Osteolysis induced by chronic Gram-negative bacterial infection underlies many bone diseases such as osteomyelitis, septic arthritis, and periodontitis. Drugs that inhibit lipopolysaccharide ...(LPS)-induced osteolysis are critically needed for the prevention of bone destruction in infective bone diseases. In this study, we assessed the effect of puerarin, a natural isoflavone isolated from Pueraria lobata OHWI root, on LPS-induced osteoclastogenesis and bone loss. Our in vitro study showed that puerarin significantly inhibited LPS-induced osteoclast differentiation from osteoclast precursor RAW264.7 cells. The inhibition occurred through suppressing the production of osteoclast activating factor tumor necrosis factor (TNF)-α, interleukin (IL)-1β and prostaglandin E2 (PGE2), which led to down-regulating mRNA expression of osteoclastogenic genes including tartrate-resistant acid phosphatase (TRAP), cathepsin K and matrix metalloprotein 9 (MMP-9). Furthermore, LPS triggered activation of Akt in osteoclast precursor RAW264.7 cells, which was inhibited by puerarin treatment. In vivo, puerarin attenuated LPS-induced bone loss in a murine calvarial osteolysis model. Collectively, puerarin prevents LPS-induced osteoclast formation, function and bone loss, where the inhibition of Akt activation plays an important role. These findings provide evidences that puerarin might be beneficial as a promising candidate drug for the prevention and treatment of bacteria-induced bone destruction disease, and give new insights for understanding its possible mechanism.
Thermally activated delayed fluorescence (TADF) materials that exhibit simultaneously high photoluminescence quantum yield (PLQY), rapid reverse intersystem crossing (RISC), and a high horizontal ...transition dipole ratio are highly desirable for realizing high‐performance organic light‐emitting diodes (OLEDs). However, achieving this goal remains a formidable challenge due to the stringent molecular design principles involved. Herein, three highly efficient TADF materials based on lactam‐type electron‐acceptors are reported. The inherent rigidity and planar structure of lactam units, along with the ordered molecular arrangement in solid states, contribute to the reduction of nonradiative decay and the high horizontal transition dipole ratio in the optimized TADF emitters. Moreover, through precise control of the alignment of the lowest excited states by adjusting the charge transfer strength, the rate constants for reverse intersystem crossing (kRISC) are dramatically boosted. Consequently, the two optimized emitters exhibit outstanding merits of ultra‐high PLQYs (98% and 99%), high horizontal transition dipole ratios (91% and 87%), and fast RISC (kRISC ≈ 1.7 × 106 s−1). Thanks to these merits, the doped OLEDs achieve excellent performance. The top‐performing device achieve a maximum external quantum efficiency of 34.3%, a peak luminance of 57376 cd m−2, and small efficiency roll‐off.
Novel lactam electron‐acceptors are utilized to construct high‐performance TADF molecules. The rigid molecular skeletons, ordered molecular arrangements, and precise control of excited states contribute to achieving ultra‐high PLQYs (98%−99%), high horizontal dipole ratios (87%−91%), and rapid RISC (kRISC ≈ 1.7 × 106 s−1) simultaneously. The optimized OLEDs attain high EQEs of up to 34.3%, accompanied by ultra‐high luminances and small efficiency roll‐offs.
Simultaneously achieving a high photoluminescence quantum yield (PLQY), ultrashort exciton lifetime, and suppressed concentration quenching in thermally activated delayed fluorescence (TADF) ...materials is desirable yet challenging. Here, a novel acceptor–donor–acceptor type TADF emitter, namely, 2BO‐sQA, wherein two oxygen‐bridged triarylboron (BO) acceptors are arranged with cofacial alignment and positioned nearly orthogonal to the rigid dispirofluorene‐quinolinoacridine (sQA) donor is reported. This molecular design enables the compound to achieve highly efficient (PLQYs up to 99%) and short‐lived (nanosecond‐scale) blue TADF with effectively suppressed concentration quenching in films. Consequently, the doped organic light‐emitting diodes (OLEDs) base on 2BO‐sQA achieve exceptional electroluminescence performance across a broad range of doping concentrations, maintaining maximum external quantum efficiencies (EQEs) at over 30% for doping concentrations ranging from 10 to 70 wt%. Remarkably, the nondoped blue OLED achieves a record‐high maximum EQE of 26.6% with a small efficiency roll‐off of 14.0% at 1000 candelas per square meter. By using 2BO‐sQA as the sensitizer for the multiresonance TADF emitter ν‐DABNA, TADF‐sensitized fluorescence OLEDs achieve high‐efficiency deep‐blue emission. These results demonstrate the feasibility of this molecular design in developing TADF emitters with high efficiency, ultrashort exciton lifetime, and minimal concentration quenching.
A novel acceptor–donor–acceptor type molecular skeleton is designed to realize blue thermally activated delayed fluorescence with ultrahigh emission efficiencies (up to 99%), nanosecond exciton lifetimes, and effectively suppressed concentration quenching in films. The doped and nondoped organic light‐emitting diodes attain high external quantum efficiencies up to 32.0% and 26.6%, respectively.
The objective of this study was to elucidate possible relationship between middle cerebral artery (MCA) bifurcation aneurysms and bifurcation morphology. In the present study, 799 patients with ...three-dimensional angiography were enrolled, including 115 patients with MCA bifurcation aneurysms and 684 subjects without aneurysms. The MCA bifurcation geometry, including angles formed between two M2 segments (φ1) and between M1 and M2 segments, vessel diameters and aneurysm sizes were measured. DA ratio (larger/smaller M2 in diameter) and LA ratio (larger/smaller lateral angle) were also analyzed. The LA and DA ratios and angle φ1 were significantly (P < 0.0001) greater in patients harboring MCA bifurcation aneurysms than in the control, whereas lateral angles and bifurcation branch diameters were significantly smaller (P < 0.01) in patients with than without bifurcation aneurysms. Angle φ1 was significantly increased (P < 0.0001) while both lateral angles significantly decreased (P < 0.0001 and P = 0.0005, respectively) with increase of patients' age. The size of MCA bifurcation aneurysms was significantly (P < 0.05) positively correlated with the bifurcation vascular diameter and aneurysm neck at the MCA bifurcation. A significantly positive correlation existed between aneurysm neck and DA ratio (P = 0.0075), whereas an inverse correlation between aneurysm neck and LA ratio (P = 0.0219). MCA bifurcation aneurysms were mostly deviated toward the smaller lateral angles and smaller M2 branch. In conclusion, aneurysmal MCA bifurcations have asymmetrical bifurcation structures with widened bifurcation angles, narrowed lateral angles, decreased M1 diameter, imbalanced lateral angles and M2 segments, with the cutoff bifurcation angle of 125.0° and cutoff lateral angle ratio of 1.57 for predicting MCA bifurcation aneurysms, whereas normal MCA bifurcations show close to symmetrical structures in the lateral angles and M2 branches.
The aim of this study was to identify the exact origin of force sense and identify whether it arises centrally or peripherally. The present study was designed to analyze the effects of short-term ...fatigue on pinch force sense and the duration of these effects. During the fatigue protocol, twenty (10 men and 10 women; M
= 22.0 years old) young Chinese participants were asked to squeeze maximally until the pinch grip force decreased to 50% of its maximal due to fatigue. Participants were instructed to produce the target force (10% of maximal voluntary isometric contraction) using the same hand before and after fatigue (immediately, 10, 30, 60, 180, 300 s). The results showed significantly higher absolute error immediately after fatigue (1.22 ± 1.06 N) than before fatigue (0.68 ± 0.34 N), and 60 s (0.76 ± 0.69 N), 180 s (0.67 ± 0.42 N), and 300 s (0.75 ± 0.37 N) after fatigue (all P < 0.05) but with no effect on the variable error (P > 0.05). It was also revealed that there was a significant overestimate of the constant error values before (0.32 ± 0.61 N) and immediately after fatigue (0.80 ± 1.38 N, all P < 0.05), while no significant overestimation or underestimation exceeded 300 s after fatigue (P > 0.05). Our study results revealed that short-term fatigue resulted in a significant decrease in force sense accuracy, but it did not affect force sense consistently; however, force sense accuracy recovered to a certain extent within 10 s and 30 s, whereas it recovered fully within 60 s, and force sense directivity improvement exceeded 300 s after fatigue. The present study shows that the sense of tension (peripherally) is also an important factor affecting force sense. Our study supports the view that the periphery is part of the origin of force sense.
The development of orange‐red/red thermally activated delayed fluorescence (TADF) materials with both high emission efficiencies and short lifetimes is highly desirable for electroluminescence (EL) ...applications, but remains a formidable challenge owing to the strict molecular design principles. Herein, two new orange‐red/red TADF emitters, namely AC‐PCNCF3 and TAC‐PCNCF3, composed of pyridine‐3,5‐dicarbonitrile‐derived electron‐acceptor (PCNCF3) and acridine electron‐donors (AC/TAC) are developed. These emitters in doped films exhibit excellent photophysical properties, including high photoluminescence quantum yields of up to 0.91, tiny singlet‐triplet energy gaps of 0.01 eV, and ultrashort TADF lifetimes of less than 1 µs. The TADF‐organic light‐emitting diodes employing the AC‐PCNCF3 as emitter achieve orange‐red and red EL with high external quantum efficiencies of up to 25.0% and nearly 20% at doping concentrations of 5 and 40 wt%, respectively, both accompanied by well‐suppressed efficiency roll‐offs. This work provides an efficient molecular design strategy for developing high‐performance red TADF materials.
In this work, orange‐red/red thermally activated delayed fluorescence materials achieve high photoluminescence quantum yields of up to 91% with ultrashort exciton lifetimes of less than 1 µs, demonstrating a successful balance between high efficiency and fast reverse intersystem crossing. Highly efficient organic light‐emitting diodes are realized with external quantum efficiencies of up to 25.0% and small efficiency roll‐offs.
In order to investigate the role of lateral angle ratio (LA ratio) and daughter artery ratio (DA ratio) for predicting aneurysmal presence in main cerebral arterial bifurcations, three-dimensional ...cerebral angiographic data of major cerebral artery bifurcations were used for measurement of artery diameters and bifurcation angles including 115 middle cerebral arteries (MCAs), 59 basilar arteries (BAs), 35 internal carotid arteries (ICAs) and 115 anterior cerebral arteries (ACAs) with bifurcation aneurysms and control subjects of 1921 bifurcations with no aneurysms. The LA ratio (larger lateral angle/smaller lateral angle) and DA ratio (larger branch diameter/smaller branch diameter) were calculated, and ROC curve analysis of LA and DA ratios between normal and aneurysmal cases was performed. The LA and DA ratios of MCA bifurcations and the LA ratios of BA and ICA bifurcations with aneurysms were all significantly larger than normal bifurcations (P < 0.05), and the DA ratio of ACA bifurcations with aneurysms was significantly smaller than normal cases (P < 0.01). Moreover, the LA ratio or DA ratio between the normal and aneurysm cases in MCA, BA and ACA bifurcations demonstrated significant differences by ROC analysis (P < 0.01) except in the ICA bifurcations. No significant difference was observed (P > 0.05) between ruptured and unruptured aneurysms in MCA, BA, ICA and ACA bifurcations. In summary, normal MCA, BA and ICA bifurcations show symmetrical morphology in the lateral angles and daughter branches, whereas aneurysmal bifurcations show asymmetrical morphology. Normal ACA bifurcations have asymmetrical bilateral daughter branches while symmetrical branches are associated with ACA bifurcation aneurysm presence.
The Central Asian Orogenic Belt, as one of world-class gold economic belts, preserves a number of giant, large black shale-hosted gold deposits, while it is still debated for origin of sulfides and ...gold mainly due to lack of identification for multiple stages of sulfides. The Haoyaoerhudong gold deposit is hosted in a sequence of Mesoproterozoic carbonaceous and pyritic slate, phyllite, and schist that form a tight syncline along the north margin of the North China Craton. Detailed petrography of the host rocks and mineralization have defined five stages of pyrites. The earliest form of pyrite (Py1) occurs as fine-grained dispersed pyrite in black carbonaceous slate and medium- to coarse-grained disseminated pyrite in pyrite-rich layers, contains relative low gold and high arsenic content, indicating a syn-sedimentary or diagenetic in origin. Stage II pyrite (Py2) occurs with garnet and quartz inclusions and Py3 occurs as pyrite veins, contains higher gold and lower As content, and are interpreted to have formed from the dissolution-reprecipitation of Py1 during the peak metamorphism or post-peak metamorphism. Stage IV pyrite (Py4) from the pyrite-quartz veins crosscut the metamorphic garnet, contains the highest gold concentrations and other trace elements, and is considered to have formed post-peak metamorphism. Abundant native gold, electrum, and maldonite occur as inclusions within Py4 and monazite and in fractures that crosscut garnet. While, Py5 with typical remobilized feature is thought to be a product of melting of former pyrites (Py1 to Py4) triggered by the large-scale Hercynian magmatism. The sedimentary/diagenetic Py1 have δ34S values that range from +12.4‰ to +16.2‰. Later generations of sulfides, including Py2 to Py5, and Ccp2 to Ccp3, have δ34S values from +9.5‰ to +12.7‰. Monazite with maldonite inclusions from quartz-pyrite veins yielded an intercept age of 341.3 ± 6.6 Ma, while coarse grained monazite associated biotite along fractures in the reefs yielded an intercept age of 254.6 ± 8.2 Ma.
The paragenetic, textural, chemical, and isotopic data suggest three distinct gold producing episodes at Haoyaoerhudong gold deposit. Gold and arsenic were clearly initially concentrated in organic muds, and enriched along the structures of diagenetic arsenic-rich pyrite. Subsequently, accompanying metamorphism and deformation, gold was liberated from the dissolution of diagenetic pyrites to form the pyrite veins. Finally, accompanying transformation of pyrite into pyrrhotite, gold was released into the metamorphic fluids to become concentrated as native gold, electrum, and maldonite in pyrite-quart veins. Monazite with age of 341 Ma from quartz-pyrite veins suggests that the third major gold mineralizing event in Haoyaoerhudong occurred before the Hercynian magmatism, suggesting that the Haoyaoerhudong deposit is a typical orogenic gold deposit rather than intrusion-related deposit.
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•Distinguishing five stages of pyrite from three stages gold mineralization.•LA-ICP-MS trace element mapping reveals liberation of gold from sedimentary pyrite into hydrothermal fluids.•Monazite data indicates the third gold introduction episode occurred at~341 Ma.•The multistage ore-forming processes and orogenic type were proposed for Haoyaoerhudong deposit.
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