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This study demonstrates a novel method to improve the density, interface bonding strength and mechanical properties of the B4Cp/Al composites by directly adding TiB2 to the material. Specifically, the (TiB2p+B4Cp)/Al composites with different TiB2 contents were successfully fabricated by ball milling (BM) and microwave sintering (MS). The results indicate that the developed (TiB2p+B4Cp)/Al possess a clean interface, with the absence of any reaction, thus, confirming microwave sintering as one of the preferred ways to prepare the (TiB2p+B4Cp)/Al composites. On adding TiB2, the densification in the microstructure is noted to initially increase, followed by a decrease. Overall, the TiB2 and B4C particles are noted to synergistically improve the densification as well as ameliorate the interfaces and microstructure. As a result, the optimized composites exhibit the compactness and Vickers hardness as high as 94.6% and 153.42HV0.3 respectively. The highest value of the compressive strength is determined to be 578.71 MPa at 50.0%. Further, no macroscopic fracture is noted to occur after 50% compression strain.

This study aims to improve the non-contact measurement accuracy of roughness of small samples. Therefore, machine vision and virtual sample generation technology are used to detect the roughness of small sample bearing steel (GCr15) in this study. The surface roughness of different specimens is tested with a contact roughness detector. Image acquisition is carried out on the specimen, histogram equalization image enhancement preprocessing is carried out on the image, and sample capacity expansion is carried out on the basis of data enhancement. On this basis, the gray-level co-occurrence matrix (GLCM) is used to extract the image texture features, and a linear regression model of roughness and Energy, Entropy, Homogeneity, Contrast and Correlation is established. Artificial neural networks (ANNs) is used to classify and predict their surface roughness, train the original samples and virtual samples respectively, and compare their prediction accuracy. The results show that the precision of the virtual samples based on resampling and singular value decomposition(SVD) are 10.13% and 21.21% higher than that of the original samples, respectively, and the average error between the predicted value and the measured value of visual roughness is 3.4%. Therefore, the machine vision and virtual sample generation technology are combined to achieve acceptable surface roughness detection of small samples, which provides a theoretical basis for online detection in gear processing.

Trop2, also known as trophoblast antigen 2, is a transmembrane glycoprotein. It is therapeutically targeted in cancer due to its over-expression in a variety of human carcinomas. To develop a promising therapeutic anti-tumor agent, we generated BL-M02D1, an anti-Trop2-Ed-04 ADC. It is comprised of a novel monoclonal antibody against Trop2 (hu4D3), a cathepsin B cleavable linker, and a novel topoisomerase I inhibitor agent (Ed-04). The novel Ed-04 is a derivative of the alkaloid camptothecin and mediates cell cycle arrest at the S phase and subsequent apoptosis. BL-M02D1 achieves a high drug-to-antibody-ratio (DAR=8) with a highly stable linker. The antitumor efficacy of BL-M02D1 was evaluated in comparison to a commercialized Trop2-targeting ADC, IMMU-132, in xenograft tumor models. BL-M02D1 exhibited stronger tumor inhibition capacity than IMMU-132 at lower doses in the gastric cancer cell line NCI-N87, the breast cancer cell line MDA-MB-231, and the non-small cell lung cancer cell line HCC827 xenograft models. BL-M02D1 exhibited potent bystander effects, exemplified by strong tumor inhibition in a heterogeneous xenograft model of Trop2-positive and Trop2-negative tumor cells (A431 and SW620). This characteristic of BL-M02D1 was also compared to IMMU-132. In the heterogeneous Trop2 xenograft model (A431 and SW620), BL-M02D1 exhibited higher tumor inhibition capacity than IMMU-132, indicating that BL-M02D1 possess a more potent bystander effect than IMMU-132. In summary, these studies suggest BL-M02D1, a novel Trop2-targeting ADC, is potentially more efficacious in the treatment of Trop2-expressing carcinomas than IMMU-132. The clinical phase I has been progressing and the available data exhibit excellent efficacy in breast cancer therapy with manageable toxicity. Citation Format: Yong Zhang, Weili Wan, Shi Zhuo, Lan Chen, Gangrui Li, Shuwen Zhao, Jahan Salar Khalili, Sa Xiao, Yongqi Yan, Xuejiao Shen, Yi Zhu. BL-M02D1, a novel Trop2-targeting ADC, demonstrates robust anti-tumor efficacy in preclinical evaluation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2644.

HER2 is a member of the epidermal growth factor receptor family. Activation of the HER2 signaling pathway has been shown to strongly promote carcinogenesis. It is therapeutically targeted in cancer owing to its overexpression and pathway dependence in a variety of human carcinomas, especially human breast cancers. We created a promising therapeutic anti-tumor agent, BL-M07D1, an anti-HER2-Ed-04 ADC. It is comprised of a humanized anti-HER2 antibody Trastuzumab, a cathepsin B cleavable linker, and a novel topoisomerase I inhibitor agent (Ed-04), which is a derivative of the alkaloid camptothecin, driving cell cycle arrest at the S phase and subsequent apoptosis. The BL-M07D1 drug-to-antibody-ratio is 8:1 (DAR=8), similar to Trastuzumab Deruxotecan (DS-8201), while possessing a more stable linker. To evaluate the pharmacological potential of BL-M07D1, xenograft tumor inhibition assays were used to compare BL-M07D1 with the commercialized HER2-targeting ADCs, T-DM1 and DS-8201, which have been approved worldwide for patients with HER2-expressing tumors. Results from the in vivo murine studies show that BL-M07D1 has strong tumor inhibition effects in multiple cell line-derived xenograft (CDX) tumor models. 1) BL-M07D1 exhibited better anti-tumor efficacy than DS-8201 in CDX with low HER2 expression, human epidermal cancer A431 and human non-small cell lung cancer NCI-H1975. Both models are considered be T-DM1-insensitive. 2) BL-M07D1 exhibited better anti-tumor efficacy in comparison to either T-DM1 or DS-8201 in a CDX with JIMT-1, a HER2-positive human breast cancer cell line. 3) BL-M07D1 exhibits potent bystander effects in a heterogeneous xenograft model of HER2-positive and HER2-negative tumor cells composed of NCI-N87 and MDA-MB-468 cells. In this model, BL-M07D1 exhibited stronger tumor inhibition than T-DM1, consistent with bystander effects that are also exhibited by DS-8201. In conclusion, in vivo studies suggest that BL-M07D1, a novel HER2-targeting ADC, is potentially more efficacious in a broader patient population than T-DM1, and mediate superior anti-tumor efficacy than DS-8201. The clinical phase I is under way and the available data exhibit excellent efficacy in breast cancer therapy with acceptable tolerability. Citation Format: Weili Wan, Shuwen Zhao, Shi Zhuo, Yong Zhang, Lan Chen, Gangrui Li, Jahan Salar Khalili, Sa Xiao, Yongqi Yan, Xuejiao Shen, Yi Zhu. BL-M07D1, a novel HER2-targeting ADC, demonstrates potent anti-tumor efficacy in preclinical pharmacodynamic models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2643.

Confronting the challenge of the outbreak of COVID‐19 should sharpen our focus on global drug access as a key issue in antiviral therapy testing. The testing and adoption of effective therapies for novel coronaviruses are hampered by the challenge of conducting controlled studies during a state of emergency. The access to direct antiviral drugs, such as ribavirin, that have an existing inventory and reliable supply chain may be a priority consideration for therapies developed for the 2019‐nCoV infection outbreaks and any strain variants that may emerge. On the basis of the direct antiviral activity of ribavirin against 2019‐nCoV in vitro and evidence for potency enhancement strategies developed during the prior SARS and MERS outbreaks, ribavirin may significantly impact our ability to end the lingering outbreaks in China and slow outbreaks in other countries. The apparent COVID‐19 pandemic provides an opportunity to follow dosage guidelines for treatment with ribavirin, test new therapeutic concepts, and conduct controlled testing to apply the scientific rigor required to address the controversy around this mainstay of antiviral therapy., Highlights The multimodal anti‐viral mechanisms of action of ribavirin are described.Treatment of novel coronaviruses with ribavirin during SARS and MERS outbreaks are detailed.Challenges in evaluation of drug efficacy from viral outbreaks are described.Registered clinical trials to evaluate ribavirin for COVID‐19 are listed.

A thin layer of polydopamine (PDA) was coated on the surface of cellulose nanocrystals (CNCs) by the self-polymerization of dopamine (DA) in water to improve the hydrophilicity and lipophilicity of CNCs. Then, the CNCs coated with PDA (PDA@CNCs) were blended with pore forming agent and cellulose acetate (CA), and the CA composite membrane reinforced by PDA@CNCs (PDA@CNCs/CA) was prepared by solution phase transformation method. The effects of PDA@CNCs content on the filtration performance, antifouling ability and mechanical properties of the composite membrane were studied. The results show that adding a small amount of PDA@CNCs can significantly improve the filtration capacity, antifouling performance and tensile strength of CA membrane. When the content of PDA@CNCs was 4 wt%, the hydraulic permeability, flux recovery ratio and tensile strength of PDA@CNCs/CA composite membrane increased by 33%, 15% and 76%, respectively. Simple DA modification improves the lipophilicity and dispersion of CNCs, enhances the binding force between CNCs filler and CA matrix, and improves the performance of CA composite membrane, thus widen the industrial application of CA materials, and shows a broad application prospect in the field of biological separation membrane and water treatment membrane.

Hydrocarbon oil is used to lubricate the spindle motor as well as the pivot actuator arm in current hard disk drives. Previous investigations using molecular dynamics have shown that hydrocarbon oil can contaminate the head-disk interface. In this paper, an experimental study is conducted to investigate the mechanism of hydrocarbon oil contamination on the disk surface using contact angle measurements, atomic force microscopy (AFM), ellipsometry, and gas chromatography mass spectrometry (GC-MS).Copyright © 2016 by ASME

DNase I hypersensitive sites (DHSs) are markers of regulatory DNA and have underpinned the discovery of all classes of cis-regulatory elements including enhancers, promoters, insulators, silencers and locus control regions. Here we present the first extensive map of human DHSs identified through genome-wide profiling in 125 diverse cell and tissue types. We identify ∼2.9 million DHSs that encompass virtually all known experimentally validated cis-regulatory sequences and expose a vast trove of novel elements, most with highly cell-selective regulation. Annotating these elements using ENCODE data reveals novel relationships between chromatin accessibility, transcription, DNA methylation and regulatory factor occupancy patterns. We connect ∼580,000 distal DHSs with their target promoters, revealing systematic pairing of different classes of distal DHSs and specific promoter types. Patterning of chromatin accessibility at many regulatory regions is organized with dozens to hundreds of co-activated elements, and the transcellular DNase I sensitivity pattern at a given region can predict cell-type-specific functional behaviours. The DHS landscape shows signatures of recent functional evolutionary constraint. However, the DHS compartment in pluripotent and immortalized cells exhibits higher mutation rates than that in highly differentiated cells, exposing an unexpected link between chromatin accessibility, proliferative potential and patterns of human variation. An extensive map of human DNase I hypersensitive sites, markers of regulatory DNA, in 125 diverse cell and tissue types is described; integration of this information with other ENCODE-generated data sets identifies new relationships between chromatin accessibility, transcription, DNA methylation and regulatory factor occupancy patterns. This paper describes the first extensive map of human DNaseI hypersensitive sites — markers of regulatory DNA — in 125 diverse cell and tissue types. Integration of this information with other data sets generated by ENCODE (Encyclopedia of DNA Elements) identified new relationships between chromatin accessibility, transcription, DNA methylation and regulatory-factor occupancy patterns. Evolutionary-conservation analysis revealed signatures of recent functional constraint within DNaseI hypersensitive sites.

Fluorite is widely employed as fluxing agent in metallurgy flux, which inevitably leads to serious fluorine pollution. In this work, B2O3 is used as fluxing agent of CaO–based refining flux to substitute for CaF2 so as to decrease the melting temperature and to improve the speed of slag forming and the refining efficiency. The effects of B2O3 on the melting temperature, viscosity and desulfurization capacity of CaO–based refining flux were investigated. The results indicate that the fluxing action of B2O3 is better than that of CaF2 and Al2O3. For the high basicity CaO–based refining flux (mass ratio of CaO/SiO2 is 5.0–8.75), when CaF2 is substituted with B2O3, the melting temperature can be decreased remarkably. Especially, when the mass ratios of CaO/Al2O3 and CaO/SiO2 are in range of 1.1–4.0 and 5.25–8.0, respectively, the flux melting temperature is lower than 1300°C. At the same time, the temperature range, in which the flux viscosity is low, is expanded as well as the stability of flux viscosity varying with temperature is improved obviously. These variations of flux properties are favorable for refining process. The results of experiments on sulphur partition equilibrium between metal and flux indicate that the desulfurization capacity of flux can be improved markedly when CaF2 is substituted with equal mass of B2O3. When 4 mass% B2O3 is employed as fluxing agent and the mass ratio of CaO/Al2O3 is in the range of 1.5–7.0, the final sulfur content of metal can be controlled lower than 0.004%.

Calves were infected intranasally and intratracheally with Newcastle disease virus (NDV), an avian paramyxovirus. Clinical signs, viral replication, and antibody production were evaluated. This study showed that NDV replicated in calves, as evidenced by development of NDV-specific humoral and mucosal antibody responses, but was attenuated in this unnatural host. These results suggest that NDV has the potential for development as a host-range-restricted, intranasal vaccine vector for cattle that lack preexisting immunity to NDV.

Newcastle disease virus (NDV), a member of the family Paramyxoviridae , has a nonsegmented negative-sense RNA genome consisting of six genes (3′-NP-P-M-F-HN-L-5′). The first three 3′-end intergenic sequences (IGSs) are single nucleotides (nt), whereas the F-HN and HN-L IGSs are 31 and 47 nt, respectively. To investigate the role of IGS length in NDV transcription and pathogenesis, we recovered viable viruses containing deletions or additions in the IGSs between the F and HN and the HN and L genes. The IGS of F-HN was modified to contain an additional 96 nt or more or a deletion of 30 nt. Similarly, the IGS of HN-L was modified to contain an additional 96 nt or more or a deletion of 42 nt. The level of transcription of each mRNA species (NP, F, HN, and L) was examined by Northern blot analysis. Our results showed that NDV can tolerate an IGS length of at least 365 nt. The extended lengths of IGSs down-regulated the transcription of the downstream gene and suggested that 31 nt in the F-HN IGS and 47 nt in the HN-L IGS are required for efficient transcription of the downstream gene. The effect of IGS length on pathogenicity of mutant viruses was evaluated in embryonated chicken eggs, 1-day-old chicks, and 6-week-old chickens. Our results showed that all IGS mutants were attenuated in chickens. The level of attenuation increased as the length of the IGS increased. Interestingly, decreased IGS length also attenuated the viruses. These findings can have significant applications in NDV vaccine development.

To determine the role of amino acid sequences of the hemagglutinin-neuraminidase (HN) cytoplasmic tail in Newcastle disease virus (NDV) replication and pathogenicity, we generated recombinant NDVs with a deletion or point mutation in the N-terminal cytoplasmic tail. The first 2-amino-acid deletion in the cytoplasmic tail did not affect the biological characteristics of NDV. However, a 4-amino-acid deletion and the substitution of alanine for serine at position 6 affected cell fusion, pathogenicity, and colocalization of the HN and M proteins of NDV, indicating that these residues of the HN cytoplasmic tail are critical for its specific incorporation into virions.

The hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) is a multifunctional protein that plays a crucial role in virus infectivity. In this study, using the mesogenic strain Beaudette C (BC), we mutated three conserved amino acids thought to be part of the binding/catalytic active site in the HN protein. We also mutated five additional residues near the proposed active site that are nonconserved between BC and the avirulent strain LaSota. The eight recovered NDV HN mutants were assessed for effects on biological activities. While most of the mutations had surprisingly little effect, mutation at conserved residue Y526 reduced the neuraminidase, receptor binding, and fusion activities and attenuated viral virulence in eggs and young birds.

To determine the role of untranslated regions (UTRs) in replication and pathogenesis of Newcastle disease virus (NDV), we generated recombinant viruses with deletions in 5′ and 3′ UTRs of the HN mRNA. Deletion of any HN UTR did not noticeably affect in vitro replication of these viruses. However, complete deletion of the 5′ UTR of the HN gene decreased the HN mRNA levels and HN protein contents in virus particles, resulting in attenuation of the virus in chickens. This indicates that the 5′ UTR of HN mRNA plays an important role in replication and pathogenicity of NDV in vivo.

The neonatal Fc receptor for IgG (FcRn) transfers maternal IgG to the offspring and protects IgG from degradation. The FcRn resides in an acidic intracellular compartment, allowing it to bind IgG. In this study, we found the association of FcRn and invariant chain (Ii). The interaction was initiated within the endoplasmic reticulum by Ii binding to either the FcRn H chain alone or FcRn H chain-β2-microglobulin complex and appeared to be maintained throughout the endocytic pathway. The CLIP in Ii was not required for FcRn-Ii association. The interaction was also detected in IFN-γ-treated THP-1, epithelial and endothelial cells, and immature mouse DCs. A truncated FcRn without the cytoplasmic tail was unable to traffic to early endosomes; however, its location in early endosomes was restored by Ii expression. FcRn was also detected in the late endosome/lysosome only in the presence of Ii or on exposure to IFN-γ. In immature human or mouse DCs, FcRn was barely detected in the late endosome/lysosome in the absence of Ii. Furthermore, the cytoplasmic tail of Ii conferred tailless FcRn to route to both the early endosome and late endosome/lysosome in a hybrid molecule. Because the FcRn is expressed in macrophages and DCs or epithelial and endothelial cells where Ii is induced under inflammation and infection, these results reveal the complexity of FcRn trafficking in which Ii is capable of expanding the boundary of FcRn trafficking. Taken together, the intracellular trafficking of FcRn is regulated by its intrinsic sorting information and/or an interaction with Ii chain.

Transcription activator-like effector nucleases (TALEN) are engineered proteins used for precise genome editing by generating specific DNA double strand that are repaired by homologous recombination and by non-homologous end joining. TALENs can be used to study gene regulation by deleting putative regulatory elements in the context of the native chromosome and measuring mRNA synthesis. We designed TALENs to delete individual DNAse I-hypersensitive sites (HS) of the β-globin locus control region (LCR) followed by an assessment of globin gene expression and assessment of epigenetic effects in K562 erythroleukemia cells. The β-globin LCR is composed of five HSs and functions as a powerful regulatory element responsible for appropriate levels of the five β-like globin genes during development. Introduction of plasmid DNA encoding a pair of TALENs and targeting individually the flanking region of the HS2, HS3 and HS4 core elements along with a donor 100 base single-stranded oligonucleotide resulted in the successful deletions of each of the three core elements in K562 cells. Individual K562 cells were seeded to produce clones and the mutations were screened by PCR to identify both heterozygous and homozygous clones. The TALEN-mediated 288 bp HS2 core deletion resulted 32 heterozygous (48.5%) and 6 homozygous clones (9.1%) in a total of 66 clones screened. K562 carries three copies of chromosome 11 emphasizing the robustness of TALEN technology to target each of the alleles. In the 199 bp HS3 core deletion, from 113 clones we identified 28 heterozygous (24.8%) and 3 (2.7%) homozygous clones. Lastly, the 301 bp HS4 core deletion yielded 9 homozygous (5.9%) and 12 heterozygous (7.9%) clones from 151 clones screened. Total RNA was isolated from wild-type K562 cells, and from both the heterozygous and homozygous mutant clones and subjected to RNase Protection analysis to quantitate the levels of globin mRNA. Deletion if the HS3 core in K562 cells in a ∼30% reduction in ε-globin mRNA and 2-fold reduction in γ-globin mRNA. A more dramatic effect on globin expression is observed in the HS2 core deletion, as ε- and γ-globin expression is reduced by 2- and 5-fold, respectively. These results suggest that HS2 contributes the majority of the LCR enhancer function in K562 cells. The HS4 core deletion resulted in a modest ∼20% reduction in both ε- and γ-globin expression. TALENs were designed to knockout trans-acting factors implicated to be involved in globin gene regulation and/or globin switching. TALENs bracketing the gene promoters and the first exon of 25 genes encoding either a transcription factor or histone-modifying enzyme were synthesized and post-transfection PCR screens of the transfected pool of K562 cells resulted in the successful identification of 17 gene knockouts. The 17 target genes are PRMT5, LDB1, EIF2AK3, BCL11A, HBSIL, MYB, SOX6, NFE4, NR2F2, NR2C1, NR2C2, CHTOP, NFE2, DNMT3A, RBBP4, MTA2 and MBD2. Single cell clones have been generated by limited dilution of transfected K562 pools and thus far we have identified heterozygous and homozygous clones of 8 of 17 gene knockouts, importantly all clones were identified without selection. The frequency of identifying the knockout clones, represented by the number of clones screened/ number of heterozygous clones/ number of homozygous clones, are as follows: HBS1L (63/3/0), SOX6 (68/13/2), NFE4 (56/13/7), LBD1 (300/2/0), MBD2 (301/0/1), CHTOP (288/66/6), NFE2 (712/44/5) and NR2C1 (96/40/11). The remaining nine gene knockouts and globin gene expression data will be presented at the meetings. These studies highlight a powerful TALEN-mutagenesis platform for target deletions of both cis- and trans-elements to study globin gene switching. TALENs can be synthesized in several days and the screening of the individual clones for the desired knockouts is completed within two weeks. This highly efficient mutagenesis platform will further our understanding of the molecular basis of globin switching. Disclosures: No relevant conflicts of interest to declare.