Switchable luminescent probes using resonance energy transfer

Understanding the molecular basics of recognition events in chemistry is crucial for a wide range of disciplines. Luminescence spectroscopy is an appealing way of obtaining information on molecular-scale recognition events, as sensitive, realtime detection and subnanometer spatial resolution can be achieved. Measurements in biological media are generally difficult because of the interference from the sample and the non-zero background. Resonance energy transfer (RET) between a luminescent donor and acceptor (D-A) is possible when excitation of the D is followed by energy transfer to A, that emits at increased wavelengths. Molecules that undergo RET triggered by the presence of a target molecule would allow a specific signal to be identified, as emission would occur only in the presence of the species of interest. Due to the increased emission wavelengths, interference with sample autofluorescence is avoided. The synthesis of donor-acceptor-quencher (D-A-Q) triads, equipped with coumarin donors, nucleoside quenchers, and organic or lanthanide acceptors, that are able to undergo triggered RET will be presented

Greater Tuberosity Fractures after RTSA: A Matched Group Analysis

Periprosthetic fractures, such as acromial and spine fractures, are known complications following implantation of reverse shoulder arthroplasty (RTSA). The entity of greater tuberosity fractures (GTF) has rarely been studied in the literature. The purpose of this study was to analyze the outcome of postoperative greater tuberosity fractures after RTSA compared to a matched control group. The main findings of this study are that a GTF after RTSA is associated with worse clinical outcome scores (mean absolute CS 50 ± 19 (p = 0.032); SSV 63% ± 26 (p = 0.022); mean force 1 kg ± 2 kg (p = 0.044)) compared with the control group (mean absolute CS 62 ± 21; SSV 77% ± 29; mean force 2 kg ± 2 kg). In terms of postoperative range of motion, the fracture group was significantly worse in terms of external rotation (17° ± 19° vs. 30° ± 19° (p = 0.029)). Internal rotation, flexion, as well as abduction of the shoulder appear to be unaffected (internal rotation GTF 4 ± 2, control group 5 ± 3 (p = 0.138); flexion GTF 102° ± 28°, control group 114° ± 27° (p = 0.160); abduction GTF 109° ± 42°, control group 120° ± 39° (p = 0.317))

Csont anyagtulajdonságainak megfelelő anyagmodellek előállítása additív gyártástechnológiákkal

Az additív technológiák ugrásszerű fejlődése a felhasználási területek bővülését is eredményezte. Egyre gyakoribb, hogy a bonyolult geometriával rendelkező orvosi implantátumokat valamely felépítő gyártástechnológiával állítjuk elő. Fontos azonban vizsgálni, hogy az így előállított implantátum hogyan viselkedik terhelés hatására, megfelelő teherbírással rendelkezik-e, illetve milyen mértékben képes együttműködni a környezetével. Ehhez ismerni kell az eredeti csont terhelés hatására kialakuló viselkedését. A viselkedés jellegét döntően befolyásolják az adott csont, csonttípus anyagjellemzői, melyek többnyire valamilyen mértékű anizotropiával rendelkeznek, valamint a csontra ható várható igénybevételek. Az implantátumok fejlesztésének egyik fő célja, hogy azok a várható igénybevételek hatására, hasonló jelleggel és mértékkel deformálódjanak, mint az eredeti csont. Ezt a megfelelő topológia kialakításával, valamint a gyártás során használt anyagok helyes megválasztásával lehet elérni. További lehetőség, hogy a gyártástechnológiai paraméterek segítségével befolyásolhatjuk az anyagjellemzőket, pl. az orientációs hatás felhasználásával közelíthetjük a csont anyagjellemzőit. Jelen tanulmányban egy femur fiziológiás terhelés és oldalirányú esés hatására vonatkozó terhelhetőségi viszonyait vizsgáljuk. Ezt vetjük össze egy FDM technológiájú 3D nyomtató által, különböző gyártási paraméterekkel elérhető anyagjellemzőkkel

Return to Play After Surgical Treatment of High-Grade Acromioclavicular Joint Injuries in the Australian Football League

Background Acromioclavicular joint (ACJ) injuries are the second most common upper limb injuries in the Australian Football League (AFL); however, there is little evidence on the return-to-sport results after surgical stabilization of the ACJ in this sporting population. Purpose To investigate the return-to-sport time, on-field performance, and patient-reported outcomes in a series of professional AFL players after undergoing ACJ stabilization. Study Design Case series; Level of evidence, 4. Methods We conducted a retrospective case series of all AFL players who had undergone open twin-tailed dog-bone ACJ stabilization by a single surgeon between September 2013 and April 2017. Outcome measures included time to return to sport, on-field performance indicators (handballs, tackles, kicks, and AFL Fantasy and Supercoach scores), the Nottingham Clavicle Score, Oxford Shoulder Score, and the Specific Acromioclavicular Score. Patient-reported outcomes were evaluated at a minimum follow-up of 12 months. Results Of 13 senior listed AFL players who underwent twin-tailed dog-bone surgery, 9 players were included. Mean follow-up was 24.8 months (range, 5-41 months) postoperatively. Mean return-to-sport time was 8.6 weeks for injuries that occurred within the season. The number of kicks, marks, handballs, and tackles as well as AFL Supercoach and Fantasy scores did not significantly change after surgery (P > .05). Outcome measures showed a high level of patient satisfaction after surgery, with a mean Nottingham Clavicle Score of 92.2, Oxford Shoulder Score of 47.7, and the Specific Acromioclavicular Score of 7.5. Conclusion In a collective of professional AFL players with ACJ injury, our twin-tailed dog-bone technique revealed return to competitive play could be achieved at a mean of 8.6 weeks without compromising on-field performance or patient-reported pain, function, and satisfaction

Vinculación Wizeline, diseño de sistemas

ITESO, A.C

Experimental Investigation of the Shear Modulus in the Case of Pure Tensile Test

In this paper, the authors determine the shear modulus using a pure tensile test without the application of pure shear external load. In order to validate the computer-aided theoretical model, a measurement setup was designed and built by the authors. A theoretical model was realized by finite element model in order to simulate the torsion effect exerted by a pure shear mode. The authors have validated the theoretical and experimental results using a new and innovative photostress measurement

Vinculación Wizeline, diseño de sistemas

ITESO, A.C

Reverse Total Shoulder Arthroplasty for Proximal Humeral Fractures and Sequalae Compared to Non-Fracture Indications: A Matched Cohort Analysis of Outcome and Complications

BACKGROUND: With the increase in utility and popularity of the reverse total shoulder arthroplasty (RTSA) within the last decades, indications for RTSA have expanded. As well as the established indications such as cuff tear arthropathy and massive irreparable rotator cuff tears, RTSA for complex proximal humeral fractures in elderly patients has been proven to be a reliable treatment option. METHODS: A prospectively enrolled RTSA database of 1457 RTSAs implanted between September 2005 and November 2020 was reviewed. Patients treated with RTSA for a complex proximal humerus fracture and fracture sequalae (F-RTSA) were 1:1 matched with a group of patients who were treated electively with RTSA for indications other than a fracture (E-RTSA). Matching criteria included sex, age, length of follow-up and body mass index. Evaluation after a minimum of 2 years follow-up included evaluation of the absolute and relative Constant-Murley score (aCS; rCS), subjective shoulder value (SSV), range of motion (ROM) assessment and complications. RESULTS: Each of the matched cohorts comprised 134 patients with a mean follow-up of 58 ± 41 months for the fracture group and 58 ± 36 months for the elective group. The mean age for both groups was 69 ± 11 years in the F-RTSA and 70 ± 9 years for the E-RTSA group. There were no significant differences in clinical outcome measures including aCS, rCS and SSV (p > 0.05). There was a significant difference in mean active external rotation with 20° ± 18° in the F-RTSA group compared with 25° ± 19° in the E-RTSA group (p = 0.017). The complication rate was not significantly different, with 41 complications in 36 shoulders in the F-RTSA and 40 complications in 32 shoulders in the E-RTSA group (p = 0.73). The main complication for the F-RTSA group was dislocation of the greater tuberosity (6%), whereas acromial fractures (9%) were the leading complication in the E-RTSA group. There was also no significant difference in revision rate comparing F-RTSA with E-RTSA (10% vs. 14%; p = 0.25). CONCLUSIONS: RTSA for complex proximal humeral fractures and its sequalae leads to a comparable clinical outcome as that for patients treated electively with RTSA for indications other than fracture. There was, however, a significant difference in active external rotation, with inferior rotation in patients undergoing RTSA for fracture. This valuable information can help in requesting informed consent of patients with proximal humeral fractures

Acromial Morphology and Its Relation to the Glenoid Is Associated with Different Partial Rotator Cuff Tear Patterns

The pathogenesis of subacromial impingement syndrome is controversially discussed. Assuming that bursal sided partial tears of the supraspinatus tendons are rather the result of a direct subacromial impact, the question arises whether there is a morphological risk configuration of the acromion and its spatial relation to the glenoid. Patients who underwent arthroscopic repair of either a partial articular supraspinatus tendon avulsion (PASTA) or bursal-sided supraspinatus tear (BURSA) were retrospectively allocated to two groups. Various previously described and new omometric parameters on standard anteroposterior and axial shoulder radiographs were analyzed. We hypothesized that acromial shape and its spatial relation to the glenoid may predispose to a specific partial supraspinatus tendon tear pattern. The measurements included the critical shoulder angle (CSA), the acromion index (AI), Bigliani acromial type and the new short sclerotic line, acromioclavicular offset angle (ACOA), and AC offset. The ratio length/width of acromion and the medial acromial offset were measured on axial radiographs. A total of 73 patients were allocated to either PASTA (n = 45) or BURSA (n = 28). The short sclerotic line showed a statistically significant difference between PASTA and BURSA (16.2 mm versus 13.1 mm, p = 0.008). The ratio acromial width/length was statistically significant (p = 0.021), with BURSA having slightly greater acromial length (59 vs. 56 mm). The mean acromial offset was 42.9 mm for BURSA vs. 37.7 mm for PASTA (p = 0.021). ACOA and AC offset were both higher for BURSA, without reaching statistical significance. The CSA did not differ significantly between PASTA and BURSA (33.73° vs. 34.56°, p = 0.062). The results revealed an association between a narrow acromial morphology, increased medial offset of the acromion in relation to the glenoid, and the presence of a short sclerotic line in the anteroposterior radiograph in bursal-sided tears of the supraspinatus tendon. Assuming that bursal-sided tears are rather the result of a direct conflict of the tendon with the undersurface of the acromion, this small subgroup of patients presenting with impingement syndrome might benefit from removing a harming acromial spur