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Non-centrosymmetric (NCS) structure is an indispensable prerequisite for second-order nonlinear optical (NLO) material. Currently, the mainstream approach for designing new NCS structures still relies on chemical substitution, necessitating an urgent infusion of fresh ideas. In this work, two isomorphic sulfides AeMn6Ga6S16 (Ae = Ca, 1; Sr, 2) are afforded by modifying the skeleton of centrosymmetric (CS) Mn2Ga2S5via introducing strong electropositive alkaline-earth cations. Concretely, the incorporation of Ca2+/Sr2+ cations allows the elementary [MnGaS9]∞ chains to reconfigure into bumpy [MnS6]-[GaS4] layers in a new engagement manner, thus enabling the conversion from CS to NCS structure. Such modifications cause not only strong second-harmonic generation (SHG) responses (∼1.5 × benchmark AgGaS2 @1,700 nm), but also significantly feasible bandgaps (2.60–2.64 eV) compared to the sulfide Mn2Ga2S5 (1.36 eV), which ultimately facilitate ultrahigh laser-induced damage thresholds (4.4–6.6 × AgGaS2 @1,064 nm for compounds 1 and 2). The present study offers an ingenious approach for the transformation of CS to NCS structure. [ABSTRACT FROM AUTHOR]

The traditional fermentation process of soy sauce employs a hyperhaline model and has a long fermentation period. A hyperhaline model can improve fermentation speed, but easily leads to the contamination of miscellaneous bacteria and fermentation failure. In this study, after the conventional koji and moromi fermentation, the fermentation broth was pasteurized and diluted, and then inoculated with three selected microorganisms including Corynebacterium glutamicum, Corynebacterium ammoniagenes, and Lactiplantibacillus plantarum for secondary fermentation. During this ten-day fermentation, the pH, free amino acids, organic acids, nucleotide acids, fatty acids, and volatile compounds were analyzed. The fermentation group inoculated with C. glutamicum accumulated the high content of amino acid nitrogen of 0.92 g/100 mL and glutamic acid of 509.4 mg/100 mL. The C. ammoniagenes group and L. plantarum group were rich in nucleotide and organic acid, respectively. The fermentation group inoculated with three microorganisms exhibited the best sensory attributes, showing the potential to develop a suitable fermentation method. The brewing speed of the proposed process in this study was faster than that of the traditional method, and the umami substances could be significantly accumulated in this low-salt fermented model (7% w/v NaCl). This study provides a reference for the low-salt and rapid fermentation of seasoning. [ABSTRACT FROM AUTHOR]

Scintillators are essential in converting ionizing X‐rays and γ‐rays into visible light, with applications in medical diagnosis, security inspection, and non‐invasive detection. However, current scintillating materials exhibit unclear structure–function relationships. The performance of scintillators is intricately linked to their electronic band structure, particularly the intrinsic properties of excited states. Therefore, investigating the structural factors affecting scintillation performance is crucial for developing new scintillators. Therefore, Ba‐SMOF 1 ([Ba2(PyTS)(CH3OH)2(H2O)4]n) is synthesized using a pyrene‐based organic motif and metal Ba(II) ions, where PyTS4− refers to pyrene‐1,3,6,8‐tetrasulfonate. For the first time, the excited state of a pyrene‐based X‐ray scintillating metal–organic framework (MOF) is determined through comprehensive all‐electron excitation studies, including in situ experimental electron density and wave‐function analysis. The electron density maps exhibit a continuous overlap, attributed to the associative exciton behaviors among the closely packed PyTS4− linkers. These linkers are identified as the sources of both static and dynamic excimer emissions. The electron density studies reveal the role of excimers in pyrene‐based luminophores, highlighting that interchromophoric interactions are key to enhancing the performance of scintillating MOFs. This discovery opens new avenues for the practical application of scintillating MOFs. [ABSTRACT FROM AUTHOR]

Nonlinear optical (NLO) materials are of immense scientific and technological importance. However, debate has long prevailed theoretically regarding the structural origin of the second harmonic generation (SHG) effect. In this work, the experimental electron density (ED) of controversial β‐BaB2O4 (BBO) is studied by high‐resolution X‐ray diffraction, indicating that the [B3O6]3− motif dominates two large non‐zero SHG tensors (d222 and d311) while Ba atoms contribute mostly to the smallest one (d333), and the atomic SHG contributions of terminal O atoms in [B3O6]3− motifs are much larger than those of B and bridged O atoms, clarifying the disputes on its NLO response mechanism. Besides, the contraction of inner electron shells (5s25p6) of the Ba atom and partial covalent behavior of the Ba─O interaction are first observed experimentally. Furthermore, the SHG coefficients of BBO derived from experimental ED are in excellent agreement with those from bulk crystals, providing a high‐efficient and low‐cost method of screening high‐performance NLO materials with just an easy‐to‐obtain tiny crystal. [ABSTRACT FROM AUTHOR]

As a part of Alzheimer’s disease (AD) development the mammalian target of rapamycin (mTOR) has been reported to play a crucial role in regulating cognition and can be used as a neuronal marker. Neuro-inflammation is also a cause of the pathophysiological process in AD. Thus, we examined the protein expression levels of mTOR and its downstream pathways as well as pro-inflammatory cytokines (PICs) in the brain of AD rats. We further examined the effects of blocking mTOR on PICs, namely IL-1β, IL-6 and TNF-α. Our results showed that the protein expression of p-mTOR, mTOR-mediated phosphorylation of 4E-binding protein 4 (4E-BP1) and p70 ribosomal S6 protein kinase 1 (S6K1) pathways were amplified in the hippocampus of AD rats compared with controls. Blocking mTOR by using rapamycin selectively enhanced activities of IL-6 and TNF-α signaling pathways, which was accompanied with an increase of Caspase-3, indicating cellular apoptosis and worsened learning performance. In conclusion, our data for the first time revealed specific signaling pathways engaged in the development of AD, including a regulatory role by the activation of mTOR in PIC mechanisms. Stimulation of mTOR is likely to play a beneficial role in modulating neurological deficits in AD.Targeting one or more of these signaling molecules may present with new opportunities for treatment and clinical management of AD

Ulinastatin [urinary trypsin inhibitor (UTI)] plays an important role in the protection of organs against ischemic injury during severe inflammation. The purposes of this study were to examine the effects of UTI on the levels of pro-inflammatory cytokines (PICs) and protein expression of PIC receptors in the neocortex and hippocampus CA1 region of rats after transient global ischemia induced via cardiac arrest (CA). Specifcally, interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were analyzed. CA was induced by asphyxia followed by cardiopulmonary resuscitation in rats. ELISA and western blot analysis were employed to determine PICs and their receptors in the neocortex and hippocampus. Our results show that IL-1β, IL-6 and TNF-α were significantly elevated in the neocortex and hippocampal CA1 field after CA. This was accompanied with an increase in PIC receptors, namely IL-1R, IL-6R and TNFR1. Systemic injection of UTI attenuated the amplification of PIC signal pathways in these brain regions. UTI also improved the modified Neurological Severity Score and brain tissue edema in CA rats. Notably, UTI resulted in an increase in survival of CA rats as compared to CA rats without treatment. In conclusion, UTI plays a beneficial role in modulating transient global ischemia induced by CA by altering PIC signal mechanisms, but further studies are needed to draw more firm conclusions.

In contrast to anionic group theory of nonlinear optical (NLO) materials that second‐harmonic generation (SHG) responses mainly originate from anionic groups, structural regulation on the cationic groups of salt‐inclusion chalcogenides (SICs) is performed to make them also contribute to the NLO effects. Herein, the stereochemically active lone–electron‐pair Pb2+ cation is first introduced to the cationic groups of NLO SICs, and the resultant [K2PbX][Ga7S12] (X = Cl, Br, I) are isolated via solid‐state method. The features of their three‐dimensional structures comprise highly oriented [Ga7S12]3− and [K2PbX]3+ frameworks derived from AgGaS2, which display the largest phase‐matching SHG intensities (2.5−2.7 × AgGaS2 @1800 nm) among all SICs. Concurrently, three compounds manifest band gap values of 2.54, 2.49, and 2.41 eV (exceeding the criterion of 2.33 eV), which can avoid two‐photon absorption under the fundamental laser of 1064 nm, along with the relatively low anisotropy of thermal expansion coefficients, leading to improved laser‐induced damage thresholds (LIDTs) values of 2.3, 3.8, and 4.0 times that of AgGaS2. In addition, the density of states and SHG coefficient calculations demonstrate that the Pb2+ cations narrow the band gaps and benefit SHG responses. [ABSTRACT FROM AUTHOR]

A crystal structure with a diamond-like anionic framework belongs to a non-centrosymmetric macrostructure due to the aligned arrangement of tetrahedral units, meeting the premise of second-order nonlinear optical (NLO) materials. Herein, two new Hg-based sulphides, namely RbHg4Ga5S12 (1) and CsHg4Ga5S12 (2), which are isostructural and crystallise in the trigonal space group R3, are successfully isolated in sealed silica tubes by a solid-state reaction. The features of their three-dimensional open honeycomb frameworks are attributed to the parallel alignment of tetrahedral MS4 (M is disordered by 0.444 Hg and 0.555 Ga) building motifs, accompanied by Rb+ (or Cs+) reseating in the cavities. Notably, although the band gap values of 1 and 2 are 2.30 and 2.36 eV, separately, their thermal expansion anisotropies (0.15 and 0.41, respectively) are favourable for achieving laser-induced damage thresholds (5.6 and 5.8 times that of AgGaS2 for 1 and 2, respectively). In addition, the strong polarisability of tetrahedral MS4 building motifs in the diamond-like anionic structures is responsible for the promising second-harmonic generation (SHG) intensities (1.1 and 1.8 times that of AgGaS2 for 1 and 2, respectively) in the particle size range of 50–75 μm with non-phase-matchable behaviour at 1910 nm. Furthermore, theoretical investigation elaborates that electron transitions in compounds 1 and 2 mainly occur from valence band S-3p to conduction band Hg-6s and Ga-4s states, demonstrating that the linear and nonlinear optical properties originate primarily from the synergy of tetrahedral MS4 units. [ABSTRACT FROM AUTHOR]

A quaternary metal chalcogenide, namely K2CdGe3S8 (I), is obtained through a high-temperature solid-state approach. Compound I crystallizes with the non-centrosymmetric space group P212121. It features a 2D layer structure with [CdGe3S8] layers consisting of tetrahedral GeS4 and CdS4 units, and counter K+ embedded between the layers. The compound exhibits a powder second-harmonic generation (SHG) response of ~0.1 times that of KH2PO4 (KDP) with phase-matchable character at the laser wavelength of 1064 nm. Remarkably, it has a wide band gap (3.20 eV), which corresponds to a favorable high laser-induced damage threshold of 6.7 times that of AgGaS2. In addition, the calculated birefringence (Δn) is 0.039 at the wavelength of 1064 nm, which satisfies the Δn criteria for a promising infrared NLO material. [ABSTRACT FROM AUTHOR]

Lung cancer is the leading cause of cancer death worldwide, of which lung adenocarcinoma (LUAD) is the most common subtype. Metastasis is the major cause of poor prognosis and mortality for lung cancer patients, which urgently needs great efforts to be further explored. Herein, glutathione peroxidase 8 (GPX8) was identified as a novel potential pro‐metastatic gene in LUAD metastatic mice models from GEO database. GPX8 was highly expressed in tumor tissues, predicting poor prognosis in LUAD patients. Knockdown of GPX8 inhibited LUAD metastasis in vitro and in vivo, while it did not obviously affect tumor growth. Knockdown of GPX8 decreased the levels of p‐FAK and p‐Paxillin and disturbed the distribution of focal adhesion. Furthermore, GPX8 was overexpressed in cancer‐associated fibroblast (CAF) and associated with CAF infiltration in tumor microenvironment of lung cancer. GPX8 silence on fibroblasts suppressed lung cancer cell migration in the coculture system. BRD2 and RRD4 were the potential transcriptionally regulators for GPX8. Bromodomain extra‐terminal inhibitor JQ1 downregulated GPX8 expression and suppressed lung cancer cell migration. Our findings indicate that highly expressed GPX8 in lung cancer cells and fibroblasts functions as a pro‐metastatic factor in lung cancer. JQ1 is identified as a potential inhibitor against GPX8‐mediated lung cancer metastasis. [ABSTRACT FROM AUTHOR]