Advancing teeth whitening efficacy via dual-phototherapeutic strategy incorporating molybdenum disulfide embedded in carrageenan hydrogel for dental healthcare.

Teeth discoloration poses a widespread challenge in dental health across various regions. Conventional teeth whitening methods often result in enamel deterioration and soft tissue harm due to the utilization of incompatible whitening agents and continuous intense light exposure. Here, we propose an effective phototherapy technique for teeth whitening, employing pathways of energy transition through intersystem crossing. The integration of MoS2 nanosheets into carrageenan gel (MoS2 NSs@Carr) facilitates both photothermal-hyperthermia and the generation of reactive oxygen species (ROS) through photocatalytic processes. The efficacy of ROS generation by the phototherapeutic MoS2 NSs@Carr on teeth whitening in the scenario. This approach ensures comprehensive teeth whitening by eliminating deep-seated stains on the teeth while preserving structural integrity and avoiding any tissue toxicity. This research highlights the efficacy of the phototherapeutic MoS2 NSs@Carr for dental whitening and underscores the potential of exploring nanostructures based on MoS2 NSs for managing dental healthcare issue.

Planar-/Curvilinear-Bioprinted Tri-Cell-Laden Hydrogel for Healing Irregular Chronic Wounds.

Chronic cutaneous wounds from tissue trauma or extensive burns can impair skin barrier function and cause severe infection. Fabrication of a customizable tissue-engineered skin is a promising strategy for regeneration of uneven wounds. Herein, a planar-/curvilinear-bioprintable hydrogel is developed to produce tissue-engineered skin and evaluated in rat models of chronic and irregular wounds. The hydrogel is composed of biodegradable polyurethane (PU) and gelatin. The hydrogel laden with cells displays good 3D printability and structure stability. The circular wounds of normal and diabetes mellitus (DM) rats treated with planar-printed tri-cell-laden (fibroblasts, keratinocytes, and endothelial progenitor cells (EPCs)) hydrogel demonstrate full reepithelization and dermal repair as well as large amounts of neovascularization and collagen production after 28 days. Furthermore, the curvilinear module is fabricated based on the corresponding wound topography for curvilinear-bioprinting of the irregular tissue-engineered skin. The large and irregular rat skin wounds treated with curvilinear-printed tri-cell-laden hydrogel demonstrate full repair after 28 days. This planar-/curvilinear-bioprintable tri-cell-laden hydrogel shows great potential for customized biofabrication in skin tissue engineering.

Metabolic protein phosphoglycerate kinase 1 confers lung cancer migration by directly binding HIV Tat specific factor 1.

Phosphoglycerate kinase (PGK) is involved in glycolytic and various metabolic events. Dysfunction of PGK may induce metabolic reprogramming and the Warburg effect. In this study, we demonstrated that PGK1, but not PGK2, may play a key role in tumorigenesis and is associated with metastasis. We observed an inverse correlation between PGK1 and the survival rate in several clinical cohorts through bioinformatics statistical and immunohistochemical staining analyses. Surprisingly, we found that PGK1 was significantly increased in adenocarcinoma compared with other subtypes. Thus, we established a PGK1-based proteomics dataset by a pull-down assay. We further investigated HIV-1 Tat Specific Factor 1 (HTATSF1), a potential binding partner, through protein-protein interactions. Then, we confirmed that PGK1 indeed bound to HTATSF1 by two-way immunoprecipitation experiments. In addition, we generated several mutant clones of PGK1 through site-directed mutagenesis, including mutagenesis of the N-terminal region, the enzyme catalytic domain, and the C-terminal region. We observed that even though the phosphoglycerate kinase activity had been inhibited, the migration ability induced by PGK1 was maintained. Moreover, our immunofluorescence staining also indicated the translocation of PGK1 from the cytoplasm to the nucleus and its colocalization with HTATSF1. From the results presented in this study, we propose a novel model in which the PGK1 binds to HTATSF1 and exerts functional control of cancer metastasis. In addition, we also showed a nonenzymatic function of PGK1.

Novel Virulence Role of Pneumococcal NanA in Host Inflammation and Cell Death Through the Activation of Inflammasome and the Caspase Pathway.

Streptococcus pneumoniae is one of most deadly Gram-positive bacterium that causes significant mortality and morbidity worldwide. Intense inflammation and cytotoxicity is a hallmark of invasive pneumococcal disease. Pneumococcal NanA has been shown to exaggerate the production of inflammatory cytokines via unmasking of inhibitory Siglec-5 from its sialyl cis-ligands. To further investigate the mechanistic role of NanA and Siglec-5 in pneumococccal diseases, we systemically analyzed genes and signaling pathways differentially regulated in macrophages infected with wild type and NanA-deficient pneumococcus. We found that NanA-mediated desialylation impairs the Siglec-5-TLR-2 interaction and reduces the recruitment of phosphatase SHP-1 to Siglec-5. This dysregulated crosstalk between TLR-2 and inhibitory Siglec-5 exaggerated multiple inflammatory and death signaling pathways and consequently caused excessive inflammation and cytotoxicity in the infected macrophage. Collectively, our results reveal a novel virulence role of NanA in pneumococcal pathogenesis and suggest that targeting NanA activity may ameliorate the pneumococcus-mediated inflammation and cytotoxicity in severe invasive pneumococcal diseases.

Tunable Moiré Superlattice of Artificially Twisted Monolayers.

Twisting between two stacked monolayers modulates periodic potentials and forms the Moiré electronic superlattices, which offers an additional degree of freedom to alter material property. Considerable unique observations, including unconventional superconductivity, coupled spin-valley states, and quantized interlayer excitons are correlated to the electronic superlattices but further study requires reliable routes to study the Moiré in real space. Scanning tunneling microscopy (STM) is ideal to precisely probe the Moiré superlattice and correlate coupled parameters among local electronic structures, strains, defects, and band alignment at atomic scale. Here, a clean route is developed to construct twisted lattices using synthesized monolayers for fundamental studies. Diverse Moiré superlattices are predicted and successfully observed with STM at room temperature. Electrical tuning of the Moiré superlattice is achieved with stacked TMD on graphite.

Photoresponse of an Organic Semiconductor/Two-Dimensional Transition Metal Dichalcogenide Heterojunction.

We study the optoelectronic properties of a type-II heterojunction (HJ) comprising a monolayer of the transition metal dichalcogenide (TMDC), WS2, and a thin film of the organic semiconductor, 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA). Both theoretical and experimental investigations of the HJ indicate that Frenkel states in the organic layer and two-dimensional Wannier-Mott states in the TMDC dissociate to form hybrid charge transfer excitons at the interface that subsequently dissociate into free charges that are collected at opposing electrodes. A photodiode employing the HJ achieves a peak external quantum efficiency of 1.8 ± 0.2% at a wavelength of 430 ± 10 nm, corresponding to an internal quantum efficiency (IQE) as high as 11 ± 1% in these ultrathin devices. The photoluminescence spectra of PTCDA and PTCDA/WS2 thin films show that excitons in the WS2 have a quenching rate that is approximately seven times higher than in PTCDA. This difference leads to strong wavelength dependence in IQE.

Synthesis of lateral heterostructures of semiconducting atomic layers.

Atomically thin heterostructures of transition-metal dichalcogenides (TMDs) with various geometrical and energy band alignments are the key materials for next generation flexible nanoelectronics. The individual TMD monolayers can be adjoined laterally to construct in-plane heterostructures, which are difficult to reach with the laborious pick-up-and-transfer method of the exfoliated flakes. The ability to produce copious amounts of high quality layered heterostructures on diverse surfaces is highly desirable but it has remained a challenging issue. Here, we have achieved a direct synthesis of lateral heterostructures of monolayer TMDs: MoS(2)-WS(2) and MoSe(2)-WSe(2). The synthesis was performed using ambient-pressure chemical vapor deposition (CVD) with aromatic molecules as seeding promoters. We discuss possible growth behaviors, and we examine the symmetry and the interface of these heterostructures using second-harmonic generation and atomic-resolution scanning TEM. We found that the one-dimensinal (1D) interface of the lateral heterostructures picks the zigzag direction of the lattice instead of the armchair direction. Our method offers a controllable synthesis to obtain high-quality in-plane heterostructures of TMD atomic layers with 1D interface geometry.