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Titanium sesquioxide (Ti2O3) nanopowders have been successfully synthesized using TiCl4 assisted hydrogen reduction method from P25 (TiO2) powders at 970 °C. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy reveal its high purity. The temperature dependent XRD, resistance, and infrared absorption investigations exhibit Z-shaped curves (cell parameter a, resistance, and infrared transmittance) indicating the semiconductor-metal transition (SMT) in the range of 135-220 °C. With prolonging the annealing time, the starting temperature of SMT is found to move toward the low-temperature side, and this was also discussed. The c/a ratio alteration is considered to result in the modulation of property. Besides, the results are verified comparing with the theoretical calculation of band structure. [ABSTRACT FROM AUTHOR]

NLRC3, a member of the NLR family, has been reported as a negative regulator of inflammatory signaling pathways in innate immune cells. However, the direct role of NLRC3 in modulation of CD4+ T-cell responses in infectious diseases has not been studied. In the present study, we showed that NLRC3 plays an intrinsic role by suppressing the CD4+ T cell phenotype in lung and spleen, including differentiation, activation, and proliferation. NLRC3 deficiency in CD4+ T cells enhanced the protective immune response against Mycobacterium tuberculosis infection. Finally, we demonstrated that NLRC3 deficiency promoted the activation, proliferation, and cytokine production of CD4+ T cells via negatively regulating the NF-κB and MEK-ERK signaling pathways. This study reveals a critical role of NLRC3 as a direct regulator of the adaptive immune response and its protective effects on immunity during M. tuberculosis infection. Our findings also suggested that NLRC3 serves as a potential target for therapeutic intervention against tuberculosis. [ABSTRACT FROM AUTHOR]

In Mycobacterium tuberculosis-infected macrophages, cyclooxygenase-2 (COX-2) expression considerably increases to defend the body against mycobacteria by regulating adaptive immunity and restoring the mitochondrial inner membrane. Moreover, in cancer cells, COX-2 enhances the autophagy machinery, an important bactericidal mechanism. However, the association between M. tuberculosis-induced COX-2 and autophagy-mediated antimycobacterial response has not been explored. Here, COX-2 expression silencing reduced the autophagy and bactericidal activity against intracellular M. tuberculosis, while COX-2 overexpression reversed the above effects. In addition, enhancement of bactericidal activity was suppressed by inhibiting autophagy in COX-2-overexpressing cells, indicating that COX-2 accelerated mycobacterial elimination by promoting autophagy. Furthermore, the regulatory effects of COX-2 on autophagy were mediated by its catalytic products, which functioned through inhibiting the protein kinase B/mammalian target of rapamycin pathway. Thus, COX-2 contributes to host defense against mycobacterial infection by promoting autophagy, establishing the basis for development of novel therapeutic agents against tuberculosis by targeting COX-2. [ABSTRACT FROM AUTHOR]

Chalcogenide thin films are exciting candidates for electronic applications such as spintronic devices, non-volatile memories and thermoelectric materials. To achieve such applications the understanding of their thin film growth is of paramount importance. In this work the epitaxy of exemplary chalcogenides Sb2Te3 and GeTe on different surfaces of Si(111) with atomically sharp interfaces is presented and compared using plan-view transmission electron microscopy and electron diffraction. It is shown that depending on the monolayer surface termination the resulting films present drastic differences in terms of film morphology and crystallinity. In particular, a profound difference is found between the films grown on H-passivated and Sb-passivated surfaces. In both cases, the out-of-plane texture is strongly c-axis oriented, but the case of Si(111)–H shows the frequent occurrence of random in-plane twist for both films, while for Si(111)–Sb this is strongly suppressed. The role of the substrate-film interface for the epitaxy is discussed and the consequences for the properties of the films are highlighted. In general, the insights of these results shed light on chalcogenide thin film growth for topological insulator, ferroelectric, thermoelectric and phase-change materials research. [ABSTRACT FROM AUTHOR]

In the present work, GeTe and Sb2Te3 van der Waals bonded superlattices epitaxially grown by molecular beam epitaxy are investigated. These structures are grown on passivated Si substrates, resulting in one single epitaxial domain and its twinned domain, both sharing the same out-of-plane orientation. Supported by X-ray diffraction and Raman spectroscopy, attention is called to the thermodynamically driven tendency of GeTe and Sb2Te3 to intermix into a Ge-Sb-Te (GST) alloy at the interfaces. A growth model is proposed to explain how these GST structures are formed. [ABSTRACT FROM AUTHOR]

A novel α-Fe2O3/graphene composite is prepared by a simple in situ wet chemistry approach. The α-Fe2O3 particles with diameter around 130 nm are homogeneously anchored on graphene nanosheets to form a 3D quasi-laminated architecture. Such a well-organized flexible structure can offer sufficient void space to facilitate the electrolyte penetration, alleviate the effect of the volume change of α-Fe2O3 particles and avoid particle–particle aggregation during lithium insertion/desertion. In addition, graphene not only improves the electric conductivity of the composite electrode but also maintains the structural integrity of the composite electrode during long-term cycling. As anode material for Li-ion batteries, the α-Fe2O3/graphene composite electrode exhibits a stable capacity of 742 mAh g−1 up to 50 cycles. The synthesis technique is suitable for practical large-scale production of graphene-based metal oxide composites as advanced electrode materials for rechargeable Li-ion batteries. [ABSTRACT FROM AUTHOR]

Motivated by the recently discovered superconductivity in Sr-doped nickelate oxides NdNiO2 reduced from NdNiO3 in experiments, we predict a Mott multiferroic BiNiO2 that may be obtained from BiNiO3. There is a ferroelectric structural transition for BiNiO2 from the nonpolar phase to the polar phase with the P4mm space group, which is driven by the lone pair on Bi. The lowest energy ground-state for polar BiNiO2 is a Hubbard Mott insulator with the G-type antiferromagnetic spin configurations. The replacement of Nd by Bi serves as a connecting link between a parent compound of high-temperature superconductor and a Mott multiferroic. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) has become widespread in China particularly the highly pathogenic porcine reproductive and respiratory syndromes (HP-PRRSV), NADC30, and NADC34 strains, and has posed a threat to the swine industry for over 20 years. To monitor genetic variation in PRRSV-2 GP3 strains in China, we analyzed 618 strains isolated between 1996 to 2023 and constructed phylogenetic trees. Additionally, 60 selected strains were used to analyze nucleotide and amino acid homology. PRRSV GP3 gene exhibited nucleotide identity ranging from 78.2% to 100.0% and amino acid similarity ranging from 74.9% to 99.6%. The GP3 gene in the 60 selected strains consisted of 254 amino acids, and amino acid mutations in the strains primarily occurred in B-cell epitopes, T-cell epitopes, and highly variable regions. The glycosylation sites of the strains used for amino acid sequence comparisons remained unaltered, except for the N 29 site in the GD20220303-2022 strain. PRRSV-2 strains in China belong to lineages 1, 3, 5, and 8. Recombination analysis detected two recombination events, involving lineages 1 and 8. In conclusion, this study investigated multiple strains of the PRRSV-2 GP3 gene to explore the prevalence and genetic diversity of the GP3 gene in China from a gene family perspective. The results of the analyses provide a basis for clinical prevention strategies and vaccine development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Lv, Zheng, Liu, Li, Luo, Zhang, Sha, Wang, Kong and Zhao.)

Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious disease caused by the porcine reproductive and respiratory syndrome virus (PRRSV). PRRSV exhibits genetic diversity and complexity in terms of immune responses, posing challenges for eradication. The nucleocapsid (N) protein of PRRSV, an alkaline phosphoprotein, is important for various biological functions. This review summarizes the structural characteristics, genetic evolution, impact on PRRSV replication and virulence, interactions between viral and host proteins, modulation of host immunity, detection techniques targeting the N protein, and progress in vaccine development. The discussion provides a theoretical foundation for understanding the pathogenic mechanisms underlying PRRSV virulence, developing diagnostic techniques, and designing effective vaccines., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zheng, Li, Luo, Sha, Zhang, Wang, Kong, Liao and Zhao.)

The aim of this study was to screen the active regions and transcription factor binding sites in the promoter of the CBD103 gene related to Arctic fox coat color, and to provide a basis for revealing the molecular genetic mechanism of CBD103 gene regulating the coat color formation. The 5'-flanking region fragment 2 123 bp of Arctic fox CBD103 gene was cloned, and 4 truncated promoter reporter vectors of different lengths were constructed. The promoter activity was detected by the dual-luciferase reporter assay system. Point mutations were performed on the 3 predicted specificity protein 1 (Sp1) transcription factor binding sites in the highest promoter active region, and 3 mutant vectors were constructed. The activity was then detected by the dual-luciferase reporter assay system. The results showed that the region 1 656 (-1 604/+51) had the highest activity in the 4 truncated promoters of different lengths, and the promoter activity of the three mutant vectors constructed in this region were significantly lower than that of the wild type (fragment 1 656). The region of -1 604 /+51 was the core promoter region of CBD103 gene in Arctic fox and -1 552/-1 564, -1 439/-1 454 and -329/-339 regions were positive regulatory regions. This study successfully obtained the core promoter region and positive regulation regions of the Arctic fox CBD103 gene, which laid a foundation for further study on the molecular genetic mechanism of this gene regulating Arctic fox coat color.

Phase change materials such as pseudobinary GeTe-Sb 2 Te 3 (GST) alloys are an essential part of existing and emerging technologies. Here, we investigate the electrical and optical properties of epitaxial phase change materials: α-GeTe, Ge 2 Sb 2 Te5 (GST225), and Sb 2 Te 3 . Temperature-dependent Hall measurements reveal a reduction of the hole concentration with increasing temperature in Sb 2 Te 3 that is attributed to lattice expansion, resulting in a non-linear increase of the resistivity that is also observed in GST225. Fourier transform infrared spectroscopy at room temperature demonstrates the presence of electronic states within the energy gap for α-GeTe and GST225. We conclude that these electronic states are due to vacancy clusters inside these two materials. The obtained results shed new light on the fundamental properties of phase change materials such as the high dielectric constant and persistent photoconductivity and have the potential to be included in device simulations.

Objective: To study the relationship between HLA allele frequencies in peripheral blood mononuclear cells (PBMCs) and the susceptibility to tuberculosis in southern Chinese population., Methods: The polymorphisms of HLA-A and HLA-DRB1 loci in the PBMCs were analyzed in 294 patients with active tuberculosis using polymerase chain reaction-sequence based typing (PCT-SBT). The allele frequencies in the patients were compared with the data from 644 control southern Chinese subjects obtained from the online database Allele Frequencies in Worldwide Population., Results: The frequencies of HLA-A * 0101 and HLA-DRB1 * 1454 alleles in the patient cohort with pulmonary tuberculosis were significantly higher than those in the control group (2.4% vs 0.6%, χ 2 =10.788, P =0.001, P c =0.016; 7.5% vs 0%, χ 2 =69.850, P < 0.0001); the frequencies of HLA-DRB1 * 1202 and HLA-DRB1 * 1401 alleles were significantly lower in this patient cohort than in the control group (10.4% vs 16.1%, χ 2 =9.845, P =0.002, P c =0.044; 0% vs 3.1%, χ 2 =18.520, P < 0.001)., Conclusions: The frequencies of HLA-A and HLA-DRB1 alleles are correlated with the susceptibility to active tuberculosis in this southern Chinese population. HLA-A * 0101, HLA-DRB1 * 1454 and the other 3 alleles are likely susceptible genes to tuberculosis, while HLA-DRB1 * 1202, HLA-DRB1 * 1401 and the other 4 alleles can be protective genes in this population.

In this review we focus on methods that are used to trap and release on command therapeutic drugs from mesoporous silica nanoparticles (MSNs). The pores in the MSNs are large enough to accommodate a wide range of cargo molecules such as anticancer and antibiotic drugs and yet small enough to be blocked by a variety of bulky molecules that act as caps. The caps are designed to be tightly attached to the pore openings and trap the cargo molecules without leakage, but upon application of a designed stimulus detach from the nanoparticles and release the cargo. Of special emphasis in this review are nanomachines that respond to stimuli administered from external sources such as light or magnetic fields, or from chemical stimuli produced by the biological system such as a general change in pH or redox potential, or a highly specific chemical produced by a cancer cell or infectious bacterium. The goal is to release a high local concentration of the cargo only where and when it is needed, thus minimizing off-target side effects. We discuss sophisticated reversible nanomachines but also discuss some useful caps that simply break off from the nanoparticles in response to the selected stimulus. Many ingenious systems have been and are being designed; we primarily highlight those that have been demonstrated to operate in vitro and/or in vivo. In most cases the closed MSNs are endocytosed by diseased or infected cells and opened inside the cells to release the drugs. We begin with an overview of the nanoparticles and nanomachines and then present examples of drug release triggered by internal chemical stimuli from the organism and finally by external light and magnetic field stimuli., (© 2018 Elsevier Inc. All rights reserved.)

Phase-change materials based on GeSbTe show unique switchable optoelectronic properties and are an important contender for next-generation non-volatile memories. Moreover, they recently received considerable scientific interest, because it is found that a vacancy ordering process is responsible for both an electronic metal-insulator transition and a structural cubic-to-trigonal transition. GeTe-Sb 2 Te 3 based superlattices, or specifically their interfaces, provide an interesting platform for the study of GeSbTe alloys. In this work such superlattices have been grown with molecular beam epitaxy and they have been characterized extensively with transmission electron microscopy and X-ray diffraction. It is shown that the van der Waals gaps in these superlattices, which result from vacancy ordering, are mobile and reconfigure through the film using bi-layer defects and Ge diffusion upon annealing. Moreover, it is shown that for an average composition that is close to GeSb 2 Te 4 a large portion of 9-layered van der Waals systems is formed, suggesting that still a substantial amount of random vacancies must be present within the trigonal GeSbTe layers. Overall these results illuminate the structural organization of van der Waals gaps commonly encountered in GeSbTe alloys, which are intimately related to their electronic properties and the metal-insulator transition.

Epithelial ovarian cancer (EOC) is the most deadly gynecologic malignancy on account of its late stage at diagnosis and frequency of drug resistant recurrences. Novel therapies to overcome these barriers are urgently needed. TWIST is a developmental transcription factor reactivated in cancers and linked to angiogenesis, metastasis, cancer stem cell phenotype, and drug resistance, making it a promising therapeutic target. In this work, we demonstrate the efficacy of TWIST siRNA (siTWIST) and two nanoparticle delivery platforms to reverse chemoresistance in EOC models. Polyamidoamine dendrimers and mesoporous silica nanoparticles (MSNs) carried siTWIST into target cells and led to sustained TWIST knockdown in vitro. Mice treated with cisplatin plus MSN-siTWIST exhibited lower tumor burden than mice treated with cisplatin alone, with most of the effect coming from reduction in disseminated tumors. This platform has potential application for overcoming the clinical challenges of metastasis and chemoresistance in EOC and other TWIST overexpressing cancers., (Copyright © 2016 Elsevier Inc. All rights reserved.)