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1.
Sensors (Basel) ; 24(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38544040

RESUMO

The Self-Mixing Interformeter (SMI) is a self-aligned optical interferometer which has been used for acoustic wave sensing in air through the acousto-optic effect. This paper presents how to use a SMI for the measurement of Sound Pressure Level (SPL) in acoustic waveguides. To achieve this, the SMI is first calibrated in situ as a vibrometer. The optical feedback parameters C and α in the strong feedback regime (C≥4.6) are estimated from the SMI vibrometric signals and by the solving of non-linear equations governing the SMI behaviour. The calibration method is validated on synthetic SMI signals simulated from SMI governing equations for C ranging from 5 to 20 and α ranging from 4 to 10. Knowing C and α, the SMI is then used as an acoustic pressure sensor. The SPLs obtained using the SMI are compared with a reference microphone, and a maximal deviation of 2.2 dB is obtained for plane waves of amplitudes ranging from 20 to 860 Pa and frequencies from 614 to 17,900 Hz. The SPL measurements are carried out for C values ranging from 7.1 to 21.5.

2.
JASA Express Lett ; 3(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37819231

RESUMO

This work presents a sensitivity study on the use of an optical feedback interferometer to measure acoustic pressure from plane waves. The sensitivity is established by linearising the interferometer's governing equations. It is shown to be independent of the acoustic wave frequency but dependent on configuration parameters such as the optical feedback parameter or the length of the laser through which the acoustic wave passes. Experimental validation is carried out using three acoustic waveguides in the 0.5-18 kHz range. The sensitivity obtained enables broadband acoustic pressure measure with a low mean relative error in comparison with a reference condenser microphone.

3.
J Diabetes ; 12(1): 48-57, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31166087

RESUMO

BACKGROUND: Liver adenomatosis (LA) is a rare disease resulting from biallelic inactivation of the hepatocyte nuclear factor-1 alpha (HNF1A) gene, which induces the proliferation of adenoma cells in liver parenchyma. Liver adenomatosis has only been documented in case reports from patients carrying a HNF1A germline mutation. We have evaluated the frequency of LA among a large cohort of patients with HNF1A-maturity onset diabetes of the young (MODY), previously termed "MODY3," and herein describe its clinical, radiological, and pathological characteristics. METHODS: In all, 137 HNF1A-MODY subjects from 74 families were screened by liver ultrasonography in 13 centers, and 15 additional cases of LA were later included in the series. Liver adenomatosis was confirmed by liver computed tomography, magnetic resonance imaging (MRI), and/or histopathology. RESULTS: Among 137 carriers of an HNF1A mutation, 9 patients (6.5%) from seven families were diagnosed with LA. Diabetes mellitus was present in 87.5% of patients with LA. In 25% of patients, LA was diagnosed due to intra-abdominal or intratumoral bleeding. Liver biochemistry was near normal in all patients. Liver imaging showed adenomas of various sizes and numbers. On MRI, most nodules had the radiological characteristics of steatotic adenomas. Histopathological confirmation of LA was available in 13 cases, and these adenomas were mostly steatotic. Surgery was initially performed in 37.5% of patients, and liver disease progression was observed in 30%. No disease progression was observed in 14 pregnancies. CONCLUSIONS: The frequency of LA in a cohort of screened HNF1A-MODY patients and the high incidence of LA progression and/or hemorrhage warrants systematic screening for liver adenomatosis in HNF1A-MODY families.


Assuntos
Adenoma/genética , Diabetes Mellitus Tipo 2/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Neoplasias Hepáticas/genética , Mutação , Adenoma/diagnóstico por imagem , Adenoma/patologia , Adolescente , Adulto , Criança , Estudos de Coortes , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/patologia , Diagnóstico por Imagem/métodos , Saúde da Família , Feminino , França , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
J Acoust Soc Am ; 143(2): 811, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29495749

RESUMO

This paper investigates the compensation of room reflections based on Ambisonics. A multichannel room equalization method for Ambisonic playback systems is proposed. The compensation filters are designed to operate in the spherical harmonics domain, prior to the decoding step. Their design requires the inversion of a matrix which can be ill-conditioned at low frequencies and for higher Ambisonic orders. A crossover and cross-order method is proposed to circumvent this problem and to reduce the amount of necessary regularization. Simulation results are presented in frequency, space, and temporal domains over a wide-range of frequencies. It is shown that the proposed method is efficient and can reduce the reproduction error to -14 dB in the reconstruction area defined in free field. Practical considerations such as Ambisonic room response estimation and robustness of the method are investigated. Experimental results are provided and show good agreement with the theory. Finally, a glimpse into the extension of the proposed method to create three-dimensional measurement-based Ambisonic reverberation is discussed.

5.
Eur J Endocrinol ; 172(3): 309-19, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25538206

RESUMO

OBJECTIVE: Management of insulinomas in the context of MEN1 remains poorly studied. The aim of this study was to evaluate long-term results of various surgical approaches in a large cohort of insulinoma-MEN1 patients. DESIGN AND METHODS: Consecutive insulinoma-MEN1 patients operated on for a nonmetastatic insulinoma between 1957 and 2010 were retrospectively selected from the MEN1 database of the French Endocrine Tumor Group. The type of surgery was categorized as distal pancreatectomy (DP), total pancreatectomy/cephalic duodenopancreatectomy (TP/CDP), or enucleation (E). Primary endpoint was time until recurrence of hypoglycemia after initial surgery. Secondary endpoints were post-operative complications. RESULTS: The study included 73 patients (median age=28 years). Surgical procedures were DP (n=46), TP/CDP (n=9), or E (n=18). After a median post-operative follow-up of 9.0 years (inter-quartile range (IQR): 2.5-16.5 years), 60/73 patients (82.2%) remained hypoglycemia free. E and TP/CDP were associated with a higher risk of recurrent hypoglycemia episodes (unadjusted hazard ratio: 6.18 ((95% CI: 1.54-24.8); P=0.010) for E vs DP and 9.51 ((95% CI: 1.85-48.8); P=0.007) for TP/CDP vs DP. After adjustment for International Union against Cancer pTNM classification, enucleation remained significantly associated with a higher probability of recurrence. Long-term complications had occurred in 20 (43.5%) patients with DP, five (55.6%) with TP/CDP, but in none of the patients who have undergone E (P=0.002). CONCLUSION: In the French Endocrine database, DP is associated with a lower risk for recurrent hypoglycemia episodes. Due to lower morbidity, E alone might be considered as an alternative.


Assuntos
Insulinoma/cirurgia , Neoplasia Endócrina Múltipla Tipo 1/cirurgia , Adolescente , Adulto , Feminino , Humanos , Insulinoma/patologia , Masculino , Neoplasia Endócrina Múltipla Tipo 1/patologia , Pancreatectomia , Pancreaticoduodenectomia , Estudos Retrospectivos , Adulto Jovem
6.
Biol Reprod ; 91(2): 50, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24943040

RESUMO

INTELECTIN (ITLN) is an adipokine involved in the regulation of insulin sensitivity and inflammatory and immunity responses. Serum ITLN levels are lower in obese, diabetic, and polycystic ovary syndrome (PCOS) women than in control subjects. ITLN has never been studied in ovarian cells. Here, we identified ITLN1 in human ovarian follicles and investigated the molecular mechanisms involved in the regulation of its expression in response to the insulin sensitizers metformin and rosiglitazone, in human granulosa-lutein cells (hGLCs) and in a human ovarian granulosa-like tumor cell line (KGN). We also studied the effects of human recombinant ITLN1 (hRom1) on steroid production and on the activation of various signaling pathways. Using RT-PCR, immunoblotting, and immunohistochemistry, we found that INTL1 is present in human follicular cells. Using ELISA, we showed that INTL levels are similar in plasma and follicular fluid (FF) in control patients, whereas they are higher in FF than in plasma in PCOS patients. In KGN cells and hGLCs, insulin (10(-8) M), insulin-like growth factor-1 (IGF-1; 10(-8) M), and metformin (10(-2) M or 10(-3) M) increased INTL1 expression (mRNA and protein) after 12 and 24 h of stimulation. For metformin, this effect was mediated by adenosine monophosphate-activated kinase (PRKA). Furthermore, hRom1 increased nicotinamide phosphoribosyltransferase (NAMPT) expression in KGN and hGLCs. We also showed that hRom1 increased IGF-1-induced progesterone and estradiol secretion and this was associated with an increase in the STAR and CYP19A1 protein levels and an increase in IGF-1R signaling. Furthermore, all these data were abolished when NAMPT was knocked down in KGN cells, suggesting that INTL1 improves IGF-1-induced steroidogenesis through induction of NAMPT in hGLCs.


Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Lectinas/metabolismo , Células Lúteas/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Esteroides/biossíntese , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Adulto , Aromatase/genética , Aromatase/metabolismo , Citocinas/genética , Estradiol/biossíntese , Feminino , Hormônio Foliculoestimulante/farmacologia , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Hipoglicemiantes/farmacologia , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Lectinas/genética , Hormônio Luteinizante/farmacologia , Metformina/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Nicotinamida Fosforribosiltransferase/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo
7.
Presse Med ; 42(5): 830-8, 2013 May.
Artigo em Francês | MEDLINE | ID: mdl-23566620

RESUMO

Between 2001 and 2007, treatments for type 2 diabetes have increased and therapeutic choices have improved. However glycemic control remains insufficient. Cardiovascular risk control has widely increased. Statins, hypertensive and antithrombotic treatments are more often prescribed. Blood pressure and LDL cholesterol levels have decreased whatever age. However, progress remains possible, especially regarding blood pressure control. Obesity has increased between 2001 and 2007 to reach 41% whereas the frequency of dietetic visits has decreased. Insulin therapy (more than obesity) determines the frequency of dietetic visits: dietetic care happens too late. Important improvements of the quality of follow-up are observed. However, fundus exams and more specifically albuminuria measurement remain insufficiently performed and their progression is too slow, as well as the podiatric examination. Only 10% of people with type 2 diabetes have an endocrinology visit, which has been stable between 2001 and 2007. Information expectations of people with type 2 diabetes are strong, especially for diet. Education demand is lower but more important for people who have already benefited. This improvement of medical care leads to an increase in the cost of reimbursements. The consequences of diabetes, more than the disease itself, alter the quality of life.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Anticolesterolemiantes/economia , Anticolesterolemiantes/uso terapêutico , Anti-Hipertensivos/economia , Anti-Hipertensivos/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/economia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Comorbidade , Efeitos Psicossociais da Doença , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/economia , Pé Diabético/prevenção & controle , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/prevenção & controle , Dietética , Gerenciamento Clínico , Uso de Medicamentos , Endocrinologia , França/epidemiologia , Custos de Cuidados de Saúde , Humanos , Hipoglicemiantes/economia , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Obesidade/dietoterapia , Obesidade/epidemiologia , Educação de Pacientes como Assunto , Qualidade de Vida , Encaminhamento e Consulta/estatística & dados numéricos , Risco
8.
Hum Mol Genet ; 22(10): 1940-8, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23376981

RESUMO

Multiple endocrine neoplasia syndrome type 1 (MEN1), which is secondary to mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Although genotype-phenotype studies have so far failed to identify any statistical correlations, some families harbor recurrent tumor patterns. The function of MENIN is unclear, but has been described through the discovery of its interacting partners. Mutations in the interacting domains of MENIN functional partners have been shown to directly alter its regulation abilities. We report on a cohort of MEN1 patients from the Groupe d'étude des Tumeurs Endocrines. Patients with a molecular diagnosis and a clinical follow-up, totaling 262 families and 806 patients, were included. Associations between mutation type, location or interacting factors of the MENIN protein and death as well as the occurrence of MEN1-related tumors were tested using a frailty Cox model to adjust for potential heterogeneity across families. Accounting for the heterogeneity across families, the overall risk of death was significantly higher when mutations affected the JunD interacting domain (adjusted HR = 1.88: 95%-CI = 1.15-3.07). Patients had a higher risk of death from cancers of the MEN1 spectrum (HR = 2.34; 95%-CI = 1.23-4.43). This genotype-phenotype correlation study confirmed the lack of direct genotype-phenotype correlations. However, patients with mutations affecting the JunD interacting domain had a higher risk of death secondary to a MEN1 tumor and should thus be considered for surgical indications, genetic counseling and follow-up.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1/genética , Neoplasia Endócrina Múltipla Tipo 1/mortalidade , Mutação , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas/genética , Família , Feminino , Seguimentos , Humanos , Masculino , Neoplasia Endócrina Múltipla Tipo 1/metabolismo , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fatores de Risco
9.
Ann Endocrinol (Paris) ; 73(6): 515-22, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23131470

RESUMO

OBJECTIVES: Several cases of testicular adrenal rest tumours have been reported in men with congenital adrenal hyperplasia (CAH) due to the classical form of 21-hydroxylase deficiency but the prevalence has not been established. The aims of this report were to evaluate the frequency of testicular adrenal rest tissue in this population in a retrospective multicentre study involving eight endocrinology centres, and to determine whether treatment or genetic background had an impact on the occurrence of adrenal rest tissue. MATERIAL AND METHODS: Testicular adrenal rest tissue (TART) was sought clinically and with ultrasound examination in forty-five males with CAH due to the classical form of 21-hydroxylase deficiency. When the diagnosis of testicular adrenal rest tumours was sought, good observance of treatment was judged on biological concentrations of 17-hydroxyprogesterone (17OHP), delta4-androstenedione, active renin and testosterone. The results of affected and non-affected subjects were compared. RESULTS: TART was detected in none of the 18 subjects aged 1 to 15years but was detected in 14 of the 27 subjects aged more than 15years. Five patients with an abnormal echography result had no clinical signs. Therapeutic control evaluated at diagnosis of TART seemed less effective when diagnosis was made in patients with adrenal rest tissue compared to TART-free subjects. Various genotypes were observed in patients with or without TART. CONCLUSION: Due to the high prevalence of TART in classical CAH and the delayed clinical diagnosis, testicular ultrasonography must be performed before puberty and thereafter regularly during adulthood even if the clinical examination is normal.


Assuntos
Hiperplasia Suprarrenal Congênita/epidemiologia , Tumor de Resto Suprarrenal/epidemiologia , Neoplasias Testiculares/epidemiologia , Adolescente , Hiperplasia Suprarrenal Congênita/complicações , Hiperplasia Suprarrenal Congênita/diagnóstico por imagem , Tumor de Resto Suprarrenal/complicações , Tumor de Resto Suprarrenal/diagnóstico por imagem , Adulto , Criança , Pré-Escolar , França/epidemiologia , Humanos , Masculino , Prevalência , Estudos Retrospectivos , Análise do Sêmen , Neoplasias Testiculares/complicações , Neoplasias Testiculares/diagnóstico por imagem , Ultrassonografia , Adulto Jovem
10.
J Clin Endocrinol Metab ; 97(6): E1068-73, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22466334

RESUMO

CONTEXT: Pituitary stalk interruption represents a frequent feature of congenital hypopituitarism, but only rare cases have been assigned to a known genetic cause. OBJECTIVE: Using a candidate gene approach, we tested several genes as potential causes of hypopituitarism with pituitary stalk interruption. We hypothesized that ectopic posterior pituitary may be a consequence of defective neuronal axon projections along the pituitary stalk or defective angiogenesis of hypophyseal portal circulation. Considering the role of the prokineticin 2 pathway in angiogenesis and neuronal migration, we screened PROK2 and PROKR2 genes. DESIGN: PROK2 and PROKR2 and all genes previously known to be involved in hypopituitarism with pituitary stalk interruption (LHX4, HESX1, OTX2, and SOX3) were screened in 72 index cases with pituitary stalk interruption syndrome from the GENHYPOPIT database. In vitro studies were performed to assess the functional consequences of allelic variants. RESULTS: We identified two heterozygous PROKR2 mutations (p.Leu173Arg and p.Arg85His) previously reported in isolated hypogonadotroph hypogonadism and a novel PROKR2 variant (p.Ala51Thr) that, in contrast with both other mutations, did not impair receptor signaling activity. Three allelic variants of HESX1 were identified: the heterozygous p.Phe156Ser and the homozygous p.Arg109X mutations were functionally deleterious, whereas p.Ser67Thr was found as a rare allelic variant in association with p.Arg85His PROKR2 mutation in the same patient. CONCLUSIONS: We report PROKR2 variants in congenital hypopituitarism with pituitary stalk interruption, suggesting a potential role of the prokineticin pathway in pituitary development.


Assuntos
Hipopituitarismo/genética , Hipófise/anormalidades , Mutação Puntual , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Adolescente , Adulto , Criança , Saúde da Família , Feminino , Hormônios Gastrointestinais/genética , Células HEK293 , Heterozigoto , Humanos , Hipopituitarismo/congênito , Hipopituitarismo/patologia , Masculino , Neuropeptídeos/genética , Linhagem
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