Fe3O4-Cy5.5-trastuzumab magnetic nanoparticles for magnetic resonance/near-infrared imaging targeting HER2 in breast cancer.

This study developed a probe Fe3O4-Cy5.5-trastuzumab with fluorescence and magnetic resonance imaging functions that can target breast cancer with high HER2 expression, aiming to provide a new theoretical method for the diagnosis of early breast cancer. Fe3O4-Cy5.5-trastuzumab nanoparticles were combined with Fe3O4for T2imaging and Cy5.5 for near-infrared imaging, and coupled with trastuzumab for HER2 targeting. We characterized the nanoparticles used transmission electron microscopy, hydration particle size, Zeta potential, UV and Fourier transform infrared spectroscopy, and examined its magnetism, fluorescence, and relaxation rate related properties. CCK-8 and blood biochemistry analysis evaluated the biosafety and stability of the nanoparticles, and validated the targeting ability of Fe3O4-Cy5.5 trastuzumab nanoparticles throughin vitroandin vivocell and animal experiments. Characterization results showed the successful synthesis of Fe3O4-Cy5.5-trastuzumab nanoparticles with a diameter of 93.72 ± 6.34 nm. The nanoparticles showed a T2relaxation rate 42.29 mM-1s-1, magnetic saturation strength of 27.58 emg g-1. Laser confocal and flow cytometry uptake assay showed that the nanoparticles could effectively target HER2 expressed by breast cancer cells. As indicated byin vitroandin vivostudies, Fe3O4-Cy5.5-trastuzumab were specifically taken up and effectively aggregated to tumour regions with prominent NIRF/MR imaging properties. CCK-8, blood biochemical analysis and histological results suggested Fe3O4-Cy5.5-trastuzumab that exhibited low toxicity to major organs and goodin vivobiocompatibility. The prepared Fe3O4-Cy5.5-trastuzumab exhibited excellent targeting, NIRF/MR imaging performance. It is expected to serve as a safe and effective diagnostic method that lays a theoretical basis for the effective diagnosis of early breast cancer. This study successfully prepared a kind of nanoparticles with near-infrared fluorescence imaging and T2imaging properties, which is expected to serve as a new theory and strategy for early detection of breast cancer.

Genome-wide identification of GATA transcription factor family and the effect of different light quality on the accumulation of terpenoid indole alkaloids in Uncaria rhynchophylla.

Uncaria rhynchophylla is an evergreen vine plant, belonging to the Rubiaceae family, that is rich in terpenoid indole alkaloids (TIAs) that have therapeutic effects on hypertension and Alzheimer's disease. GATA transcription factors (TF) are a class of transcription regulators that participate in the light response regulation, chlorophyll synthesis, and metabolism, with the capability to bind to GATA cis-acting elements in the promoter region of target genes. Currently the charactertics of GATA TFs in U. rhynchophylla and how different light qualities affect the expression of GATA and key enzyme genes, thereby affecting the changes in U. rhynchophylla alkaloids have not been investigated. In this study, 25 UrGATA genes belonging to four subgroups were identified based on genome-wide analysis. Intraspecific collinearity analysis revealed that only segmental duplications were identified among the UrGATA gene family. Collinearity analysis of GATA genes between U. rhynchophylla and four representative plant species, Arabidopsis thaliana, Oryza sativa, Coffea Canephora, and Catharanthus roseus was also performed. U. rhynchophylla seedlings grown in either red lights or under reduced light intensity had altered TIAs content after 21 days. Gene expression analysis reveal a complex pattern of expression from the 25 UrGATA genes as well as a number of key TIA enzyme genes. UrGATA7 and UrGATA8 were found to have similar expression profiles to key enzyme TIA genes in response to altered light treatments, implying that they may be involved in the regulation TIA content. In this research, we comprehensively analyzed the UrGATA TFs, and offered insight into the involvement of UrGATA TFs from U. rhynchophylla in TIAs biosynthesis.

Evaluation of Reference Genes for Normalizing RT-qPCR and Analysis of the Expression Patterns of WRKY1 Transcription Factor and Rhynchophylline Biosynthesis-Related Genes in Uncaria rhynchophylla.

Uncaria rhynchophylla (Miq.) Miq. ex Havil, a traditional medicinal herb, is enriched with several pharmacologically active terpenoid indole alkaloids (TIAs). At present, no method has been reported that can comprehensively select and evaluate the appropriate reference genes for gene expression analysis, especially the transcription factors and key enzyme genes involved in the biosynthesis pathway of TIAs in U. rhynchophylla. Reverse transcription quantitative PCR (RT-qPCR) is currently the most common method for detecting gene expression levels due to its high sensitivity, specificity, reproducibility, and ease of use. However, this methodology is dependent on selecting an optimal reference gene to accurately normalize the RT-qPCR results. Ten candidate reference genes, which are homologues of genes used in other plant species and are common reference genes, were used to evaluate the expression stability under three stress-related experimental treatments (methyl jasmonate, ethylene, and low temperature) using multiple stability analysis methodologies. The results showed that, among the candidate reference genes, S-adenosylmethionine decarboxylase (SAM) exhibited a higher expression stability under the experimental conditions tested. Using SAM as a reference gene, the expression profiles of 14 genes for key TIA enzymes and a WRKY1 transcription factor were examined under three experimental stress treatments that affect the accumulation of TIAs in U. rhynchophylla. The expression pattern of WRKY1 was similar to that of tryptophan decarboxylase (TDC) under ETH treatment. This research is the first to report the stability of reference genes in U. rhynchophylla and provides an important foundation for future gene expression analyses in U. rhynchophylla. The RT-qPCR results indicate that the expression of WRKY1 is similar to that of TDC under ETH treatment. It may coordinate the expression of TDC, providing a possible method to enhance alkaloid production in the future through synthetic biology.

Vision measuring technology for the position degree of a hole group.

The hole is one of the most important geometric elements in mechanical parts. The center distance of a hole group measurement method based on machine vision is proposed for solving the influence of perspective distortion and improving the applicability of vision systems. In the method, the plane equation of the measured plane is obtained by the line structured light vision technology, and the process is free from the constraints of the calibration plate. In order to eliminate the effect of projection distortion on the measurement accuracy, a local coordinate system is established on the plane of the measured hole group, the hole diameter, and the center distance of the hole group, which could be calculated by the local coordinates of the hole edge points. In the experiment, the flange is taken as the measured object, the distances between the holes on the flange are obtained by the method proposed in this paper, and the measurement results compared with the data are obtained by a coordinate measuring machine (CMM). The experimental results show that the average measurement error of center distance is 0.0739 mm, and the standard deviation is 0.0489 mm.

Genome-Wide Identification and Expression Analysis of WRKY Transcription Factors in Siraitia siamensis.

WRKY transcription factors, as the largest gene family in higher plants, play an important role in various biological processes including growth and development, regulation of secondary metabolites, and stress response. In this study, we performed genome-wide identification and analysis of WRKY transcription factors in S. siamensis. A total of 59 SsWRKY genes were identified that were distributed on all 14 chromosomes, and these were classified into three major groups based on phylogenetic relationships. Each of these groups had similar conserved motifs and gene structures. We compared all the S. siamensis SsWRKY genes with WRKY genes identified from three diverse plant species, and the results implied that segmental duplication and tandem duplication play an important roles in the evolution processes of the WRKY gene family. Promoter region analysis revealed that SsWRKY genes included many cis-acting elements related to plant growth and development, phytohormone response, and both abiotic and biotic stress. Expression profiles originating from the transcriptome database showed expression patterns of these SsWRKY genes in four different tissues and revealed that most genes are expressed in plant roots. Fifteen SsWRKY genes with low-temperature response motifs were surveyed for their gene expression under cold stress, showing that most genes displayed continuous up-regulation during cold treatment. Our study provides a foundation for further study on the function and regulatory mechanism of the SsWRKY gene family.

One-Step Formation of Low Work-Function, Transparent and Conductive MgFx Oy Electron Extraction for Silicon Solar Cells.

The development of high-performance dopant-free silicon solar cells is severely bottlenecked by opaque electron selective contact. In this paper, high transmittance (80.5% on glass) and low work function (2.92 eV) lithium fluoride (LiFx )/MgFx Oy electron contact stack by tailoring the composition of MgFx Oy hybrid film is reported. This hybrid structure exhibits a high conductivity (2978.4 S cm-1 ) and a low contact resistivity (2.0 mΩ cm2 ). The element profile of LiFx /MgFx Oy contact is measured and the reaction kinetics is analyzed. As a proof-of-concept, this electron selective contact is applied for dopant-free silicon solar cells. An impressive efficiency of 21.3% is achieved on dopant-free monofacial solar cell with molybdenum oxide (MoOx )/zinc-doped indium oxide (IZO) hole contact. An efficiency bifaciality of 71% is obtained for dopant-free bifacial solar cell with full-area LiFx /MgFx Oy /ITO (tin-doped indium oxide) transparent electron contact. It is the highest efficiency bifaciality so far for dopant-free bifacial solar cells to the best knowledge. Both cell configurations with LiFx /MgFx Oy contacts show excellent environment stability. The cell efficiency maintains more than 95% of its initial value after keeping in air for 1500 h. This work provides a new idea to achieve transparent electron contact, showing a great potential for high-efficiency and low-cost optoelectronic devices.

A Simple Approach for Generating Random Aggregate Model of Concrete Based on Laguerre Tessellation and Its Application Analyses.

Generating random aggregate models (RAMs) plays a key role in the mesoscopic modelling of concrete-like composite materials. The arbitrary geometry, wide gradation, and high volume ratio of aggregates pose a great challenge for fast and efficient numerical construction of concrete meso-structures. This paper presents a simple strategy for generating RAMs of concrete based on Laguerre tessellation, which mainly consists of three steps: tessellation, geometric smoothing, and scaling. The computer-assisted design (CAD) file of RAMs obtained by the proposed approach can be directly adopted for the construction of random numerical concrete samples. Combined with the image-based octree meshing algorithm, the scaled boundary finite element method (SBFEM) was adopted for an automatic stress analysis of mass concrete samples, and a parametric study was conducted to investigate the meso-structural effects on concrete elasticity properties. The modelling results successfully reproduced the increasing trend of concrete elastic modulus with the grading of coarse aggregates in literature test data and demonstrate the effectiveness of the proposed strategy.

Measurement of yield and spectrum of secondary electron emission and their characteristics under modification of conductive materials.

Surface modification technique of secondary electron emission (SEE) characteristics of materials, which is utilized to suppress or promote the SEE from material surface under electron bombardment, has extensive applications in a variety of fields. Measurement of the secondary electron yield (SEY) and the secondary electron spectrum (SES) before and after surface modification is essential for the evaluation of effectiveness and the investigation of mechanism of material modification. A SEY and SES measurement system is reported in this article. The comparative measurements of the total SEY, the true SEY, the backscattered electron yield, and the SES of nickel and free-standing vertical graphene, which was grown in situ on the surface of nickel substrate by plasma enhanced chemical vapor deposition, were performed using this system. The measurement results demonstrate that this system could facilitate the study of surface modification on the SEE characteristics of conductive materials.