A new class of charge-neutral, bis-tridentate Ir(III) metal complexes is designed, synthesized and applied as emitters in the fabrication of organic light emitting diodes. Their basic properties are ...discussed vs. their tris-bidentate counterparts.
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•Relationship of the terpyridine complexes Ru(tpy)22+ and Ir(tpy)23+ are reviewed.•Dianionic chelates are constructed using pyrazole, pyridine and phenyl fragments.•N^C^N, C^N^C and C^C^C type ancillaries are employed to obtain monoanionic chelates.•Properties of the charge-neutral bis-tridentate Ir(III) complexes are discussed.•Bis-tridentate Ir(III) metal complexes are useful emitters for OLEDs.
This review is an update on current advances in metal complexes with d6-electronic configuration and bearing two tridentate chelates. We first elaborate the basic properties of the famous cationic complexes Ru(tpy)22+ and Ir(tpy)23+, where tpy represents 2,2′:6′,2″-terpyridine. The emphasis is then switched to various charge-neutral, bis-tridentate Ir(III) complexes, with emission spanning the whole visible region from blue, green to red. These Ir(III) metal complexes are capable of exhibiting high luminescence efficiency, reduced radiative lifetime, and adequate volatility and stability, similar to those of their traditional tris-bidentate Ir(III) counterparts, destined to be viable OLED phosphors.
Bacterial infections have caused serious threats to public health due to the antimicrobial resistance in bacteria. Recently, gold nanoclusters (AuNCs) have been extensively investigated for ...biomedical applications because of their superior structural and optical properties. Great efforts have demonstrated that AuNCs conjugated with various surface ligands are promising antimicrobial agents owing to their high biocompatibility, polyvalent effect, easy modification and photothermal stability. In this review, we have highlighted the recent achievements for the utilizations of AuNCs as the antimicrobial agents. We have classified the antimicrobial AuNCs by their surface ligands including small molecules (< 900 Daltons) and macromolecules (> 900 Daltons). Moreover, the antimicrobial activities and mechanisms of AuNCs have been introduced into two main categories of small molecules and macromolecules, respectively. In accordance with the advancements of antimicrobial AuNCs, we further provided conclusions of current challenges and recommendations of future perspectives of antimicrobial AuNCs for fundamental researches and clinical applications.
PtCoFe nanowires with different alloying compositions are chemically prepared and acted as counter electrodes (CEs) in dye‐sensitized solar cells (DSSCs) with Ru(II)‐based dyes. Due to their superior ...I3− reduction activity, PtCoFe nanowires with rich (111) facets enhance the performance of DSSCs. Hence, N719 DSSCs with PtCoFe nanowires, respectively, produce better power conversion efficiency (PCE) of 8.10% for Pt33Co24Fe43 nanowire, 8.33% for Pt74Co12Fe14 nanowire, and 9.26% for Pt49Co23Fe28 nanowire in comparison to the PCE of Pt CE (7.32%). Further, the PRT‐22 DSSC with Pt49Co23Fe28 nanowire exhibits a maximum PCE of 12.29% with a certificated value of 12.0%, which surpass the previous PCE record of the DSSCs with Ru(II)‐based dyes. The photovoltaic and electrochemical results reveal the composition‐dependent activity along with a volcano‐shaped trend in the I−/I3− redox reaction. Theoretical work on the adsorption energies of I2, the desorption energies of I−, and the corresponding absolute energy demonstrates that the I3− reduction activity followed in the order of Pt49Co23Fe28(111) plane > Pt74Co12Fe14(111) plane > Pt33Co24Fe43(111) plane, proving Pt49Co23Fe28 nanowire to be a superior cathode material for DSSCs.
PtCoFe nanowires with rich (111) planes are chemically prepared and act as the counter electrodes of dye‐sensitized solar cells (DSSCs). Evidently, Pt49Co23Fe28 nanowires demonstrate the superior catalytic properties with respect to the I−/I3− redox reactions. Thus, PRT‐22 DSSC based on Pt49Co23Fe28 nanowire produces an impressive power conversion efficiency of 12.29%.
This paper studies the amplitude-frequency characteristic of frontal steady-state visual evoked potential (SSVEP) and its feasibility as a control signal for brain computer interface (BCI). SSVEPs ...induced by different stimulation frequencies, from 13 ~ 31 Hz in 2 Hz steps, were measured in eight young subjects, eight elders and seven ALS patients. Each subject was requested to participate in a calibration study and an application study. The calibration study was designed to find the amplitude-frequency characteristics of SSVEPs recorded from Oz and Fpz positions, while the application study was designed to test the feasibility of using frontal SSVEP to control a two-command SSVEP-based BCI. The SSVEP amplitude was detected by an epoch-average process which enables artifact-contaminated epochs can be removed. The seven ALS patients were severely impaired, and four patients, who were incapable of completing our BCI task, were excluded from calculation of BCI performance. The averaged accuracies, command transfer intervals and information transfer rates in operating frontal SSVEP-based BCI were 96.1%, 3.43 s/command, and 14.42 bits/min in young subjects; 91.8%, 6.22 s/command, and 6.16 bits/min in elders; 81.2%, 12.14 s/command, and 1.51 bits/min in ALS patients, respectively. The frontal SSVEP could be an alternative choice to design SSVEP-based BCI.
Femoral neck fractures in older adult patients are a major concern and often necessitate surgical intervention. This study compared the clinical outcomes of 2 surgical techniques: the femoral neck ...system (FNS) and cannulated compression screws (CCSs).
A total of 40 female patients (mean age 73.50 ± 11.55 years) with femoral neck fractures of Pauwels classification type II and receiving surgical fixation between 2020 and 2022 were enrolled. The patients were categorized into an FNS group (n = 12) or a CCS group (n = 28), and surgical duration, intraoperative blood loss, length of hospital stay, and incidence of postoperative adverse events were analyzed.
No significant intergroup differences in demographic characteristics were discovered. The mean surgical duration for all patients was 52.88 ± 22.19 min, with no significant difference between the groups. However, the FNS group experienced significantly higher intraoperative blood loss (P = 0.002) and longer hospital stay (P = 0.023) than did the CCS group. The incidence of osteonecrosis was higher in the CCS group, whereas the incidence of nonunion or malunion was higher in the FNS group. The surgical method did not appear to be a significant risk factor. The main risk factor for revision surgery was longer duration until the first adverse event (P = 0.015).
The FNS does not appear to provide superior surgical outcomes compared with CCSs in older adult women with Pauwels classification type II femoral neck fractures. A longer duration between surgical fixation and the first adverse event before stabilization of the fracture site may be a risk factor for revision surgery.
Arsenite-induced stress granule (SG) formation can be cleared by the ubiquitin-proteasome system aided by the ATP-dependent unfoldase p97. ZFAND1 participates in this pathway by recruiting p97 to ...trigger SG clearance. ZFAND1 contains two An1-type zinc finger domains (ZF1 and ZF2), followed by a ubiquitin-like domain (UBL); but their structures are not experimentally determined. To shed light on the structural basis of the ZFAND1–p97 interaction, we determined the atomic structures of the individual domains of ZFAND1 by solution-state NMR spectroscopy and X-ray crystallography. We further characterized the interaction between ZFAND1 and p97 by methyl NMR spectroscopy and cryo-EM. 15N spin relaxation dynamics analysis indicated independent domain motions for ZF1, ZF2, and UBL. The crystal structure and NMR structure of UBL showed a conserved β-grasp fold homologous to ubiquitin and other UBLs. Nevertheless, the UBL of ZFAND1 contains an additional N-terminal helix that adopts different conformations in the crystalline and solution states. ZFAND1 uses the C-terminal UBL to bind to p97, evidenced by the pronounced line-broadening of the UBL domain during the p97 titration monitored by methyl NMR spectroscopy. ZFAND1 binding induces pronounced conformational heterogeneity in the N-terminal domain of p97, leading to a partial loss of the cryo-EM density of the N-terminal domain of p97. In conclusion, this work paved the way for a better understanding of the interplay between p97 and ZFAND1 in the context of SG clearance.
Percutaneous vertebroplasty (PVP) is widely used to treat osteoporotic vertebral compression fractures (OVCFs). The influence of timing (early vs. late) of PVP on the development of adjacent ...vertebral fractures (AVF) has rarely been discussed.
This study aimed to compare the incidence of AVF among patients who received early PVP (= 30 days after symptom onset, EPVP) or late PVP (> 30 days after symptom onset, LPVP) in the thoracolumbar region (T10 to L2) after a 1-year follow up.
A retrospective cohort study.
Department of Orthopedic, an affiliated hospital of a medical university.
Patients who had single-level, T-score = -2.5 of lumbar bone mineral density (BMD), primary OVCF in the thoracolumbar region (T10 to L2) and who received PVP between July 2012 and June 2014 were included in the study. They were divided into early PVP and late PVP groups according to the interval between symptom onset and treatment. The risk factors associated with subsequent AVFs were analyzed.
Of the 225 patients reviewed, 124 met the criteria and were followed for a minimum of 1 year. Eleven patients (14.1%) in the EPVP group (n = 78) and 18 patients (39.1%) in the LPVP group (n = 46) experienced an AVF during the first year following vertebroplasty. Outcomes were significantly better in patients with higher bone mineral density, lower cement volume, and without cement leakage (P < 0.01). Cox regression indicated an increase risk for AVF for LPVP, with an adjusted hazard ratio of 6.08 (95% confidence interval: 2.50-14.81).
The incidence of AVFs could be over estimated due to this being a retrospective study with a small case number and lack of either biomechanical study of intra-vertebral cement distribution by times to support the result.
Compared with later interventions, PVP performed within 30 days after fracture development may be associated with a lower risk of adjacent fractures in the thoracolumbar region.
Percutaneous vertebroplasty, osteoporosis, osteoporotic vertebral compression fracture, adjacent vertebral fracture.
Bis-tridentate Ru( ii ) sensitizers with a 4,4′,4′′-tricarboxy-2,2′:6′,2′′-terpyridine anchor ( i.e. tctpy) and a 2,6-dipyrazolyl pyridine ancillary ligand with either 5-dodecylthien-2-yl or t -butyl ...substituents at the central pyridyl unit and four distinctive perfluoroalkyl fragments ( e.g. CF 3 , C 3 F 7 , C 5 F 11 and C 7 F 15 ) at the terminal pyrazolyl sites were designed, synthesized and applied as sensitizers for the fabrication of dye-sensitized solar cells. All these sensitizers exhibited suitable optical properties and electrochemical characteristics. In addition, despite the TF- t Bu series of sensitizers with t -butyl substituents showing a lowered absorption extinction coefficient vs. their 5-dodecylthien-2-yl substituted counterparts ( i.e. TF-2′ series) in solution, their smaller molecular size allowed a larger dye loading on TiO 2 photoanodes, which offsets the inferior optical response and makes them the better DSC sensitizers. After appropriate selection of C 3 F 7 substituents, the sensitizer coded TF- t Bu_C 3 F 7 showed the highest overall efficiencies of J SC = 18.47 mA cm −2 , V OC = 767 mV, FF = 0.71 and PCE = 10.05% under simulated one sun irradiation, due to the fine balance between dye loading and reduced charge recombination. The corresponding enlarged solar cell module with an active area of 11.2 cm 2 also showed the best PCE of 7.55% under one sun irradiation with PCE reaching 12.70% under T5 lighting at 2400 lux.
Lysosomal cell death is induced by lysosomal membrane permeabilization (LMP) and the subsequent release of lysosomal proteolytic enzymes, including cathepsins (CTSs), which results in mitochondrial ...dysfunction and apoptosis. Imiquimod (IMQ), a synthetic TLR7 ligand, has both antiviral and antitumor activity against various skin malignancies in clinical treatment. Previously, we demonstrated IMQ not only caused lysosomal dysfunction but also triggered lysosome biogenesis to achieve lysosomal adaptation in cancer cells.
To determine whether lysosomes are involved in IMQ-induced apoptosis.
The human skin cancer cell lines BCC, A375 and mouse melanoma cell line B16F10 were used in all experiments. Cell death was determined by the Cell Counting Kit-8 (CCK-8) assay and DNA content assay. Protein expression was determined by immunoblotting. Caspase-8 activity was assessed using a fluorescence caspase-8 kit and determined by flow cytometry and confocal microscopy.
IMQ not only induced lysosome damage but also abrogated lysosome function in skin cancer cells. IMQ-induced caspase-8 activation contributed to the processes of lysosomal cell death. Moreover, the use of ROS scavengers significantly abolished caspase-8 activation and inhibited IMQ-induced LMP. Additionally, pharmacological inhibition of CTSD not only abrogated caspase-8 activation but also rescued IMQ-induced cell death. Finally, lysosome-alkalizing agents enhanced the cytotoxicity of IMQ in vitro and in vivo.
IMQ-induced ROS accumulation promotes LMP, releases CTSs into the cytosol, stimulates caspase-8 activation and finally causes lysosomal cell death. Lysosomal cell death and the CTSD/caspase-8 axis may play a crucial role in IMQ-induced cell death.
•IMQ causes lysosomal membrane permeabilization and CTSs releasing into cytosol in skin cancer cells.•IMQ induces lysosomal cell death which is mediated by CTSD/caspase-8 axis.•IMQ-induced ROS generation is crucial for IMQ-induced caspase-8 activation and lysosomal cell death.•Combination treatment with lysosome-alkalinizing agents and IMQ enhances anti-tumor response in skin cancer cells.
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