Developing new host materials is crucial to enhance the performance of blue organic light‐emitting diodes (OLEDs), but achieving long operational lifetimes for OLEDs has been challenging. In this ...study, boron‐ and silane‐based electron transport–type (n‐type) host materials, 5,9‐dioxa‐13b‐boranaphtho3,2,1‐deanthracen‐7‐yltriphenylsilane (BO‐pSi) and 2,12‐bis(triphenylsilyl)‐5,9‐dioxa‐13b‐boranaphtho3,2,1‐deanthracene (BO‐2mSi), derived from boron‐ and oxygen‐based 5,9‐dioxa‐13b‐boranaphtho3,2,1‐deanthracene (DOBNA) are developed. The DOBNA derivatives are modified with a triphenylsilyl blocking group to alleviate intermolecular interactions arising from the planar structure of DOBNA. The DOBNA derivatives maintain high triplet energy even in the solid state and show thermally activated delayed fluorescence features with electron transport properties. BO‐pSi is used as an n‐type host and exhibits a long operational lifetime of ≈5000 h up to 50% of the initial luminance of blue phosphorescent OLEDs. Furthermore, BO‐2mSi demonstrates a high external quantum efficiency of 7.1%, a small full width at half maximum of 33 nm, and a pure‐violet color coordinate of (0.16, 0.02) while maintaining color purity even at high doping concentrations up to 50 wt%.
Boron‐ and silane‐based electron transport–type (n‐type) host materials are developed and they show alleviated intermolecular interactions and maintain high triplet energy even in the solid state. They demonstrate a long operational lifetime of ≈5000 h up to 50% of the initial luminance of blue phosphorescent organic light‐emitting diodes as a n‐type host.
Background:
In large-sized rotator cuff tears, tendon repair with incomplete footprint coverage is performed frequently as a way of tension-free or low-tension repair.
Purpose:
To compare clinical ...outcomes after arthroscopic repair of large-sized rotator cuff tears between patients with complete versus incomplete footprint coverage.
Study Design:
Cohort study; Level of evidence, 3.
Methods:
Among 297 patients who underwent arthroscopic surgery for a large-sized rotator cuff tear, we selected 58 patients (<50% coverage; mean age, 63.34 ± 6.8 years; 34 men and 24 women) with incomplete footprint coverage. Using propensity score matching, another 58 patients with complete footprint coverage (mean age, 63.4 ± 8.03 years; 34 men and 24 women) were selected after 1:1 matching for age, sex, and tear size—the main demographic and prognostic factors of outcomes after rotator cuff repair. Clinical outcomes were compared on magnetic resonance imaging or ultrasonography at minimum of 6 months postoperatively, and functional outcomes were compared using range of motion and pain visual analog scale; American Shoulder and Elbow Surgeons; Constant; University of California, Los Angeles; and Simple Shoulder Test scores at a minimum of 2 years postoperatively.
Results:
A total of 18 patients in the incomplete footprint coverage group (31.0%) and 20 patients in the complete footprint coverage group (34.5%) showed healing failure, with no significant difference between groups (P = .843). In addition, there were no differences in functional outcomes between groups (P > .05 for all).
Conclusion:
Whether the rotator cuff footprint was completely covered did not affect clinical outcomes in conventional arthroscopic repair of large-sized rotator cuff tears.
Cytosolic malate dehydrogenase (malate dehydrogenase 1, MDH1) plays pivotal roles in the malate/aspartate shuttle that might modulate metabolism between the cytosol and mitochondria. In this study, ...we investigated the role of MDH1 in osteoclast differentiation and formation. MDH1 expression was induced by receptor activator of nuclear factor kappa-B ligand (RANKL) treatment. Knockdown of MDH1 by infection with retrovirus containing MDH1-specific shRNA (shMDH1) reduced mature osteoclast formation and bone resorption activity. Moreover, the expression of marker genes associated with osteoclast differentiation was downregulated by shMDH1 treatment, suggesting a role of MDH1 in osteoclast differentiation. In addition, intracellular ATP production was reduced following the activation of adenosine 5′ monophosphate-activated protein kinase (AMPK), a cellular energy sensor and negative regulator of RANKL-induced osteoclast differentiation, in shMDH1-infected osteoclasts compared to control cells. In addition, the expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), a critical transcription factor of osteoclastogenesis, was decreased with MDH1 knockdown during RANKL-mediated osteoclast differentiation. These findings provide strong evidence that MDH1 plays a critical role in osteoclast differentiation and function via modulation of the intracellular energy status, which might affect AMPK activity and NFATc1 expression.
In this work, a design methodology to develop purely organic phosphorescent (POP) emitters was studied to improve the photoluminescence quantum yield (PLQY) and external quantum efficiency (EQE) of ...organic light-emitting diodes (OLEDs). The molecular design was directed to have a strong spin–orbit coupling through a phenoselenazine core for triggering phosphorescence and an expanded chromophore using an aromatic extended structure to enhance radiative transition probability. As a result, a 3-(9-phenyl-9H-carbazol-3-yl)-10-(p-tolyl)-10H-phenoselenazine (PSe3Cz) emitter achieved high PLQY of 50.2% and EQE of 13.2% in POPLEDs. The EQE of this work is one of the highest EQE values reported in heavy metal-free phosphorescent OLEDs.
Actin-binding LIM protein 1 (ABLIM1), a member of the LIM-domain protein family, mediates interactions between actin filaments and cytoplasmic targets. However, the role of ABLIM1 in osteoclast and ...bone metabolism has not been reported. In the present study, we investigated the role of ABLIM1 in the receptor activator of NF-κB ligand (RANKL)- mediated osteoclastogenesis. ABLIM1 expression was induced by RANKL treatment and knockdown of ABLIM1 by retrovirus infection containing Ablim1-specific short hairpin RNA (shAblim1) decreased mature osteoclast formation and bone resorption activity in a RANKL-dose dependent manner. Coincident with the downregulated expression of osteoclast differentiation marker genes, the expression levels of c-Fos and the nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), critical transcription factors of osteoclastogenesis, were also decreased in shAblim1-infected osteoclasts during RANKLmediated osteoclast differentiation. In addition, the motility of preosteoclast was reduced by ABLIM1 knockdown via modulation of the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/Akt/Rac1 signaling pathway, suggesting another regulatory mechanism of ABLIM1 in osteoclast formation. These data demonstrated that ABLIM1 is a positive regulator of RANKLmediated osteoclast formation via the modulation of the differentiation and PI3K/Akt/Rac1-dependent motility. BMB Reports 2018; 51(7): 356-361.
Background:
It remains unclear whether lateral joint space narrowing without severe cartilage loss before meniscal allograft transplantation (MAT) affects clinical outcomes and graft extrusion.
...Hypothesis:
Patients with greater preoperative joint space narrowing would show more graft extrusion, more osteoarthritis progression, and worse clinical outcomes than would those with less narrowing.
Study Design:
Case-control study; Level of evidence, 3.
Methods:
We retrospectively evaluated 61 patients who underwent lateral MAT and had a minimum follow-up of 4 to 5 years. The median preoperative joint space width (JSW) on Rosenberg view radiographs was used to classify patients into those with less joint space narrowing (JSW ≥3 mm; group A) and greater joint space narrowing (JSW <3 mm; group B). We compared differences between groups in terms of graft extrusion and articular cartilage loss (modified Outerbridge grade ≥3) on 1-year postoperative magnetic resonance imaging (MRI) scans and changes in JSW and clinical outcomes at the last follow-up.
Results:
There were 31 patients in group A and 30 patients in group B; the mean follow-up time for all patients was 64.4 ± 10.3 months. All patients showed a significant preoperative to postoperative improvement in outcome scores (P < .001 for all). The mean preoperative JSW was 3.8 ± 0.9 mm in group A and 2.3 ± 0.4 mm in group B (P < .001). In group B, there was more graft extrusion on postoperative MRI scans (3.0 ± 0.9 vs 1.9 ± 0.6 mm, respectively; P < .001) and a higher proportion of patients with pathological graft extrusion at final follow-up (43.3% vs 12.9%, respectively; P = .011) compared with group A. At 1 year postoperatively, cartilage loss grade ≥3 was observed at the lateral femoral condyle in 3.2% and 20.0% of patients in groups A and B (P = .053), respectively, and at the lateral tibial plateau in 3.2% and 30.0% of patients (P = .006), respectively. There were moderate correlations between graft extrusion and preoperative absolute JSW (r = –0.471; P < .001) and preoperative relative JSW (r = –0.428; P = .001).
Conclusion:
Patients with less preoperative joint space narrowing had less graft extrusion and cartilage loss on 1-year postoperative MRI scans, as well as better radiological and clinical outcomes at midterm follow-up, compared with patients with greater preoperative narrowing.
This study proposes a novel approach to develop highly efficient, narrow‐emitting violet materials based on boron and oxygen polycyclic aromatic hydrocarbon multiple resonance structure. Herein, ...B‐2OCz is developed by fusing indole with a 5,9‐dioxa‐13bboranaphtho3,2,1‐deanthracene (DOBNA) core to enhance its thermally activated delayed fluorescence (TADF) properties and molecular rigidity. On the other hand, the B‐2OCz‐Si is decorated with a bulky tetraphenylsilyl substituent. B‐2OCz‐Si exhibits exceptional features such as violet emission at 397 nm, a very small full width at half maximum of 16 nm, and 82% of photoluminescence quantum yield. The B‐2OCz‐Si devices achieve a high external quantum efficiency of over 15%, violet emission with a peak wavelength of 423 nm, and color coordinates of (0.156, 0.037). Furthermore, the B‐2OCz‐Si is used as an electron transport type host material for phosphorescent organic light‐emitting diodes (PhOLEDs), based on its high triplet energy and TADF properties. As compared to the conventional triazine based host materials, these newly developed DOBNA‐based materials display superior device lifetime performance. All these potential aspects corroborate that this new class of DOBNA‐based materials can work as a promising host material for PhOLEDs and violet‐emitting fluorescent devices.
Highly efficient, narrow‐emitting violet materials based on boron and oxygen polycyclic aromatic hydrocarbon multiple resonance structure achieve a high external quantum efficiency of over 15%, violet emission with a peak wavelength of 423 nm, and CIE chromaticity coordinates of (0.156, 0.037).
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