RESUMO
OBJECTIVES: This document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs. MATERIAL AND METHODS: The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. RESULTS: Eight tests of speech audiometry in noise can be used in France. CONCLUSION: To be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).
Assuntos
Audiologia , Implantes Cocleares , Auxiliares de Audição , Otolaringologia , Percepção da Fala , Adulto , Humanos , FalaRESUMO
The authors present their surgical experience with the management of patients with dorsum deformities using a precise technique: the external percutaneous approach. The indications for this technique have still not been set out very clearly in the rhinological textbooks or manuals, and so novices (and not only novices) have difficulty in understanding and applying it. We therefore try to systematise and clarify these indications in brief, together with the technical details, providing a comparison with another technique that is in very widespread use at present: the internal lateral osteotomy. Although the external percutaneous approach is not used very often--in our experience in 30% of cases only--we find the results very satisfactory and we recommend it when it is required by the anatomic conditions.
Assuntos
Osso Nasal/cirurgia , Osteotomia/métodos , Rinoplastia/métodos , HumanosRESUMO
The velopharyngeal sphincter is critical in enabling the functions of speaking and swallowing. Velopharyngeal insufficiency (VPI) results in hypernasal speech and nasal regurgitation. A frequent cause of VPI is congenital cleft palate, but otolaryngologists sometimes encounter iatrogenic VPI after surgery. Treatment of VPI with prostheses is often successful but not always well tolerated. Many surgical procedures have been proposed to correct palatal length or to enlarge the posterior pharyngeal wall. We report two cases in which autologous costochondral cartilage was used as implant augmentation. This approach is indicated and efficient when the velopharyngeal deficit is less than 5 mm. An autologous costochondral cartilage implant procedure is safe and reversible and can be expected to incite minimal host reaction.
Assuntos
Cartilagem/transplante , Faringe/cirurgia , Costelas/transplante , Insuficiência Velofaríngea/cirurgia , Adulto , Humanos , Masculino , Procedimentos de Cirurgia Plástica , Transplante Autólogo , Resultado do Tratamento , Insuficiência Velofaríngea/complicações , Distúrbios da Voz/etiologiaRESUMO
The conformation in water of antimicrobial protein 2 from Amaranthus caudatus (Ac-AMP2) was determined using 1H NMR, DIANA and restrained molecular modeling. Ac-AMP2 is a 30 amino acid residue, lectin-like protein that specifically binds to chitin, a polymer of beta-1,4-N-acetyl-D-glucosamine. After sequence specific resonance assignments, a total of 198 distance restraints were collected from 2D NOESY buildup spectra at 500 MHz at pH 2, supplemented by a 2D NOESY spectrum at 600 MHz. The location of the three previously unassigned disulfide bridges was determined from preliminary DIANA structures, using a statistical analysis of intercystinyl distances. The solution structure of Ac-AMP2 is presented as a set of 26 DIANA structures, further refined by restrained molecular dynamics using a simulated annealing protocol in the AMBER force field, with a backbone r.m.s.d. for the well defined Glu3-Cys28 segment of 0.69(+/-0.12) angstroms. The main structural element is an antiparallel beta-sheet from Met13 to Lys23 including a betaI-turn over Gln17-Phel8 with a beta bulge at Gly19. In addition, a beta'I turn over Arg6-Gly7, a beta'III turn over Ser11-Gly12 and a helical turn from Gly24 to Cys28 are identified. This structure is very similar to the equivalent regions of the X-ray structure of wheat germ agglutinin and the NMR structure of hevein.
Assuntos
Antifúngicos/química , Proteínas de Plantas/química , Plantas/química , Sequência de Aminoácidos , Sequência de Bases , Carboidratos/química , Dissulfetos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Estrutura Secundária de Proteína , Sementes/química , Homologia de Sequência de Aminoácidos , SoluçõesRESUMO
The interaction between Ac-AMP2, a lectin-like small protein with antimicrobial and antifungal activity isolated from Amaranthus caudatus, and N,N',N"-triacetyl chitotriose was studied using 1H NMR spectroscopy. Changes in chemical shift and line width upon increasing concentration of N,N',N"-triacetyl chitotriose to Ac-AMP2 solutions at pH 6.9 and 2.4 were used to determine the interaction site and the association constant Ka. The most pronounced shifts occur mainly in the C-terminal half of the sequence. They involve the aromatic residues Phe18, Tyr20 and Tyr27 together with their surrounding residues, as well as the N-terminal Val-Gly-Glu segment. Several NOEs between Ac-AMP2 and the N,N',N"-triacetyl chitotriose resonances are reported.
Assuntos
Espectroscopia de Ressonância Magnética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Trissacarídeos/química , Trissacarídeos/metabolismo , Sequência de Aminoácidos , Antifúngicos/química , Sítios de Ligação , Sequência de Carboidratos , Hidrogênio , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Proteínas de Plantas/farmacologia , Sementes/química , Homologia de Sequência de AminoácidosRESUMO
The conformations of three endothelin antagonists, a cyclic pentapeptide, a linear tripeptide and a linear hexapeptide, are compared by 1H NMR and molecular dynamics. The three analogues have a Leu and a DTrp side chain which are oriented parallel, and an acidic group next to the DTrp residue.
Assuntos
Temperatura Baixa , Endotelinas/antagonistas & inibidores , Espectroscopia de Ressonância Magnética , Sequência de Aminoácidos , Dados de Sequência Molecular , Oligopeptídeos/química , Peptídeos Cíclicos/química , Conformação ProteicaRESUMO
Two approaches to the design of very active and highly selective delta opioid peptides were used to obtain new deltorpin analogs with altered hydrophobic and stereoelectronic properties. Deltorphin I and II analogs were synthesized involving the substitution of Ile instead of Val at positions 5 and 6 in the address domain and 2-aminotetralin-2-carboxylic acid (Atc) instead of Phe in the message domain. The peptides were agonists in the subnanomolar range in the MVD assay and in the micromolar or higher range in the GPI assay, showing a very high selectivity for delta receptors. A very similar trend could be observed in radioreceptor binding assays in which selective tritiated opioid ligands were used. (R)- and (S)-Atc-deltoriphins exhibited similar Ki values in the binding assay, with almost complete loss of the stereospecificity of the binding. Conformational studies provided evidence for the little disturbance of the backbone conformational equilibrium when Phe3 is replaced by (S)- or (R)-Atc. The use of the Atc constraint gives additional evidence that, during its interaction with the delta receptor, the side chain of residue 3 adopts the trans conformation at chi 1.
Assuntos
Analgésicos Opioides/química , Oligopeptídeos/química , Peptídeos Opioides/química , Receptores Opioides delta/agonistas , Analgésicos Opioides/síntese química , Analgésicos Opioides/metabolismo , Analgésicos Opioides/farmacologia , Animais , Ligação Competitiva , Encéfalo/metabolismo , Cobaias , Íleo/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Oligopeptídeos/síntese química , Oligopeptídeos/metabolismo , Oligopeptídeos/farmacologia , Peptídeos Opioides/síntese química , Peptídeos Opioides/metabolismo , Peptídeos Opioides/farmacologia , Ligação Proteica , Conformação Proteica , Ratos , Receptores Opioides delta/metabolismo , Ducto Deferente/efeitos dos fármacosRESUMO
The delta-opioid antagonist H-Tyr-Tic-Phe-Phe-OH (TIPP-OH) or its C-terminal amide analogue was systematically modified topologically by substitution of each amino acid residue by all stereoisomers of the corresponding beta-methyl amino acid. The potency and selectivity (delta- vs mu- and kappa-opioid receptor) were evaluated by radioreceptor binding assays. Agonist or antagonist potency were assayed in the mouse vas deferens and in the guinea pig ileum. In the TIPP analogues containing L-beta-methyl amino acids the influence on delta-receptor affinity and on delta-antagonist potency is limited, the [(2S,3R)-beta-MePhe3]TIPP-OH analogue being among the most potent delta-antagonists reported. In the D-beta-methyl amino acid series, the [D-beta-MeTic2] analogues are delta-selective antagonists whereas [D-Tic2]TIPP-NH2 is a delta-agonist. NMR studies did not indicate any influence of the beta-methyl substituent on the conformation of the Tic residue. The [(2R,3S)-beta-MePhe3]TIPP-NH2 is a potent delta-agonist, its C-terminal carboxylic acid analogue being more delta-selective but displaying partial agonism in both the delta- and mu-bioassay. These results constitute further examples of a profound influence of beta-methyl substitution on the potency, selectivity, and signal transduction properties of a peptide.
Assuntos
Antagonistas de Entorpecentes/síntese química , Oligopeptídeos/síntese química , Receptores Opioides delta/antagonistas & inibidores , Receptores Opioides mu/agonistas , Tetra-Hidroisoquinolinas , Animais , Ligação Competitiva , Linhagem Celular , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Cobaias , Íleo/efeitos dos fármacos , Íleo/fisiologia , Técnicas In Vitro , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Antagonistas de Entorpecentes/química , Antagonistas de Entorpecentes/metabolismo , Antagonistas de Entorpecentes/farmacologia , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Oligopeptídeos/farmacologia , Prosencéfalo/efeitos dos fármacos , Prosencéfalo/metabolismo , Conformação Proteica , Ensaio Radioligante , Ratos , Receptores Opioides delta/agonistas , Relação Estrutura-Atividade , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/fisiologiaRESUMO
The molecular structure of (2S)-2-benzyl-3-(cis-hexahydro-2-isoindolinylcarbonyl) propionic acid (KAD-1229), a hypoglycemic drug of the meglitinide family, was studied by nuclear magnetic resonance (NMR) and molecular modeling. The results of the NMR experiments indicated that KAD-1229 existed in solution in the form of two stable conformers of equal population, called KADI and KADII in this paper. Three different molecular modelings were then applied: the classical molecular dynamics using the commercial Biosym and Hyperchem softwares and the Prot+ program, which is not based on a dynamical study but on a systematic conformational analysis of the molecule, which includes a term that allows the estimation of the hydrophobic interaction. The modeling results showed the following points. First, in contrast with classical molecular dynamics, which uses restraints from two-dimensional nuclear Overhauser effect (NOE) data, the Prot+ KAD structure provides conformations that support experimental NMR data without any external intervention. In the structures in agreement with NMR data, an important hydrophobic interaction between the phenyl cycle and the perhydroisoindole ring of KAD is observed. This interaction, which seems to play a role in the biological activity of the drug, is lost when no restraints are considered in classical molecular dynamics. Second, the difference between KADI and KADII arises mainly from slight distance geometric differences at the level of the perhydroisoindole and the phenyl rings.
Assuntos
Hipoglicemiantes/química , Indóis/química , Benzamidas/química , Benzamidas/farmacologia , Simulação por Computador , Hipoglicemiantes/farmacologia , Indóis/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/fisiologia , Isoindóis , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Prótons , Software , Soluções , Relação Estrutura-Atividade , TermodinâmicaRESUMO
The molecular structure of the steroids [1,2,5]oxadiazolo[3', 4':3,4]-5 alpha-pregn-16-en-20-one oxime, [1,2,5]oxadiazolo[3',4':3, 4':3,4]-5 alpha-pregn-16-en-20-one and [1,2,5]oxadiazole]3',4':3,4]-5 beta-pregn-16-en-20-one has been determined. The proton-proton distances in the solid state from previous crystallographic studies are compared with the corresponding distances from novel and previous solution NMR as well as from novel in vacuo modeling studies.
Assuntos
Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Pregnenos/química , Cristalização , Estrutura MolecularRESUMO
Arthroscopic-assisted simultaneous reconstruction of the posterior cruciate ligament (PCL) and the lateral collateral ligament (LCL) using hamstring tendon grafts is described. The femoral tunnel is drilled through an incision over the medial femoral condyle and the tibial tunnel through the same skin incision used for harvesting the tendon graft. PCL reconstruction is performed using a 4-strand hamstring tendon graft and absorbable screw fixation. The tendon of the semitendinosus muscle of the uninvolved knee is used as a lateral loop for LCL reconstruction. After pulling the transplant through the fibular head, femoral fixation of the loop is made with an absorbable screw.
Assuntos
Artroscopia/métodos , Ligamentos Colaterais/cirurgia , Ligamento Cruzado Posterior/cirurgia , Tendões/transplante , Implantes Absorvíveis , Parafusos Ósseos , Ligamentos Colaterais/diagnóstico por imagem , Humanos , Osteotomia/métodos , Ligamento Cruzado Posterior/diagnóstico por imagem , Radiografia , Técnicas de SuturaRESUMO
Pain is not always the leading symptom of a failed union. High primary stability often allows full weight bearing in spite of fracture instability. The difficult diagnosis of a pseudarthrosis is a reason for late intervention. Implant failure and implant breakage are typical signs of surgical underestimation. Finally, the diagnosis "pseudarthrosis" is a fluent one and is defined as a failed fracture healing despite implant stability. Recognition of biological and biomechanical failure, this demands correct evaluation of the global situation and extensive experience in revision surgery on the part of the surgeon.
Assuntos
Fixação Interna de Fraturas/métodos , Fraturas do Quadril/cirurgia , Pseudoartrose/cirurgia , Fenômenos Biomecânicos , Fraturas do Quadril/fisiopatologia , Humanos , Pseudoartrose/fisiopatologia , Reoperação , Suporte de Carga/fisiologiaRESUMO
The general aspects for the analysis of malalignment of the low tibial region in the three-dimensional space are discussed. Recommendations of clinical and radiological diagnostics prior to low tibial osteotomies are given. Closing wedge, opening wedge, dome-shaped, distraction, rotational and step-shaped osteotomies as well as combined procedures are described. The possibilities of these techniques are pointed out for malalignment after lower leg, pilon and ankle fractures, as well as after trauma of the distal epiphysis of the tibia. Arthroscopy of the ankle is an additional tool for detailed planning of the adequate surgical procedure. The importance of determining an early correction cannot be underestimated.
Assuntos
Traumatismos do Tornozelo/cirurgia , Mau Alinhamento Ósseo/cirurgia , Osteotomia/instrumentação , Fraturas da Tíbia/cirurgia , Traumatismos do Tornozelo/diagnóstico por imagem , Artroscópios , Mau Alinhamento Ósseo/diagnóstico por imagem , Placas Ósseas , Parafusos Ósseos , Fixadores Externos , Humanos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/cirurgia , Radiografia , Reoperação , Fraturas da Tíbia/diagnóstico por imagemRESUMO
Between January 1989 and March 1997, 175 patients with traumatic shoulder dislocation were treated by conservative means (median age 41 years, 39 F, 136 M). In 78 patients (17 F, 61 M) a clinical and radiological follow up (median 50 months, range 6-106) could be obtained. Additionally, a diagnostic ultrasound was carried out in all patients. The recurrence rate in the group younger than 30 years (G < 30; n = 35) was 86%; in the group older than 30 years (G > 30; n = 43) it was 21% (P < 0.05). Persisting neurological deficits were found in 6 patients (8%). According to the Rowe score, 16 patients (46%) of the G < 30 achieved excellent or good results, in the G > 30, 29 patients (67%). In 17% of cases, a glenohumeral arthrosis was diagnosed be radiological means. 18% had radiological signs of a previous fracture of the greater tuberosity. Hill-Sachs lesions were identified in 19% of cases. Rotator cuff tears were diagnosed in 9% by ultrasound. No relationship between the duration of immobilization and the recurrence rate was found (P = 0.95). The recurrence rate following primary shoulder dislocation depends primarily on the patients' age.
Assuntos
Luxação do Ombro/reabilitação , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Imobilização , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Radiografia , Recidiva , Luxação do Ombro/diagnóstico por imagem , Resultado do TratamentoRESUMO
Some vasculotensional diseases may be associated, at a certain point of their evolution, with occurrences of sudden deafness or of benign paroxysmal positional vertigo. It seems that the efficiency of the treatments of sudden deafness and benign paroxysmal positional vertigo is not modified by those associations of pathologies. On the other side, the search for anticochlear antibodies gives a positive result in 45% of the vasculotensional diseases. When the vasculotensional disease is associated with sudden deafness, this percentage increases. On the contrary, it is lower when the vasculotensional disease is associated with benign paroxysmal positional vertigo. The presence of anticochlear antibodies may lead to a corticotherapy in case of failure of the classical treatments.
Assuntos
Anticorpos/análise , Cóclea/imunologia , Perda Auditiva Súbita/imunologia , Doenças Vasculares/imunologia , Vertigem/imunologia , Perda Auditiva Súbita/tratamento farmacológico , Humanos , Doenças Vasculares/fisiopatologia , Doenças Vasculares/terapiaRESUMO
The shortened analogue of insulin, des-(B26-B30)-pentapeptide insulin, has been characterized by two-dimensional 1H NMR. The 1H resonance assignments and the secondary structure in water solution are discussed The results indicate that the secondary structure in solution is very similar to that reported for the crystalline state. A high flexibility of both A and B chains is observed. Of the two conformations seen in the 2-Zn insulin crystals and indicated as molecules 1 and 2 (Chinese nomenclature), the structure of the analogue is more similar to that of molecule 1.
Assuntos
Insulina/análogos & derivados , Sequência de Aminoácidos , Aminoácidos/análise , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Conformação Proteica , ÁguaRESUMO
We report the complete assignment of the 1H-nmr spectrum of beta-casomorphin-5 in DMSO-d6 solution. With a combination of one-dimensional, double quantum filtered correlated spectroscopy, homonuclear Hartmann-Hahn, and rotating frame nuclear Overhauser enhancement spectroscopy (ROESY) spectra, we were able to differentiate the four conformers originating from two Xxx-Pro bonds present in the sequence. Exchange peaks in the ROESY spectra confirmed the presence of four interchanging conformational isomers. Based on integrations, the relative populations of the four species were estimated, while characteristic sequential nuclear Overhauser enhancements (NOEs) were used to determine the orientation of the Xxx-Pro bonds. This orientation was also shown to correlate with the chemical shift changes for the alpha protons of both the Xxx and Pro residues. Finally, interresidue NOEs indicate conformational preferences for the aromatic side chains, especially in the all-trans conformer.
Assuntos
Endorfinas/química , Fragmentos de Peptídeos/química , Dimetil Sulfóxido , Isomerismo , Espectroscopia de Ressonância Magnética/métodos , Conformação ProteicaRESUMO
The influence of low temperature and high viscosity on the conformation of somatostatin and two of its analogues was investigated by 1H NMR in solution. The conformation of native somatostatin, a cyclic octapeptide agonist DC13-116 and a linear octapeptide agonist were compared in ethylene glycol at 303 K and in methanol at low temperature. The first goal of this study was to investigate if either low temperature or high viscosity is the more important for the reduction of the conformational freedom. Secondly we wanted to compare the amount of information concerning the conformation present in both solvents. A larger amount of NOESY cross-peaks is observed in ethylene glycol at room temperature compared to methanol at low temperature. This indicates that the raising of the viscosity is a more important factor in reducing the flexibility of peptides than the lowering of the temperature.
Assuntos
Etilenoglicóis/química , Metanol/química , Estrutura Secundária de Proteína , Somatostatina/análogos & derivados , Somatostatina/química , Sequência de Aminoácidos , Fenômenos Químicos , Físico-Química , Temperatura Baixa , Etilenoglicol , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligopeptídeos/química , Peptídeos Cíclicos/química , Conformação Proteica , Soluções , ViscosidadeRESUMO
The conformation of cyclosporin A (CsA), an undecapeptide with seven N-methylated amino acids, was studied in acetone at 193 K. Previous studies of the conformation of CsA in different solvents, in the cyclosporin-cyclophilin complex and in complexes with LiCl showed that the conformation of the free and the bound CsA are different. Differences were observed at the conformation of the MeLeu9-MeLeu10 peptide bond, which is cis in solution and trans in the complex, and in the orientation of the amide protons and the N-Me groups. By using acetone, which is a proton acceptor, we wanted to influence the orientation of the amide protons. In the conditions used in this study a new conformation is found, which differs as well from the one previously observed in solution as from the conformation observed in the complex. This conformation has a cis peptide bond between MeLeu9 and MeLeu10. The trans conformation of the peptide bond MeLeu9-MeLeu10, which is necessary for biological activity, was not induced. One of the amide protons is involved in an intramolecular H-bridge stabilising a beta-turn around Sar3MeLeu4, and three of the seven NMe groups are oriented to the centre of the molecule.