Rational Design of Nitride Phosphor-In-Glass with Robust Stability and Photoluminescence Performance

Phosphor-in-glass represents a promising avenue for merging the luminous efficiency of high-quality phosphor and the thermal stability of a glass matrix. Undoubtedly, the glass matrix system and its preparation are pivotal factors in achieving high stability and preserving the original performance of embedded phosphor particles. In contrast to the well-established commercial Y3Al5O12:Ce3+ oxide phosphor, red nitride phosphor, which plays a critical role in high-quality lighting, exhibits greater structural instability during the high-temperature synthesis of inorganic glasses. A telluride glass with a refractive index (RI = 2.15@615 nm) akin to that of nitride phosphor (∼2.19) has been devised, demonstrating high efficiency in photon utilization. The lower glass-transition temperature plays a crucial role in safeguarding phosphor particles against erosion resulting from exposure to high-temperature melts. Phosphor-in-glass retains 93% of the quantum efficiency observed for pure phosphor. The assembled white light-emitting diodes module has precise color tuning capabilities, achieving an optimal color rendering index of 93.7, a luminous efficacy of 80.4 lm/W, and a correlated color temperature of 5850 K. These outcomes hold potential for advancing the realm of inorganic package and high-quality white light illumination.

Rational ligand design for enhanced carrier mobility in self-powered SWIR photodiodes based on colloidal InSb quantum dots

Solution-processed colloidal III-V semiconductor quantum dot photodiodes (QPDs) have potential applications in short-wavelength infrared (SWIR) imaging due to their tunable spectral response range, possible multiple-exciton generation, operation at 0-V bias voltage and low-cost fabrication and are also expected to replace lead- and mercury-based counterparts that are hampered by reliance on restricted elements (RoHS). However, the use of III-V CQDs as photoactive layers in SWIR optoelectronic applications is still a challenge because of underdeveloped ligand engineering for improving the in-plane conductivity of the QD assembled films. Here, we report on ligand engineering of InSb CQDs to enhance the optical response performance of self-powered SWIR QPDs. Specifically, by replacing the conventional ligand (i.e., oleylamine) with sulfide, the interparticle distance between the CQDs was shortened from 5.0 ± 0.5 nm to 1.5 ± 0.5 nm, leading to improved carrier mobility for high photoresponse speed to SWIR light. Furthermore, the use of sulfide ligands resulted in a low dark current density (∼nA cm-2) with an improved EQE of 18.5%, suggesting their potential use in toxic-based infrared image sensors.

Comparative Analysis of the Efficacy of Spinal Cord Stimulation and Traditional Debridement Care in the Treatment of Ischemic Diabetic Foot Ulcers: A Retrospective Cohort Study

BACKGROUND AND OBJECTIVES

Spinal cord stimulation (SCS) is an effective treatment for diabetic peripheral neuropathy. The purpose of this study was to investigate the effectiveness of SCS in the treatment of ischemic diabetic foot ulcers.

METHODS

In this retrospective study, the SCS group comprised 102 patients with ischemic diabetic foot who were treated with SCS for foot ulcers and nonhealing wounds due to severe lower limb ischemia. The traditional debridement care (TDC) group comprised 104 patients with ischemic diabetic foot who received only TDC. Strict screening criteria were applied. The assignment of patients to either group depended solely on their willingness to be treated with SCS. Secondary end points were transcutaneous partial pressure of oxygen (PtcO2), ankle-brachial index (ABI), and color Doppler of the lower limb arteries in the feet at 6 months and 12 months after treatment. The primary end point was the amputation.

RESULTS

The dorsal foot PtcO2 and ABI of the patients in the SCS group were significantly improved at 6 months and 12 months postoperation (P < .05). The therapeutic efficacy was significantly better than that of the TDC group over the same period of time (P < .05). The degree of vasodilation of the lower limb arteries (ie, femoral, popliteal, posterior tibial, and dorsalis pedis arteries) on color Doppler was higher in the SCS group than in the TDC group (P < .05). The odds ratios for total amputation at 6 and 12 months postoperatively in the SCS group were 0.45 (95% CI, 0.19-1.08) and 0.17 (95% CI, 0.08-0.37), respectively, compared with the TDC group.

CONCLUSION

SCS improved symptoms of lower limb ischemia in ischemic diabetic feet and reduced the rate of toe amputation by increasing PtcO2, ABI, and arterial vasodilation in the lower limbs.

Highly efficient, self-powered UV photodiodes based on leadfree perovskite nanocrystals through interfacial engineering

Double perovskite crystals are promising alternatives for lead-based perovskites that has potential to address toxicity and instability issues. In this study, Cs2AgBiCl6nanocrystals (NCs) with high absorption coefficients were synthesized by hot-injection method. The bandgap engineering was realized by tuning the halide composition in Cs2AgBiCl6to Cs2AgBiBr6. Both NCs were used as light-absorbing layers in lead-free perovskite photodiodes that exhibit wavelength-selectivity for UV-visible light operatable even at a bias voltage of 0 V. Cs2AgBiBr6-based photodiode exhibits a characteristic detection peak at 340 nm with a responsivity of 3.21 mA W-1, a specific detectivity up to 8.91 × 1010Jones and a fast response speed with a rise/fall time of 30/35 ms. The excellent performance of self-driven photodiodes lights up the prospect of lead-free perovskite NCs in highly efficient optoelectronic devices.

Interpeduncular cistern intrathecal targeted drug delivery for intractable postherpetic neuralgia: A case report

BACKGROUND

Intractable postherpetic neuralgia (PHN) can be difficult to manage even with aggressive multimodal therapies. Patients who experience uncontrolled refractory cranial PHN despite conservative treatment may benefit from an intrathecal drug delivery system (IDDS). For craniofacial neuropathic pain, the traditional approach has been to place the intrathecal catheter tip below the level of the cranial nerve root entry zones, which may lead to insufficient analgesia.

CASE SUMMARY

We describe a 69-year-old man with a 1-year history of PHN after developing a vesicular rash in the ophthalmic division of cranial nerve V (trigeminal nerve) distribution. The pain was rated 7-8 at rest and 9-10 at breakthrough pain (BTP) on a numeric rating scale. Despite receiving aggressive multimodal therapies including large doses of oral analgesics (gabapentin 150 mg q12 h, oxycodone 5 mg/acetaminophen 325 mg q6 h, and lidocaine 5% patch 700 mg q12 h) and sphenopalatine ganglion block, there was no relief of pain. Subsequently, the patient elected to have an implantable IDDS with the catheter tip placed at the interpeduncular cistern. The frequency of BTP episodes decreased. The patient's continuous daily dose was adjusted to 0.032 mg/d after 3 mo of follow-up and stopped 5 mo later. He did not report pain or other discomfort at outpatient follow-up 6 mo and 1 year after stopping intracisternal hydromorphone.

CONCLUSION

The use of interpeduncular cistern intrathecal infusion with low-dose hydromorphone by IDDS may be effective for severe craniofacial PHN.

Fabrication of Super-Sized Metal Inorganic-Organic Hybrid Glass with Supramolecular Network via Crystallization-Suppressing Approach

Metal coordination compound (MCC) glasses [e.g., metal-organic framework (MOF) glass, coordination polymer glass, and metal inorganic-organic complex (MIOC) glass] are emerging members of the hybrid glass family. So far, a limited number of crystalline MCCs can be converted into glasses by melt-quenching. Here, we report a universal wet-chemistry method, by which the super-sized supramolecular MIOC glasses can be synthesized from non-meltable MOFs. Alcohol and acid were used as agents to inhibit crystallization. The MIOC glasses demonstrate unique features including high transparency, shaping capability, and anisotropic network. Directional photoluminescence with a large polarization ratio (≈47 %) was observed from samples doped with organic dyes. This crystallization-suppressing approach enables fabrication of super-sized MCC glasses, which cannot be achieved by conventional vitrification methods, and thus allows for exploring new MCC glasses possessing photonic functionalities.

Impact of coherent core/shell architecture on fast response in InP-based quantum dot photodiodes

Solution-processed, cadmium-free quantum dot (QD) photodiodes are compatible with printable optoelectronics and are regarded as a potential candidate for wavelength-selective optical sensing. However, a slow response time resulting from low carrier mobility and a poor dissociation of charge carriers in the optically active layer has hampered the development of the QD photodiodes with nontoxic device constituents. Herein, we report the first InP-based photodiode with a multilayer device architecture, working in photovoltaic mode in photodiode circuits. The photodiode showed the fastest response speed with rising and falling times of τ _r = 4 ms and τ _f = 9 ms at a voltage bias of 0 V at room temperature in ambient air among the Cd-free photodiodes. The single-digit millisecond photo responses were realized by efficient transportation of the photogenerated carriers in the optically active layer resulting from coherent InP/ZnS core/shell QD structure, fast separation of electron and hole pairs at the interface between QD and Al-doped ZnO layers, and optimized conditions for uniform deposition of each thin film. The results suggested the versatility of coherent core/shell QDs as a photosensitive layer, whose structures allow various semiconductor combinations without lattice mismatch considerations, towards fast response, high on/off ratios, and spectrally tunable optical sensing.

[Validation of calculation method for dose distribution around radioactive iodine-125 particles based on AAPM TG43 report]

Objective: According to the formula provided by the TG43 report [AAPM TG43 (2004)] proposed by the American Association of Physicists in Medicine (AAPM) in 2004, we calculated the dose distribution around the radioactive iodine-125 particles, and verified the calculation accuracy of the radioactive iodine-125 particles treatment planning system. Methods: AAPM TG43 (2004) report provides two calculation methods when calculating the dose around a single radioactive source. The calculation method that does not consider the geometric structure of the radioactive source is called point source calculation method, and the calculation method that considers the geometric structure of the radioactive source is called line source calculation method. Assuming a single Amersham 6711 radioactive iodine-125 particle with an activity of 100 U, the following point doses were calculated according to the two calculation methods provided by AAPM TG43 (2004) report, at 0°, 90° directions, distances 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5 and 6 cm; In the direction of 45°, the doses at 0.71, 1.41, 2.12, 2.83, 3.54, 4.24, 4.95, 5.66, 6.36, 7.07, 7.78 and 8.49 cm. On the clinically used brachytherapy planning system variseeds 8.0, the above two calculation methods are used to calculate the corresponding activity and the dose around the corresponding type of radioactive iodine-125 particles, and the function of capturing points to templates built in the planning system is used to accurately find the above corresponding point position, using a single measurement of the above corresponding point dose; and comparation of the results were performed to see if there is a statistical difference. Results: The AAPM TG43 report uses point source calculation method to calculate the dose of single Amersham 6711 radioactive iodine-125 particles with activity of 100 U at 0° and 90° directions. The points with the same distance and the same dose are 8 082.18, 1 870.08, 756.58, 381.47, 217.11, 131.91, 86.55, 58.32, 39.97, 27.42, 19.74, 14.13 Gy, respectively, at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5 and 6 cm away from them. In the 45° direction, the doses at the distances of 0.71, 1.41, 2.12, 2.83, 3.54, 4.24, 4.95, 5.66, 6.36, 7.07, 7.78 and 8.49 cm are 3 957.37, 865.83, 329.99, 155.69, 84.10, 48.50, 28.49, 17.80, 11.37, 7.38, 4.98 and 3.39 Gy, respectively; For line source calculation method, radioactive particles are at the same distance as above. The doses at each point in the direction of 0° are 3 128.71, 755.44, 330.30, 180.53, 107.74, 68.56, 46.40, 32.22, 22.70, 16.00, 11.51, 8.24 Gy, respectively. The doses at each point in the direction of 90° are 8 306.46, 1 981.01, 802.74, 405.38, 230.60, 140.03, 91.83, 61.84, 42.36, 29.05, 20.91, 14.97 Gy; In the 45° direction, the dose at the corresponding distance as above is 4 020.78, 877.43, 333.49, 156.93, 84.69, 48.81, 28.65, 17.89, 11.42, 7.41, 4.99 and 3.40 Gy, respectively. The maximum dose difference (0.3%) between the two methods is 7.78 cm in the 45° direction, the maximum difference (-0.3%) between the two methods is 8.49 cm in the 45° direction, and the value of other sampling points is less than 0.3%. The closer the Amersham 6711 iodine-125 particles are to the source in the directions of 0°, 45°, and 90°, the faster the dose will drop, and the dose will drop gradually as the distance increases. Conclusion: The brachytherapy planning system variseeds 8.0 and the AAPM TG43 report calculate a maximum dose difference of 0.3%, which can accurately calculate the dose distribution around radioactive iodine-125 seeds, and provide a reliable tool for the clinical implementation of radioactive iodine-125 particles implantation for tumor treatment.

Postproduction Approach to Enhance the External Quantum Efficiency for Red Light-Emitting Diodes Based on Silicon Nanocrystals

Despite bulk crystals of silicon (Si) being indirect bandgap semiconductors, their quantum dots (QDs) exhibit the superior photoluminescence (PL) properties including high quantum yield (PLQY > 50%) and spectral tunability in a broad wavelength range. Nevertheless, their low optical absorbance character inhibits the bright emission from the SiQDs for phosphor-type light emitting diodes (LEDs). In contrast, a strong electroluminescence is potentially given by serving SiQDs as an emissive layer of current-driven LEDs with (Si-QLEDs) because the charged carriers are supplied from electrodes unlike absorption of light. Herein, we report that the external quantum efficiency (EQE) of Si-QLED was enhanced up to 12.2% by postproduction effect which induced by continuously applied voltage at 5 V for 9 h. The active layer consisted of SiQDs with a diameter of 2.0 nm. Observation of the cross-section of the multilayer QLEDs device revealed that the interparticle distance between adjacent SiQDs in the emissive layer is reduced to 0.95 nm from 1.54 nm by “post-electric-annealing”. The shortened distance was effective in promoting charge injection into the emission layer, leading improvement of the EQE.

Input to state stabilization of networked systems under a specified packet dropout rate

This paper studies an input to state stabilizing control of networked control systems (NCSs) under a specified packet dropout rate. By considering packet dropouts in the NCSs, the transmission intervals are categorized by small delay intervals (packet-dropout-free case) and large delay intervals (packet-dropout case). Based on such classifications, we establish the concept of average packet dropout rate (ADR) to characterize the quality of service (QoS) for networks. Then, a switched systems approach is used to derive the ISS (input to state stability) conditions by exploiting Lyapunov theory and input delay approach for a specified ADR. In what follows, the controller design method for the NCSs under a specified ADR is reached by solving linear matrix inequalities (LMIs). According to the proposed results, a control and communication co-design method is developed such that one can design the controller gain according to QoS. Finally, simulations on self-steering control of autonomous vehicles are presented to verify the effectiveness of the proposed co-design method.

Infarct-preconditioning exosomes of umbilical cord mesenchymal stem cells promoted vascular remodeling and neurological recovery after stroke in rats

Background

Stroke is the leading cause of disability worldwide, resulting in severe damage to the central nervous system and disrupting neurological functions. There is no effective therapy for promoting neurological recovery. Growing evidence suggests that the composition of exosomes from different microenvironments may benefit stroke. Therefore, it is reasonable to assume that exosomes secreted in response to infarction microenvironment could have further therapeutic effects.

Methods

In our study, cerebral infarct tissue extracts were used to pretreat umbilical cord mesenchymal stem cells (UCMSC). Infarct-preconditioned exosomes were injected into rats via tail vein after middle cerebral artery occlusion (MCAO). The effect of infarct-preconditioned exosomes on the neurological recovery of rats was examined using Tunel assay, 2,3,5-triphenyltetrazolium chloride (TTC) assay, magnetic resonance imaging (MRI) analyses, modified Neurological Severity Score (mNSS), Morris water maze (MWM), and vascular remodeling analysis. Mi-RNA sequencing and functional enrichment analysis were used to validate the signal pathway involved in the effect of infarct-preconditioned exosomes. Human umbilical vein endothelial cells (HUVECs) were co-cultured with the isolated exosomes. Cell Counting Kit-8 (CCK-8) assay, scratch healing, and Western blot analysis were used to detect the biological behavior of HUVECs.

Results

The results showed that compared with normal exosomes, infarct-preconditioned exosomes further promoted vascular remodeling and recovery of neurological function after stroke. The function of upregulated miRNAs and their target genes which is beneficial to vascular smooth muscle cells verified the importance of vascular remodeling in improving stroke. Better resistance to oxygen–glucose deprivation/reoxygenation (OGD/R), reduced apoptosis, and enhanced migration were observed in infarct-preconditioned exosomes-treated umbilical vein endothelial cells.

Conclusions

Our results demonstrated that infarct-preconditioned exosomes promoted neurological recovery after stroke by enhancing vascular endothelial remodeling, suggested that infarct-preconditioned exosomes could be a novel way to alleviate brain damage following a stroke.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03083-9.

Microvascular decompression for a patient with oculomotor palsy caused by posterior cerebral artery compression: A case report and literature review

BACKGROUND

Aneurysm compression, diabetes, and traumatic brain injury are well-known causative factors of oculomotor nerve palsy (ONP), while cases of ONP induced by neurovascular conflicts have rarely been reported in the medical community. Here, we report a typical case of ONP caused by right posterior cerebral artery (PCA) compression to increase neurosurgeons’ awareness of the disease and reduce misdiagnosis and recurrence.

CASE SUMMARY

A 54-year-old man without a known medical history presented with right ONP for the past 5 years. The patient presented to the hospital with right ptosis, diplopia, anisocoria (rt 5 mm, lt 2.5 mm), loss of duction in all directions, abduction, and light impaired pupillary reflexes. Magnetic resonance angiography and computed tomography venography examinations showed no phlebangioma, aneurysm, or intracranial lesion. After conducting oral glucose tolerance and prostigmin tests, diabetes and myasthenia gravis were excluded. Cranial nerve magnetic resonance imaging showed that the right PCA loop was in direct contact with the cisternal segment of the right oculomotor nerve (ON). Microvascular decompression (MVD) of the culprit vessel from the ON through a right subtemporal craniotomy was carried out, and the ONP symptoms were significantly relieved after 3 mo.

CONCLUSION

Vascular compression of the ON is a rare pathogeny of ONP that may be refractory to drug therapy and ophthalmic strabismus surgery. MVD is an effective treatment for ONP induced by neurovascular compression.

Impact of bismuth-doping on enhanced radiative recombination in lead-free double-perovskite nanocrystals

Lead-free double-perovskite nanocrystals (NCs) have received considerable attention as promising candidates for environmentally friendly optical applications. Furthermore, double-perovskite nanostructures are known to be physically stable compared to most other inorganic halide perovskites, with a generic chemical formula of ABX₃ (e.g., A = Cs⁺; B = Sn²⁺ or Ge²⁺; X = Cl^-, Br^-, I^-, or their combination). However, relevant experimental studies on the photophysical properties are still insufficient for Pb-free double-perovskite NCs. Herein, we synthesized Cs₂Ag_0.65Na_0.35InCl₆ NCs doped with bismuth (Bi³⁺) ions and investigated their photophysical properties to reveal the role of the dopant on the enhanced photoemission properties. Specifically, it was found that the photoluminescence quantum yield (PLQY) increased up to 33.2% by 2% Bi-doping. The optical bandgap of the NCs decreased from 3.47 eV to 3.41 eV as the amount of the dopant increased from 2% to 15%. To find out the effect of Bi-doping, the temperature-dependent PL properties of the undoped and doped NCs were investigated by utilizing steady-state and time-resolved PL spectroscopy. With increasing the temperature from 20 K to 300 K, the PL intensities of the doped NCs decreased slower than the undoped ones. The correlated average PL lifetimes of both the bismuth-doped and undoped NCs decreased with increasing the temperature. The experimental results revealed that all the NC samples showed thermal quenching with the temperature increasing, and the PL quenching was suppressed in bismuth-doped NCs.

Coherent InP/ZnS core@shell quantum dots with narrow-band green emissions

We report, for the first time, that the coherent growth of zinc sulfide (ZnS) on a colloidal indium phosphide (InP) quantum dot (QD) yields a InP/ZnS core/shell structure with a single lattice constant of 0.563 nm. Compared to the bulk crystal of zinc-blend (cubic) InP, the lattice of the core QD is compressed by 4.1%. In contrast, the lattice of the shell expands by 4.1% relative to the bulky ZnS crystal throughout the core/shell QD if the shell is thinner than or equal to 0.81 nm and the diameter of the core QD is smaller than 2.64 nm. Under these conditions, the bandgap of the core QD increases, resulting in a blueshift of absorption and photoluminescence (PL) spectra. The PL peak is centered at 523 nm. Furthermore, the PL quantum yield is enhanced up to 70% and the PL bandwidth narrows to 36 nm based on the strengthened quantum confinement effect. The temperature dependence of the PL properties is investigated to discuss the effect of the core/shell lattice coherency on the improved PL performances.

Water-Soluble Silicon Quantum Dots toward Fluorescence-Guided Photothermal Nanotherapy

We report carboxy-terminated silicon quantum dots (SiQDs) that exhibit high solubility in water due to the high molecular coverage of surface monolayers, bright light emission with high photoluminescence quantum yields (PLQYs), long-term stability in the PL property for monitoring cells, less toxicity to the cells, and a high photothermal response. We prepared water-soluble SiQDs by the thermal hydrosilylation of 10-undecenoic acid on their hydrogen-terminated surfaces, provided by the thermal disproportionation of triethoxysilane hydrolyzed at pH 3 and subsequent hydrofluoric etching. The 10-undecanoic acid-functionalized SiQDs (UA:SiQDs) showed long-term stability in hydrophilic solvents including ethanol and water (pH 7). We assess their interaction with live cells by means of cellular uptake, short-term toxicity, and, for the first time, long-term cytotoxicity. Results show that UA:SiQDs are potential candidates for theranostics, with their good optical properties enabling imaging for more than 18 days and a photothermal response having a 25.1% photothermal conversion efficiency together with the direct evidence of cell death by laser irradiation. UA:SiQDs have low cytotoxicity with full viability of up to 400 μg/mL for the short term and a 50% cell viability value after 14 days of incubation at a 50 μg/mL concentration.

[The application of 99Tcm-DTPA orbital SPECT/CT in staging evaluation of thyroid associated ophthalmopathy]

Objective: To explore the application value of ⁹⁹Tc^m-diethylenetriaminepentaacetic acid (DTPA) orbital single photon emission computed tomography/computed tomography (SPECT/CT) in staging evaluation of thyroid associated ophthalmopathy (TAO). Methods: A case-control study. A total of 40 patients with binocular TAO were recruited from May 2019 to December 2019 in the Second Hospital of Dalian Medical University. According to the clinical activity score (CAS) standard, 40 TAO patients were divided into the active group (15 cases) and the inactive group (25 cases), and 10 healthy volunteers were recruited as the control group. All subjects underwent ⁹⁹Tc^m-DTPA orbital SPECT/CT examination, and each subject's CAS, reading results and maximum standardized uptake value (SUVmax) were recorded. The Kruskal-Walis H test was used for the CAS comparison among the three groups. The analysis of variance was used for the SUVmax comparison among the three groups. The comparison between CAS and SUVmax before and after treatment was performed by paired samples Wilcoxon signed rank test and paired-sample t test, and Spearman correlation analysis was performed between SUVmax and CAS. The Kappa test was used to check the consistency between the reading result and CAS's judgment of TAO activity. The receiver operating characteristic curve was used to analyze the diagnostic value of the reading results and SUVmax for TAO. Results: The age difference among the three groups was not statistically significant, and the gender difference was not statistically significant (all P>0.05). The difference in CAS among the three groups was statistically significant (H=39.894; P<0.01). Patients with active TAO showed abnormal concentration and enhancement of nuclides in the orbital tissue, and the uptake of radionuclides was significantly increased, while patients with inactive TAO had a slight increase, and healthy volunteers had no significant or only mild uptake. The SUVmax of the active group (2.24±0.47) was highest, and that of the inactive group (1.57±0.43) was higher than the healthy control group (0.67±0.22). After pairwise comparison, there were statistical differences between groups (all P<0.05). According to Spearman correlation analysis, the SUVmax of all TAO patients was linearly, positively correlated with their CAS (r=0.753; P<0.05). In assessing the clinical activity of TAO, the reading results were consistent with CAS (Kappa value=0.737; P<0.05). Taking the reading results as the standard, the area under the receiver operating characteristic curve (AUC) of SUVmax was 0.992, and the threshold of SUVmax to distinguish between active and inactive periods was 1.850, with a sensitivity of 86.70% and a specificity of 76.00%. Taking CAS results as the standard, the AUC of SUVmax was 0.853, and the threshold of SUVmax to distinguish between active and inactive periods was 1.850, with a sensitivity of 100.00% and a specificity of 87.50%. Five patients had inconsistent SUVmax and CAS. The CAS was ≥3, but the orbits did not show any inflammatory lesions in two of them; the CAS was<3, but the orbits showed inflammatory lesions in three of them. Thirteen active TAO patients with ⁹⁹Tc^m-DTPA orbital SPECT/CT showing significant accumulation of nuclides were given hormone shock therapy 12 times. After treatment, the CAS 2.00 (2.00) was lower than the pre-treatment 3.00 (1.50) score, and the difference was statistically significant (Z=-3.100, P<0.01). The SUVmax after treatment (1.60±0.20) was lower than the pre-treatment value (2.17±0.34), and the difference was statistically significant (t=10.197, P<0.01). Conclusion: ⁹⁹Tc^m-DTPA orbital SPECT/CT can relatively accurately determine the state of orbital inflammation in patients with TAO, and can be used as a useful supplement to evaluate the clinical activity of TAO, helping to guide clinical treatment. (Chin J Ophthalmol, 2021, 57: 830-836).

Correlation of MKI67 with prognosis, immune infiltration, and T cell exhaustion in hepatocellular carcinoma

BACKGROUND

MKI67 plays a vital role in the tumour microenvironment (TME) and congenital immunity. The present work focuses on exploring the prognosis prediction performance of MKI67 and its associations with T cell activity and immune infiltration within numerous cancers, especially hepatocellular liver carcinoma (LIHC).

METHODS

Oncomine, GEPIA2, and HPA were adopted to analyse MKI67 levels in different types of cancers. The prognostic prediction performance of MKI67 was evaluated through the TCGA portal, GEPIA2, LOGpc, and Kaplan-Meier Plotter databases. The associations of MKI67 with related gene marker sets and immune infiltration were inspected through TISIDB, GEPIA2, and TIMER. We chose MKI67 to analyse biological processes (BPs) and KEGG pathways related to the coexpressed genes. Furthermore, the gene-miRNA interaction network for MKI67 in liver cancer was also examined based on the miRWalk database.

RESULTS

MKI67 expression decreased in many cancers related to the dismal prognostic outcome of LIHC. We found that MKI67 significantly affected the prognosis of LIHC in terms of histology and grade. Increased MKI67 levels were directly proportional to the increased immune infiltration degrees of numerous immune cells and functional T cells, such as exhausted T cells. In addition, several critical genes related to exhausted T cells, including TIM-3, TIGIT, PD-1, LAG3, and CXCL13, were strongly related to MKI67. Further analyses showed that MKI67 was associated with adaptive immunity, cell adhesion molecules (CAMs), and chemokine/immune response signal transduction pathways.

CONCLUSION

MKI67 acts as a prognostic prediction biomarker in several cancers, particularly LIHC. Upregulation of MKI67 elevates the degree of immune infiltration of many immune cell subtypes, including functional T cells, CD4+ T cells, and CD8+ T cells. Furthermore, MKI67 shows a close correlation with T cell exhaustion, which plays a vital role in promoting T cell exhaustion within LIHC. Detection of the MKI67 level contributes to prognosis prediction and MKI67 modulation within exhausted T cells, thus providing a new method to optimize the efficacy of anti-LIHC immunotherapy.

Phosphatidylcholine-mediated regulation of growth kinetics for colloidal synthesis of cesium tin halide nanocrystals

Cesium tin halide (CsSnX₃, where X is halogen) perovskite nanocrystals (NCs) are one of the most representative alternatives to their lead-based cousins. However, a fundamental understanding of how to regulate the growth kinetics of colloidal CsSnX₃ NCs is still lacking and, specifically, the role of surfactants in affecting their growth kinetics remains incompletely understood. Here we report a general approach for colloidal synthesis of CsSnX₃ perovskite NCs through a judicious combination of capping agents. We demonstrate that introducing a small amount of zwitterionic phosphatidylcholine in the reaction is of vital importance for regulating the growth kinetics of CsSnX₃ NCs, which otherwise merely leads to the formation of large-sized powders. Based on a range of experimental characterization, we propose that the formation of intermediate complexes between zwitterionic phosphatidylcholine and the precursors and the steric hindrance effect of branched fatty acid side-chains of phosphatidylcholine can regulate the growth kinetics of CsSnX₃, which enables us to obtain CsSnX₃ NCs with emission quantum yields among the highest values ever reported. Our finding of using zwitterionic capping agents to regulate the growth kinetics may inspire more research on the synthesis of high-quality tin-based perovskite NCs that could speed up their practical applications in optoelectronic devices.

Cloning and expression analyses of a Pyrabactin Resistance 1 (PYR1) gene from Magnolia sieboldii K. Koch

Magnolia sieboldii K. Koch is endemic to China and has high medicinal and ornamental values. However, its seed exhibits morphophysiological dormancy, and the molecular mechanisms of which are not clearly understood. To reveal the regulation mechanism of the ABA signal in seed dormancy, the M. sieboldii ABA receptor Pyrabactin Resistance 1 (PYR1) gene was cloned and analyzed. Analysis of the MsPYR1 sequence analysis showed that the full-length cDNA contained a complete open reading frame of 987 bp and encoded a predicted protein of 204 amino acid residues. The protein had a relative molecular weight of 22.661 kDa and theoretical isoelectric point of 5.01. The transcript levels of MsPYR1 were immediately upregulated at 16 DAI and then decreased at 40 DAI. The highest transcript level of MsPYR1 was found in the dry seeds, indicating that the MsPYR1 gene may play an important role in the regulation of dormancy. The MsPYR1 gene cDNA was successfully expressed in E. coli Rosetta (DE3), and the protein bands were consistent with the prediction. The Anti-MsPYR1antibody could detect the expression of MsPYR1 in M. sieboldii. The results provided a foundation for further study of the function of the MsPYR1 gene.ABBREVIATIONSABA: Abscisic acid; MPD: morphophysiological; PYR1: Pyrabactin Resistance1; PYL: Pyr1-Like; RCAR: Regulatory Components of Aba Receptors; PP2C: protein phosphatases 2C; SnRK2: sucrose non-fermenting1-related protein kinase2; DAI: day after imbibition; NCBI: National Center for Biotechnology Information; BCA: Bicinchoninic acid; CDD: Conserved Domains.

Theory-Guided Synthesis of Highly Luminescent Colloidal Cesium Tin Halide Perovskite Nanocrystals

The synthesis of highly luminescent colloidal CsSnX₃ (X = halogen) perovskite nanocrystals (NCs) remains a long-standing challenge due to the lack of a fundamental understanding of how to rationally suppress the formation of structural defects that significantly influence the radiative carrier recombination processes. Here, we develop a theory-guided, general synthetic concept for highly luminescent CsSnX₃ NCs. Guided by density functional theory calculations and molecular dynamics simulations, we predict that, although there is an opposing trend in the chemical potential-dependent formation energies of various defects, highly luminescent CsSnI₃ NCs with narrow emission could be obtained through decreasing the density of tin vacancies. We then develop a colloidal synthesis strategy that allows for rational fine-tuning of the reactant ratio in a wide range but still leads to the formation of CsSnI₃ NCs. By judiciously adopting a tin-rich reaction condition, we obtain narrow-band-emissive CsSnI₃ NCs with a record emission quantum yield of 18.4%, which is over 50 times larger than those previously reported. Systematic surface-state characterizations reveal that these NCs possess a Cs/I-lean surface and are capped with a low density of organic ligands, making them an excellent candidate for optoelectronic devices without any postsynthesis ligand management. We showcase the generalizability of our concept by further demonstrating the synthesis of highly luminescent CsSnI_2.5Br_0.5 and CsSnI_2.25Br_0.75 NCs. Our findings not only highlight the value of computation in guiding the synthesis of high-quality colloidal perovskite NCs but also could stimulate intense efforts on tin-based perovskite NCs and accelerate their potential applications in a range of high-performance optoelectronic devices.

First-Principles Study of Bi3+-Related Luminescence and Electron and Hole Traps in (Y/Lu/La)PO4

Bismuth ion-doped phosphate crystals have shown rich luminescence phenomena. However, the complexity and variety of Bi³⁺-related transitions bring great challenges to the understanding of the underlying mechanisms, rendering it hard to rationally design new phosphors and optimize their performance. In this work, we perform first-principles calculations based on the generalized gradient approximation of density functional to obtain the excited state equilibrium geometric structures and then calculate the electronic structures for various Bi³⁺-related excited states in phosphates RPO₄:Bi³⁺ (R = Y, Lu, La) by utilizing the hybrid density functional method. The experimentally measured excitation and emission features are well interpreted by our theoretical calculations. Specifically, we reveal that the emission in LaPO₄:Bi³⁺ is of charge transfer nature, whereas the dominant emission in YPO₄:Bi³⁺ or LuPO₄:Bi³⁺ is the characteristic A band emission. Trapped holes above the valence band maximum due to intrinsic defects are deemed to play a role in the charge-transfer emission of LaPO₄. Our calculations show that the excited state of the Bi³⁺ pair in YPO₄ or LuPO₄ is (Bi³⁺-Bi³⁺)*, rather than Bi²⁺-Bi⁴⁺. Such a Bi³⁺ pair contributes to the longer wavelength emission. Furthermore, our calculations on charge transition levels show that Bi³⁺ ions can act as electron and hole traps in RPO₄ (R = Y, Lu, La). Our work indicates that first-principles calculations can be useful in exploring the diverse luminescence processes in Bi³⁺-doped inorganic insulators.

[Corrigendum] Ouabain suppresses the growth and migration abilities of glioma U‑87MG cells through inhibiting the Akt/mTOR signaling pathway and downregulating the expression of HIF‑1α

Subsequently to the publication of the above paper, an interested reader drew to the authors' attention that several pairings of panels in Fig. 5, as shown on p. 5599, were strikingly similar. After having examined their original data, the authors realized that they uploaded some images incorrectly during the process of compiling this figure, and that there were duplicated data panels in this figure. However, the authors were able to consult their original data, and had access to the correct images. The revised version of Fig. 5, showing the correct data for the Akt/Control, p‑Akt/Control, mTOR/0.05 μM Ouabain, HIF‑1α/0.05 μM Ouabain and Akt/0.5 μM Ouabain experiments, is shown opposite. Note that the replacement of the erroneous data does not affect either the results or the conclusions reported in this paper, and all the authors agree to this Corrigendum. The authors are grateful to the Editor of Molecular Medicine Reports for granting them this opportunity to publish a Corrigendum, and apologize to the readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 17: 5595‑5600, 2018; DOI: 10.3892/mmr.2018.8587].

Collagen/heparan sulfate porous scaffolds loaded with neural stem cells improve neurological function in a rat model of traumatic brain injury

One reason for the poor therapeutic effects of stem cell transplantation in traumatic brain injury is that exogenous neural stem cells cannot effectively migrate to the local injury site, resulting in poor adhesion and proliferation of neural stem cells at the injured area. To enhance the targeted delivery of exogenous stem cells to the injury site, cell therapy combined with neural tissue engineering technology is expected to become a new strategy for treating traumatic brain injury. Collagen/heparan sulfate porous scaffolds, prepared using a freeze-drying method, have stable physical and chemical properties. These scaffolds also have good cell biocompatibility because of their high porosity, which is suitable for the proliferation and migration of neural stem cells. In the present study, collagen/heparan sulfate porous scaffolds loaded with neural stem cells were used to treat a rat model of traumatic brain injury, which was established using the controlled cortical impact method. At 2 months after the implantation of collagen/heparan sulfate porous scaffolds loaded with neural stem cells, there was significantly improved regeneration of neurons, nerve fibers, synapses, and myelin sheaths in the injured brain tissue. Furthermore, brain edema and cell apoptosis were significantly reduced, and rat motor and cognitive functions were markedly recovered. These findings suggest that the novel collagen/heparan sulfate porous scaffold loaded with neural stem cells can improve neurological function in a rat model of traumatic brain injury. This study was approved by the Institutional Ethics Committee of Characteristic Medical Center of Chinese People’s Armed Police Force, China (approval No. 2017-0007.2) on February 10, 2019.

Collagen/heparin scaffold combined with vascular endothelial growth factor promotes the repair of neurological function in rats with traumatic brain injury

The objective of this study was to evaluate the therapy effects of a novel biological scaffold containing heparin, collagen and vascular endothelial growth factor (VEGF) in treating traumatic brain injury (TBI).

VEGF-PLGA controlled-release microspheres enhanced angiogenesis in encephalomyosynangiosis-based chronic cerebral hypoperfusion

Treatments enhancing angiogenesis for chronic cerebral hypoperfusion (CCH) are still in the research stage. Although encephalomyosynangiosis (EMS) is a common indirect anastomosis for the treatment of CCH, the effectiveness to promote angiogenesis is not satisfactory. Vascular endothelial growth factors (VEGF) is a cytokine found to specifically act directly on vascular endothelial cells, promote neovascularization, and enhance capillary permeability. However, the short half life and unstable property of VEGF underlies the need to explore available delivery system. In this study, poly (lactide-co-glycolide) (PLGA) was used to prepare VEGF controlled-release microspheres. In vitro and in vivo analysis of release kinetics showed that the microspheres could release VEGF continuously within 30 days. Then, modified chronic cerebral hypoperfusion rat model was established by ligation of bilateral internal carotid artery and one vertebral artery. At 14 days after ischemia, the EMS and the VEGF microspheres injection were performed. At 30 days after the injection, the result of Morris water maze displayed that combinating VEGF microspheres and EMS significantly ameliorated cognitive deficit after ischemia. We observed that combinating VEGF microspheres and EMS could further significantly increase cerebral blood flow. We speculated that this enhancement of cerebral blood flow was attributed to more angiogenesis induced by combination of VEGF microspheres and EMS, which verified by more collateral circulation with cerebral angiography and higher expression of CD31 or α-SMA. Our study demonstrated that combinating VEGF-PLGA controlled-release microspheres could significantly promote angiogenesis in EMS-based CCH rats model, providing new ideas for clinical treatment of CCH.

Rutaecarpine Ameliorated High Sucrose-Induced Alzheimer's Disease Like Pathological and Cognitive Impairments in Mice

High sucrose can induce tau hyperphosphorylation and cognitive dysfunction/memory impairment as observed in Alzheimer's disease (AD). Rutaecarpine, a specific (transient receptor potential vanilloid 1 [TRPV1]) agonist, is neuroprotective against high sucrose diet-induced impairment, but detailed mechanisms are still elusive. In this study, we investigated whether rutaecarpine mitigates high sucrose diet-induced pathological alterations and cognitive in AD-like mice. Mice were administered fodder containing 0.01% rutaecarpine and 20% sucrose solution. Our results showed that rutaecarpine significantly attenuated high sucrose diet-induced spatial memory impairment and enhanced synaptic plasticity; rutaecarpine prevented high sucrose diet-induced tau hyperphosphorylation by decreasing glycogen synthase kinase-3β (GSK-3β) activity; activation of GSK-3β reversed the protective effect of rutaecarpine on learning and memory deficits, synaptic plasticity, and tau hyperphosphorylation induced by high-glucose diet significantly, suggesting that GSK-3β activation is required for high glucose-induced tau hyperphosphorylation. These results demonstrated that rutaecarpine can mitigate high sucrose diet-induced hyperphosphorylation of AD-associated tau protein and cognitive impairment by inhibiting GSK-3β, which supported that dietary rutaecarpine might have a promising use for therapeutic intervention of AD.

Antithermal Quenching of Luminescence in Zero-Dimensional Hybrid Metal Halide Solids

Zero-dimensional (0D) hybrid metal halides have emerged as a new generation of luminescent phosphors owing to their high radiative recombination rates, which, akin to their three-dimensional cousins, commonly demonstrate thermal quenching of luminescence. Here, we report on the finding of antithermal quenching of luminescence in 0D hybrid metal halides. Using (C₉NH₂₀)₂SnBr₄ single crystals as an example system, we show that 0D metal halides can demonstrate antithermal quenching of luminescence. A combination of experimental characterizations and first-principles calculations suggests that antithermal quenching of luminescence is associated with trap states introduced by structural defects in (C₉NH₂₀)₂SnBr₄. Importantly, we find that antithermal quenching of luminescence is not only limited to (C₉NH₂₀)₂SnBr₄ but also exists in other 0D metal halides. Our work highlights the important role of defects in impacting photophysical properties of hybrid metal halides and may stimulate new efforts to explore metal halides exhibiting antithermal quenching of luminescence at higher temperatures.

TBHQ improved neurological recovery after traumatic brain injury by inhibiting the overactivation of astrocytes

Traumatic brain injury (TBI) is a major leading cause of death and long-term disability. Although astrocytes play a key role in neuroprotection after TBI in the early stage, the overactivation of astrocytes can lead to long-term functional deficits, and the underlying pathophysiological mechanisms remain unclear. In addition, it is unknown whether the nuclear factor erythroid 2-related factor2/haem oxygenase-1 (Nrf-2/HO-1) pathway could elicit a neuroprotective effect by decreasing astrocyte overactivation after TBI. We aimed to study the effects of tert-butylhydroquinone (TBHQ) in reducing astrocyte overactivation after TBI and explored the underlying mechanisms. We first established a controlled cortical impact (CCI) model in rats and performed Haematoxylin and eosin (H&E) staining to observe brain tissue damage. The cognitive function of rats was assessed by modified neurological severity scoring (mNSS) and Morris water maze (MWM) test. Astrocyte and microglia activation was detected by immunofluorescence staining. Oxidative stress conditions were investigated using Western blotting. An enzyme-linked immunosorbent assay (ELISA) was designed to assess the level of the proinflammatory factor tumour necrosis factor-alpha (TNF-α). Dihydroethidium (DHE) staining was used to detect reactive oxygen species (ROS). Apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The results showed that the administration of TBHQ ameliorated motor function and cognitive deficits and decreased the lesion volume. In addition, TBHQ significantly decreased astrocyte overactivation, diminished the pro-inflammatory phenotype M1 and inflammatory cytokines production after TBI, increased Nrf-2 nuclear accumulation, and enhanced the levels of the Nrf-2 downstream antioxidative genes HO-1 and NADPH-quinone oxidoreductase-1 (NQO-1). Furthermore, TBHQ treatment alleviated apoptosis and neuronal death in the cerebral cortex. Overall, our data indicated that the upregulation of Nrf-2 expression could enhance neuroprotection and decrease astrocyte overactivation and might represent a new theoretical basis for treating TBI.

[3D printing non-coplanar template-assisted 125-iodine seed implantation for thorax movement tumor: individual template design method]

Objective: To compare the dosimetric data between preoperative plans and postoperative verification in computed tomography CT-guided and 3D printing template-assisted 125-iodine ((125)I) seed implantation for thorax movement tumor and to explore the feasibility and accuracy of the individualized template design method. Methods: A total of 35 patients, 20 males and 15 females with median age of 62 (17-87) years old, who registered from January 2016 to December 2017 applied with 3D printing guided template assisted radioactive seed implantations in Peking University Third Hospital were included in this study. (125)I seeds with a prescribed dose of 110-180 Gy were impanted. 3D printing templates were designed and produced for 35 cases. The dosimetric parameters: D(90), minimum peripheral dose (mPD), V(100), V(150), V(200), conformal index (CI), external index (EI), and homogeneity index (HI) were compared between pre-and post-plannings. Statistical method was two group of related non-parameters test. Results: The design and production of 35 cases' templates were in place well. Compared with the preoperative planning, the postoperative D(90), V(100), V(150), V(200), mPD, CI, EI and HI differences were 5.57%, 0.34%, 0.33%, -1.20%, 21%, 2.8%, -14.2%, 4.71%, -10.4%. All the included dosimetry parameters changed slightly after surgery compared with before surgery, but the difference was not statistically significant(all P>0.05). Conclusions: The dosimetric parameters of postoperative verification are consistent well with the preoperative planning and have good accuracy, the results could meet the clinical requirements.

Collagen scaffold combined with human umbilical cord-mesenchymal stem cells transplantation for acute complete spinal cord injury

Currently, there is no effective strategy to promote functional recovery after a spinal cord injury. Collagen scaffolds can not only provide support and guidance for axonal regeneration, but can also serve as a bridge for nerve regeneration at the injury site. They can additionally be used as carriers to retain mesenchymal stem cells at the injury site to enhance their effectiveness. Hence, we hypothesized that transplanting human umbilical cord-mesenchymal stem cells on collagen scaffolds would enhance healing following acute complete spinal cord injury. Here, we test this hypothesis through animal studies and a phase I clinical trial. (1) Animal experiments: Models of completely transected spinal cord injury were established in rats and canines by microsurgery. Mesenchymal stem cells derived from neonatal umbilical cord tissue were adsorbed onto collagen scaffolds and surgically implanted at the injury site in rats and canines; the animals were observed after 1 week–6 months. The transplantation resulted in increased motor scores, enhanced amplitude and shortened latency of the motor evoked potential, and reduced injury area as measured by magnetic resonance imaging. (2) Phase I clinical trial: Forty patients with acute complete cervical injuries were enrolled at the Characteristic Medical Center of Chinese People’s Armed Police Force and divided into two groups. The treatment group (n = 20) received collagen scaffolds loaded with mesenchymal stem cells derived from neonatal umbilical cord tissues; the control group (n = 20) did not receive the stem-cell loaded collagen implant. All patients were followed for 12 months. In the treatment group, the American Spinal Injury Association scores and activities of daily life scores were increased, bowel and urinary functions were recovered, and residual urine volume was reduced compared with the pre-treatment baseline. Furthermore, magnetic resonance imaging showed that new nerve fiber connections were formed, and diffusion tensor imaging showed that electrophysiological activity was recovered after the treatment. No serious complication was observed during follow-up. In contrast, the neurological functions of the patients in the control group were not improved over the follow-up period. The above data preliminarily demonstrate that the transplantation of human umbilical cord-mesenchymal stem cells on a collagen scaffold can promote the recovery of neurological function after acute spinal cord injury. In the future, these results need to be confirmed in a multicenter, randomized controlled clinical trial with a larger sample size. The clinical trial was approved by the Ethics Committee of the Characteristic Medical Center of Chinese People’s Armed Police Force on February 3, 2016 (approval No. PJHEC-2016-A8). All animal experiments were approved by the Ethics Committee of the Characteristic Medical Center of Chinese People’s Armed Police Force on May 20, 2015 (approval No. PJHEC-2015-D5).

AT-533, a novel Hsp90 inhibitor, inhibits breast cancer growth and HIF-1α/VEGF/VEGFR-2-mediated angiogenesis in vitro and in vivo

The inhibition of angiogenesis is suggested to be an attractive strategy for cancer therapeutics. Heat shock protein 90 (Hsp90) is closely related to tumorigenesis as it regulates the stabilization and activated states of many client proteins that are essential for cell survival and tumor growth. Here, we investigated the mechanism whereby AT-533, a novel Hsp90 inhibitor, inhibits breast cancer growth and tumor angiogenesis. Based on our results, AT-533 suppressed the tube formation, cell migration, and invasion of human umbilical vein endothelial cells (HUVECs), and was more effective than the Hsp90 inhibitor, 17-AAG. Furthermore, AT-533 inhibited angiogenesis in the aortic ring, Matrigel plug, and chorioallantoic membrane (CAM) models. Mechanically, AT-533 inhibited the activation of VEGFR-2 and the downstream pathways, including Akt/mTOR/p70S6K, Erk1/2 and FAK, in HUVECs, and the viability of breast cancer cells and the HIF-1α/VEGF signaling pathway under hypoxia. In vivo, AT-533 also inhibited tumor growth and angiogenesis by inducing apoptosis and the HIF-1α/VEGF signaling pathway in breast cancer cells. Taken together, our findings indicate that the Hsp90 inhibitor, AT-533, suppresses breast cancer growth and angiogenesis by blocking the HIF-1α/VEGF/VEGFR-2 signaling pathway. AT-533 may thus be a potentially useful drug candidate for breast cancer therapy.

Efficacy of NEMO-binding domain peptide used to treat experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus: an in-vivo study

Purpose

Treatment of chronic osteomyelitis (bone infection) remains a clinical challenge. Our previous study had demonstrated that NEMO-binding domain (NBD) peptide effectively ameliorates the inhibition of osteoblast differentiation by TNF-α in vitro. In this work, NBD peptide was evaluated in vivo for treating chronic osteomyelitis induced by methicillin-resistant Staphylococcus aureus (MRSA) in a rabbit model.

Methods

Tibial osteomyelitis was induced in 50 New Zealand white rabbits by tibial canal inoculation of MRSA strain. After 3 weeks, 45 rabbits with osteomyelitis were randomly divided into four groups that correspondingly received the following interventions: 1) Control group (9 rabbits, no treatment); 2) Van group (12 rabbits, debridement and parenteral treatment with vancomycin); 3) NBD + Van group (12 rabbits, debridement and local NBD peptide injection, plus parenteral treatment with vancomycin); 4) NBD group (12 rabbits, debridement and local NBD peptide injection). Blood samples were collected weekly for the measurement of leucocyte count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels. The rabbits in all four groups were sacrificed 6 weeks after debridement; the anti-infective efficacy was evaluated by radiological, histological, and microbiological examination, and promotion of bone remodeling was quantified by micro-CT using the newly formed bone.

Results

Except two rabbits in the Control group and one in the NBD group that died from severe infection before the end point, the remaining 42 animals (7, 12, 12, 11 in the Control, Van, NBD + Van, and NBD group respectively) were sacrificed 6 weeks after debridement. In general, there was no significant difference in the leucocyte count, and ESR and CRP levels, although there were fluctuations throughout the follow-up period after debridement. MRSA was still detectable in bone tissue samples of all animals. Interestingly, treatment with NBD peptide plus vancomycin significantly reduced radiological and histological severity scores compared to that in other groups. The best therapeutic efficacy in bone defect repair was observed in the NBD peptide + Van group.

Conclusions

In a model of osteomyelitis induced by MRSA, despite the failure in demonstrating antibacterial effectiveness of NBD peptide in vivo, the results suggest antibiotics in conjunction with NBD peptide to possibly have promising therapeutic potential in osteomyelitis.

Halogen Vacancies Enable Ligand-Assisted Self-Assembly of Perovskite Quantum Dots into Nanowires

Interest has been growing in defects of halide perovskites in view of their intimate connection with key material optoelectronic properties. In perovskite quantum dots (PQDs), the influence of defects is even more apparent than in their bulk counterparts. By combining experiment and theory, we report herein a halide-vacancy-driven, ligand-directed self-assembly process of CsPbBr₃ PQDs. With the assistance of oleic acid and didodecyldimethylammonium sulfide, surface-Br-vacancy-rich CsPbBr₃ PQDs self-assemble into nanowires (NWs) that are 20-60 nm in width and several millimeters in length. The NWs exhibit a sharp photoluminescence profile (≈18 nm full-width at-half-maximum) that peaks at 525 nm. Our findings provide insight into the defect-correlated dynamics of PQDs and defect-assisted fabrication of perovskite materials and devices.

Defective [Bi2 O2 ]2+ Layers Exhibiting Ultrabroad Near-Infrared Luminescence

Aurivillius phases have been routinely known as excellent ferroelectrics and have rarely been deemed as materials that luminesce in the near-infrared (NIR) region. Herein, it is shown that the Aurivillius phases can demonstrate broadband NIR luminescence that covers telecommunication and biological optical windows. Experimental characterization of the model system Bi_2.14 Sr_0.75 Ta₂ O_9-x , combined with theoretical calculations, help to establish that the NIR luminescence originates from defective [Bi₂ O₂ ]²⁺ layers. Importantly, the generality of this finding is validated based on observations of a rich bank of NIR luminescence characteristics in other Aurivillius phases. This work highlights that incorporating defects into infinitely repeating [Bi₂ O₂ ]²⁺ layers can be used as a powerful tool to space-selectively impart unusual luminescence emitters to Aurivillius-phase ferroelectrics, which not only offers an optical probe for the examination of defect states in ferroelectrics, but also provides possibilities for coupling of the ferroelectric property with NIR luminescence.

Reducing Defects in Halide Perovskite Nanocrystals for Light-Emitting Applications

The large specific surface area of perovskite nanocrystals (NCs) increases the likelihood of surface defects compared to that of bulk single crystals and polycrystalline thin films. It is thus crucial to comprehend and control their defect population in order to exploit the potential of perovskite NCs. This Perspective describes and classifies recent advances in understanding defect chemistry and avenues toward defect density reduction in perovskite NCs, and it does so in the context of the promise perceived in light-emitting devices. Several pathways for decreasing the defect density are explored, including advanced NC syntheses, new surface-capping strategies, doping with metal ions and rare earths, engineering elemental compensation, and the translation of core-shell heterostructures into the perovskite materials family. We close with challenges that remain in perovskite NC defect research.

3D printing collagen/chitosan scaffold ameliorated axon regeneration and neurological recovery after spinal cord injury

Spinal cord injury (SCI) is a disaster that can cause severe motor, sensory, and functional disorders. Implanting biomaterials have been regarded as hopeful strategies to restore neurological function. However, no optimized scaffold has been available. In this study, a novel 3D printing technology was used to fabricate the scaffold with designed structure. The composite biomaterials of collagen and chitosan were also adopted to balance both compatibility and strength. Female Sprague-Dawley rats were subjected to a T8 complete-transection SCI model. Scaffolds of C/C (collagen/chitosan scaffold with freeze-drying technology) or 3D-C/C (collagen/chitosan scaffold with 3D printing technology) were implanted into the lesion. Compared with SCI or C/C group, 3D-C/C implants significantly promoted locomotor function with the elevation in Basso-Beattie-Bresnahan (BBB) score and angle of inclined plane. Decreased latency and increased amplitude were observed both in motor-evoked potential and somatosensory-evoked potential in 3D-C/C group compared with SCI or C/C group, which further demonstrated the improvement of neurological recovery. Fiber tracking of diffusion tensor imaging (DTI) showed the most fibers traversing the lesion in 3D-C/C group. Meanwhile, we observed that the correlations between the locomotor (BBB score or angle of inclined plane) and the DTI parameters (fractional anisotropy values) were positive. Although C/C implants markedly enhanced biotin dextran amine (BDA)-positive neural profiles compared with SCI group, rats implanted with 3D-C/C scaffold displayed the largest degree of BDA profiles regeneration. Collectively, our 3D-C/C scaffolds demonstrated significant therapeutic effects on rat complete-transected spinal cord model, which provides a promising and innovative therapeutic approach for SCI. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1898-1908, 2019.

[Comparison of preoperative planning of radioactive seed implantation for pelvic wall recurrent gynecological malignant tumors between 3D-printing non-coplanar template and 3D-printing coplanar template]

Objective: To compare the difference of preoperative planning parameters between 3D-printing non-coplanar template (3D-PNCT) and 3D-printing coplanar template (3D-PCT) in the treatment of pelvic wall recurrent gynecological malignant tumor with radioactive seeds implantation, and to guide the clinical application. Methods: From January 2016 to March 2018, 33 patients with pelvic wall recurrent gynecological malignant tumor were treated with radioactive seeds implantation assisted by 3D-printing template and in Peking University Third Hospital. All patients underwent 3D-PNCT and 3D-PCT preoperative planning. The D(90) of target remained similar for the same patient. The parameters were compared with Wilcoxon test or Kruskal-Wallis test. Results: D(90) was similar between the two groups (P>0.05). The number of inserting needles through intestine and bone in 3D-PNCT group was less than that in 3D-PCT group (0 (0-13), 0 (0-25), Z=-2.941, P<0.05;0 (0-3), 0 (0-25), Z=-2.232, P<0.05). Conclusion: For patients with gynecological malignancies with pelvic recurrence, both of the two peroperative plans could achieve prescription dose, but 3D-PNCT is more safer.

ELP2 negatively regulates osteoblastic differentiation impaired by tumor necrosis factor α in MC3T3-E1 cells through STAT3 activation

Tumor necrosis factor‐α (TNF‐α) is a pluripotent signaling molecule. The biological effect of TNF‐α includes slowing down osteogenic differentiation, which can lead to bone dysplasia in long‐term inflammatory microenvironments. Signal transducer and activator of transcription 3 (STAT3)‐interacting protein 1 (StIP1, also known as elongator complex protein 2, ELP2) play a role in inhibiting TNF‐α‐induced osteoblast differentiation. In the present study, we investigated whether and how ELP2 activation mediates the effects of TNF‐α on osteoblastic differentiation. Using in vitro cell cultures of preosteoblastic MC3T3‐E1 cells, we found that TNF‐α inhibited osteoblastic differentiation accompanied by an increase in ELP2 expression and STAT3 activation. Forced ELP2 expression inhibited osteogenic differentiation of MC3T3‐E1 cells, with a decrease in the expression of osteoblast marker genes, alkaline phosphatase activity, and matrix mineralization capacity. In contrast, ELP2 silencing ameliorated osteogenic differentiation in MC3T3‐E1 cells, even after TNF‐α stimulation. The TNF‐α‐induced inhibitory effect on osteoblastic differentiation was therefore mediated by ELP2, which was associated with Janus kinase 2 (JAK2)/STAT3 activation. These results suggest that ELP2 is upregulated at the differentiation of MC3T3‐E1 cells into osteoblasts and inhibits osteogenic differentiation in response to TNF‐α through STAT3 activation.

Discovery of novel elongator protein 2 inhibitors by compound library screening using surface plasmon resonance

Tumour necrosis factor-α (TNF-α) is a pleiotropic cytokine that becomes elevated in chronic inflammatory states, including slowing down osteogenic differentiation, which leads to bone dysplasia in long-term inflammatory microenvironments. The elongator complex plays a role in gene regulation and association with various cellular activities, including the downstream signal transduction of TNF-α in osteogenic cells. To find an inhibitor of Elongator Protein 2 (Elp2), we performed a compound library screen and verified the pharmaceutical effects of candidate compounds on the mouse myoblast cell (C2C12) and mouse osteoblastic cells (MC3T3-E1). The commercial FDA-approved drug (FD) library and the bioactive compound (BC) library were used as candidate libraries. After a label-free, high-throughput affinity measurement with surface plasmon resonance (SPRi), seven kinds of compounds showed binding affinity with mouse Elp2 protein. The seven candidates were then used to perform an inhibition test with TNF-α-induced C2C12 and MC3T3-E1 cell lines. One candidate compound reduced the differentiation suppression caused by TNF-α with resuscitated alkaline phosphatase (ALP) activity, mineralization intensity and expression of osteogenic differentiation marker genes. The results of our study provide a competitive candidate to mitigate the TNF-α-induced osteogenic differentia.