Constructing Lanthanide-Organic Complexes for X-ray Scintillation and Imaging.

The photoluminescent properties of lanthanide complexes have been thoroughly investigated; however, there have been much fewer studies showcasing their potential use in ionizing radiation detection. In this work, we delve into the photo- and radio-induced luminescence of a series of lanthanide-bearing organic-inorganic hybrids and their potential as a platform for X-ray scintillation and imaging. The judicious synergy between lanthanide cations and 2,6-di(1H-pyrazol-1-yl)isonicotinate (bppCOO-) ligands affords six new materials with three distinct structures. Notably, Eu-bppCOO-1 and Tb-bppCOO-2 display sharp fingerprint X-ray-excited luminescence (XEL), the intensities of which can be linearly correlated with the X-ray dose rates over a broad dynamic range (0.007-4.55 mGy s-1). Moreover, the X-ray sensing efficacies of Eu-bppCOO-1 and Tb-bppCOO-2 were evaluated, showing that Tb-bppCOO-2 features a lower detection limit of 4.06 µGy s-1 compared to 14.55 µGy s-1 of Eu-bppCOO-1. Given the higher X-ray sensitivity and excellent radiation stability of Tb-bppCOO-2, we fabricated a flexible scintillator film for X-ray imaging by embedding finely ground Tb-bppCOO-2 in the polydimethylsiloxane (PDMS) polymer. The resulting scintillator film can be utilized for high-resolution X-ray imaging with a spatial resolution of approximately 7 lp mm-1.

Lanthanide Organic-Inorganic Hybrids for X-ray Scintillation and Imaging.

Two X-ray scintillators based on organic-inorganic hybrids were constructed by judiciously incorporating lanthanide cations and organic ligands within a single material. The obtained Eu-pba and Tb-pba not only feature excellent radiation, hydrolytic, and thermal stabilities but also exhibit a linear response to the X-ray dose rate with detection limits of 4.92 and 3.17 µGy s-1, respectively. We further present a flexible scintillator film fabricated by embedding Tb-pba in a polydimethylsiloxane (PDMS) polymer. Their incorporation enables X-ray imaging with a spatial resolution of approximately 10 lp mm-1. These results emphasize the potential of lanthanide organic-inorganic hybrids to achieve outstanding performance in X-ray scintillation and imaging.

Glycyrrhizin ameliorates impaired glucose metabolism and ovarian dysfunction in a polycystic ovary syndrome mouse model.

The aim of this study was to determine the impact of glycyrrhizin, an inhibitor of high mobility group box 1, on glucose metabolic disorders and ovarian dysfunction in mice with polycystic ovary syndrome. We generated a polycystic ovary syndrome mouse model by using dehydroepiandrosterone plus high-fat diet. Glycyrrhizin (100 mg/kg) was intraperitoneally injected into the polycystic ovary syndrome mice and the effects on body weight, glucose tolerance, insulin sensitivity, estrous cycle, hormone profiles, ovarian pathology, glucolipid metabolism, and some molecular mechanisms were investigated. Increased number of cystic follicles, hormonal disorders, impaired glucose tolerance, and decreased insulin sensitivity in the polycystic ovary syndrome mice were reverted by glycyrrhizin. The increased high mobility group box 1 levels in the serum and ovarian tissues of the polycystic ovary syndrome mice were also reduced by glycyrrhizin. Furthermore, increased expressions of toll-like receptor 9, myeloid differentiation factor 88, and nuclear factor kappa B as well as reduced expressions of insulin receptor, phosphorylated protein kinase B, and glucose transporter type 4 were restored by glycyrrhizin in the polycystic ovary syndrome mice. Glycyrrhizin could suppress the polycystic ovary syndrome-induced upregulation of high mobility group box 1, several inflammatory marker genes, and the toll-like receptor 9/myeloid differentiation factor 88/nuclear factor kappa B pathways, while inhibiting the insulin receptor/phosphorylated protein kinase B/glucose transporter type 4 pathways. Hence, glycyrrhizin is a promising therapeutic agent against polycystic ovary syndrome.

Emodin improves glucose metabolism and ovarian function in PCOS mice via the HMGB1/TLR4/NF-κB molecular pathway.

In brief: Obese PCOS mice display metabolic and endocrine disorders that manifest as abnormal metabolism of glucose and dysfunctions in the reproductive system. This study demonstrates that emodin alleviates most of these conditions possibly via the HMGB1/TLR4/NF-kB pathway. Abstract: PCOS is a reproductive disorder with an unclear etiology. It affects 5-10% of women worldwide and is largely associated with impaired glucose metabolism and obesity. HMGB1 is a nuclear protein associated with impaired glucose metabolism and PCOS. We sought to investigate the potential therapeutic effects of emodin on glucose metabolism and ovarian functions in PCOS mice via the HMGB1 molecular pathway. A high-fat diet (HFD) and dehydroepiandrosterone (DHEA)- induced PCOS mouse model comprising four experimental groups was established: control, PCOS, PCOS plus emodin, and PCOS plus vehicle groups. Emodin administration attenuated obesity, elevated fasting glucose levels, impaired glucose tolerance, and insulin resistance, and improved the polycystic ovarian morphology of PCOS mice. Additionally, it lowered elevated serum HMGB1, LH, and testosterone levels in PCOS mice. Elevated ovarian protein and mRNA levels of HMGB1 and TLR4 in PCOS mice were also lowered following emodin treatment. Furthermore, emodin lowered high NF-ĸB/65 protein levels in the ovaries of PCOS mice. Immunohistochemical staining of the ovaries revealed strong HMGB1, TLR4, and AR expressions in PCOS mice, which were lowered by emodin treatment. Moreover, emodin significantly increased GLUT4, IRS2, and INSR levels that were lowered by PCOS. Overall, our study showed that emodin alleviated the impaired glucose metabolism and improved ovarian function in PCOS mice, possibly via the HMGB1/TLR4/NF-ĸB signaling pathway. Thus, emodin could be considered a potential therapeutic agent in the management of PCOS.

Adsorption and Detection of Iodine Species by a Thorium-Based Metal-Organic Framework.

Actinide-bearing metal-organic frameworks (MOFs) encompass intriguing structures and properties, but the radioactivity of actinide cripples their applications. Herein, we have constructed a new thorium-based MOF (Th-BDAT) as a bifunctional platform for the adsorption and detection of radioiodine, a more radioactive fission product that can readily spread through the atmosphere in its molecular form or via solution as anionic species. The iodine capture within the framework of Th-BDAT from both the vapor phase and the cyclohexane solution has been verified, showing that Th-BDAT features maximum I2 adsorption capacities (Qmax) of 959 and 1046 mg/g, respectively. Notably, the Qmax of Th-BDAT toward I2 from cyclohexane solution ranks among the highest value for Th-MOFs reported to date. Furthermore, incorporating highly extended and π-electron-rich BDAT4- ligands renders Th-BDAT as a luminescent chemosensor whose emission can be selectively quenched by iodate with a detection limit of 1.367 µM. Our findings thus foreshadow promising directions that might unlock the full potential of actinide-based MOFs from the point of view of practical application.

A decrease in cluster of differentiation 2 expression on natural killer cells is associated with polycystic ovary syndrome but not influenced by metformin in a mouse model†.

PROBLEM: Natural killer (NK) cells from the peripheral blood and spleen represent the source from which various tissues replenish their immune cell populations. Hyperandrogenism and high interleukin-2 (IL-2) levels are factors present in polycystic ovary syndrome (PCOS). These factors and metformin, one of the commonest medications used in treating PCOS, may have an impact on NK cells. However, this is presently unknown. Here, we aimed to assess the distribution of peripheral blood and splenic NK cells and their CD2 and CD94 expression patterns in a PCOS mouse model and test whether metformin could reverse these effects. METHOD OF STUDY: Four mouse groups were designed as follows (n = 15/group): control, PCOS, PCOS plus vehicle, PCOS plus metformin. Dehydroepiandrosterone and a high-fat diet were administered to induce the PCOS mouse model. Flow cytometry was used to analyze the expressions of CD2 and CD94 on peripheral blood and splenic NK cells. RESULTS: PCOS mice had a low surface-density of CD2 on peripheral blood NK cells and a decreased percentage of CD2+ splenic NK cells. Metformin administration did not significantly influence these changes; however, it reduced the splenic NK cell counts. CONCLUSIONS: Our findings proved the association of PCOS with an altered expression of CD2 on peripheral blood and splenic NK cells and that of metformin with a lowered splenic NK cell reserve in PCOS conditions. These findings could further unlock key mechanisms in PCOS pathophysiology and in the mechanism of action of metformin, towards improving PCOS management.

Ovarian inflammatory mRNA profiles of a dehydroepiandrosterone plus high-fat diet-induced polycystic ovary syndrome mouse model.

RESEARCH QUESTION: What is the expression pattern of inflammatory mRNA profiles of a dehydroepiandrosterone (DHEA) plus high-fat diet (HFD)-induced polycystic ovary syndrome (PCOS) mouse model? DESIGN: RNA sequencing was performed to investigate the mRNA expression profiles in the ovarian tissues of a DHEA plus HFD-induced PCOS mouse model. Six samples were divided into two groups (control and PCOS), with three biological replicates in each group. This was followed by hierarchical clustering, gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses. The relative expression levels of nine inflammatory genes were validated via quantitative reverse-transcription polymerase chain reaction. RESULTS: A total of 436 genes were differentially expressed between the control and PCOS mice. Out of these, 137 genes were up-regulated while 299 genes were down-regulated. Gene ontology analysis indicated that differentially expressed mRNA were associated with T cell-mediated cytotoxicity and homocysteine metabolic processes. Pathway analysis further showed that these abnormally expressed mRNA were associated with signalling pathways, such as NF-kB signalling, tyrosine metabolism and phenylalanine metabolism. All these pathways are involved in chronic inflammation and PCOS. CONCLUSION: The differentially expressed genes are potentially involved in the inflammation that is evident in PCOS, and so could serve as therapeutic options against the disease. Nevertheless, prospective studies are needed to test this hypothesis.

A ratiometric radio-photoluminescence dosimeter based on a radical excimer for X-ray detection.

A novel radio-photoluminescence material featuring fluorochromic responses toward UV or X-ray irradiation has been obtained. Such a unique monomer- to excimer-based luminescence transition allows for dosimetry of ionizing radiation in a ratiometric manner. Rather than quenching the luminescence, the radiation-induced radical species of Th-105 boost the excimer emission, rendering it as a rare material possessing radical-excimers.

Incorporating Photochromic Viologen Derivative to Unprecedentedly Boost UV Sensitivity in Photoelectrochromic Hydrogel.

Developing ultraviolet (UV) radiation sensors featuring high sensitivity, ease of operation, and rapid readout is highly desired in diverse fields. However, the strategies to enhance sensitivity of UV detection remain limited particularly for photochromic materials, which show colorimetric response toward UV irradiation. Guided by our initial goal of facilitating easier handling, we formulated a viologen derivative ([H2L]-SC) incorporating hydrogel-based UV sensor which not only inherits the photochromism of [H2L]-SC but also engenders an unprecedented reversible photoelectrochromic response that is absent in either [H2L]-SC or hydrogel alone. Judicious synergy between photochromic [H2L]-SC and polyacrylamide (PAM) converts the colorimetric response of [H2L]-SC into the electrical resistance change of [H2L]-SC@PAM, which amplifies the UV sensitivity of [H2L]-SC by 2 orders of magnitude. Explicitly, the limit of detection (LOD) for UV decreases from 296.3 mJ/cm2 based on the UV-vis absorption spectra of [H2L]-SC to 2.83 mJ/cm2 derived from the resistance variation of [H2L]-SC@PAM. Moreover, linear correlation between the resistance reduction rate of [H2L]-SC@PAM and UV dose rate can be established, rendering it as a dual platform for quantifying both the accumulated UV dose and the instant dose rate. In addition, the proposed strategy based on constructing photoelectrochromic hybrids offers a new pathway to boost the UV sensitivity that could be universal for other photochromic materials.

Effects of Yulin Tong Bu formula on modulating gut microbiota and fecal metabolite interactions in mice with polycystic ovary syndrome.

Background: Polycystic ovarian syndrome (PCOS) is a common endocrine disorder characterized by hyperandrogenism, ovarian dysfunction and polycystic ovarian morphology. Gut microbiota dysbiosis and metabolite are associated with PCOS clinical parameters. Yulin Tong Bu formula (YLTB), a traditional Chinese medicine formula, has been recently indicated to be capable of ameliorating polycystic ovary symptoms and correcting abnormal glucose metabolism. However, the therapeutic mechanism of YLTB on PCOS has not been fully elucidated. Methods: A pseudo sterile mouse model was established during this four-day acclimatization phase by giving the animals an antibiotic cocktail to remove the gut microbiota. Here, the therapeutic effects of YLTB on PCOS were investigated using dehydroepiandrosterone plus high-fat diet-induced PCOS mice model. Female prepuberal mice were randomly divided into three groups; namely, the control group, PCOS group and YLTB (38.68 g·kg-1·day-1) group. To test whether this effect is associated with the gut microbiota, we performed 16S rRNA sequencing studies to analyze the fecal microbiota of mice. The relationships among metabolites, gut microbiota, and PCOS phenotypes were further explored by using Spearman correlation analysis. Then, the effect of metabolite ferulic acid was then validated in PCOS mice. Results: Our results showed that YLTB treatment ameliorated PCOS features (ovarian dysfunction, delayed glucose clearance, decreased insulin sensitivity, deregulation of glucolipid metabolism and hormones, etc.) and significantly attenuated PCOS gut microbiota dysbiosis. Spearman correlation analysis showed that metabolites such as ferulic acid and folic acid are negatively correlated with PCOS clinical parameters. The effect of ferulic acid was similar to that of YLTB. In addition, the bacterial species such as Bacteroides dorei and Bacteroides fragilis were found to be positively related to PCOS clinical parameters, using the association study analysis. Conclusion: These results suggest that YLTB treatment systematically regulates the interaction between the gut microbiota and the associated metabolites to ameliorate PCOS, providing a solid theoretical basis for further validation of YLTB effect on human PCOS trials.

Corrigendum: Effects of Yulin Tong Bu formula on modulating gut microbiota and fecal metabolite interactions in mice with polycystic ovary syndrome.

[This corrects the article DOI: 10.3389/fendo.2023.1122709.].