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1.
EMBO J ; 40(19): e108041, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34431536

RESUMEN

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.


Asunto(s)
Mitosis , Neocórtex/embriología , Neocórtex/metabolismo , Neurogénesis , Vía de Señalización Wnt , Secuencia de Aminoácidos , Animales , Biomarcadores , Ciclo Celular , Diferenciación Celular/genética , Ciclinas/genética , Ciclinas/metabolismo , Embrión de Mamíferos , Técnica del Anticuerpo Fluorescente , Expresión Génica , Glucógeno Sintasa Quinasa 3/metabolismo , Inmunohistoquímica , Ratones , Ratones Noqueados , Mitosis/genética , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neurogénesis/genética , Fosforilación , Factores de Transcripción SOXC/genética , Factores de Transcripción SOXC/metabolismo
2.
Genes Dev ; 30(12): 1389-94, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27313319

RESUMEN

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.


Asunto(s)
Corteza Suprarrenal/fisiología , Diferenciación Celular/genética , Transducción de Señal/genética , Trombospondinas/metabolismo , Corteza Suprarrenal/citología , Animales , Proliferación Celular , Embrión de Mamíferos , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica/genética , Homeostasis/genética , Masculino , Ratones , Trombospondinas/genética , Zona Glomerular/citología , Zona Glomerular/metabolismo , beta Catenina/metabolismo
3.
Haematologica ; 108(10): 2774-2782, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37078253

RESUMEN

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.


Asunto(s)
Mieloma Múltiple , Adulto , Humanos , Anciano , Mieloma Múltiple/tratamiento farmacológico , Resultado del Tratamiento , Estudios Retrospectivos , Francia
4.
Proc Natl Acad Sci U S A ; 117(49): 31278-31289, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33229591

RESUMEN

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.


Asunto(s)
Sordera/genética , Genes Dominantes , Mutación/genética , Presbiacusia/genética , Factores de Edad , Edad de Inicio , Animales , Estudios de Casos y Controles , Estudios de Cohortes , Heterocigoto , Humanos , Proteínas de la Membrana/genética , Ratones , MicroARNs/genética , Mitocondrias/genética , Secuenciación del Exoma
5.
Emerg Infect Dis ; 26(9)2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32819454

RESUMEN

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.


Asunto(s)
Antifúngicos , África del Sur del Sahara , África Occidental/epidemiología , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Francia/epidemiología , Humanos , Pruebas de Sensibilidad Microbiana , Onygenales
6.
Phys Rev Lett ; 124(22): 224502, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32567916

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-31584300

RESUMEN

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.


Asunto(s)
Implantación Coclear/instrumentación , Implantes Cocleares , Pérdida Auditiva/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Francia , Pérdida Auditiva/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Ruido , Satisfacción del Paciente , Percepción del Habla , Prueba del Umbral de Recepción del Habla , Resultado del Tratamiento , Adulto Joven
8.
Dev Biol ; 441(1): 42-51, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29859889

RESUMEN

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.


Asunto(s)
Vasos Coronarios/embriología , Corazón/embriología , Miocitos Cardíacos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Trombospondinas/metabolismo , Vía de Señalización Wnt/fisiología , Animales , Circulación Coronaria/fisiología , Vasos Coronarios/citología , Ratones , Ratones Transgénicos , Miocitos Cardíacos/citología , Receptores Acoplados a Proteínas G/genética , Trombospondinas/genética
9.
Am J Otolaryngol ; 38(6): 713-717, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28864273

RESUMEN

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.


Asunto(s)
Aneurisma Falso/etiología , Enfermedades de las Arterias Carótidas/etiología , Arteria Carótida Interna , Pérdida Auditiva Conductiva/etiología , Ventilación del Oído Medio/efectos adversos , Otitis Media/cirugía , Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/cirugía , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/cirugía , Preescolar , Pérdida Auditiva Conductiva/diagnóstico por imagen , Pérdida Auditiva Conductiva/cirugía , Humanos , Masculino , Otitis Media/complicaciones , Otitis Media/diagnóstico por imagen
10.
Hum Mol Genet ; 23(9): 2440-6, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24334767

RESUMEN

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.


Asunto(s)
Fumarato Hidratasa/genética , Mutación de Línea Germinal/genética , Paraganglioma/genética , Feocromocitoma/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Exones/genética , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Eur Arch Otorhinolaryngol ; 273(7): 1689-96, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26205152

RESUMEN

The objective of this study is to report the surgical outcome after middle fossa approach (MFA) plugging in patients suffering from a superior semi-circular canal dehiscence (SCD) syndrome. This is a retrospective case review. Tertiary referral center. Sixteen ears in 13 patients with a SCD syndrome suffering from severe and disabling vestibular symptoms with a bony dehiscence on CT scan >3 mm and decreased threshold of cervical vestibular evoked potentials (cVEMPs). We assessed preoperatively: clinical symptoms, hearing, cVEMPs threshold, size of dehiscence and videonystagmography (VNG) with caloric and 100 Hz vibratory tests. Postoperatively, we noted occurrences of neurosurgical complication, evolution of audiological and vestibular symptoms, and evaluation of cVEMP data. Tullio's phenomenon was observed in 13 cases (81.3 %) and subjectively reported hearing loss in seven (43.7 %). All patients were so disabled that they had to stop working. No neurosurgical complications were observed in the postoperative course. In three cases (16.6 %), an ipsilateral and transitory immediate postoperative vestibular deficit associated with a sensorineural hearing loss (SNHL) was noted, which totally resolved with steroids and bed rest. All patients were relieved of audiological and vestibular symptoms and could return to normal activity with a mean follow-up of 31.1 months (range 3-95). No patient had residual SNHL. cVEMPs were performed in 14 ears postoperatively and were normalized in 12 (85.7 %). Two of the three patients operated on both sides kept some degree of unsteadiness and oscillopsia. MFA plugging of the superior semi-circular canal is an efficient and non-hearing deteriorating procedure.


Asunto(s)
Pérdida Auditiva Sensorineural , Procedimientos Quirúrgicos Otológicos , Complicaciones Posoperatorias , Canales Semicirculares , Vestíbulo del Laberinto , Adulto , Audiometría/métodos , Femenino , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/etiología , Humanos , Masculino , Persona de Mediana Edad , Nistagmo Patológico/diagnóstico , Nistagmo Patológico/etiología , Procedimientos Quirúrgicos Otológicos/efectos adversos , Procedimientos Quirúrgicos Otológicos/instrumentación , Procedimientos Quirúrgicos Otológicos/métodos , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Canales Semicirculares/patología , Canales Semicirculares/cirugía , Instrumentos Quirúrgicos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Enfermedades Vestibulares/diagnóstico , Enfermedades Vestibulares/etiología , Enfermedades Vestibulares/cirugía , Pruebas de Función Vestibular/métodos , Vestíbulo del Laberinto/patología , Vestíbulo del Laberinto/cirugía
12.
Soft Matter ; 11(46): 9026-37, 2015 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-26403168

RESUMEN

We report on the fluidization dynamics of an attractive gel composed of non-Brownian particles made of fused silica colloids. Extensive rheology coupled to ultrasonic velocimetry allows us to characterize the global stress response together with the local dynamics of the gel during shear startup experiments. In practice, after being rejuvenated by a preshear, the gel is left to age for a time tw before being subjected to a constant shear rate [small gamma, Greek, dot above]. We investigate in detail the effects of both tw and [small gamma, Greek, dot above] on the fluidization dynamics and build a detailed state diagram of the gel response to shear startup flows. The gel may display either transient shear banding towards complete fluidization or steady-state shear banding. In the former case, we unravel that the progressive fluidization occurs by successive steps that appear as peaks on the global stress relaxation signal. Flow imaging reveals that the shear band grows until complete fluidization of the material by sudden avalanche-like events which are distributed heterogeneously along the vorticity direction and correlated to large peaks in the slip velocity at the moving wall. These features are robust over a wide range of tw and [small gamma, Greek, dot above] values, although the very details of the fluidization scenario vary with [small gamma, Greek, dot above]. Finally, the critical shear rate [small gamma, Greek, dot above]* that separates steady-state shear-banding from steady-state homogeneous flow depends on the width of the shear cell and exhibits a nonlinear dependence with tw. Our work brings about valuable experimental data on transient flows of attractive dispersions, highlighting the subtle interplay between shear, wall slip and aging whose modeling constitutes a major challenge that has not been met yet.

13.
Nat Genet ; 38(11): 1304-9, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17041600

RESUMEN

R-spondins are a recently characterized small family of growth factors. Here we show that human R-spondin1 (RSPO1) is the gene disrupted in a recessive syndrome characterized by XX sex reversal, palmoplantar hyperkeratosis and predisposition to squamous cell carcinoma of the skin. Our data show, for the first time, that disruption of a single gene can lead to complete female-to-male sex reversal in the absence of the testis-determining gene, SRY.


Asunto(s)
Diferenciación Celular/genética , Predisposición Genética a la Enfermedad , Procesos de Determinación del Sexo , Neoplasias Cutáneas/genética , Piel/citología , Trombospondinas/genética , Trombospondinas/fisiología , Animales , Carcinoma de Células Escamosas/genética , Células Cultivadas , Aberraciones Cromosómicas , Análisis Mutacional de ADN , Trastornos del Desarrollo Sexual , Femenino , Humanos , Queratodermia Palmoplantar/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Mutación , Linaje , Piel/embriología
14.
Acta Neurochir (Wien) ; 155(3): 449-54, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23307333

RESUMEN

BACKGROUND: Intracranial lipomas are extremely rare tumors, with certain clinical and radiological characteristics. METHODS: We considered the diagnostic evaluation and treatment options of seven patients presenting with lipoma in the cerebellopontine angle or internal acoustic meatus in our department. RESULTS: Mean age was 51, with four out of seven cases being women. Balance disorders (vertigo, dizziness) were the predominant symptoms (in six out of seven patients), followed by hearing loss. The diagnosis of intracranial lipomas was based on the results of imaging studies, especially on magnetic resonance imaging. The management of lipomas of the CPA and of the IAM should initially be conservative, including close follow-up of the patient and evaluation of a potential change in tumor size. Surgical management of CPA lipomas should be reserved for patients with intractable clinical symptoms due to tumor overgrowth. CONCLUSIONS: Diagnosis of CPA and IAM lipomas is considered to be a clinical and imaging challenge. As the complete resection of such lipomas is a risky choice and taking into account the benign course of such tumors, the only absolute surgical indication should be uncontrolled tumor growth.


Asunto(s)
Coristoma/cirugía , Lipoma/cirugía , Meninges , Neuroma Acústico/cirugía , Hueso Petroso/cirugía , Neoplasias Craneales/cirugía , Adulto , Coristoma/diagnóstico , Coristoma/patología , Diagnóstico Diferencial , Femenino , Humanos , Aumento de la Imagen , Interpretación de Imagen Asistida por Computador , Lipoma/diagnóstico , Lipoma/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroma Acústico/diagnóstico , Neuroma Acústico/patología , Hueso Petroso/patología , Neoplasias Craneales/diagnóstico , Neoplasias Craneales/patología
15.
Eur Arch Otorhinolaryngol ; 270(4): 1551-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23212692

RESUMEN

OBJECTIVES: To describe the clinical features, radiological findings, treatment and outcomes of three cases of endolymphatic sac tumors (ELST). METHODS: Retrospective analysis of three cases of ELST. RESULTS: The first patient had a large ELST invading the labyrinth after a long history of vertigo. He was recurrence-free 1 year after retrolabyrinthine surgical removal. In the second case, an acute peripheral facial nerve paralysis associated with ipsilateral sensorineural hearing loss led to the diagnosis. A translabyrinthine approach was used to remove the tumor, which recurred three times over 10 years. The third patient was a young woman suffering from von Hippel-Lindau (VHL) disease and referred for a sudden sensorineural hearing loss due to an intralabyrinthine hemorrhage secondary to a 2 mm-large endolymphatic sac-confined ELST. Her hearing was totally lost after the deafness recurred 1 month after this first episode. MRI demonstrated a small bilateral ELST. The patient refused surgery on the deaf side. CONCLUSION: ELST are difficult to diagnose due to the wide variety of their presentations. Patients with ELST should be screened for VHL disease. Dural invasion and tumor hypervascularization increase the risk of local recurrences after surgery. Early surgical resection may lead to complete tumor removal and inner ear preservation.


Asunto(s)
Neoplasias del Oído/diagnóstico , Neoplasias del Oído/cirugía , Saco Endolinfático/cirugía , Enfermedades del Laberinto/diagnóstico , Enfermedades del Laberinto/cirugía , Adulto , Audiometría de Tonos Puros , Neoplasias del Oído/patología , Saco Endolinfático/patología , Endoscopía , Parálisis Facial/etiología , Femenino , Perdida Auditiva Conductiva-Sensorineural Mixta/etiología , Pérdida Auditiva Súbita/etiología , Humanos , Enfermedades del Laberinto/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Primarias Múltiples/patología , Neoplasias Primarias Múltiples/cirugía , Reoperación , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Vértigo/etiología , Adulto Joven , Enfermedad de von Hippel-Lindau/diagnóstico , Enfermedad de von Hippel-Lindau/patología , Enfermedad de von Hippel-Lindau/cirugía
16.
Surg Radiol Anat ; 35(1): 55-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22722753

RESUMEN

PURPOSE: To assess the presence of dehiscence of the superior semicircular canal (SSCC) on computed tomography (CT) scanning and to study the microscopic anatomo-radiological correlation. MATERIALS AND METHODS: Thirty-seven temporal bones preserved in formalin, regardless of the clinical history of cadavers, were studied. A microscopic anatomical study was conducted with an operative microscope (20×). The settings of the CT permitted to obtain 0.6 mm slices contiguous reconstruction in Pöschl plane and in Stenvers plane. Three-dimensional (3D) reconstructions were performed if a radiological dehiscence was observed. The apex thickness was measured in Pöschl plane. The radiological positive criterion of SSCC dehiscence was an absence of bone coverage of more than 1 mm long in Pöschl and Stenvers planes. RESULTS: We observed three dehiscences of the 37 temporal bones on CT in Pöschl and Stenvers planes. However, no dehiscence was found microscopically. The 3D reconstruction was also positive in these three cases. Reconstructions in the Pöschl plane offered good results up to a bone thickness of 0.6 mm. When it was lower than 0.6 mm, the interpretation of the images appeared to be subjective. CONCLUSION: This study emphasizes the limitations of CT imaging, with a risk of false positives to take into account when interpreting the images. The 3D reconstructions also give too many false positives to be used alone and make an accurate diagnosis. The diagnosis of SSCC dehiscence will therefore remain clinical. Complementary and instrumental radiological examinations should be performed only to confirm this clinical suspicion.


Asunto(s)
Desmineralización Ósea Patológica/diagnóstico por imagen , Canales Semicirculares/diagnóstico por imagen , Hueso Temporal/anatomía & histología , Hueso Temporal/diagnóstico por imagen , Cadáver , Femenino , Humanos , Masculino , Microscopía Electrónica , Canales Semicirculares/anatomía & histología , Tomografía Computarizada por Rayos X/métodos
17.
Phys Rev E ; 108(2-1): 024901, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37723689

RESUMEN

We report an instability of a slider slowly dragged at the surface of a granular bed in a quasistatic regime. The boat-shaped slider sits on the granular medium under its own weight and is free to translate vertically and to rotate around the pitch axis while a constant horizontal speed is imposed. For a wide range of parameters (mass, length, shape, velocity) a regular pattern of peaks and troughs spontaneously emerges as the slider travels forward. This instability is studied through experiments using a conveyor belt and by means of two-dimensional discrete elements method simulations. We show that the wavelength and amplitude of the pattern scale as the length of the slider. We also observe that the ripples disappear for low and high masses, indicating an optimal confining pressure. The effect of the shape, more specifically the inclination of the front spatula, is studied and found to drastically influence both the wavelength and the amplitude. Finally, we show that the mechanical details (friction, cohesion) of the contact point between the slider and the pulling device is critical and remains to be fully understood.

18.
J Clin Med ; 12(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36836083

RESUMEN

(1) Background: Pelvic organ prolapse (POP) can be managed using a vaginal pessary. However, the decision-making process whereby health professionals choose the right pessary is unclear. The objective of this study was to focus on the experience of experts in pessary use and to propose an algorithm. (2) Methods: A prospective study, based on face-to-face semi-directive interviews and group discussions, was conducted on a multidisciplinary panel of professional experts specialized in pessary prescriptions. A consensual algorithm was established, and its accuracy was assessed by expert and non-expert panels. The Consolidated Criteria for Reporting Qualitative Studies (COREQ) were used. (3) Results: 17 semi-directive interviews were conducted. The parameters involved in the decision-making process regarding the choice of vaginal pessaries were: desire for self-management (65%), associated urinary stress incontinence (47%), POP type (41%), and POP stage (29%). The algorithm was developed step by step (4 iterations) using the Delphi technique. Most of the expert panel (76%) rated the relevance of the algorithm as 7 or more out of 10 on a visual analog scale according to their own experience (reference activity). Finally, most (81%) of the non-expert panel (n = 230) rated the usefulness of this algorithm as 7 or more out of 10 on a visual analog scale. (4) Conclusions: This study provides an expert panel-based algorithm that may help in the prescription of pessaries for POP.

19.
Am J Otolaryngol ; 33(1): 168-73, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21696856

RESUMEN

OBJECTIVE: Malignant transformation of vestibular schwannoma is considered a rare clinical entity. Radiotherapy, as a treatment option for vestibular schwannoma, is regarded as a potential risk factor for secondary malignancy. Recently, radiotherapy with dose fractionation has been proposed, intended to diminish the risk of radiation-induced neuropathy. CASE PRESENTATION: The aim of the present study is to report the first case, to the best of our knowledge, of malignant transformation of a residual vestibular schwannoma 19 years after fractionated radiotherapy, describing its characteristics with regard to those previously reported in the literature. CONCLUSIONS: The main purpose of the present work is to state that the knowledge of the iatrogenic potential pitfalls of any technique of radiotherapy in clinical oncology is becoming a necessity. Finally, our report demonstrates that the irradiated patients must be monitored for life because a secondary malignancy may appear after a very long delay.


Asunto(s)
Transformación Celular Neoplásica/patología , Neuroma Acústico/patología , Neuroma Acústico/radioterapia , Adulto , Terapia Combinada , Femenino , Humanos , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia , Neuroma Acústico/cirugía , Factores de Riesgo , Tomografía Computarizada por Rayos X
20.
Phys Rev E ; 106(2-1): 024901, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36109955

RESUMEN

Different regimes are usually observed for fluid migration through an immersed granular layer. In this work, we report a puzzling behavior when injecting water at a constant flow rate through a nozzle at the bottom of an immersed granular layer in a Hele-Shaw cell. In a given range of parameters (granular layer height and fluid flow rate) the granular bed is not only fluidized, but the particle-laden jet also exhibits periodic oscillations. The frequency and amplitude of the oscillations are quantified. The Strouhal number displays a power-law behavior as a function of a nondimensional parameter, J, defined as the ratio between the jet velocity at the initial granular bed height and the inertial particle velocity. Fluid-particle coupling is responsible for the jet oscillations. This mechanism could be at the origin of the cyclic behavior of pockmarks and mud volcanoes in sedimentary basins.

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