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1.
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
2.
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
3.
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
4.
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
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: 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
7.
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
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 ; 136(4): 273-279, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31072727

RESUMO

OBJECTIVES: Fabry disease (FD) is an X-linked inherited lysosomal storage disease. It is a multisystem pathology that can include ENT disorders. The aim of the present study was to investigate the cochleovestibular manifestations of FD, in order to show the importance of screening and systematic ENT evaluation. MATERIAL AND METHODS: A single-center retrospective study included 14 male and 23 female FD patients. Hearing impairment was defined as hearing loss greater than the 90th percentile for at least one frequency. Vestibular impairment was defined by lateral semicircular canal dysfunction. Age, ongoing enzyme replacement therapy (ERT) and organic (renal, cardiac and cerebrovascular) complications were used as severity markers. RESULTS: Hearing impairment was found in 62.6% of cases, mostly at high frequencies, and was associated with age, ERT, and cardiac and cerebrovascular disorder. It affected 46.7% of asymptomatic adult patients. Vestibular impairment was found in 56% of cases, associated with age; it affected two-thirds of ERT patients, more than 60% of patients with organic complications, and 50% of asymptomatic adult patients. CONCLUSIONS: More than half of patients had ENT involvement. All FD patients should undergo early ENT screening for diagnostic, prognostic and therapeutic purposes. Systematic complete ENT follow-up with auditory and vestibular evaluation should be performed regularly, even for heterozygous women.


Assuntos
Doença de Fabry/complicações , Adolescente , Adulto , Fatores Etários , Idoso , Limiar Auditivo , Doenças Cardiovasculares/complicações , Criança , Surdez/complicações , Surdez/diagnóstico , Terapia de Reposição de Enzimas , Doença de Fabry/terapia , Feminino , Perda Auditiva/complicações , Perda Auditiva/diagnóstico , Humanos , Ataque Isquêmico Transitório/complicações , Masculino , Pessoa de Meia-Idade , Nistagmo Patológico/complicações , Nistagmo Patológico/diagnóstico , Proteinúria/complicações , Proteinúria/diagnóstico , Insuficiência Renal/complicações , Insuficiência Renal/diagnóstico , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Zumbido/complicações , Zumbido/diagnóstico , Vertigem/complicações , Vertigem/diagnóstico , Adulto Jovem
10.
Eur Ann Otorhinolaryngol Head Neck Dis ; 135(1): 63-65, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28760617

RESUMO

INTRODUCTION: Liposarcoma of the hypopharynx is extremely rare, as only 28 cases have been reported in the literature. The cardinal symptom of liposarcoma is progressively worsening dysphagia. CASE REPORT: The authors report the case of a 71-year-old man who presented with dysphagia, marked weight loss over several weeks and an episode of exteriorization of a solid mass from the mouth during an episode of vomiting. Imaging revealed a fat density intra-oesophageal mass. Panendoscopy and upper gastrointestinal endoscopy visualized the pedunculated tumour in the left piriform sinus, which was able to be exteriorized via the mouth. The tumour was then resected endoscopically at its hypopharyngeal insertion pedicle. Histological examination of the operative specimen concluded on well-differentiated benign liposarcoma. DISCUSSION: Well-differentiated liposarcoma is the most common form of liposarcoma, but is only exceptionally reported in the hypopharynx. The main symptoms are related to compression of adjacent structures. Imaging findings are nonspecific. Only histological examination can distinguish liposarcoma from other benign oesophageal tumours. Standard treatment consists of wide, complete resection, which is not always possible in the neck. Long-term follow-up of these patients is essential in order to rapidly detect recurrence.


Assuntos
Neoplasias Hipofaríngeas/patologia , Neoplasias Hipofaríngeas/cirurgia , Laringoscopia , Lipossarcoma/patologia , Lipossarcoma/cirurgia , Idoso , Diagnóstico Diferencial , Humanos , Laringoscopia/métodos , Masculino , Resultado do Tratamento
11.
Bioorg Med Chem Lett ; 11(17): 2319-23, 2001 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-11527723

RESUMO

The novel phosphotyrosine (pTyr) mimetic 4'-carboxymethyloxy-3'-phosphonophenylalanine (Cpp) has been designed and incorporated into a series of nonpeptide inhibitors of the SH2 domain of pp60(c-Src) (Src) tyrosine kinase. A 2.2 A X-ray crystal structure of 1a bound to a mutant form of Lck SH2 domain provides insight regarding the structure-activity relationships and supports the design concept of this new pTyr mimetic.


Assuntos
Benzamidas/química , Benzamidas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Organofosfonatos/química , Organofosfonatos/farmacologia , Fosfotirosina/química , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Domínios de Homologia de src/efeitos dos fármacos , Animais , Sítios de Ligação , Reabsorção Óssea , Cristalografia por Raios X , Dentina/efeitos dos fármacos , Desenho de Fármacos , Inibidores Enzimáticos/metabolismo , Espectroscopia de Ressonância Magnética , Mimetismo Molecular , Mutação , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/química , Proteínas Proto-Oncogênicas pp60(c-src)/genética , Coelhos , Relação Estrutura-Atividade
12.
J Comb Chem ; 2(4): 305-13, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10891096

RESUMO

Using a novel, solid-phase parallel synthetic route and a computational docking program, a series of phosphorylated nonpeptides were generated to determine their structure-activity relationships (SAR) for binding at the SH2 domain of pp60src (Src). A functionalized benzoic acid intermediate was attached to solid support via Rink amide linkage, which upon acid cleavage generated the desired benzamide template-based nonpeptides in a facile manner. Compounds were synthesized using a combination of solid- and solution-phase techniques. Purification using reversed-phase, semipreparative HPLC allowed for quantitative SAR studies. Specifically, this work focused on functional group modifications, in a parallel fashion, designed to explore hydrophobic binding at the pY+3 pocket of the Src SH2 domain.


Assuntos
Benzamidas/síntese química , Sítios de Ligação , Proteínas Proto-Oncogênicas pp60(c-src)/química , Domínios de Homologia de src , Benzamidas/química , Cristalografia por Raios X , Desenho de Fármacos , Fosforilação , Relação Estrutura-Atividade
13.
J Med Chem ; 42(20): 4088-98, 1999 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-10514279

RESUMO

A series of 1,2,4-oxadiazole analogues has been shown to be potent and selective SH2 inhibitors of the tyrosine kinase ZAP-70, a potential therapeutic target for immune suppression. These compounds typically are 200-400-fold more potent than the native, monophosphorylated tetrapeptide sequences. When compared with the high-affinity zeta-1-ITAM peptide (Ac-NQL-pYNELNLGRREE-pYDVLD-NH(2), wherein pY refers to phosphotyrosine) some of the best 1,2, 4-oxadiazole analogues are approximately 1 order of magnitude less active. This series of compounds displays an unprecedented level of selectivity over the closely related tyrosine kinase Syk, as well as other SH2-containing proteins such as Src and Grb2. Gel shift studies using a protein construct consisting only of C-terminal ZAP-70 SH2 demonstrate that these compounds can effectively engage this particular SH2 domain.


Assuntos
Inibidores Enzimáticos/síntese química , Oxidiazóis/síntese química , Proteínas Tirosina Quinases/antagonistas & inibidores , Domínios de Homologia de src , Inibidores Enzimáticos/química , Precursores Enzimáticos/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular , Modelos Moleculares , Oxidiazóis/química , Relação Estrutura-Atividade , Quinase Syk , Proteína-Tirosina Quinase ZAP-70
14.
J Biol Chem ; 273(20): 12325-31, 1998 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9575185

RESUMO

As long as the threat of human immunodeficiency virus (HIV) protease drug resistance still exists, there will be a need for more potent antiretroviral agents. We have therefore determined the crystal structures of HIV-1 protease in complex with six cyclic urea inhibitors: XK216, XK263, DMP323, DMP450, XV638, and SD146, in an attempt to identify 1) the key interactions responsible for their high potency and 2) new interactions that might improve their therapeutic benefit. The structures reveal that the preorganized, C2 symmetric scaffolds of the inhibitors are anchored in the active site of the protease by six hydrogen bonds and that their P1 and P2 substituents participate in extensive van der Waals interactions and hydrogen bonds. Because all of our inhibitors possess benzyl groups at P1 and P1', their relative binding affinities are modulated by the extent of their P2 interactions, e.g. XK216, the least potent inhibitor (Ki (inhibition constant) = 4.70 nM), possesses the smallest P2 and the lowest number of P2-S2 interactions; whereas SD146, the most potent inhibitor (Ki = 0.02 nM), contains a benzimidazolylbenzamide at P2 and participates in fourteen hydrogen bonds and approximately 200 van der Waals interactions. This analysis identifies the strongest interactions between the protease and the inhibitors, suggests ways to improve potency by building into the S2 subsite, and reveals how conformational changes and unique features of the viral protease increase the binding affinity of HIV protease inhibitors.


Assuntos
Fármacos Anti-HIV/química , Inibidores da Protease de HIV/química , Protease de HIV/química , Azepinas/química , HIV-1/enzimologia , Ligação de Hidrogênio , Conformação Molecular , Ureia/análogos & derivados , Ureia/química , Ureia/farmacologia
15.
J Med Chem ; 41(9): 1446-55, 1998 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-9554878

RESUMO

Comparison of the high-resolution X-ray structures of the native HIV-1 protease and its complexes with the inhibitors suggested that the enzyme flaps are flexible. The movement at the tip of the flaps could be as large as 7 A. On the basis of this observation, cyclic cyanoguanidines have been designed, synthesized, and evaluated as HIV-1 protease (PR) inhibitors. Cyclic cyanoguanidines were found to be very potent inhibitors of HIV-1 protease. The choice of cyclic cyanoguanidines over cyclic guanidines was based on the reduced basicity of the former. X-ray structure studies of the HIV PR complex with cyclic cyanoguanidine demonstrated that in analogy to cyclic urea, cyclic cyanoguanidines also displace the unique structural water molecule. The structure-activity relationship of the cyclic cyanoguanidines is compared with that of the corresponding cyclic urea analogues. The differences in binding constants of the two series of compounds have been rationalized using high-resolution X-ray structure information.


Assuntos
Fármacos Anti-HIV , Guanidinas , Inibidores da Protease de HIV , Protease de HIV/metabolismo , HIV-1/efeitos dos fármacos , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Fármacos Anti-HIV/metabolismo , Fármacos Anti-HIV/farmacologia , Linhagem Celular , Cristalografia por Raios X , Guanidinas/síntese química , Guanidinas/química , Guanidinas/metabolismo , Guanidinas/farmacologia , Protease de HIV/química , Inibidores da Protease de HIV/síntese química , Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/metabolismo , Inibidores da Protease de HIV/farmacologia , HIV-1/enzimologia , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Relação Estrutura-Atividade , Ureia/análogos & derivados , Ureia/química
16.
J Med Chem ; 39(18): 3514-25, 1996 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-8784449

RESUMO

High-resolution X-ray structures of the complexes of HIV-1 protease (HIV-1PR) with peptidomimetic inhibitors reveal the presence of a structural water molecule which is hydrogen bonded to both the mobile flaps of the enzyme and the two carbonyls flanking the transition-state mimic of the inhibitors. Using the structure-activity relationships of C2-symmetric diol inhibitors, computed-aided drug design tools, and first principles, we designed and synthesized a novel class of cyclic ureas that incorporates this structural water and preorganizes the side chain residues into optimum binding conformations. Conformational analysis suggested a preference for pseudodiaxial benzylic and pseudodiequatorial hydroxyl substituents and an enantiomeric preference for the RSSR stereochemistry. The X-ray and solution NMR structure of the complex of HIV-1PR and one such cyclic urea, DMP323, confirmed the displacement of the structural water. Additionally, the bound and "unbound" (small-molecule X-ray) ligands have similar conformations. The high degree of preorganization, the complementarity, and the entropic gain of water displacement are proposed to explain the high affinity of these small molecules for the enzyme. The small size probably contributes to the observed good oral bioavailability in animals. Extensive structure-based optimization of the side chains that fill the S2 and S2' pockets of the enzyme resulted in DMP323, which was studied in phase I clinical trials but found to suffer from variable pharmacokinetics in man. This report details the synthesis, conformational analysis, structure-activity relationships, and molecular recognition of this series of C2-symmetry HIV-1PR inhibitors. An initial series of cyclic ureas containing nonsymmetric P2/P2' is also discussed.


Assuntos
Inibidores da Protease de HIV/síntese química , Ureia/síntese química , Animais , Inibidores da Protease de HIV/farmacologia , Humanos , Conformação Molecular , Relação Estrutura-Atividade , Ureia/química , Ureia/farmacologia
17.
Chem Biol ; 3(4): 301-14, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8807858

RESUMO

BACKGROUND: Effective HIV protease inhibitors must combine potency towards wild-type and mutant variants of HIV with oral bioavailability such that drug levels in relevant tissues continuously exceed that required for inhibition of virus replication. Computer-aided design led to the discovery of cyclic urea inhibitors of the HIV protease. We set out to improve the physical properties and oral bioavailability of these compounds. RESULTS: We have synthesized DMP 450 (bis-methanesulfonic acid salt), a water-soluble cyclic urea compound and a potent inhibitor of HIV replication in cell culture that also inhibits variants of HIV with single amino acid substitutions in the protease. DMP 450 is highly selective for HIV protease, consistent with displacement of the retrovirus-specific structural water molecule. Single doses of 10 mg kg-1 DMP 450 result in plasma levels in man in excess of that required to inhibit wild-type and several mutant HIVs. A plasmid-based, in vivo assay model suggests that maintenance of plasma levels of DMP 450 near the antiviral IC90 suppresses HIV protease activity in the animal. We did identify mutants that are resistant to DMP 450, however; multiple mutations within the protease gene caused a significant reduction in the antiviral response. CONCLUSIONS: DMP 450 is a significant advance within the cyclic urea class of HIV protease inhibitors due to its exceptional oral bioavailability. The data presented here suggest that an optimal cyclic urea will provide clinical benefit in treating AIDS if it combines favorable pharmacokinetics with potent activity against not only single mutants of HIV, but also multiply-mutant variants.


Assuntos
Azepinas/síntese química , Azepinas/farmacologia , Inibidores da Protease de HIV/síntese química , Inibidores da Protease de HIV/farmacologia , HIV-1/enzimologia , Ureia/análogos & derivados , Administração Oral , Animais , Azepinas/química , Azepinas/farmacocinética , Cristalografia por Raios X , Resistência Microbiana a Medicamentos/genética , Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/farmacocinética , HIV-1/fisiologia , Humanos , Infusões Intravenosas , Camundongos , Microscopia Eletrônica , Solubilidade , Ureia/síntese química , Ureia/química , Ureia/farmacocinética , Ureia/farmacologia , Replicação Viral/efeitos dos fármacos
18.
Pharm Res ; 13(2): 227-33, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8932441

RESUMO

PURPOSE: The effects of structural modifications on the membrane permeability of angiotensin II (Ang II) receptor antagonists and the usefulness of in vitro and in situ intestinal absorption models in predicting in vivo absorption or bioavailability were investigated. METHODS: Intestinal permeability was determined in vitro using Caco-2 cell monolayers and in situ using a perfused rat intestine method. Several physicochemical parameters were either measured or computed, and correlated with intestinal permeation. RESULTS: Permeation coefficients (Pa) across Caco-2 cell monolayers correlated well with both in situ absorption rate constants (ka) and in vivo bioavailability or % absorption. For these Ang II antagonists, Pa values larger than 3 x 10(-6) cm sec-1 and in situ ka values of 2 x 10(-4) min-1 cm-1 or above were associated with good in vivo absorption. Structural modifications at the R5 position, where a COOH group was substituted with either a CHO or CH2OH group, enhanced the permeability of the Ang II receptor antagonists up to 100-fold. There were good correlations between permeability and log P(octanol/buffer), log PHPLC, charge, solvation/desolvation energy and assigned hydrogen bonding potential. CONCLUSIONS: The correlations obtained in this study indicate that both the Caco-2 cell model and the in situ perfused rat intestine could be used to predict intestinal absorption in vivo. Structural modifications of the Ang II antagonists had a significant impact on the intestinal permeability. Charge, solvation energy, and hydrogen bonding are predominant determinants of intestinal permeability and oral bioavailability of these compounds.


Assuntos
Antagonistas de Receptores de Angiotensina , Indóis/farmacocinética , Absorção Intestinal/fisiologia , Mesilatos/farmacocinética , Peptídeos Cíclicos/farmacocinética , Piridinas/farmacocinética , Tetrazóis/farmacocinética , Animais , Disponibilidade Biológica , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacocinética , Células CACO-2/metabolismo , Permeabilidade da Membrana Celular/fisiologia , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Humanos , Concentração de Íons de Hidrogênio , Imidazóis/química , Imidazóis/farmacocinética , Técnicas In Vitro , Indóis/química , Losartan , Masculino , Mesilatos/química , Octanóis/química , Peptídeos Cíclicos/química , Piridinas/química , Ratos , Ratos Sprague-Dawley , Solubilidade , Relação Estrutura-Atividade , Tetrazóis/química
19.
Science ; 263(5145): 380-4, 1994 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-8278812

RESUMO

Mechanistic information and structure-based design methods have been used to design a series of nonpeptide cyclic ureas that are potent inhibitors of human immunodeficiency virus (HIV) protease and HIV replication. A fundamental feature of these inhibitors is the cyclic urea carbonyl oxygen that mimics the hydrogen-bonding features of a key structural water molecule. The success of the design in both displacing and mimicking the structural water molecule was confirmed by x-ray crystallographic studies. Highly selective, preorganized inhibitors with relatively low molecular weight and high oral bioavailability were synthesized.


Assuntos
Azepinas/química , Desenho de Fármacos , Inibidores da Protease de HIV/química , Administração Oral , Animais , Azepinas/metabolismo , Azepinas/farmacocinética , Azepinas/farmacologia , Sítios de Ligação , Disponibilidade Biológica , Linhagem Celular , Cristalografia por Raios X , Cães , Avaliação Pré-Clínica de Medicamentos , Protease de HIV/química , Protease de HIV/metabolismo , Inibidores da Protease de HIV/metabolismo , Inibidores da Protease de HIV/farmacocinética , Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Peso Molecular , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Ureia , Replicação Viral/efeitos dos fármacos
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