Boronic Acid-Decorated Carbon Dot-Based Semiselective Multichannel Sensor Array for Cytokine Discrimination and Oral Cancer Diagnosis.

Cytokines are essential components of the immune system and are recognized as significant biomarkers. However, detection of a single cytokine is not precise and reliable enough to satisfy the requirements for diagnosis. Herein, we developed a pattern recognition-based method for the multiplexed sensing of cytokines, which involves three-color-emitting boronic acid-decorated carbon dots (BCDs) and arginine-modified titanium carbide (Ti3C2 MXenes) as the sensor array. Initially, the fluorescence signals of the three BCDs were quenched by Ti3C2 MXenes. In the presence of cytokines, the fluorescence intensity of the BCDs was restored or further quenched by different cytokines. The fluorescence response occurs in two steps: first, boronic acid interacts with cis-diol functional groups of cytokines, and second, arginine headgroup selectively interacts with glycans. By exploiting the different competing binding of the BCDs and the cytokines toward Ti3C2 MXenes, seven cytokines and their mixtures can be effectively discriminated at a concentration of 20 ng mL-1. Furthermore, our sensor array demonstrated an excellent performance in classifying human oral cancer saliva samples from healthy individuals with clinically relevant specificity. The noninvasive method offers a rapid approach to cytokine analysis, benefiting early and timely clinical diagnosis and treatment.

Two-Photon Cellular and Intravital Imaging of Hypochlorous Acid by Fluorescent Probes That Exhibit a Synergistic Excited-State Intramolecular Proton Transfer-Intramolecular Charge Transfer Mechanism Enabling Near-Infrared Emission with a Large Stokes Shift.

To develop highly effective molecular tools for intravital imaging of hypochlorous acid (HOCl), in this study, we initially designed two-photon hybrid fluorophores, SDP and P-SDP, by conjugating the classical dye 2-(2'-hydroxyphenyl)benzothiazole with the two-photon hydroxylphenyl-butadienylpyridinium fluorophore. The designed fluorophores exhibit a synergistic interaction between excited-state intramolecular proton transfer and intramolecular charge transfer mechanisms, enabling near-infrared (NIR) emission and significant Stokes shifts. Subsequently, using these fluorophores, we developed two HOCl fluorescent probes, SDP-SN and P-SDP-SN, by further incorporating N,N-dimethylthiocarbamate as a specific recognition group for HOCl. Toward HOCl, both SDP-SN and P-SDP-SN demonstrate an ultrafast response (less than 3 s), NIR emission at wavelengths of 714 and 682 nm, and remarkable Stokes shifts of 303 and 271 nm, respectively. Leveraging these advantages in conjunction with their ability to cross the blood-brain barrier, the probes find successful application in two-photon cellular and intravital imaging of HOCl. This includes visualizing endogenous generation of HOCl in cellular models related to inflammation, hyperglycemia, and ferroptosis, as well as mapping in vivo generation of HOCl within the brain and abdominal cavity using a murine model of systemic inflammation.

A new chromosome-scale genome of wild Brassica oleracea provides insights into the domestication of Brassica crops.

The cultivated diploid Brassica oleracea is an important vegetable crop, but the genetic basis of its domestication remains largely unclear in the absence of high-quality reference genomes of wild B. oleracea. Here, we report the first chromosome-level assembly of the wild Brassica oleracea L. W03 genome (total genome size, 630.7 Mb; scaffold N50, 64.6 Mb). Using the newly assembled W03 genome, we constructed a gene-based B. oleracea pangenome and identified 29 744 core genes, 23 306 dispensable genes, and 1896 private genes. We re-sequenced 53 accessions, representing six potential wild B. oleracea progenitor species. The results of the population genomic analysis showed that the wild B. oleracea populations had the highest level of diversity and represents the most closely related population to modern-day horticultural B. oleracea. In addition, the WUSCHEL gene was found to play a decisive role in domestication and to be involved in cauliflower and broccoli curd formation. We also illustrate the loss of disease-resistance genes during selection for domestication. Our results provide new insights into the domestication of B. oleracea and will facilitate the future genetic improvement of Brassica crops.

MicroRNA-505-3p mediates cell motility of epithelial ovarian cancer via suppressing PEAK1 expression.

MicroRNAs (miRNAs) are a class of small RNA genes with important roles in cancer biology regulation. There are considerable studies regarding the roles of microRNA-505-3p (miR-505-3p) in cancer development and progression, but the function of miR-505-3p in epithelial ovarian cancer (EOC) has not been fully clarified. Comparative analysis of miRNA expression data set was used to select differentially expressed miRNAs. Quantitative real-time polymerase chain reaction was applied to detect expression levels of RNAs, while western blot and immunofluorescence staining were performed to detect expression levels of proteins of interest. The motility of EOC cells was assessed by wound healing and transwell assays. The binding and regulating relationship between miRNA and its direct target gene was investigated by dual-luciferase assay. Our results show that miR-505-3p was upregulated in recurrent EOC, which significantly inhibits EOC cell motility via modulating cell epithelial-mesenchymal transition. Furthermore, our results indicated that PEAK1 expression was inhibited by direct binding of miR-505-3p into its 3'-URT in EOC cells. Importantly, knockdown of PEAK1 attenuated the effect of mi-505-3p inhibitor on EOC cell migration and invasion. In conclusion, our findings indicate that miRNA-505-3p inhibits EOC cell motility by targeting PEAK1.

A multi-slice attention fusion and multi-view personalized fusion lightweight network for Alzheimer's disease diagnosis.

OBJECTIVE: Alzheimer's disease (AD) is a type of neurological illness that significantly impacts individuals' daily lives. In the intelligent diagnosis of AD, 3D networks require larger computational resources and storage space for training the models, leading to increased model complexity and training time. On the other hand, 2D slices analysis may overlook the 3D structural information of MRI and can result in information loss. APPROACH: We propose a multi-slice attention fusion and multi-view personalized fusion lightweight network for automated AD diagnosis. It incorporates a multi-branch lightweight backbone to extract features from sagittal, axial, and coronal view of MRI, respectively. In addition, we introduce a novel multi-slice attention fusion module, which utilizes a combination of global and local channel attention mechanism to ensure consistent classification across multiple slices. Additionally, a multi-view personalized fusion module is tailored to assign appropriate weights to the three views, taking into account the varying significance of each view in achieving accurate classification results. To enhance the performance of the multi-view personalized fusion module, we utilize a label consistency loss to guide the model's learning process. This encourages the acquisition of more consistent and stable representations across all three views. MAIN RESULTS: The suggested strategy is efficient in lowering the number of parameters and FLOPs, with only 3.75M and 4.45G respectively, and accuracy improved by 10.5% to 14% in three tasks. Moreover, in the classification tasks of AD vs. CN, AD vs. MCI and MCI vs. CN, the accuracy of the proposed method is 95.63%, 86.88% and 85.00%, respectively, which is superior to the existing methods. CONCLUSIONS: The results show that the proposed approach not only excels in resource utilization, but also significantly outperforms the four comparison methods in terms of accuracy and sensitivity, particularly in detecting early-stage AD lesions. It can precisely capture and accurately identify subtle brain lesions, providing crucial technical support for early intervention and treatment.

Use of artificial intelligence algorithms to analyse systemic sclerosis-interstitial lung disease imaging features.

The use of artificial intelligence (AI) in high-resolution computed tomography (HRCT) for diagnosing systemic sclerosis-associated interstitial lung disease (SSc-ILD) is relatively limited. This study aimed to analyse lung HRCT images of patients with systemic sclerosis with interstitial lung disease (SSc-ILD) using artificial intelligence (AI), conduct correlation analysis with clinical manifestations and prognosis, and explore the features and prognosis of SSc-ILD. Overall, 72 lung HRCT images and clinical data of 58 patients with SSC-ILD were collected. ILD lesion type, location, and volume on HRCT images were identified and evaluated using AI. The imaging characteristics of diffuse SSC (dSSc)-ILD and limited SSc-ILD (lSSc-ILD) were statistically analysed. Furthermore, the correlations between lesion type, clinical indicators, and prognosis were investigated. dSSc and lSSc were more prevalent in patients with a disease duration of < 1 and ≥ 5 years, respectively. SSc-ILD mainly comprises non-specific interstitial pneumonia (NSIP), usual interstitial pneumonia (UIP), and unclassifiable idiopathic interstitial pneumonia. HRCT reveals various lesion types in the early stages of the disease, with an increase in the number of lesion types as the disease progresses. Lesions appearing as grid, ground-glass, and nodular shadows were dispersed throughout both lungs, while those appearing as consolidation shadows and honeycomb were distributed across the lungs. Ground-glass opacity lesion type was absent on HRCT images of patients with SSc-ILD and pulmonary hypertension. This study showed that AI can efficiently analyse imaging characteristics of SSc-ILD, demonstrating its potential to learn from complex images with high generalisation ability.

Design, synthesis and biological evaluation of aloperine derivatives as potential anticancer agents.

Modifications at different positions on the aloperine molecule were performed to improve its anticancer activity and develop anticancer drugs. The in vitro anticancer activities of 44 synthesized compounds were evaluated. The effect of modification positions on anticancer activity was discussed and a structure-activity relationship analysis was established. A novel series of compounds with modifications at the N12 position showed much higher cytotoxicity than aloperine. Among them, compound 22 displayed promising in vitro anticancer activity against PC9 cells with a median inhibitory concentration (IC50) of 1.43 µM. The mechanism studies indicated that compound 22 induced cell apoptosis and cell cycle arrest in PC9 cells. These results demonstrate the potential of aloperine thiourea derivatives in anticancer activity.

Targeted Protein Degradation Mediated by Genetically Engineered Lysosome-Targeting Exosomes.

Protein-degrading chimeras are superior drug modalities compared to traditional protein inhibitors because of their effective therapeutic performance. So far, various targeted protein degradation strategies, including proteolysis-targeting chimeras and lysosome-targeting chimeras, have emerged as essential technologies for tackling diseases caused by abnormal protein expression. Here, we report the development and application of lysosome-targeting exosomes (LYTEXs) for the selective degradation of membrane protein targets. LYTEXs are genetically engineered exosomes expressing multivalent single-chain fragment variables, simultaneously recognizing cell-surface lysosome-targeting and to-be-degraded protein. We show that by targeting the lysosome-directing asialoglycoprotein receptor, bispecific LYTEXs can induce lysosomal degradation of membrane-associated therapeutic targets. This strategy provides a generalizable, easy-to-prepare platform for modulating surface protein expression, with the advantage of therapeutic delivery.

Proteomics analysis of enzyme systems and pathway changes during the moromi fermentation of soy sauce mash.

BACKGROUND: During the brewing of soy sauce, the conversion of multiple substances is driven by various microorganisms and their secreted enzyme systems. Soy sauce mash is an important source of enzyme systems during moromi fermentation, but the changes of enzyme systems in soy sauce mash during moromi fermentation are poorly understood. In order to explore the predominant enzyme systems existing during moromi fermentation and to explain the characteristics of the enzyme system changes, an enzymatic activities assay and 4D-label-free proteomics analysis were conducted on soy sauce mash at different stages of fermentation. RESULTS: The activities of hydrolytic enzymes in soy sauce mash decreased continuously throughout the fermentation process, while most of the characteristic physicochemical substances in soy sauce mash supernatant had already accumulated at the early stage of fermentation. Four hydrolytic enzymes were found to be positively correlated with important physicochemical indexes by principal component analysis and Pearson correlation analysis. The proteomics analysis revealed three highly upregulated enzymes and two enzymes that were present in important metabolic pathways throughout the fermentation process. Furthermore, it was found that Aspergillus oryzae was able to accumulate various nutrients in the soy sauce mash by downregulating most of its metabolic pathways. CONCLUSION: Enzymes present with excellent properties during the moromi fermentation period could be obtained from these results. Meanwhile, the characterization of the metabolic pathways of microorganisms during the moromi fermentation period was revealed. The results provide a basis for more scientific and purposeful improvement of moromi fermentation in the future. © 2024 Society of Chemical Industry.

Comparative analysis of microbial composition and functional characteristics in dental plaque and saliva of oral cancer patients.

BACKGROUND: The oral cavity is home to various ecological niches, each with its own unique microbial composition. Understanding the microbial communities and gene composition in different ecological niches within the oral cavity of oral cancer (OC) patients is crucial for determining how these microbial populations contribute to disease progression. METHODS: In this study, saliva and dental plaque samples were collected from patients with OC. Metagenomic sequencing was employed to analyze the microbial community classification and functional composition of the different sample groups. RESULTS: The results of the study revealed significant differences in both the function and classification of microbial communities between saliva and dental plaque samples. The diversity of microbial species in saliva was found to be higher compared to  that in plaque samples. Notably, Actinobacteria were enriched in the dental plaque of OC patients. Furthermore, the study identified several inter-group differential marker species, including Prevotella intermedia, Haemophilus parahaemolyticus, Actinomyces radius, Corynebacterium matruchitii, and Veillonella atypica. Additionally, 1,353 differential genes were annotated into 23 functional pathways. Interestingly, a significant correlation was observed between differentially labeled species and Herpes simplex virus 1 (HSV-1) infection, which may be related to the occurrence and development of cancer. CONCLUSIONS: Significant differences in the microbial and genetic composition of saliva and dental plaque samples were observed in OC patients. Furthermore, pathogenic bacteria associated with oral diseases were predominantly enriched in saliva. The identification of inter-group differential biomarkers and pathways provide insights into the relationship between oral microbiota and the occurrence and development of OC.

In Situ Chiral Template Approach to Synthesize Homochiral Lead Iodides for Second-Harmonic Generation.

Homochiral halide perovskites have gained increasing attention because of their fascinating optoelectronic properties and prospective applications in laser technologies. However, the limited choice of chiral organic templates severely restricts their structural diversity and second-harmonic generation (SHG) effects. Here, we present an in situ chiral template approach for the synthesis of one-dimensional (1D) homochiral lead iodides. A chiral imine (L-ipp) template was generated in situ by reacting L-proline (L-pro) and acetone under ambient conditions. Notably, L-ipp can cooperate with L-pro to direct the formation of a homochiral lead iodide with dual chiral templates, which is unprecedented in crystalline metal halides. The homochiral lead iodide containing both L-ipp and L-pro shows a strong SHG response of 8.0 times that of KH2 PO4 (8.0×KDP). The SHG efficiency is one of the largest values reported to date for any homochiral lead halides under 1064 nm laser irradiation. A comparative study shows that homochiral 1D lead iodides containing either L-ipp or L-pro exhibit relatively weak SHG responses (≤1.0×KDP). This work demonstrates the advantage of using two different chiral templates over a single chiral template in enhancing the SHG responses of halide materials.

Bioinformatic and functional analysis of OsDHN2 under cadmium stress.

As a toxic heavy metal, cadmium (Cd) is one of the principal pollutants influencing rice productivity and food security. Despite several studies, the underlying mechanism of Cd response in plants remains largely unclear. Dehydrins are part of the late embryogenesis abundant (LEA) family which protect plants against abiotic stresses. In this study, a Cd-responsive LEA gene, OsDHN2, was functionally characterized. The chromosome localization results indicated that OsDHN2 was located on chromosome 2 of rice. Meanwhile, cis-acting elements, such as MBS (MYB binding site involved in drought-inducibility), ARE (anaerobic induction), and ABRE (abscisic acid), were present in the OsDHN2 promoter region. Expression pattern analysis also showed that OsDHN2 expression was induced in both roots and shoots under Cd stress. Overexpression of OsDHN2 improved Cd tolerance and reduced Cd concentration in yeast. Moreover, increased expression levels of SOD1, CTA1, GSH1, or CTT1 were found in transgenic yeast under Cd stress, suggesting the increased antioxidant enzymatic activities. These results suggested that OsDHN2 is a Cd-responsive gene that has the potential to improve resistance to Cd in rice.

RGS5 augments astrocyte activation and facilitates neuroinflammation via TNF signaling.

Astrocytes contribute to chronic neuroinflammation in a variety of neurodegenerative diseases, including Parkinson's disease (PD), the most common movement disorder. However, the precise role of astrocytes in neuroinflammation remains incompletely understood. Herein, we show that regulator of G-protein signaling 5 (RGS5) promotes neurodegenerative process through augmenting astrocytic tumor necrosis factor receptor (TNFR) signaling. We found that selective ablation of Rgs5 in astrocytes caused an inhibition in the production of cytokines resulting in mitigated neuroinflammatory response and neuronal survival in animal models of PD, whereas overexpression of Rgs5 had the opposite effects. Mechanistically, RGS5 switched astrocytes from neuroprotective to pro-inflammatory property via binding to the receptor TNFR2. RGS5 also augmented TNFR signaling-mediated pro-inflammatory response by interacting with the receptor TNFR1. Moreover, interrupting RGS5/TNFR interaction by either RGS5 aa 1-108 or small molecular compounds feshurin and butein, suppressed astrocytic cytokine production. We showed that the transcription of astrocytic RGS5 was controlled by transcription factor early B cell factor 1 whose expression was reciprocally influenced by RGS5-modulated TNF signaling. Thus, our study indicates that beyond its traditional role in G-protein coupled receptor signaling, astrocytic RGS5 is a key modulator of TNF signaling circuit with resultant activation of astrocytes thereby contributing to chronic neuroinflammation. Blockade of the astrocytic RGS5/TNFR interaction is a potential therapeutic strategy for neuroinflammation-associated neurodegenerative diseases.

The increase of Nrf2 m6A modification induced by FTO downregulation promotes hippocampal neuron injury and aggravates the progression of epilepsy in a rat model.

Epilepsy is a common chronic neurological disorder characterized by widespread neuronal death. The purpose of this study was to investigate the role of nuclear factor erythroid 2-related factor 2 (Nrf2) m6A methylation in epilepsy. To create epileptic models, the rats were given Lithium chloride and pilocarpine, and isolated primary rat hippocampal neurons were cultured in an Mg2+ -free medium. The frequency of seizures was recorded in the epilepsy group of rats. The functional tests included TUNEL, MTT, and flow cytometry. Mechanistically, RNA degradation assay, RNA immunoprecipitation, and methylated RNA immunoprecipitation were performed. In epileptic models, Nrf2 and fat mass and obesity-associated (FTO) levels were downregulated, whereas YT521-B homology (YTH) domain family protein 2 (YTHDF2) was upregulated. Additionally, in epileptic models, there was a rise in the m6A methylation level of Nrf2 mRNA. Overexpressing FTO increased cell viability and reduced apoptosis, but Nrf2 interference reversed these effects. Meanwhile, FTO overexpression decreased the m6A methylation of Nrf2 mRNA. Moreover, YTHDF2 bound to Nrf2 mRNA and decreased its stability. Furthermore, FTO overexpression reduced seizure frequency in rats and inhibited hippocampal neuron apoptosis via lowering the m6A methylation level of Nrf2 mRNA. Overexpressing FTO reduced m6A methylation of Nrf2 mRNA, increased cell viability, suppressed apoptosis, and slowed the progression of epileptic diseases, which is linked to YTHDF2 binding to m6A-modified Nrf2 and promoting its degradation, as well as downregulating Nrf2 expression in hippocampal neurons.

VLPs containing stalk domain and ectodomain of matrix protein 2 of influenza induce protection in mice.

BACKGROUND: As a result of antigenic drift, current influenza vaccines provide limited protection against circulating influenza viruses, and vaccines with broad cross protection are urgently needed. Hemagglutinin stalk domain and ectodomain of matrix protein 2 are highly conserved among influenza viruses and have great potential for use as a universal vaccine. METHODS: In this study, we co-expressed the stalk domain and M2e on the surface of cell membranes and generated chimeric and standard virus-like particles of influenza to improve antigen immunogenicity. We subsequently immunized BALB/c mice through intranasal and intramuscular routes. RESULTS: Data obtained demonstrated that vaccination with VLPs elicited high levels of serum-specific IgG (approximately 30-fold higher than that obtained with soluble protein), induced increased ADCC activity to the influenza virus, and enhanced T cell as well as mucosal immune responses. Furthermore, mice immunized by VLP had elevated level of mucosal HA and 4M2e specific IgA titers and cytokine production as compared to mice immunized with soluble protein. Additionally, the VLP-immunized group exhibited long-lasting humoral antibody responses and effectively reduced lung viral titers after the challenge. Compared to the 4M2e-VLP and mHA-VLP groups, the chimeric VLP group experienced cross-protection against the lethal challenge with homologous and heterologous viruses. The stalk domain specific antibody conferred better protection than the 4M2e specific antibody. CONCLUSION: Our findings demonstrated that the chimeric VLPs anchored with the stalk domain and M2e showed efficacy in reducing viral loads after the influenza virus challenge in the mice model. This antibody can be used in humans to broadly protect against a variety of influenza virus subtypes. The chimeric VLPs represent a novel approach to increase antigen immunogenicity and are promising candidates for a universal influenza vaccine.

Simvastatin induces pyroptosis via ROS/caspase-1/GSDMD pathway in colon cancer.

BACKGROUND: The outcome of patients with colon cancer is still unsatisfied nowadays. Simvastatin is a type of statins with anti-cancer activity, but its effect on colon cancer cells remains unclear. The present study is intended to determine the underlying mechanism of simvastatin in treatment of colon cancer. METHODS: The viability and pyroptosis rate of cells treated and untreated with simvastatin were analysed by CCK-8 and flow cytometry assays, respectively. We used DCFH-DA and flow cytometry to detect reactive oxygen species (ROS) production. Levels of pyroptosis markers were detected by western blotting analysis or immunofluorescence staining. Besides, the anticancer properties of simvastatin on colon cancer were further demonstrated using a cell line based xenograft tumor model. RESULTS: Simvastatin treatment in HCT116 and SW620 induced pyroptosis and suppressed cell proliferation, with changes in the expression level of NLPR3, ASC, cleaved-caspase-1, mature IL-1ß, IL-18 and GSDMD-N. Moreover, inhibition of caspase-1 and ROS attenuated the effects of simvastatin on cancer cell viability. In addition, it was identified that simvastatin has an anti-tumor effect by down-regulating ROS production and inducing downstream caspase-1 dependent pyroptosis in the subcutaneous transplantation tumors of HCT116 cells in BALB/c nude mice. CONCLUSIONS: Our in vitro and in vivo results indicated that simvastatin induced pyroptosis through ROS/caspase-1/GSDMD pathway, thereby serving as a potential agent for colon cancer treatment. Video Abstract.

Glycemic Variability and the Risk of Diabetic Peripheral Neuropathy: A Meta-Analysis.

Glycemic variability (GV) has been related to complications in patients with diabetes. The aim of the systematic review and meta-analysis was to investigate whether GV is also associated with the incidence of diabetic peripheral neuropathy (DPN). A systematic search of Medline, Web of Science, Embase, and Cochrane Library database was conducted to identify relevant observational studies with longitudinal follow-up. The Newcastle-Ottawa Scale was used for study quality evaluation. A random-effects model was utilized to pool the results, accounting for heterogeneity. Ten observational studies including 72 565 patients with diabetes were included. The quality score was 8-9, indicating generally good quality of the included studies. With a mean follow-up duration of 7.1 years, 11 532 patients (15.9%) were diagnosed as DPN. Compared to patients with low GV, patients with high GV were associated with an increased risk incidence of DPN (risk ratio: 1.51, 95% confidence interval: 1.23 to 1.85, p<0.001; I2=78%). In addition, subgroup analysis showed consistent results in patients with type 1 and type 2 diabetes, and in studies evaluating the short-term and long-term GV (p for subgroup difference=0.82 and 0.53). Finally, results of subgroup analysis also suggested that the association between GV and risk of DPN were not significantly affected by study design, follow-up durations, diagnostic methods for DPN, adjustment of mean glycated hemoglobin A1c, or study quality scores (p for subgroup difference all>0.05). A high GV may be associated with an increased incidence of DPN.

Host-Guest Symmetry Matching in Two Crystalline Magnesium Sulfate Oxalates Obtained Via a Solvent-Free Route.

The combination of π-conjugated oxalate anion with sulfate group has been explored in the solvent-free synthesis of two new magnesium sulfate oxalates. One of them has a layered structure crystallized in the noncentrosymmetric space group Ia, while the other has a chainlike structure crystallized in the centrosymmetric space group P21/c. The noncentrosymmetric solid has a wide optical bandgap and exhibits a moderate second-harmonic-generation response. Density functional theory calculations were carried out to disclose the origin of its second-order nonlinear-optical response.

Two van der Waals Layered Antimony(III) Phosphites as UV Optical Materials.

Herein, two new Sb3+-based phosphites, Sb2O2(HPO3) (I) and Sb2O(HPO3)2 (II), were successfully obtained by ingeniously combining Sb3+-based polyhedra containing stereochemically active lone pair (SCALP) and HPO3 polar groups. Both reported compounds exhibit unique 2D van der Waals layered structures, [Sb4O4(HPO3)2]∞ and [Sb2O(HPO3)2]∞, respectively, which favors compounds with large optical anisotropy. Interestingly, the different curvatures of the two layers resulted in the two title compounds showing significantly different birefringences (0.079@546 and 0.046@546 nm, respectively). Both compounds endow wide optical band gaps (4.32 and 4.54 eV, respectively), which indicates their potential as promising ultraviolet (UV) birefringent crystals. The synthesis of the two title compounds enriched Sb3+-based phosphites in the UV region and provided guidance for the subsequent synthesis of superior optical materials.

Host-Guest Symmetry and Charge Matching in Glycine-Templated Metal Sulfate-Oxalates Obtained by a Solvent-Free Method.

Two metal sulfate-oxalates, (Hgly)2·Zn(SO4)(C2O4) (1) and Hgly·In(SO4)(C2O4)(gly) (2), were prepared under solvent-free conditions, where gly = glycine. They have similar layered structures despite the fact that aliovalent metal ions are used as structural nodes. Notably, glycine molecules play dual roles as a protonated cation and a zwitterionic ligand in compound 2. The two compounds display moderate second-harmonic-generation (SHG) responses, confirming their noncentrosymmetric structures. Theoretical calculations were performed to reveal the origin of their SHG responses.