Coortes , Heterozigoto , Humanos , Proteínas de Membrana/genética , Camundongos , MicroRNAs/genética , Mitocôndrias/genética , Sequenciamento do Exoma
5.
Emerg Infect Dis ; 26(9)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32819454

RESUMO

Nine new human invasive infections caused by the keratinophilic fungi Nannizziopsis obscura have been reported in France since 2004. The patients had variable clinical manifestations, had frequent dissemination, were mainly T-cell immunocompromised, and all originated from sub-Saharan West Africa. Before collection of the isolates, the etiologies of these infections were often misidentified, underscoring the extent of microscopic and cultural polymorphisms. All isolates but 1 had low MICs for the 8 antifungal drugs tested. When treated, patients received mainly azole therapy. Two of 7 patients with a known outcome died. We performed multilocus sequence analysis of N. obscura clinical strains and several strains of Nannizziopsis spp. isolated from reptiles. The human strains were clearly differentiated from the animal strains. N. obscura might be endemic to West Africa and responsible for undetected infections, which might become reactivated when immunosuppression occurs. N. obscura infection is probably underestimated because only sequencing enables proper identification.


Assuntos
Antifúngicos , África Subsaariana , África Ocidental/epidemiologia , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , França/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Onygenales
6.
Phys Rev Lett ; 124(22): 224502, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32567916

RESUMO

This Letter focuses on the dynamics of a liquid jet impacting the surface of a confined, immersed granular bed. Although previous works have considered the erosion process and surface morphology, less attention has been given to the jet hydrodynamics. Based on laboratory experiments, we show that when the liquid jet forms a crater, two situations arise. For weak or no erosion and for open craters, the jet is stationary. For vertical or overhanging crater walls, the jet displays a wide range of behaviors, from quasiperiodic oscillations to symmetry breaking and exploration of different states in time. An analysis of the different system states leads to the emergence of a bifurcation diagram depending on a dimensionless parameter, J, comparing the jet impact force to the force necessary to eject a grain. The frequency of the jet oscillations depends on the inertial velocity, the jet dispersion and the ratio between the injector cross section and the confinement length.

7.
Int J Audiol ; 59(2): 153-160, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31584300

RESUMO

Objective: This study evaluated the outcomes of the Oticon Medical Neuro Zti cochlear implant and the Neuro 2 sound processor.Design: Neuro One users were upgraded to Neuro 2. Monosyllabic word identification was evaluated in adults with Neuro One after ≥5 months, with Neuro 2 at upgrade, and with Neuro 2 after 3 months. Self-reported listening ability, satisfaction, and usability were measured in adults and children.Study sample: Participants were 44 adults and 26 children.Results: Speech identification scores in quiet and noise were 58% and 45% with Neuro One and 67% and 55% with Neuro 2 after 3 months, respectively. Hearing impairment duration and number of active electrodes significantly predicted speech identification in noise with Neuro 2. Significantly higher questionnaire ratings were obtained for Neuro 2 than Neuro One regarding listening ability in complex listening situations, comfort and music, as well as nine aspects of satisfaction and usability.Conclusion: This study demonstrates the clinical superiority of the Neuro 2 sound processor over Neuro One in terms of speech identification in quiet and in noise and reported patient benefit and satisfaction. Given the study design, sources of improvement may include factors unrelated to the sound processor itself.


Assuntos
Implante Coclear/instrumentação , Implantes Cocleares , Perda Auditiva/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , França , Perda Auditiva/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Ruído , Satisfação do Paciente , Percepção da Fala , Teste do Limiar de Recepção da Fala , Resultado do Tratamento , Adulto Jovem
8.
Dev Biol ; 441(1): 42-51, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29859889

RESUMO

Coronary artery anomalies are common congenital disorders with serious consequences in adult life. Coronary circulation begins when the coronary stems form connections between the aorta and the developing vascular plexus. We recently identified the WNT signaling modulator R-spondin 3 (Rspo3), as a crucial regulator of coronary stem proliferation. Using expression analysis and tissue-specific deletion we now demonstrate that Rspo3 is primarily produced by cardiomyocytes. Moreover, we have employed CRISPR/Cas9 technology to generate novel Lgr4-null alleles that showed a significant decrease in coronary stem proliferation and thus phenocopied the coronary artery defects seen in Rspo3 mutants. Interestingly, Lgr4 mutants displayed slightly hypomorphic right ventricles, an observation also made after myocardial specific deletion of Rspo3. These results shed new light on the role of Rspo3 in heart development and demonstrate that LGR4 is the principal R-spondin 3 receptor in the heart.


Assuntos
Vasos Coronários/embriologia , Coração/embriologia , Miócitos Cardíacos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Trombospondinas/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Circulação Coronária/fisiologia , Vasos Coronários/citologia , Camundongos , Camundongos Transgênicos , Miócitos Cardíacos/citologia , Receptores Acoplados a Proteínas G/genética , Trombospondinas/genética
9.
Am J Otolaryngol ; 38(6): 713-717, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28864273

RESUMO

We report the first case of a transtympanic iatrogenic internal carotid artery (ICA) pseudoaneurysm diagnosed in a 4-year-old child following a myringotomy. An endovascular treatment with a covered-stent was decided; spontaneous thrombosis was found during the therapeutic arteriography, and the procedure was aborted. Otoscopy and computed tomography (CT) scan monitoring showed a prolonged thrombosis and the disappearance of the pseudoaneurysm 18months after the diagnostic arteriography. Based on literature review, endovascular techniques seem to be preferred to the surgical approach for treatment of intrapetrous ICA pseudoaneurysm, however clinical and CT scan monitoring may also be a valid option.


Assuntos
Falso Aneurisma/etiologia , Doenças das Artérias Carótidas/etiologia , Artéria Carótida Interna , Perda Auditiva Condutiva/etiologia , Ventilação da Orelha Média/efeitos adversos , Otite Média/cirurgia , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/cirurgia , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/cirurgia , Pré-Escolar , Perda Auditiva Condutiva/diagnóstico por imagem , Perda Auditiva Condutiva/cirurgia , Humanos , Masculino , Otite Média/complicações , Otite Média/diagnóstico por imagem
10.
Hum Mol Genet ; 23(9): 2440-6, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24334767

RESUMO

Malignant pheochromocytoma (PCC) and paraganglioma (PGL) are mostly caused by germline mutations of SDHB, encoding a subunit of succinate dehydrogenase. Using whole-exome sequencing, we recently identified a mutation in the FH gene encoding fumarate hydratase, in a PCC with an 'SDH-like' molecular phenotype. Here, we investigated the role of FH in PCC/PGL predisposition, by screening for germline FH mutations in a large international cohort of patients. We screened 598 patients with PCC/PGL without mutations in known PCC/PGL susceptibility genes. We searched for FH germline mutations and large deletions, by direct sequencing and multiplex ligation-dependent probe amplification methods. Global alterations in DNA methylation and protein succination were assessed by immunohistochemical staining for 5-hydroxymethylcytosine (5-hmC) and S-(2-succinyl) cysteine (2SC), respectively. We identified five pathogenic germline FH mutations (four missense and one splice mutation) in five patients. Somatic inactivation of the second allele, resulting in a loss of fumarate hydratase activity, was demonstrated in tumors with FH mutations. Low tumor levels of 5-hmC, resembling those in SDHB-deficient tumors, and positive 2SC staining were detected in tumors with FH mutations. Clinically, metastatic phenotype (P = 0.007) and multiple tumors (P = 0.02) were significantly more frequent in patients with FH mutations than those without such mutations. This study reveals a new role for FH in susceptibility to malignant and/or multiple PCC/PGL. Remarkably, FH-deficient PCC/PGLs display the same pattern of epigenetic deregulation as SDHB-mutated malignant PCC/PGL. Therefore, we propose that mutation screening for FH should be included in PCC/PGL genetic testing, at least for tumors with malignant behavior.


Assuntos
Fumarato Hidratase/genética , Mutação em Linhagem Germinativa/genética , Paraganglioma/genética , Feocromocitoma/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Éxons/genética , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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