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1.
Nature ; 450(7170): 654-6, 2007 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-18046399

RESUMO

Venus has no significant internal magnetic field, which allows the solar wind to interact directly with its atmosphere. A field is induced in this interaction, which partially shields the atmosphere, but we have no knowledge of how effective that shield is at solar minimum. (Our current knowledge of the solar wind interaction with Venus is derived from measurements at solar maximum.) The bow shock is close to the planet, meaning that it is possible that some solar wind could be absorbed by the atmosphere and contribute to the evolution of the atmosphere. Here we report magnetic field measurements from the Venus Express spacecraft in the plasma environment surrounding Venus. The bow shock under low solar activity conditions seems to be in the position that would be expected from a complete deflection by a magnetized ionosphere. Therefore little solar wind enters the Venus ionosphere even at solar minimum.

2.
Eur Ann Otorhinolaryngol Head Neck Dis ; 139(2): 73-76, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34140266

RESUMO

OBJECTIVES: To study voice prosthesis survival, complications, efficacy and impact on quality of life. METHODS: A single-center observational study was performed in patients treated for squamous cell carcinoma of the larynx or hypopharynx by total (pharyngo)-laryngectomy between 2010 and 2015. Study data comprised: maximum phonation time (sec), number of and reasons for prosthesis exchanges (leakage through or around the prosthesis, expulsion or inclusion of the prosthesis), plus 2 quality of life questionnaires (QLQ-C30, QLQ-H&N35) and the Voice Handicap Inventory (VHI 30). RESULTS: Forty-nine patients were included. The most common causes of prosthesis exchange were leakage through (73.2%) or around the prosthesis (18.5%). The median time between exchanges was 4 months. Global quality of life status on the QLQ-C30 was 63.5. Mean maximum phonation time was 7.4sec. Mean VHI was 46/120; 10 patients had a mild voice handicap, 12 moderate and 10 severe. No relation emerged between the number of prosthesis exchanges per year and quality of life. Voice handicap significantly decreased quality of life, with QLQ-C30 72.3 for the 22 patients with mild to moderate voice handicap and 44.2 for the 10 patients with severe voice handicap (P=0.001). CONCLUSION: Voice restoration by tracheoesophageal prosthesis after total (pharyngo)-laryngectomy is a reliable technique that decreases voice handicap and, despite potentially serious complications, has little negative impact on quality of life.


Assuntos
Neoplasias Laríngeas , Laringe Artificial , Carcinoma de Células Escamosas de Cabeça e Pescoço , Voz , Humanos , Neoplasias Laríngeas/cirurgia , Laringectomia/efeitos adversos , Laringectomia/métodos , Qualidade de Vida , Fala , Carcinoma de Células Escamosas de Cabeça e Pescoço/cirurgia
3.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S11-S18, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32863156

RESUMO

OBJECTIVE: Multi-centre study of the National French Registry (EPIIC) of patients with cochlear implants, focusing on infants who were operated-on under the age of 24 months between 2012 and 2016. PATIENTS AND METHODS: A total of 615 profoundly deaf infants, who received cochlear implants (CIs) before their second birthday, were included in the registry by different CI centers. Epidemiological, surgical, speech therapy and school, follow-up data were included in the registry, 12, 24, 36 and 48 months thereafter. The following parameters were studied: type of implantation (uni- or bilateral), complications, cause of deafness, category of auditory perception (CAP), Open-set word recognition score (OSW), speech intelligibility rating, lexical comprehension with EVIP (Peabody), communication mode and type of schooling. Bilateral simultaneous CI (BiCI) and unilateral CI (UniCI) groups were compared. RESULTS: There were 744 implantations. The explantation-reimplantation rate, within the four-year follow-up, was just 3.6%. Mean implantation age was 16.0 months, and similar in the two groups (BiCI/UniCI). A total of 51% of children had their first implant between 12 and 18 months, and 15% before 12 months. Implantation was unilateral in 52% of cases. Fifty-six percent of the bilateral procedures were sequential, with a mean delay of 16.8 months for the second implantation. The cause of deafness was unknown in 52% of cases. Of the 48% (297/615) of attributed cases, 32% had clear genetic causes. The remaining deafness was due to cytomegalovirus (CMV, 8%), inner-ear malformation (5%) and meningitis (3%). The main complications were from infections (47%) and internal device failure (25%). Four years post-operation, 84% of the UniCI and 75% of BiCl groups had a CAP≥5, and 83% of UniCl and 100% BiCI had OSW≥80%. Furthermore 74% of UniCI and 77% of BiCI communicated orally and 85% of UniCI and 90% of BiCI integrated into mainstream schooling. CONCLUSION: The French Registry of cochlear implants (EPIIC) is the only such national registry in the world. Our analysis illustrates the immediate benefits of, either single or double, cochlear implantation for language, perception skills and schooling.


Assuntos
Percepção Auditiva , Linguagem Infantil , Implante Coclear/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Surdez/reabilitação , Sistema de Registros/estatística & dados numéricos , Fatores Etários , Implante Coclear/efeitos adversos , Implante Coclear/métodos , Implantes Cocleares/efeitos adversos , Comunicação , Correção de Deficiência Auditiva/instrumentação , Correção de Deficiência Auditiva/estatística & dados numéricos , Surdez/etiologia , Remoção de Dispositivo/estatística & dados numéricos , Educação de Pessoas com Deficiência Auditiva/métodos , Educação de Pessoas com Deficiência Auditiva/estatística & dados numéricos , Seguimentos , França , Humanos , Lactente , Recém-Nascido , Inclusão Escolar/estatística & dados numéricos , Reoperação/estatística & dados numéricos , Instituições Acadêmicas , Inteligibilidade da Fala , Fonoterapia/estatística & dados numéricos , Fatores de Tempo
4.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S45-S49, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32826202

RESUMO

This study aims to determine the frequency and causes of cochlear explants with re-implantation (ERI) after 5 years' follow up of the patients included in the French national EPIIC (étude post-inscription des implants cochléaires) registry tracking patients with cochlear implantation. This multicenter, descriptive prospective study was conducted on 5051 patients enrolled in the EPIIC database between January 2012 and December 2016. Ninety-five patients (1.9%) received a primary implant and an ERI during the study. Of these, four benefitted from two ERIs. The number of ERIs was significantly higher in the pediatric population than among adults. The explantation and reimplantation were performed simultaneously in 86% of cases. The reasons for explantation were: in 46.4% of cases linked to a malfunction of the implant, and in 39.3% of cases for medical or surgical reasons. The number of electrodes inserted was significantly higher after the ERI than after the first implantation. There was just one post-ERI infection for these 95 explanted and re-implanted patients. As well as explantation with reimplantation rarely being necessary, it generally presents no major surgical difficulty and in most cases it allows a better integration than in the first implantation.


Assuntos
Implante Coclear/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Remoção de Dispositivo/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Reoperação/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Implantes Cocleares/efeitos adversos , França , Humanos , Lactente , Pessoa de Meia-Idade , Estudos Prospectivos , Falha de Prótese , Reimplante/estatística & dados numéricos , Fatores de Tempo , Adulto Jovem
5.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S57-S63, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32792302

RESUMO

This study concerns the results of cochlear implantation in children and adults from French cochlear implantation centers, monitored at one, two and three years by the Cochlear Implant French Registry EPIIC. This multicenter study enrolled 2603 subjects (1667 adults and 936 children) implanted in one ear. The following parameters were studied: hearing overall performances, monosyllabic or dissyllabic word perception, speech intelligibility, self-assessment questionnaire of Cochlear Implant (CI) benefits (Abbreviated profile of Hearing aid Benefit); professional activity and schooling. This study confirms the ceiling effect in adults' performances after the 1st year and the progressive growth in children's performances. It also shows that the contralateral hearing aid enhances performances compared to the CI alone condition, in all follow-up sessions. The French register of CIs is the only worldwide register of systematic follow-up on a period of three years and more of all adults and children implanted in a country.


Assuntos
Implante Coclear/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Surdez/reabilitação , Qualidade de Vida , Sistema de Registros/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Percepção Auditiva , Criança , Pré-Escolar , Educação , Emprego , Seguimentos , França , Humanos , Lactente , Recém-Nascido , Autoavaliação (Psicologia) , Inteligibilidade da Fala , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
6.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S19-S25, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32773333

RESUMO

OBJECTIVES: To analyze the performance of cochlear implants in French patients aged 65 and over, implanted between 2012 and 2016, using data from the French national registry for cochlear implants (EPIIC). MATERIALS AND METHODS: The French national registry incorporates patient data from before implantation and for three years after implantation, stratified in different age groups (18-39, 40-64years, 65-74years and>75years). Here, we assessed the latter two categories. Hearing was assessed using mono- and disyllabic words in a silent background. The Category of Auditory Performance (CAP) scale was also implemented and subjects took the Abbreviated Profile of Hearing Aid Benefit (Aphab) questionnaire. RESULTS: The population aged over 65 accounted for 38% (n=1193) of the 3178 adult implanted patients. The performance for mono- and disyllabic words in silence, the CAP scores and the APHAB questionnaire answers for ease of communication, background noise and reverberation were dramatically improved at one year post-implantation (P<0.0001 for each score) and remained stable between one and three years thereafter. The percentage improvement was similar across all age groups. The scores for loud-noise intolerance did not change after cochlear implantation in any age group. CONCLUSION: Cochlear implants improve hearing and communication in subjects aged 65 and over, with comparable efficiency to that achieved in younger subjects. Cochlear implantation should thus be proposed whenever hearing aids provide only limited benefit. However, between 2012 and 2016, cochlear implantation was given to less than 1% of the French population aged 65 and over with profound deafness.


Assuntos
Implante Coclear/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Perda Auditiva/reabilitação , Sistema de Registros/estatística & dados numéricos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Percepção Auditiva , Implante Coclear/métodos , Comunicação , Feminino , França , Inquéritos Epidemiológicos , Perda Auditiva/etiologia , Testes Auditivos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Ruído/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
7.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S27-S35, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32763084

RESUMO

OBJECTIVE: Evaluate in France the outcomes of cochlear implantation outside the selection criteria, off-label. MATERIAL AND METHODS: This is a prospective cohort study including adults and children having received a cochlear implant (CI) in an off-label indication, that is outside the criteria established by the "Haute Autorité de santé (HAS)" in 2012. The data was collected from the "EPIIC" registry on recipients who received CIs in France between 2011 and 2014. Speech audiometry was performed at 60dB preimplantation and after one year of CI use, as well as an evaluation of the scores of the quality of life with the APHAB questionnaire, the scores for CAP and the professional/academic status in pre- and post-implantation conditions. Major and minor complications at surgery have been recorded. RESULTS: In total, 590 patients (447 adults and 143 children) with an off-label indication for CIs were included in this study from the EPIIC registry (11.7% of the whole cohort of EPIIC). For adults, the median percentage of comprehension using monosyllabic word lists was 41% in preimplantation condition versus 53% after one year of CI use (P<0.001) and 60% versus 71% in dissyllabic word lists (P<0.001). The CAP scores were 5 versus 6 in pre- and post-implantation conditions respectively (P<0.001) and the APHAB scores were statistically lower after implantation (P<0.001). In the children cohort, the median percentage of comprehension using monosyllabic word lists was 51% in preimplantation condition and 65% after CI (P<0.001), and 48% versus 82% (P<0.001) for dissyllabic word lists. The CAP scores were 5 versus 7 respectively in pre- and post-CI conditions (P<0.001). Thirty-two minor complications (5.4%) and 17 major complications (2.8%) were reported in our panel of off-label indication patients. CONCLUSION: These results suggest that a revision of the cochlear implantation candidacy criteria is necessary to allow more patients with severe or asymmetric hearing loss to benefit from a CI when there is an impact on quality of life despite the use of an optimal hearing aid.


Assuntos
Implante Auditivo de Tronco Encefálico/estatística & dados numéricos , Implante Coclear/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Perda Auditiva/reabilitação , Seleção de Pacientes , Sistema de Registros/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Audiometria da Fala/métodos , Criança , Pré-Escolar , Implante Coclear/efeitos adversos , Implantes Cocleares/efeitos adversos , Feminino , França/epidemiologia , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Uso Off-Label/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Cuidados Pré-Operatórios , Estudos Prospectivos , Qualidade de Vida , Adulto Jovem
8.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S51-S56, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32739279

RESUMO

OBJECTIVES: Assessment of the incidence and results of bilateral cochlear implantation in adults and children in France. MATERIALS AND METHODS: Multicenter retrospective study of data in the French national registry of cochlear implantations from January 1st 2012 to December 31st 2016. Functional results from CAP (Category of Auditory Performance) questionnaires and speech audiometry tests, with mono- and di-syllabic word-lists, were compared before and after implantation. Speech audiometry tests were carried out against a noisy background, except before simultaneous implantations. RESULTS: Nine hundred and forty two bilateral cochlear implantations were performed during this period, that is, 16.4% of all cochlear implantations. Five hundred and eighty eight bilateral implantations were performed sequentially. 59% of the bilateral implantations were performed in children. Bilateral implants significantly improved CAP scores in all cases (P<0.001). Auditory performance, with the two types of word-list, were significantly improved after simultaneous implantation (P<0.01). After sequential implantation, the speech discrimination score, already very good with the first implant, reached 63±26% [0-100] with monosyllabic word lists, and 72±28% [0-100] with dissyllabic words. There were more complications due to surgery in bilateral cases than in the entire population of cochlear recipients (9.1% vs 6.4%, P<0.02). CONCLUSION: Hearing is significantly improved by simultaneous cochlear implantation. For sequential implantation, at one year, when auditory results were already excellent from the first implant, in the bimodal condition CAP scores were significantly improved, although there was no further change in speech audiometry in noise.


Assuntos
Implante Coclear/métodos , Implantes Cocleares/estatística & dados numéricos , Surdez/reabilitação , Sistema de Registros/estatística & dados numéricos , Adulto , Audiometria da Fala/métodos , Percepção Auditiva , Criança , Implante Coclear/efeitos adversos , Implante Coclear/estatística & dados numéricos , Surdez/etiologia , Feminino , França , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Testes de Discriminação da Fala/estatística & dados numéricos
9.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S5-S9, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32891589

RESUMO

Cochlear and brainstem implants have been included on the list of reimbursable products (LPPR) in France since March of 2009. The implants were initially inscribed for 5 years, after which an application for renewal with the French National Commission for the Evaluation of Medical Devices and Health Technologies (Commission Nationale d'évaluation des dispositifs médicaux et des technologies de santé - CNEDiMTS) was required [Haute Autorité de santé, 2009]. Upon registration to the list of reimbursable products, the companies and the reference centers for cochlear and brainstem implants were asked to set up a post-registration registry called EPIIC. This article reports the evolution in the EPIIC registry of the general indicators for 5051 patients over the five years from 2012-2016.


Assuntos
Implantes Auditivos de Tronco Encefálico/estatística & dados numéricos , Implantes Cocleares/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Comitês Consultivos/organização & administração , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Implantes Auditivos de Tronco Encefálico/economia , Implante Coclear/estatística & dados numéricos , Implantes Cocleares/economia , Segurança Computacional , Bases de Dados como Assunto , Aprovação de Equipamentos/legislação & jurisprudência , Remoção de Dispositivo/estatística & dados numéricos , França , Guias como Assunto/normas , Setor de Assistência à Saúde/economia , Setor de Assistência à Saúde/legislação & jurisprudência , Humanos , Lactente , Recém-Nascido , Reembolso de Seguro de Saúde , Controle de Qualidade , Padrões de Referência , Fatores de Tempo
10.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S37-S43, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32861600

RESUMO

OBJECTIVES: The aim of this study was to evaluate peri- and post-operative complications related to cochlear implantations. We searched for risk factors predicting these complications and analyzed the complications in the youngest and most elderly. STUDY DESIGN: Retrospective analysis of cochlear implant patients. MATERIALS AND METHODS: All patients who underwent cochlear implantation in France between January 2012 and December 2016 were anonymized and registered in the EPIIC database. This population included 3483 adults and 2245 children. Their demographic and surgical data and their incidence of peri- or post-operative complications, including their severity, whether major or minor, were all indicated. RESULTS: The global complication rate was 6.84%. The risk of complication was higher in initial implantation versus reimplantation (P<0.0001). The risk was also higher for bilateral implantation versus unilateral (P<0.0001). Complications were more frequent for patients with cochlear malformation (P=0.002). There was no difference in complication rates across age groups; babies under 1 year old, and the elderly over 80 and even over 90, did not have more complications than the rest of the population. Patients treated in the daily care unit had no more complications than those who were hospitalized for one night or more (P=0.64). CONCLUSION: Cochlear implantation is a safe technique with a low incidence of complications. The absence of increased risk in patients at the extremes of the age spectrum justifies offering this solution to all, without age limitation.


Assuntos
Implante Coclear/efeitos adversos , Perda Auditiva/reabilitação , Complicações Intraoperatórias/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Sistema de Registros/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Cóclea/anormalidades , Implante Coclear/métodos , Hospital Dia/estatística & dados numéricos , França/epidemiologia , Perda Auditiva/etiologia , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Lactente , Pessoa de Meia-Idade , Reoperação/efeitos adversos , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
11.
Science ; 225(4658): 188-91, 1984 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-17837936

RESUMO

The effects of electron beam emissions from Spacelab were recorded with onboard diagnostic instruments. The variation of the Spacelab-shuttle potential with respect to the ambient plasma near the scientific air lock was investigated. Data on the waves and instabilities triggered by the electron beams are discussed. Within the electron gyrofrequency and electron plasma frequency range, strong signals were detected by both electric and magnetic antennas during the beam emissions. The frequencies of the emitted waves were compared to the characteristic plasma frequencies to enable mode identification.

12.
Rhinology ; 46(2): 125-30, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18575014

RESUMO

BACKGROUND: Nasal Polyposis (NP) is defined as a chronic inflammatory disease of sinonasal mucosa leading to diffuse formation of benign polyps. Although family histories are frequently suggested in medical literature, no specific study focused on this point has been reported. The purpose of this study is to determine whether a hereditary factor could be implied for NP in a family where several members were affected. We included 99 members of this family. METHODS: All patients were assessed for conditions known to be associated with the development or presence of NP. Concerning NP, patients were screened with a validated questionnaire and selected patients had a medical examination by an Ear, Nose and Throat practitioner. RESULTS: Thirteen patients had a personal history of NP without asthma, aspirin intolerance, Churg Strauss syndrome, cystic fibrosis, Young's syndrome, bare lymphocyte syndrome, or primary ciliary dyskinesia. Within this family, 19.7% of those older than 17 years were affected by NP, as compared with the national French prevalence of 2.1%. CONCLUSIONS: Regarding the pedigree, we discuss different modes of inheritance. The presence of consanguineous unions in this family suggests the possibility of a common ancestor and thus a recessive autosomal mode of inheritance.


Assuntos
Consanguinidade , Padrões de Herança/genética , Pólipos Nasais/genética , Doenças dos Seios Paranasais/genética , Adolescente , Adulto , Criança , Feminino , França , Ligação Genética/genética , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/mortalidade , Pólipos Nasais/patologia , Doenças dos Seios Paranasais/mortalidade , Doenças dos Seios Paranasais/patologia , Linhagem
13.
J Clin Invest ; 64(4): 1118-29, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-90057

RESUMO

A nonspecific opsonin function has been ascribed to human alpha 2 HS glycoprotein. Its serum level has been shown to be decreased in trauma patients. Recent studies from this laboratory revealed a heterogeneity among the products obtained in the course of the preparation of the protein. To date, no definitive agreement existed with regard to a molecular homogeneous entity of alpha 2 HS glycoprotein (Ba-alpha 2 glycoproteins). The purpose of the current work was to study the variations in serum level of alpha 2 HS in patients suffering from an acute inflammatory process of bacterial etiology and to determine whether a decrease in alpha 2 HS was accompanied by the appearance of fragments of this protein in the serum. A method of preparing alpha 2 HS was thus developed, using an immune absorbent as a final purification step. In an intermediary step of the preparation, alpha 2 HS was found to bind zinc when metal chelate affinity chromatography was employed. Immunologically and physico-chemically pure alpha 2 HS was obtained. The protein consists of a unique polypeptide chain of about 50,000 daltons and has a unique amino-terminal residue, alanine. However, the protein maintained its molecular integrity with difficulty, and spontaneous fragments ranging from 30,000 to less than 10,000 daltons were produced in some of the preparations. No major modification in the molecular structure of the protein was noted in the sera of subjects suffering from an acute inflammatory process. Serum level of alpha 2 HS and alpha 1 antitrypsin (AT)was determined in 23 patients. When the acute-phase (AP-)reactant alpha 1 AT was increased (difference with normal mean greater than +2 or +3 SD), the sera showed a large decrease in alpha 2 HS (difference with normal mean less than -2 or -3 SD). The serum level of alpha 2 HS, albumin, alpha 2 macroglobulin, and of positive AP-reactants, orosomucoidinal study of seven patients. The results were submitted to a principal components analysis. Alpha 2 HS showed a negative correlation with the AP-reactants alpha 1 AT, orosomucoid, and haptoglobin (P less than 0.05) and a positive correlation with albumin (P less than 0.05); these findings indicate that alpha 2 HS is a negative AP-reactant. In addition, analysis of the principal components confirms thestrong analogy between alpha 2 HS and albumin and indicates that serum level behavior of the AP-reactants during the course of the disease closely depends on the protein studied.


Assuntos
Proteínas Sanguíneas/isolamento & purificação , alfa-Macroglobulinas/metabolismo , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Imunodifusão , Imunoeletroforese , Masculino , Peso Molecular , alfa-Macroglobulinas/isolamento & purificação
14.
Ann Otolaryngol Chir Cervicofac ; 124(1): 33-40, 2007 Mar.
Artigo em Francês | MEDLINE | ID: mdl-17336916

RESUMO

The conventional hearing aid has benefited from the progress made in electronic miniaturization and digital signal processing. The prescriber should be familiar with these improvements, the anatomic and acoustic limitations related to hearing aids, the possibilities of surgical rehabilitation, as well as the indications for other auditive rehabilitation techniques (bone conduction hearing, middle ear implant, and cochlear implant). A hearing aid should be prescribed within a precise context taking into account patient history, clinical examination, audiometric testing, and choice of the device. Optimal management of a hearing device for a child should be conducted within an adapted network including a specialized ENT physician, audiophonology, a qualified hearing prosthetist, a speech therapist, etc.).


Assuntos
Auxiliares de Audição , Adaptação Fisiológica , Audiometria , Condução Óssea , Transtornos da Audição/terapia , Humanos , Miniaturização , Processamento de Sinais Assistido por Computador , Localização de Som
15.
Biochim Biophys Acta ; 668(2): 235-45, 1981 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-7225409

RESUMO

Isoelectric focusing in polyacrylamide gel was used to reveal the two alpha 1-acid glycoprotein populations separated by affinity chromatography on Con A-Sepharose from human purified alpha 1-acid glycoprotein, whole normal serum and sera from patients undergoing an acute inflammatory process. The concanavalin A non-reactive peak had a lower isoelectric point than did the concanavalin A reactive peak. Moreover, crossed immunoaffinity electrophoresis with free concanavalin A revealed three alpha 1-acid glycoprotein populations (concanavalin A reactive, weakly and non-reactive). A significant difference was observed between the patterns of normal and of inflammatory sera, since the concanavalin A reactive fraction was enhanced during the inflammatory process. These results suggest a variation in relative ratios of the different types of peripheral oligosaccharide branches in the alpha 1-acid glycoprotein populations.


Assuntos
Inflamação/sangue , Orosomucoide/isolamento & purificação , Cromatografia de Afinidade , Concanavalina A , Humanos , Focalização Isoelétrica , Ponto Isoelétrico
16.
Biochim Biophys Acta ; 1398(1): 1-8, 1998 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-9602019

RESUMO

The human alpha2-HS glycoprotein (A2HS) and rat phosphoprotein of Mr 63000 (pp63) are homologous plasma proteins and members of the fetuin superfamily. A2HS is involved in important functions such as inhibition of the tyrosine kinase activity of the insulin receptor, regulation of calcium metabolism and osteogenesis as well as protease inhibitory activity. We report an analysis of the 5' transcription control region (4 kb) of the A2HS gene. Its most proximal 300 nt display a very potent transcriptional activity. The latter is likely accounted for by C/EBP and NF1 binding sites that are conserved from the human A2HS gene to the rat pp63 gene. In contrast, these human and rat genes appear to largely diverge beyond their proximal promoter.


Assuntos
Proteínas Sanguíneas/genética , Regulação Enzimológica da Expressão Gênica , Sequências Reguladoras de Ácido Nucleico , Sequência de Bases , DNA , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Transcrição Gênica , alfa-2-Glicoproteína-HS
17.
Biochim Biophys Acta ; 439(2): 274-91, 1976 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-821533

RESUMO

The inter H-H cysteinyl peptides and the localization of the J-chain were studied in a human F(c)5mu-like fragment. The latter was found to be built up by non-covalent association of molecular forms of 140 000, 95 000 and 70 000 dalton subunits. The trimeric, dimeric and monomeric forms were obtained from gradual reduction by dithiothreitol of the major component of 140 000 daltons, thus confirming the tetrameric nature of this subunit. The latter was found to result from the association of both components of the 70 000 dalton subunit, with the participation of the inter H-H subunit bridge. Structural analysis of the labelled peptides obtained by partial reduction and alkylation showed the presence of the intersubunit disulfide bridge and of the inter heavy-heavy chain bridge of the C-terminal region, and the absence of the heavy-heavy chain bridge of the hinge region. The sequence of these peptides is identical to the sequences of the corresponding peptides of normal mmu-chains. The J-chain, which was covalently linked to this F(c)5mu-like fragment, was found to be predominantly associated within the 95 000 dalton subunit. The results showed that the J-chain was linked in the protein as a "clasp" within a single subunit and not between two subunits.


Assuntos
Fragmentos Fc das Imunoglobulinas , Cadeias J de Imunoglobulina , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Sítios de Ligação , Dissulfetos/análise , Eletroforese em Gel de Poliacrilamida , Humanos , Imunodifusão , Substâncias Macromoleculares , Peso Molecular , Pepsina A , Fragmentos de Peptídeos/análise , Ligação Proteica , Púrpura Hiperglobulinêmica/imunologia , Coelhos/imunologia , Tripsina
18.
Circulation ; 100(5): 541-6, 1999 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-10430769

RESUMO

BACKGROUND: Preconditioning with brief periods of ischemia protects the coronary endothelium against acute and chronic reperfusion injury, but the mechanisms of this endothelial protection remain unknown. We hypothesized that preconditioning protects endothelial cells through a decreased production of endothelial adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1), leading to a lesser adhesion of neutrophils to the endothelium. METHODS AND RESULTS: Cultured rat aortic endothelial cells were subjected to 6-hour anoxia followed by various durations of reoxygenation. Preconditioning was induced by 1-hour anoxia and 1-hour reoxygenation. ICAM-1 gene expression was measured by polymerase chain reaction, and the percentage of cells expressing ICAM-1 was assessed by confocal laser fluorescence microscopy. Anoxia/reoxygenation increased expression of ICAM-1, with a peak occurring after 6 hours of reoxygenation for mRNA and 9 hours for protein. Preconditioning prevented the increase in ICAM-1. Similar reductions were observed with the free radical scavenger N-2 mercaptopropionyl glycine (MPG). The inhibitory effect of preconditioning on ICAM-1 expression was abolished by an inhibitor of protein kinase C, an inhibitor of nitric oxide synthesis, and by MPG but was not affected by an adenosine receptor antagonist. Finally, both preconditioning and MPG partially prevented the increased adhesion of human neutrophils to reoxygenated endothelial cells. CONCLUSIONS: Preconditioning prevented reoxygenation-induced, free radical-mediated expression of ICAM-1 by a mechanism involving activation of protein kinase C and production of nitric oxide and free radicals, and this is associated with a lesser adhesion of neutrophils to endothelial cells. Such prevention of neutrophil adhesion may contribute to the protective effect of preconditioning against reperfusion-induced endothelial injury.


Assuntos
Endotélio Vascular/fisiopatologia , Hipóxia/fisiopatologia , Molécula 1 de Adesão Intercelular/biossíntese , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Neutrófilos/fisiologia , Animais , Aorta/citologia , Adesão Celular , Células Cultivadas , Primers do DNA , Endotélio Vascular/metabolismo , Ativação Enzimática , Radicais Livres/metabolismo , Regulação da Expressão Gênica , Hipóxia/metabolismo , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Óxido Nítrico/biossíntese , Reação em Cadeia da Polimerase , Proteína Quinase C/metabolismo , Ratos , Ratos Wistar
19.
Mol Immunol ; 19(1): 27-37, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7078556

RESUMO

Charge shift electrophoresis and crossed hydrophobic interaction immuno-electrophoresis were used to demonstrate the presence of hydrophobic sites in the human C3 molecule. C3b and C3d were true amphiphilic proteins that could bind to hydrophobic surfaces. To the contrary, native C3, that presented the characteristics of amphiphilic proteins upon charge shift electrophoresis, did not bind to hydrophobic surfaces. These results suggested that the hydrophobic sites were located in the internal part of the C3 molecule and they were exposed in the external part when C3 was activated. The action of chaotropes on C3 was studied in detail and showed that the hydrophobic sites protected the thiolester bond (present in the labile site) from hydrolysis by water and thereby preserved the biological properties of native C3.


Assuntos
Complemento C3 , Sítios de Ligação , Dicroísmo Circular , Detergentes , Eletroforese , Hemólise , Humanos , Fragmentos de Peptídeos , Conformação Proteica , Desnaturação Proteica , Solubilidade , Relação Estrutura-Atividade , Temperatura
20.
Mol Immunol ; 29(7-8): 983-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1386144

RESUMO

The biosynthesis of alternative regulatory complement protein factor H was investigated using both an in vivo rat model and an in vitro rat hepatocyte culture system, and compared to that of C3 component. Subcutaneous injection of a single dose of 20 micrograms of recombinant murine tumor necrosis factor-alpha (rmTNF-alpha) had no effect on factor H liver mRNA levels, while it increased C3 mRNA levels. In correlation with this, serum factor H levels remained unchanged after rmTNF-alpha injection, whereas C3 levels were increased. In contrast in vitro studies showed that rmTNF-alpha had no effect on factor H and C3 expression by rat hepatocytes. Recombinant human interleukin-1 alpha (rhIL-1 alpha) did not alter the expression of factor H, whereas it increased C3 expression, and recombinant human interleukin-6 (rhIL-6) stimulated expression of both proteins. This study shows that TNF-alpha is not directly responsible for the increased levels of factor H observed in vivo during induced inflammation in the rat. Its in vivo effect on C3 secretion might be secondary to the TNF-alpha-induced release of IL-1 and/or IL-6.


Assuntos
Complemento C3/metabolismo , Proteínas Inativadoras do Complemento C3b/metabolismo , Fígado/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Células Cultivadas , Fator H do Complemento , Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Interleucina-1/farmacologia , Interleucina-6/farmacologia , Fígado/citologia , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Terebintina/farmacologia
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