Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Language
Publication year range
1.
Am J Sports Med ; 50(2): 321-326, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34935511

ABSTRACT

BACKGROUND: The Latarjet procedure involves initial dissection through a longitudinal split of the subscapularis tendon with only a final partial closure to accommodate the transferred coracoid bone. Furthermore, by transferring the coracoid bone block to the anterior glenoid, the surgeon completely alters the resting and dynamic route of the attached conjoint tendon. The eventual structural and functional integrity of the subscapularis and conjoint tendons is currently unknown. PURPOSE: To examine the structural and functional integrity of the subscapularis and the conjoint tendon after the Latarjet procedure at an 8-year average follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty patients with anterior shoulder instability at a mean age of 30 years (range, 19-50 years) underwent the open Latarjet procedure. Clinical examination at the final follow-up included quantitative isometric measurement of abduction and internal rotation strength compared with the nonoperative side. Patients were assessed via radiograph examination and preoperative computed tomography. Final position and healing of the transferred coracoid bone block were evaluated using standard radiographs. At follow-up, the subscapularis and conjoint tendon were evaluated via magnetic resonance imaging (MRI) with metal artifact reduction techniques and via ultrasound. RESULTS: Nineteen of the 20 shoulders remained stable at the final follow-up; there was 1 redislocation (5%) after 14 months. The mean Rowe score was 83 points (SD, 17.9 points), the mean Constant score was 85 points (SD, 8.1 points), and the Subjective Shoulder Value was 80% (SD, 18%). The mean abduction strength of the operative shoulder was 7.41 ± 2.06 kg compared with 8.33 ± 2.53 kg for the nonoperative side (P = .02). The mean internal rotation strength at 0° for the operative shoulder was 8.82 ± 3.47 kg compared with 9.06 ± 3.01 kg for the nonoperative side (P = .36). The mean internal rotation strength in the belly-press position for the operative shoulder was 8.12 ± 2.89 kg compared with 8.50 ± 3.03 kg (P = .13). Four of 20 shoulders showed mild tendinopathic changes of the subscapularis tendon but no partial or complete tear. One patient exhibited fatty degeneration Goutallier stage 1. Conjoint tendon was in continuity in all 20 shoulders on MRI scans. CONCLUSION: Abduction, but not internal rotation strength, was slightly reduced after the Latarjet procedure at a mean of 8 years of follow-up. The subscapularis tendon was intact based on ultrasound examination, and the conjoint tendon was intact based on MRI scans. Subscapularis muscle girth relative to the supraspinatus muscle remained intact from preoperative measurements based on MRI scans.


Subject(s)
Joint Instability , Shoulder Joint , Adult , Follow-Up Studies , Humans , Joint Instability/diagnostic imaging , Joint Instability/surgery , Rotator Cuff/diagnostic imaging , Rotator Cuff/surgery , Shoulder Joint/diagnostic imaging , Shoulder Joint/surgery , Tendons/diagnostic imaging , Tendons/surgery
2.
J Phys Chem A ; 119(1): 39-49, 2015 Jan 08.
Article in English | MEDLINE | ID: mdl-25474121

ABSTRACT

It is noted that, for a small series of 3,5-diacetyl-1,4-dihydrolutidine (DDL) derivatives and the corresponding Hantzsch esters, the presence of methyl groups at the 2,6-positions serves to extinguish fluorescence in solution but not in the solid state. Emission is weakly activated and affected by changes in solvent polarity. The latter situation arises because the optical transition involves intramolecular charge transfer. Calculations, both semiempirical and DFT, indicate that, in all cases, rotation of the carbonyl function is facile and that the dihydropyridine ring is planar. These calculations also indicate that the 2,6-methyl groups do not affect the generic structure of the molecule. It is proposed that illumination increases the molecular dipole moment and pushes electron density toward the carbonyl oxygen atom. Proton transfer can now occur from one of the methyl groups, leading to formation of a relatively low-energy, neutral intermediate, followed by a second proton transfer step that forms the enol. Reaction profiles computed for the ground-state species indicate that this route is highly favored relative to hydrogen transfer from the 4-position. The barriers for light-induced proton transfer are greatly reduced relative to the ground-state process but such large-scale structural transformations are hindered in the solid state. A rigid analogue that cannot form an enol is highly emissive in solution, supporting the conclusion that proton transfer is in competition to fluorescence in solution.


Subject(s)
Dihydropyridines/chemistry , Esters/chemistry , Protons , Molecular Structure , Photochemical Processes , Quantum Theory
3.
Org Lett ; 14(18): 4774-7, 2012 Sep 21.
Article in English | MEDLINE | ID: mdl-22958188

ABSTRACT

A Boranil fluorophore bearing a nitro-phenyl group has been selectively reduced to its anilino form and then successfully converted to amide, imine, urea, and thiourea derivatives which are fluorescent dyes. Its isolated isothiocyanate intermediate derivative was used in a model labeling experiment with Bovine Serum Albumin (BSA). The purified labeled-BSA exhibits strong luminescence (Φ(f) = 47%) in a phosphate buffer at pH = 7.4.


Subject(s)
Boron Compounds/chemical synthesis , Fluorescent Dyes/chemical synthesis , Boron Compounds/chemistry , Fluorescent Dyes/chemistry , Hydrogen-Ion Concentration , Isothiocyanates , Molecular Structure , Serum Albumin, Bovine/chemistry , Thiourea/chemistry , Urea/chemistry
4.
Org Lett ; 13(13): 3414-7, 2011 Jul 01.
Article in English | MEDLINE | ID: mdl-21648467

ABSTRACT

Complexation of a large variety of Anils (aniline-imines) with boron(III) precursors provides stable Boranils, some of which have been structurally characterized. Analysis of their optical properties reveals that the fluorescence stems from an intraligand charge transfer (ILCT) state with the best quantum yields reaching 90%. Chemistry on the Boranils allows grafting of photoactive modules acting as energy antennae for borondipyrromethene (Bodipy) and subphtalocyanine (SubPc) fluorophores.


Subject(s)
Boron Compounds/chemical synthesis , Fluorescent Dyes/chemical synthesis , Chelating Agents/chemistry , Models, Molecular , Molecular Structure
SELECTION OF CITATIONS
SEARCH DETAIL
...