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1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 139(1): 21-27, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34140263

ABSTRACT

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).


Subject(s)
Audiology , Cochlear Implants , Hearing Aids , Otolaryngology , Speech Perception , Adult , Humans , Speech
2.
B-ENT ; 6 Suppl 15: 49-50, 2010.
Article in English | MEDLINE | ID: mdl-21305924

ABSTRACT

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.


Subject(s)
Nasal Bone/surgery , Osteotomy/methods , Rhinoplasty/methods , Humans
3.
B-ENT ; 2(1): 39-42, 2006.
Article in English | MEDLINE | ID: mdl-16676847

ABSTRACT

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.


Subject(s)
Cartilage/transplantation , Pharynx/surgery , Ribs/transplantation , Velopharyngeal Insufficiency/surgery , Adult , Humans , Male , Plastic Surgery Procedures , Transplantation, Autologous , Treatment Outcome , Velopharyngeal Insufficiency/complications , Voice Disorders/etiology
4.
Unfallchirurg ; 106(2): 97-101, 2003 Feb.
Article in German | MEDLINE | ID: mdl-12624682

ABSTRACT

Between October 1996 and January 1999,29 patients (f:16,m:13,age: 22-86) with fractures of the lateral tibial plateau were operated on arthroscopic,fluoroscopic control or were treated with open reduction and internal fixation. 15 of them were retrospective and 14 prospective analysed. The metaphyseal defect after elevation of the depressed fragment was augmented in 11 cases with autologous spongeous bone grafting,in 9 cases with biodegradable bone cement (Norian SRS). Augmentation was unnecessary in 9 cases. The results according to the Lysholm score and the radiological results were good or excellent. Concerning the kind of augmentation no difference was noted. In the Norian SRS-group the duration of postoperative treatment was shorter than in the other group. The duration of partial weight bearing was shorter too. The results of the present study suggest that an injectable calcium phosphate cement may be a competent material for augmentation in lateral tibial plateau fractures because of the application form and the initial high mechanical stability.


Subject(s)
Bone Cements/therapeutic use , Calcium Phosphates/therapeutic use , Fracture Fixation, Internal/methods , Knee Injuries/surgery , Tibial Fractures/surgery , Adult , Aged , Aged, 80 and over , Biodegradation, Environmental , Bone Transplantation , Female , Humans , Knee Injuries/diagnostic imaging , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Prospective Studies , Radiography , Retrospective Studies , Tibial Fractures/diagnostic imaging
5.
Unfallchirurg ; 106(1): 20-7, 2003 Jan.
Article in German | MEDLINE | ID: mdl-12552389

ABSTRACT

QUESTION: This retrospective study presents results after conservative and operative treatment of thoracolumbar fractures as function of its localization. METHODOLOGY: In 2 years 70 patients with A1/A2 fracture were conservatively treated, 38 patients with A3/B/C injury were treated by internal fixtor. For evaluation 3 vertebral sections(Th5-10,Th11-L2,L3-5)were defined. Follow-up took place 1 year after implant removal or end of conservative treatment. RESULTS: The correction-loss was highest in thoracic, lowest in lumbar region. After conservative therapy,correction-loss was located to 3/4 in vertebra itself, after operative treatment especially in adjacent disc spaces. There was no general correlation to complaints. CONCLUSION: In consequence of these results A1/A2-fractures in the upper thoracic spine (15 degrees will be stabilized anteriorly, in other regions functional treated. A3-fractures of thoracic spine and thoracolumbar junction will be operated from anterior, in lower lumbar spine (>L3) from dorsal. B- and C-injuries should be instrumented with a combined dorsoventral procedure.


Subject(s)
Internal Fixators , Lumbar Vertebrae/injuries , Postoperative Complications , Spinal Fractures/surgery , Spinal Fractures/therapy , Thoracic Vertebrae/injuries , Adolescent , Adult , Aged , Data Interpretation, Statistical , Female , Follow-Up Studies , Humans , Kyphosis/etiology , Male , Middle Aged , Retrospective Studies , Time Factors
6.
Arthroscopy ; 17(8): 892-7, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11600991

ABSTRACT

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.


Subject(s)
Arthroscopy/methods , Collateral Ligaments/surgery , Posterior Cruciate Ligament/surgery , Tendons/transplantation , Absorbable Implants , Bone Screws , Collateral Ligaments/diagnostic imaging , Humans , Osteotomy/methods , Posterior Cruciate Ligament/diagnostic imaging , Radiography , Suture Techniques
7.
Unfallchirurg ; 104(9): 852-9, 2001 Sep.
Article in German | MEDLINE | ID: mdl-11572128

ABSTRACT

Between March 1997 and October 1999 thirty-one patients with displaced proximal humeral fractures were treated with crossed screw osteosynthesis. Insertion of the screws was realized by using a deltoideo-pectoral approach placing the screws anteriorly and posteriorly in a crossed manner from the distal fragment into the humeral head. Additionally, in all two-part-fractures a tension band was applied. In all three-part-fractures, the greater tuberosity was reattached by additional screws. In 21 patients (14 female, 7 male, median age 62 years, 18-86) a clinical and radiological follow-up (median 18 months, 10-29) was obtained. Fractures were classified as two-part-fractures in 10 patients and as three-part-fractures in 11 patients. According to the Constant-Score, "excellent" and "good" results were achieved in 15 patients, "moderate" results were found in 3 patients. However, in 3 patients results were only "poor" (1 two-part-, 2 three-part-fractures). The complication rate was 29% (premature hardware removal due to head perforation in 3 cases; humeral head necrosis necessitating prosthetic replacement in 2 patients; secondary displacement in 1 case). Crossed screw osteosynthesis represents an justified alternative in the surgical treatment of displaced proximal humeral fractures permitting early functional therapy.


Subject(s)
Bone Screws , Fracture Fixation, Internal/instrumentation , Shoulder Fractures/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Device Removal , Female , Humans , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Postoperative Complications/surgery , Radiography , Reoperation , Shoulder Fractures/diagnostic imaging , Treatment Outcome
8.
Zentralbl Chir ; 126(3): 205-10, 2001 Mar.
Article in German | MEDLINE | ID: mdl-11301886

ABSTRACT

Between 11/1989 and 6/1998 52 patients (10 m., 42 f., age median 72 years, 31-88) with proximal humeral fractures have been treated by conservative means (angulation of humeral head > 45 degrees and/or shaft displacement > 1 cm and displacement of greater tuberosity > 0.5 cm). In 37 patients (71%, 31 f., 6 m., age median 75 years, 36-88) a clinical and radiological follow-up could be obtained after median 20 months (3-93). According to the Neer-classification, subcapital 2-part fractures were found in 19 cases and 3-part fractures in 12 cases. 4-part fractures were diagnosed in 6 cases. By using the Constant-Score, the final result was scored "excellent" in 10 patients and "good" in 13 patients. In 7 patients each the results achieved were "moderate" or "poor". The underlying cause for the poor results was primarily due to persisting painful impairment in range of motion and loss of strength. Radiologically, persisting axial deviation was present in 23 cases, arthrosis in 14 patients and humeral head necrosis in 8 patients. Most commonly, poor functional and radiological results occurred in 4-part fractures. However, conservative therapy of displaced 2-part and 3-part fractures is a considerable therapeutical option since the final results are predominantly good. In contrast, due to the poor results after conservative therapy 4-part fractures should be treated surgically.


Subject(s)
Humeral Fractures/therapy , Shoulder Dislocation/therapy , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Time Factors
9.
Arch Orthop Trauma Surg ; 121(1-2): 31-7, 2001.
Article in English | MEDLINE | ID: mdl-11195115

ABSTRACT

Between January 1993 and December 1996, 41 patients with fracture dislocation of the elbow joint were treated in our department. In 28 patients (median age 46 years, range 15-77 years; 16 male, 12 female), a clinical and radiological follow-up was obtained after median 34 months (range 12-59 months). In addition to the humero-ulnar dislocation, isolated fractures were present in 13 patients and combined fractures in 15 (all with involvement of the radial head). Primary neurological deficits were found in 7 and open fractures in 3 patients. In 7 patients, primary definitive surgical therapy was carried out by open reduction and internal fixation. A two-step surgical management (initial closed reduction and immobilization, 5 patients with external fixator, 7 with plaster; secondary open surgical procedure) was performed in 12 and conservative treatment in 9 patients. According to the Leipzig Elbow Score, taking subjective, clinical and radiological criteria into consideration, 4 patients achieved 'excellent' and 5 patients a 'good' result. Ten patients were scored 'moderate' and 9 'poor'. The rate of secondary complications necessitating revision was 36%. Poor results were primarily caused by extensive initial soft-tissue damage, delayed definitive surgical therapy, and ectopic heterotopic ossification. In contrast, fracture localization and degree of arthrosis were not of significant importance for the final outcome. In fracture dislocations, the goal is a primary definitive surgical treatment aiming for early postoperative physiotherapy.


Subject(s)
Elbow Injuries , Fracture Fixation/instrumentation , Fracture Fixation/methods , Joint Dislocations/therapy , Radius Fractures/therapy , Adolescent , Adult , Aged , Casts, Surgical , External Fixators , Female , Follow-Up Studies , Fracture Fixation/adverse effects , Humans , Joint Dislocations/classification , Joint Dislocations/complications , Joint Dislocations/diagnostic imaging , Joint Dislocations/physiopathology , Length of Stay/statistics & numerical data , Male , Middle Aged , Pain, Postoperative/etiology , Physical Therapy Modalities , Postoperative Care , Radiography , Radius Fractures/classification , Radius Fractures/complications , Radius Fractures/diagnostic imaging , Radius Fractures/physiopathology , Range of Motion, Articular , Severity of Illness Index , Surveys and Questionnaires , Treatment Outcome
10.
Acta Otorhinolaryngol Belg ; 54(2): 109-13, 2000.
Article in English | MEDLINE | ID: mdl-10892499

ABSTRACT

The different varieties of choanal polyps are reviewed by the authors according to their implantation pedicle. Their histology, possible pathogenesis, the various symptoms, steps in the diagnostic procedure and differential diagnoses are also described. Finally, the various modes of treatment are discussed, focussing in particular on the surgical methods and the new possibilities offered by developments in the field of endoscopy.


Subject(s)
Nasal Polyps/diagnosis , Nasal Polyps/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Diagnosis, Differential , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Paranasal Sinus Neoplasms/diagnosis , Tomography, X-Ray Computed
11.
Acta Otorhinolaryngol Belg ; 54(2): 139-50, 2000.
Article in English | MEDLINE | ID: mdl-10892503

ABSTRACT

Six centers cooperated in a retrospective study on endoscopic surgical resection of Papillomas of the nose and paranasal sinuses in order to assess both the efficiency and the safety of this kind of surgical approach. From 1991 till march 2000, 87 cases of Papillomas resections under--at least partially--endoscopic control were gathered, among which 85 were Inverted Papillomas (IP), 2 were Exophytic Papilloma (EP) and one was IP coexisting with Collumnar Cell Papilloma (CCP). Malignant transformation was found out in 3 cases of IP. Regarding the 85 patients with IP demographics are as follows: 61 males, 24 females, with a mean age of 58.4 years (STDV: 13.96) in a range from 27 to 92 years. The mean follow-up was of 41.9 months with range of 1-120 months. Fifteen recurrences occurred that were treated by revision surgery either under endoscopic control or by limited external approach. The mean time for recurrences to occur was 8.07 months with range of 1-24 months. The three patients with malignant transformation underwent postoperative radiation therapy. All of the patients are free of recurrence, however for some of them the follow-up is too short to definitely assess their free of disease status. The role of modern diagnostic tools in medical imaging--CAT and MRI--in order to assess clearly the limits of the tumors and to enhance the efficiency and the safety in the choice of a surgical approach is pointed out. The stress is put on the need for radical excision under endoscopic control which can be combined with the Caldwell-Luc transantral approach or with frontal trepanation for the cure of tumors impossible to be reached under endoscopic control only. Irrespective of the tumor extent and of the approaches that was used for excision a close endoscopic follow-up still remain mandatory, by trained surgeons, in the long term management of IP. Biopsies, CAT and/or MRI must be performed in any case with recurrence suspicion.


Subject(s)
Endoscopy/methods , Papilloma, Inverted/surgery , Paranasal Sinus Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Belgium/epidemiology , Catchment Area, Health , Diagnostic Errors , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/epidemiology , Neoplasm Recurrence, Local/surgery , Papilloma, Inverted/diagnosis , Papilloma, Inverted/epidemiology , Paranasal Sinus Neoplasms/diagnosis , Paranasal Sinus Neoplasms/epidemiology , Tomography, X-Ray Computed , Treatment Outcome
12.
Unfallchirurg ; 103(11): 999-1002, 2000 Nov.
Article in German | MEDLINE | ID: mdl-11142891

ABSTRACT

In a 32 years old professional handball layer, the micro-traumata typical of this game led to retropatellar cartilage lesion, which became sympthomatic following an distortion-impact trauma. Since the patient remains symptomatic after initial conservative treatment as well as arthroscopic chondroplastic, osteo-chondral transplantation was performed. There was a good functional result 6 months after surgery.


Subject(s)
Athletic Injuries/surgery , Bone Transplantation , Cartilage, Articular/injuries , Cartilage/transplantation , Joint Dislocations/surgery , Knee Injuries/surgery , Patella/injuries , Adult , Arthroscopy , Cartilage, Articular/surgery , Female , Humans , Patella/surgery , Reoperation , Transplantation, Autologous
13.
Chirurg ; 70(11): 1209-15, 1999 Nov.
Article in German | MEDLINE | ID: mdl-10591757

ABSTRACT

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.


Subject(s)
Fracture Fixation, Internal/methods , Hip Fractures/surgery , Pseudarthrosis/surgery , Biomechanical Phenomena , Hip Fractures/physiopathology , Humans , Pseudarthrosis/physiopathology , Reoperation , Weight-Bearing/physiology
14.
Eur Spine J ; 8(5): 346-53, 1999.
Article in English | MEDLINE | ID: mdl-10552316

ABSTRACT

INTRODUCTION: The latest open MRI technology allows to perform open and closed surgical procedures under real-time imaging. Before performing spinal trauma surgery preclinical examinations had to be done to evaluate the artifacts caused by the implants. METHODS: The MRT presented is a prototype developed by GE. Two vertically positioned magnetic coils are installed in an operation theater. By that means two surgeons are able to access the patient between the two coils. Numerous tests regarding the material of instruments and implants were necessary in advance. The specific size of the artifact depending on the pulse sequence and the positioning within the magnetic field had to be examined. RESULTS: The magnifying factors of the artifact in the spin echo sequence regarding titanium are between 1.7 and 3.2, depending on the direction of the magnetic vector. Regarding stainless steel they are between 8.4 and 8.5. In the gradient echo sequence the factors are between 7.5 and 7.7 for titanium and between 16.9 and 18.0 for stainless steel. The tip of an implant is imaged with an accuracy of 0 to 2 mm. Since September 1997 16 patients with unstable fractures of the thoracic and lumbar spine have been treated by dorsal instrumentation in the open MRI. Percutaneous insertion of the internal fixator has proven a successful minimally invasive procedure. The positioning of the screws in the pedicle is secure, the degree of indirect reduction of the posterior wall of the vertebral body can be imaged immediately. The diameter of the spinal canal can be determined in any plane. DISCUSSION AND CONCLUSION: The open MRI has proven useful in orthopedic and trauma surgery. The size and configuration of the artifacts caused by instruments and implants is predictable. Therefore exact positioning of the implants is achieved more easily. Dorsal instrumentation of unstable thoracolumbar fractures with a percutaneous technique has turned out safe and less traumatic under MR-imaging. Real-time imaging of soft tissue and bone in any plane improves security for the patient and allows the surgeon to work less invasively and more precisely.


Subject(s)
Magnetic Resonance Imaging , Spinal Fractures/surgery , Spine/pathology , Spine/surgery , Artifacts , Bone Screws , Equipment Design , Humans , Intraoperative Period , Lumbosacral Region , Magnetic Resonance Imaging/instrumentation , Minimally Invasive Surgical Procedures , Postoperative Complications , Postoperative Period , Stainless Steel , Thorax , Titanium
15.
Chirurg ; 69(11): 1178-87, 1998 Nov.
Article in German | MEDLINE | ID: mdl-9864622

ABSTRACT

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.


Subject(s)
Ankle Injuries/surgery , Bone Malalignment/surgery , Osteotomy/instrumentation , Tibial Fractures/surgery , Ankle Injuries/diagnostic imaging , Arthroscopes , Bone Malalignment/diagnostic imaging , Bone Plates , Bone Screws , External Fixators , Humans , Postoperative Complications/diagnostic imaging , Postoperative Complications/surgery , Radiography , Reoperation , Tibial Fractures/diagnostic imaging
16.
Chirurg ; 69(11): 1230-7, 1998 Nov.
Article in German | MEDLINE | ID: mdl-9864635

ABSTRACT

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.


Subject(s)
Shoulder Dislocation/rehabilitation , Adolescent , Adult , Aged , Female , Follow-Up Studies , Humans , Immobilization , Male , Middle Aged , Neurologic Examination , Radiography , Recurrence , Shoulder Dislocation/diagnostic imaging , Treatment Outcome
17.
J Med Chem ; 41(26): 5167-76, 1998 Dec 17.
Article in English | MEDLINE | ID: mdl-9857087

ABSTRACT

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.


Subject(s)
Narcotic Antagonists/chemical synthesis , Oligopeptides/chemical synthesis , Receptors, Opioid, delta/antagonists & inhibitors , Receptors, Opioid, mu/agonists , Tetrahydroisoquinolines , Animals , Binding, Competitive , Cell Line , Cerebellum/drug effects , Cerebellum/metabolism , Guinea Pigs , Ileum/drug effects , Ileum/physiology , In Vitro Techniques , Male , Mice , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Narcotic Antagonists/chemistry , Narcotic Antagonists/metabolism , Narcotic Antagonists/pharmacology , Oligopeptides/chemistry , Oligopeptides/metabolism , Oligopeptides/pharmacology , Prosencephalon/drug effects , Prosencephalon/metabolism , Protein Conformation , Radioligand Assay , Rats , Receptors, Opioid, delta/agonists , Structure-Activity Relationship , Vas Deferens/drug effects , Vas Deferens/physiology
18.
J Pept Res ; 49(4): 336-40, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9176817

ABSTRACT

The disulfide bridge pairing of Ac-AMP2, a 30-residue peptide isolated from the seeds of Amaranthus caudatus, is determined using a fast method involving enzymatic fragmentation followed by identification of the fragments with FAB mass spectrometry. The results confirm the location of the three disulfide bridges as previously established by NMR spectroscopy and molecular modelling.


Subject(s)
Anti-Infective Agents/chemistry , Peptide Fragments/chemistry , Peptides/chemistry , Seeds/chemistry , Amino Acid Sequence , Disulfides , Endopeptidases , Molecular Sequence Data , Spectrometry, Mass, Fast Atom Bombardment/methods
19.
J Med Chem ; 40(6): 990-5, 1997 Mar 14.
Article in English | MEDLINE | ID: mdl-9083489

ABSTRACT

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.


Subject(s)
Analgesics, Opioid/chemistry , Oligopeptides/chemistry , Opioid Peptides/chemistry , Receptors, Opioid, delta/agonists , Analgesics, Opioid/chemical synthesis , Analgesics, Opioid/metabolism , Analgesics, Opioid/pharmacology , Animals , Binding, Competitive , Brain/metabolism , Guinea Pigs , Ileum/drug effects , Magnetic Resonance Spectroscopy , Male , Mice , Muscle Contraction/drug effects , Oligopeptides/chemical synthesis , Oligopeptides/metabolism , Oligopeptides/pharmacology , Opioid Peptides/chemical synthesis , Opioid Peptides/metabolism , Opioid Peptides/pharmacology , Protein Binding , Protein Conformation , Rats , Receptors, Opioid, delta/metabolism , Vas Deferens/drug effects
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