Quantitative Analysis and Comparison Study of [18F]AlF-NOTA-PRGD2, [18F]FPPRGD2 and [68Ga]Ga-NOTA-PRGD2 Using a Reference Tissue Model

With favorable pharmacokinetics and binding affinity for αvβ3 integrin, 18F-labeled dimeric cyclic RGD peptide ([18F]FPPRGD2) has been intensively used as a PET imaging probe for lesion detection and therapy response monitoring. A recently introduced kit formulation method, which uses an 18F-fluoride-aluminum complex labeled RGD tracer ([18F]AlF-NOTA-PRGD2), provides a strategy for simplifying the labeling procedure to facilitate clinical translation. Meanwhile, an easy-to-prepare 68Ga-labeled NOTA-PRGD2 has also been reported to have promising properties for imaging integrin αvβ3. The purpose of this study is to quantitatively compare the pharmacokinetic parameters of [18F]FPPRGD2, [18F]AlF-NOTA-PRGD2, and [68Ga]Ga-NOTA-PRGD2. U87MG tumor-bearing mice underwent 60-min dynamic PET scans following the injection of three tracers. Kinetic parameters were calculated using Logan graphical analysis with reference tissue. Parametric maps were generated using voxel-level modeling. All three compounds showed high binding potential (BpND = k3/k4) in tumor voxels. [18F]AlF-NOTA-PRGD2 showed comparable BpND value (3.75±0.65) with those of [18F]FPPRGD2 (3.39±0.84) and [68Ga]Ga-NOTA-PRGD2 (3.09±0.21) (p>0.05). Little difference was found in volume of distribution (VT) among these three RGD tracers in tumor, liver and muscle. Parametric maps showed similar kinetic parameters for all three tracers. We also demonstrated that the impact of non-specific binding could be eliminated in the kinetic analysis. Consequently, kinetic parameter estimation showed more comparable results among groups than static image analysis. In conclusion, [18F]AlF-NOTA-PRGD2 and [68Ga]Ga-NOTA-PRGD2 have comparable pharmacokinetics and quantitative parameters compared to those of [18F]FPPRGD2. Despite the apparent difference in tumor uptake (%ID/g determined from static images) and clearance pattern, the actual specific binding component extrapolated from kinetic modeling appears to be comparable for all three dimeric RGD tracers

Well-aligned Nickel Nanochains Synthesized by a Template-free Route

Highly uniform and well-aligned one-dimensional Ni nanochains with controllable diameters, including 33, 78, and 120 nm, have been synthesized by applying an external magnetic field without any surface modifying agent. The formation can be explained by the interactions of magnetic dipoles in the presence of applied magnetic field. Magnetic measurements demonstrate that the shape anisotropy dominates the magnetic anisotropy. The demagnetization factor, ∆N, is in the range of 0.23–0.36

Therapeutic Effects of Liposome-Enveloped Ligusticum chuanxiong Essential Oil on Hypertrophic Scars in the Rabbit Ear Model

Hypertrophic scarring, a common proliferative disorder of dermal fibroblasts, results from an overproduction of fibroblasts and excessive deposition of collagen. Although treatment with surgical excision or steroid hormones can modify the symptoms, numerous treatment-related complications have been described. In view of this, we investigated the therapeutic effects of essential oil (EO) from rhizomes of Ligusticum chuanxiong Hort. (Umbelliferae) on formed hypertrophic scars in a rabbit ear model. EO was prepared as a liposomal formulation (liposome-enveloped essential oil, LEO) and a rabbit ear model with hypertrophic scars was established. LEO (2.5, 5, and 10%) was applied once daily to the scars for 28 days. On postoperative day 56, the scar tissue was excised for masson's trichrome staining, detection of fibroblast apoptosis, assays of the levels of collagens I and III, and analysis of the mRNA expression of matrix metalloproteinase-1 (MMP-1), caspase-3 and -9, and transforming growth factor beta 1 (TGF-β1). In addition, the scar elevation index (SEI) was also determined. As a result, LEO treatment significantly alleviated formed hypertrophic scars on rabbit ears. The levels of TGF-β1, MMP-1, collagen I, and collagen III were evidently decreased, and caspase -3 and -9 levels and apoptosis cells were markedly increased in the scar tissue. SEI was also significantly reduced. Histological findings exhibited significant amelioration of the collagen tissue. These results suggest that LEO possesses the favorable therapeutic effects on formed hypertrophic scars in the rabbit ear model and may be an effective cure for human hypertrophic scars

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Cu-assisted austenite reversion and enhanced TRIP effect in maraging stainless steels

202208 bchyNot applicableOthersNational Natural Science Foundation of China; State Key Laboratory for Advanced Metals and Materials Open Fund; Chinese National Engineering Research Centre for Steel Construction (Hong Kong Branch) at PolyU; Guangzhou International Science & Technology Cooperation Program; Youth Innovation Promotion Association of Chinese Academy of Sciences; Innovation Project of Institute of Metal ResearchPublished24 month

Synergistic alloying effects on nanoscale precipitation and mechanical properties of ultrahigh-strength steels strengthened by Ni3Ti, Mo-enriched, and Cr-rich co-precipitates

202106 bcwhNot applicableOthersP0013862, P0020370Published24 month

High-Performance Forward Osmosis Membranes Used for Treating High-Salinity Oil-Bearing Wastewater

Forward osmosis (FO), which is an emerging osmotic driving membrane separation process, can be directly used in high-salinity oil-bearing (HSOB) wastewater treatment. In this study, the thin film composite (TFC) polyamide FO membranes were fabricated for HSOB wastewater treatment. The impacts of the draw solution (DS) concentration, cross-flow rate, stirring rate, and membrane orientation on membrane performances were researched. The results indicated that the FO operation mode was better to achieve a stable water flux of TFC membranes as 29 L/(m(2) h) under a cross-flow rate of 15 cm/s and 3 M NaCl as the DS, which was 61% higher than the water flux in the unoptimized operating conditions (18 L/(m(2) h)). The rejection rate of salt and oil was 99% and 96%. In addition, the effect of different oil concentrations of HSOB wastewater was studied, and the results showed that FO performed well to treat HSOB wastewater when the oil concentration was <700 mg/L

A damage constitutive model for the nonlinear mechanical behavior of C/SiC composites during mechanical cyclical loading/unloading

In this study, the nonlinear mechanical behavior and corresponding damage mechanisms of C/SiC composites during cyclic loading/unloading tensile tests were studied. Besides, based on the composite microstructure and damage mechanisms, the damage evolution model and single fiber unit model are proposed to explain the stiffness degradation, inelastic deformation accumulation, and elastic deformation. According to the stiffness degradation law, the damage evolution model based on Weibull failure probability is established, which can fit damage-strain curves well. Additionally, the single fiber unit model considering the microscopic mechanisms of matrix cracking, interfacial debonding, and sliding is established. In the model, the stress distributions before and after loading and unloading are analyzed to obtain the elastic strain and inelastic strain formulas of the composite that can perfectly fit the experimental results (R-2 > 99.9%). Because the model reflects the deformation mechanisms of the composites in a much more simplified way, the deformation and damage law of the composite can be well predicted with basic macroscopic parameters such as the composition of the composite, the elastic modulus of the fiber, matrix, and composite, the strength of the matrix and the residual thermal stress of the matrix