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Objective: Sjögren disease (SjD) is an autoimmune condition characterized by the dysfunction of the salivary and lacrimal glands. The study aimed to decipher the pathogenic cell populations and their immunologic pathways in the salivary glands. We further determined the therapeutic effect of inhibiting dedicator of cytokinesis 2 (DOCK2) shared by novel clusters of CD8+ T cells in an SjD mouse model. Methods: This study employed single‐cell RNA sequencing to examine the composition and dynamics of immune cells in the salivary glands of SjD mice. By analyzing the transcriptomic data and employing clustering analysis, a specific target was identified, leading to the treatment of mice with a targeted inhibitor. Results: The results showed diverse immune cell types, including B cells, CD4+ T cells, CD8+ T cells, macrophages, and natural killer cells. We identified specific clusters possessing phenotypic characteristics of immune cell subpopulations, thereby showing specific genes/pathways associated with the disease. The most striking finding was the elevated expression of DOCK2 in CD8+ T cells in the SjD model. This discovery is significant because subsequent treatment with a DOCK2 inhibitor 4‐[3‐(2‐Chlorophenyl)‐2‐propen‐1‐ylidene]‐1‐phenyl‐3,5‐pyrazolidinedione (CPYPP) led to a marked amelioration of SjD signs. Conclusion: The effectiveness of DOCK2 inhibition in alleviating SjD signs highlights the potential of DOCK2 as a therapeutic target, opening new avenues for treatment strategies that could modulate the immune response more effectively in SjD. [ABSTRACT FROM AUTHOR]

Recently, the assembly of van der Waals heterostructures (vdWH) has proved to be an effective strategy to alter the properties and enhance the functionality of multifunctional devices based on 2D materials. Herein, first‐principles calculations are employed to construct the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH, exploring its electronic properties, contact characteristics, and the impact of electric gating. The HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH is predicted to be structurally, thermally, and mechanically stable. The HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH leads to a reduction in the bandgap compared to the constituent components, potentially enhancing optical absorption. Furthermore, the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ heterostructure forms the type‐II band alignment, localizing electrons and holes predominantly in the HfS2${\rm HfS}_2$ and MoS2${\rm MoS}_2$ layers, respectively. Such type‐II HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ heterostructure makes it promising candidate for the optoelectronic devices, benefiting from the spatial separation of photogenerated electron‐hole pairs. Notably, the electronic properties and contact characteristics of the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH are controllable under electric gating. The negative electric gating facilitates to a transformation from type‐II to type‐I band alignment, while the positive electric field induces a shift from semiconductor to metal in the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH. This findings can provide valuable insights into the fundamental aspects that contribute to the exceptional performance observed in HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH toward high‐performance multifunctional devices. [ABSTRACT FROM AUTHOR]

The functionality of electronic and optoelectronic devices relying on two‐dimensional (2D) materials can be substantially influenced by the characteristics of their electrical contacts. Herein, a metal–semiconductor electrical contact between metallic NbS2 and semiconducting MoSe2 monolayer is constructed using first‐principles calculations. The electronic properties and contact characteristics of the NbS2/MoSe2 heterostructure as well as the effects of electric fields and in‐plane strains are also explored. These results indicate that the NbS2/MoSe2 heterostructure exhibits the p$p$‐type Schottky contact (ShC) with low Schottky barriers and possesses low contact resistance of the tunneling barrier. Furthermore, the electronic properties and contact characteristics of the NbS2/MoSe2 heterostructure can be fine‐tuned through the application of in‐plane strains and electric fields. The electric fields give rise to the transformation from p$p$‐type to n$n$‐type ShC as well as the conversion from ShC to Ohmic contact (OhC) in the NbS2/MoSe2 heterostructure. Similarly, in‐plane strains play a role in direct‐to‐indirect band gap transitions and further contribute to the conversion from ShC to OhC in the NbS2/MoSe2 heterostructure. These findings offer valuable theoretical insights that can guide the practical utilization of the NbS2/MoSe2 vdW‐MSH in the development of next‐generation electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Recently, by forming a P‐rich P–S system, the P3S monolayer has been predicted to have good resistance to air oxidation, large band gap, high absorption, and superior mobility. Inheriting this prediction, a series of ternary Janus P6XY (X/Y = S, Se, and Te; X ≠ Y) monolayers based on P3X nanosheet are designed and studied. The structures of P6XY monolayers are confirmed to be stable based on the evaluation of calculated results for phonon spectra, ab initio molecular dynamic simulations. It is also found that P6XY compounds possess anisotropic mechanical characteristics. All Janus structures are indirect semiconductors with large energy gaps varying from 2.12 to 2.60 eV calculated by the hybrid functional. Besides, biaxial strain significantly affects the electronic properties of the P6XY monolayers. In particular, the biaxial strains can induce a transition from indirect to direct bandgap in all three P6XY structures. The carrier mobility in the three proposed structures exhibits directional anisotropy and high electron mobility value, up to 1.27 × 103 cm2 V−1 s−1, which are suitable for applications in high‐performance and direction‐dependent nanoelectronic devices. [ABSTRACT FROM AUTHOR]

Since the recent successful experimental synthesis of MoSi2N4 [Science, 369 (2020), 670], the "MA2Z4 family" has been of particular interest to the scientists in the field of materials science due to its outstanding physical properties. In this paper, the first‐principles calculations are performed to study the structural, elastic, and electronic properties of novel two‐dimensional (2D) Janus MSiGeN4 monolayers (M = Ti, Zr, Hf). The calculations of phonon spectra indicate that monolayers MSiGeN4 are dynamically stable and can be experimentally synthesized. The obtained Young's modulus and Poisson's ratio of the Janus structures MSiGeN4 are much larger than that of other binary 2D materials and meet the mechanical stability criteria suggested by Born and Huang. In the calculations using either PBE or HSE06 functionals, the Janus MSiGeN4 structures exhibit indirect semiconductor characteristics with larger band gaps than that of similar septuple‐atomic‐layer materials, such as MoSiGeN4 and WSiGeN4. In addition, the influences of biaxial strain and external electric field on the electronic structure of MSiGeN4 are investigated. It is found that the biaxial strain tunes the electronic characteristics more significantly than the external electric field. The obtained results can provide insights into novel Janus monolayers with potential applications in electronic devices. [ABSTRACT FROM AUTHOR]

Sjogren's syndrome (SS) is a chronic, progressive autoimmune disease featuring both organ-specific and systemic manifestations, the most frequent being dry mouth and dry eyes resulting from lymphocytic infiltration into the salivary and lacrimal glands. Like the related autoimmune disease systemic lupus erythematosus (SLE), SS patients and mouse models display accumulation of apoptotic cells and a Type I interferon (IFN) signature. Receptor tyrosine kinases (RTKs) of the Tyro3, Axl, and Mer (TAM) family are present on the surface of macrophages and dendritic cells and participate in phagocytosis of apoptotic cells (efferocytosis) and inhibition of Type I IFN signaling. This review examines the relationship between TAM receptor dysfunction and SS and explores the potential contributions of TAM defects on macrophages to SS development. [ABSTRACT FROM AUTHOR]

Hepatitis C virus (HCV) is a pandemic disease affecting an estimated 180 million individuals worldwide and infecting each year another ~3-4 million people making HCV a global public health issue. HCV is the main cause for chronic hepatitis, cirrhosis, and hepatocellular carcinoma. In the United States, HCV-related chronic liver disease is a leading cause of liver transplantation. Despite significant improvements in antiviral drugs, only ∼50% of treated patients with HCV have viral clearance after treatment. Showing unique species specificity, HCV has a narrow range of potential hosts infecting only chimpanzees and humans. For decades, the chimpanzee model has been the only and instrumental primate for studying HCV infection; however, availability, economic, and ethical issues make the chimpanzee an unsuitable animal model today. Thus, significant research has been devoted to explore different models that are suitable in studying the biology of the virus and application in the clinical research for developing efficient and tolerable treatments for patients. This review focuses on experimental models that have been developed to date and their findings related to HCV. [ABSTRACT FROM AUTHOR]

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a multifaceted range of symptoms affecting almost every organ system. The prototypical pathology of SLE involves the production of antinuclear antibodies and the deposition of immune complexes in basement membranes throughout the body where they induce inflammatory responses. The genetic and environmental etiologies of this process are being intensively sought, and recently, TH17 cells have been implicated in the pathogenesis of SLE. TH17 cells are CD4+ memory T cells that behave as both helper and effector cell populations functioning through their signature IL-17 cytokines. Their differentiation is distinct to either the TH1 or TH2 cell lineage, but strongly influences development of adaptive responses, including autoimmunity. This paper details the biological functions and regulation of TH17 cells, followed by an update of their expanding role in SLE. [ABSTRACT FROM AUTHOR]

Sjögren's syndrome (SjS) is a complex chronic autoimmune disease of unknown etiology which primarily targets the exocrine glands, resulting in eventual loss of secretory function. The disease can present as either primary SjS or secondary SjS, the latter of which occurs concomitantly with another autoimmune disease such as rheumatoid arthritis, systemic lupus erythematosus, scleroderma, or primary biliary cirrhosis. Current advancements in therapeutic prevention and treatment for SjS are impeded by lack of understanding in the pathophysiological and clinical progression of the disease. Development of appropriate mouse models for both primary and secondary SjS is needed in order to advance knowledge of this disease. This paper details important features, advantages, and pitfalls of current animal models of SjS, including spontaneous, transgenic, knockout, immunization, and transplantation chimera mouse models, and emphasizes the need for a better model in representing the human SjS phenotype. [ABSTRACT FROM AUTHOR]

The article investigates the role of Th17/interleukin-23 (IL-23) system in Sjögren's syndrome (SS). C57BL/6.NOD-Aec1Aec2 mice were used in the experiment. Results showed that the Th17/IL-23 system is up-regulated in the mice model and SS patients. It cautions that a connection between up-regulated IL-17/IL-23 expression and specific SS clinical manifestations has not been identified yet.