A novel chemical probe based on the salamo-Co(II) complex for the highly selective fluorescence detection of tyrosine.

A new and rare Salamo-Co(II) complex probe L-Co2+ was designed and synthesised. The structure of the [Co3(L)2(µ-OAc)2(MeOH)2]⋅2H2O complex was obtained by X-ray diffraction experiments. Three Co(II) atoms are in a line in the complex, and all Co(II) atoms form a 6-coordinated octahedral configuration. The probe L-Co2+ selectively recognises tyrosine in DMF/H2O (8:2, v/v). Upon addition of tyrosine, the fluorescence intensity of L-Co2+ was enhanced in a short time. The probe showed high selectivity and sensitivity for tyrosine, detection limit is 4.27 × 10-8 M. The recognition mechanism of probe L-Co2+ for Tyr was inferred by FT-IR spectra, UV spectroscopy, ESI mass spectra and DFT calculations. Finally, due to the simplicity and specificity of the identification process, the probe was also subjected to a test paper experiment and a milk assay.

Designing novel ice creams using nut oil emulsion gels based on blueberry pectin and CaCl2 as fat replacers: Insights from physicochemical and sensory properties.

This study aimed to utilize blueberry pectin and calcium chloride to design a gel network structure for loading nut oils (peanut and walnut oil, respectively). The optimization of emulsion gel preparation was conducted through orthogonal experiments, utilizing the oil-holding ratio and gel strength as critical indicators. The emulsion gel was applied to the ice cream production. It was revealed that the peroxide value of the nut oil emulsion gels was significantly lower than that of nut oils. Both nut oil emulsion gel ice creams exhibited higher expansion rates, lower melting rates, and decreased hardness than the nut oil ice creams. Notably, walnut oil emulsion gel ice cream demonstrated a melting rate similar to traditional butter-based ice cream. Emulsion gel ice cream has higher fat globule instability and viscosity. Overall, the comprehensive emulsion gel ice cream indicators were comparable to conventional butter ice cream and notably superior to peanut and walnut oil ice cream. Using emulsion gel as a fat substitute in ice cream was feasible. The implications of these results were significant for advancing the utilization of nut oil emulsion gel within the ice cream industry.

Small-molecule GSDMD agonism in tumors stimulates antitumor immunity without toxicity.

Gasdermin-mediated inflammatory cell death (pyroptosis) can activate protective immunity in immunologically cold tumors. Here, we performed a high-throughput screen for compounds that could activate gasdermin D (GSDMD), which is expressed widely in tumors. We identified 6,7-dichloro-2-methylsulfonyl-3-N-tert-butylaminoquinoxaline (DMB) as a direct and selective GSDMD agonist that activates GSDMD pore formation and pyroptosis without cleaving GSDMD. In mouse tumor models, pulsed and low-level pyroptosis induced by DMB suppresses tumor growth without harming GSDMD-expressing immune cells. Protection is immune-mediated and abrogated in mice lacking lymphocytes. Vaccination with DMB-treated cancer cells protects mice from secondary tumor challenge, indicating that immunogenic cell death is induced. DMB treatment synergizes with anti-PD-1. DMB treatment does not alter circulating proinflammatory cytokine or leukocyte numbers or cause weight loss. Thus, our studies reveal a strategy that relies on a low level of tumor cell pyroptosis to induce antitumor immunity and raise the possibility of exploiting pyroptosis without causing overt toxicity.

Triple oxygen isotope reveals insolation-forced tropical moisture cycles.

Tropical oceans are the main global water vapor and latent heat sources, but their responses to radiative forcing remain unclear. Here, we investigate oceanic moisture dynamics of the western tropical Pacific (WTP) over the past 210,000 years through an approach of planktonic foraminiferal triple oxygen isotope (Δ'17O). The Δ'17O record is dominated by the precession cycles (~23,000 years), with lower values reflecting higher humidity in concert with higher Northern Hemisphere summer insolation. Our empirical and modeling results, combined with other geological archives, suggest that the enhanced moisture convergence over the WTP largely intensifies changes in the meridional and zonal hydrological cycles, affecting rainfall patterns in East Asia and northern South America. We propose that the insolation-driven WTP moisture dynamics play a pivotal role in regulating tropical hydroclimate.

Altered Cell Clusters and Upregulated Aqp1 in Connexin 50 Knockout Lens Epithelium.

Purpose: To characterize the heterogeneity and cell clusters of postnatal lens epithelial cells (LECs) and to investigate the downstream targets of connexin 50 (Cx50) in the regulation of lens homeostasis and lens growth. To determine differentially expressed genes (DEGs) in the connexin 50 knockout (Cx50KO) lens epithelial cells that shed light on novel mechanism underlying the cataract and small size of the Cx50KO lenses. Methods: Single-cell RNA sequencing (scRNA-seq) of lens epithelial cells isolated from one-month-old Cx50KO and wild-type (WT) mice were performed. Differentially expressed genes were identified, and selected DEGs were further studied by quantitative real-time PCR (RT-qPCR) analysis and Western blot analysis. Results: The expression profiles of several thousand genes were identified by scRNA-seq data analysis. In comparison to the WT control, many DEGs were identified in the Cx50KO lens epithelial cells, including growth regulating transcriptional factors and genes encoding water channels. Significantly upregulated aquaporin 1 (Aqp1) gene expression was confirmed by RT-qPCR, and upregulated AQP1 protein expression was confirmed by Western blot analysis and immunostaining both in vivo and in vitro. Conclusions: Lens epithelial cells exhibit an intrinsic heterogeneity of different cell clusters in regulating lens homeostasis and lens growth. Upregulated Aqp1 in Cx50KO lens epithelial cells suggests that both connexin 50 and AQP1 likely play important roles in regulating water homeostasis in lens epithelial cells.

Tumor editing suppresses innate and adaptive antitumor immunity and is reversed by inhibiting DNA methylation.

Cancer cells edit gene expression to evade immunosurveillance. However, genome-wide studies of gene editing during early tumorigenesis are lacking. Here we used single-cell RNA sequencing in a breast cancer genetically engineered mouse model (GEMM) to identify edited genes without bias. Late tumors repressed antitumor immunity genes, reducing infiltrating immune cells and tumor-immune cell communications. Innate immune genes, especially interferon-stimulated genes, dominated the list of downregulated tumor genes, while genes that regulate cell-intrinsic malignancy were mostly unedited. Naive and activated CD8+ T cells in early tumors were replaced with exhausted or precursor-exhausted cells in late tumors. Repression of immune genes was reversed by inhibiting DNA methylation using low-dose decitabine, which suppressed tumor growth and restored immune control, increasing the number, functionality and memory of tumor-infiltrating lymphocytes and reducing the number of myeloid suppressor cells. Decitabine induced important interferon, pyroptosis and necroptosis genes, inflammatory cell death and immune control in GEMM and implanted breast and melanoma tumors.

Upregulation of the Cav1.3 channel in inner hair cells by interleukin 6-dependent inflammaging contributes to age-related hearing loss.

Age-related hearing loss (AHL) is the most common sensory disorder amongst the older population. Inflammaging is a ≈chronic low-grade inflammation that worsens with age and is an early sign of AHL; however, the underlying mechanisms remain unclear. We used electrophysiological and genetic approaches to establish the importance of interleukin 6 (IL-6)-dependent inflammation in AHL. Elevated IL-6 in the cochlea enhanced Cav1.3 calcium channel function in the inner hair cell (IHC) synapse in mice with AHL. IL-6 upregulated the Cav1.3 channel via the Janus kinase-mitogen activated kinase pathway, causing neurotransmitter excitotoxicity and synapse impairment; IL-6 deficiency or the administration of a Cav1.3 channel blocker attenuated this age-related damage, and rescued hearing loss. Thus, IL-6-dependent inflammaging upregulated the Cav1.3 channel in IHCs, contributing to AHL. Our findings could help the comprehensive understanding of inflammaging's effects on AHL, aiding in early intervention to protect against hearing decline.

Contrast enhancement boost improves the image quality of CT angiography derived from 80-kVp cerebral CT perfusion data.

RATIONALE AND OBJECTIVE: To investigate the impact of the contrast enhancement boost (CE-boost) technique on the image quality of CT angiography (CTA) derived from 80-kVp cerebral CT perfusion (CTP) data, and to compare it with conventional CTApeak as well as other currently employed methods for enhancing CTA images, such as CTAtMIP and CTAtAve extracted from CTP. MATERIALS AND METHODS: The data of forty-seven patients who underwent CTP at 80 kVp were retrospectively collected. Four sets of images: CTApeak, CTAtMIP, CTAtAve, and CE-boost images. The CTApeak image represents the arterial phase at its peak value, captured as a single time point. CTAtMIP and CTAtAve are 4D CTA images that provide maximum density projection and average images from the three most prominent time points. CE-boost is a postprocessing technique used to enhance contrast in the arterial phase at its peak value. We compared the average CT value, standard deviation (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the internal carotid artery (ICA) and basilar artery (BA) among the four groups. Image quality was evaluated using a 5-point scale. RESULTS: The CE-boost demonstrated and CNR in the ICA and BA (all p < 0.001). Compared with the other three CTA reconstructed images, the CE-boost images had the best subjective image quality, with the highest scores of 4.77 ± 0.43 and 4.87 ± 0.34 for each reader (all p < 0.001). CONCLUSION: Compared with other currently used techniques,CE-boost enhances the image quality of CTA derived from 80-kVp CTP data, leading to improved visualization of intracranial arteries.

Co-Transplantation-Based Human-Mouse Chimeric Brain Models to Study Human Glial-Glial and Glial-Neuronal Interactions.

Human-mouse chimeric brain models, generated by transplanting human induced pluripotent stem cell (hiPSC)-derived neural cells, are valuable for studying the development and function of human neural cells in vivo. Understanding glial-glial and glial-neuronal interactions is essential for unraveling the complexities of brain function and developing treatments for neurological disorders. To explore these interactions between human neural cells within an intact brain environment, we employe a co-transplantation strategy involving the engraftment of hiPSC-derived neural progenitor cells along with primitive macrophage progenitors into the neonatal mouse brain. This approach creates human-mouse chimeric brains containing human microglia, macroglia (astroglia and oligodendroglia), and neurons. Using super-resolution imaging and 3D reconstruction techniques, we examine the dynamics between human neurons and glia, unveiling human microglia engulfing immature human neurons, microglia pruning synapses of human neurons, and significant interactions between human oligodendrocytes and neurons. Single-cell RNA sequencing analysis of the chimeric brain uncovers a close recapitulation of the human glial progenitor cell population, along with a dynamic stage in astroglial development that mirrors the processes found in the human brain. Furthermore, cell-cell communication analysis highlights significant neuronal-glial and glial-glial interactions, especially the interaction between adhesion molecules neurexins and neuroligins. This innovative co-transplantation model opens up new avenues for exploring the complex pathophysiological mechanisms underlying human neurological diseases. It holds particular promise for studying disorders where glial-neuronal interactions and non-cell-autonomous effects play crucial roles.

Ovarian function in patients with systemic lupus erythematosus: Pathogenesis, drug application and prospective therapies.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease in which multiple organs are damaged that prevails in fertile women. Currently, glucocorticoids and immunosuppressants are widely used to treat SLE patients. However, ovarian dysfunction occurs following the use of these drugs in women with SLE. Here, we summarize recent progress in terms of understanding ovarian injury, the effects of drug application and strategies to improve ovarian function in women with SLE. This review could be helpful to precisely cure SLE in women desiring to have offspring.

Curcumin attenuates lupus nephritis by inhibiting neutrophil migration via PI3K/AKT/NF-κB signalling pathway.

OBJECTIVE: To investigate the role of curcumin in the treatment of lupus nephritis (LN) by inhibiting the migration of neutrophils and the underlying mechanism involved. METHODS: Two lupus mouse models, MRL/lpr mice and R848-treated mice, were treated with 50 mg/kg curcumin by intraperitoneal injection. H&E and Masson staining were used to estimate histopathological changes in the kidney. Immunofluorescence was used to assess the deposition of immune complexes. The expression of inflammatory factors was detected by enzyme-linked immunosorbent assay (ELISA) and real-time reverse transcription polymerase reaction (RT-PCR), and the protein expression was detected by western blotting. RESULTS: We revealed the remarkable potential of curcumin in improving inflammatory conditions in both MRL/lpr mice and R848-induced lupus mice. Curcumin effectively decelerates the progression of inflammation and diminishes the infiltration of neutrophils and their release of pivotal inflammatory factors, thereby reducing inflammation in renal tissues. Mechanistically, curcumin significantly inhibits the expression of p-PI3K, p-AKT and p-NF-κB, which are upregulated by interleukin-8 to induce neutrophil migration and renal inflammation, thereby reducing neutrophil migration and the release of inflammatory factors. CONCLUSION: Curcumin significantly inhibits the recruitment of neutrophils and the release of proinflammatory factors in the kidney by inhibiting the PI3K/AKT/NF-κB signalling pathway, providing new therapeutic targets and medication strategies for the treatment of LN.

First insights into the age of the giant ice deposits in the Eisriesenwelt cave (Austria).

Frozen water is the most widespread type of ice present in ice caves and forms ice stalagmites and stalactites as well as floor ice, which is often several meters thick. Organic macroremains are commonly rare in this type of cave ice, which makes it difficult to establish a chronology and severely limits the use of such ice deposits as paleoenvironmental archives. Here, the chronology of such ice deposits in the inner part of the glaciated Eisriesenwelt, one of the world's largest ice caves located in the European Alps of Austria, is determined by a combination of radiocarbon and 230Th dating of cryogenic calcite. The data suggest that this cave ice has formed over the last three millennia, with a marked increase in the average accumulation rate during the thirteenth century, coinciding with the onset of the Little Ice Age in the Alps. Data from a second site closer to the entrance suggests that large parts of this tourist cave were likely ice-free during the Medieval Warm Period and that a substantial part of the ice is probably a relic of the Little Ice Age. The current warming has already penetrated deeper into the cave than during the Medieval Warm Period, although air exchange during the warm season is restricted by a door at the cave entrance.

Potent human neutralizing antibodies against Nipah virus derived from two ancestral antibody heavy chains.

Nipah virus (NiV) is a World Health Organization priority pathogen and there are currently no approved drugs for clinical immunotherapy. Through the use of a naïve human phage-displayed Fab library, two neutralizing antibodies (NiV41 and NiV42) targeting the NiV receptor binding protein (RBP) were identified. Following affinity maturation, antibodies derived from NiV41 display cross-reactivity against both NiV and Hendra virus (HeV), whereas the antibody based on NiV42 is only specific to NiV. Results of immunogenetic analysis reveal a correlation between the maturation of antibodies and their antiviral activity. In vivo testing of NiV41 and its mature form (41-6) show protective efficacy against a lethal NiV challenge in hamsters. Furthermore, a 2.88 Å Cryo-EM structure of the tetrameric RBP and antibody complex demonstrates that 41-6 blocks the receptor binding interface. These findings can be beneficial for the development of antiviral drugs and the design of vaccines with broad spectrum against henipaviruses.

A Trisomy 21-linked Hematopoietic Gene Variant in Microglia Confers Resilience in Human iPSC Models of Alzheimer's Disease.

While challenging, identifying individuals displaying resilience to Alzheimer's disease (AD) and understanding the underlying mechanism holds great promise for the development of new therapeutic interventions to effectively treat AD. Down syndrome (DS), or trisomy 21, is the most common genetic cause of AD. Interestingly, some people with DS, despite developing AD neuropathology, show resilience to cognitive decline. Furthermore, DS individuals are at an increased risk of myeloid leukemia due to somatic mutations in hematopoietic cells. Recent studies indicate that somatic mutations in hematopoietic cells may lead to resilience to neurodegeneration. Microglia, derived from hematopoietic lineages, play a central role in AD etiology. We therefore hypothesize that microglia carrying the somatic mutations associated with DS myeloid leukemia may impart resilience to AD. Using CRISPR-Cas9 gene editing, we introduce a trisomy 21-linked hotspot CSF2RB A455D mutation into human pluripotent stem cell (hPSC) lines derived from both DS and healthy individuals. Employing hPSC-based in vitro microglia culture and in vivo human microglia chimeric mouse brain models, we show that in response to pathological tau, the CSF2RB A455D mutation suppresses microglial type-1 interferon signaling, independent of trisomy 21 genetic background. This mutation reduces neuroinflammation and enhances phagocytic and autophagic functions, thereby ameliorating senescent and dystrophic phenotypes in human microglia. Moreover, the CSF2RB A455D mutation promotes the development of a unique microglia subcluster with tissue repair properties. Importantly, human microglia carrying CSF2RB A455D provide protection to neuronal function, such as neurogenesis and synaptic plasticity in chimeric mouse brains where human microglia largely repopulate the hippocampus. When co-transplanted into the same mouse brains, human microglia with CSF2RB A455D mutation phagocytize and replace human microglia carrying the wildtype CSF2RB gene following pathological tau treatment. Our findings suggest that hPSC-derived CSF2RB A455D microglia could be employed to develop effective microglial replacement therapy for AD and other age-related neurodegenerative diseases, even without the need to deplete endogenous diseased microglia prior to cell transplantation.

ABIN1 (Q478) is Required to Prevent Hematopoietic Deficiencies through Regulating Type I IFNs Expression.

A20-binding inhibitor of NF-κB activation (ABIN1) is a polyubiquitin-binding protein that regulates cell death and immune responses. Although Abin1 is located on chromosome 5q in the region commonly deleted in patients with 5q minus syndrome, the most distinct of the myelodysplastic syndromes (MDSs), the precise role of ABIN1 in MDSs remains unknown. In this study, mice with a mutation disrupting the polyubiquitin-binding site (Abin1Q478H/Q478H ) is generated. These mice develop MDS-like diseases characterized by anemia, thrombocytopenia, and megakaryocyte dysplasia. Extramedullary hematopoiesis and bone marrow failure are also observed in Abin1Q478H/Q478H mice. Although Abin1Q478H/Q478H cells are sensitive to RIPK1 kinase-RIPK3-MLKL-dependent necroptosis, only anemia and splenomegaly are alleviated by RIPK3 deficiency but not by MLKL deficiency or the RIPK1 kinase-dead mutation. This indicates that the necroptosis-independent function of RIPK3 is critical for anemia development in Abin1Q478H/Q478H mice. Notably, Abin1Q478H/Q478H mice exhibit higher levels of type I interferon (IFN-I) expression in bone marrow cells compared towild-type mice. Consistently, blocking type I IFN signaling through the co-deletion of Ifnar1 greatly ameliorated anemia, thrombocytopenia, and splenomegaly in Abin1Q478H/Q478H mice. Together, these results demonstrates that ABIN1(Q478) prevents the development of hematopoietic deficiencies by regulating type I IFN expression.

Identification and Characterization of Retinitis Pigmentosa in a Novel Mouse Model Caused by PDE6B-T592I.

The cGMP-phosphodiesterase 6 beta subunit (PDE6B) is an essential component in the phototransduction pathway for light responses in photoreceptor cells. PDE6B gene mutations cause the death of rod photoreceptors, named as hereditary retinitis pigmentosa (RP) in humans and retinal degeneration (RD) in rodents. Here, we report a new RD model, identified from a phenotypic screen of N-ethyl-N-nitrosourea (ENU)-induced mutant mice, which displays retinal degeneration caused by a point mutation in the Pde6b gene that results in PDE6B-T592I mutant protein. The homozygous mutant mice show an extensive loss of rod photoreceptors at the age of 3 weeks; unexpectedly, the loss of rod photoreceptors can be partly rescued by dark rearing. Thus, this RD mutant model displays a light-dependent loss of rod photoreceptors. Both western blot and immunostaining results show very low level of mutant PDE6B-T592I protein in the retina. Structure modeling suggests that the T592I mutation probably affects the function and stability of PDE6B protein by changing intramolecular interactions. We further demonstrate that the expression of wild-type PDE6B delivered by subretinally injected adeno-associated virus (rAAV) prevents photoreceptor cell death in this RD model in vivo. The PDE6B-T592I mutant is, therefore, a valuable RD model for evaluating rAAV-mediated treatment and for investigating the molecular mechanism of light-dependent rod photoreceptor cell death that is related to impaired PDE6B function.

Gasdermin D permeabilization of mitochondrial inner and outer membranes accelerates and enhances pyroptosis.

Gasdermin D (GSDMD)-activated inflammatory cell death (pyroptosis) causes mitochondrial damage, but its underlying mechanism and functional consequences are largely unknown. Here, we show that the N-terminal pore-forming GSDMD fragment (GSDMD-NT) rapidly damaged both inner and outer mitochondrial membranes (OMMs) leading to reduced mitochondrial numbers, mitophagy, ROS, loss of transmembrane potential, attenuated oxidative phosphorylation (OXPHOS), and release of mitochondrial proteins and DNA from the matrix and intermembrane space. Mitochondrial damage occurred as soon as GSDMD was cleaved prior to plasma membrane damage. Mitochondrial damage was independent of the B-cell lymphoma 2 family and depended on GSDMD-NT binding to cardiolipin. Canonical and noncanonical inflammasome activation of mitochondrial damage, pyroptosis, and inflammatory cytokine release were suppressed by genetic ablation of cardiolipin synthase (Crls1) or the scramblase (Plscr3) that transfers cardiolipin to the OMM. Phospholipid scramblase-3 (PLSCR3) deficiency in a tumor compromised pyroptosis-triggered anti-tumor immunity. Thus, mitochondrial damage plays a critical role in pyroptosis.

Excessive apoptosis of Rip1-deficient T cells leads to premature aging.

In mammals, the most remarkable T cell variations with aging are the shrinking of the naïve T cell pool and the enlargement of the memory T cell pool, which are partially caused by thymic involution. However, the mechanism underlying the relationship between T-cell changes and aging remains unclear. In this study, we find that T-cell-specific Rip1 KO mice show similar age-related T cell changes and exhibit signs of accelerated aging-like phenotypes, including inflammation, multiple age-related diseases, and a shorter lifespan. Mechanistically, Rip1-deficient T cells undergo excessive apoptosis and promote chronic inflammation. Consistent with this, blocking apoptosis by co-deletion of Fadd in Rip1-deficient T cells significantly rescues lymphopenia, the imbalance between naïve and memory T cells, and aging-like phenotypes, and prolongs life span in T-cell-specific Rip1 KO mice. These results suggest that the reduction and hyperactivation of T cells can have a significant impact on organismal health and lifespan, underscoring the importance of maintaining T cell homeostasis for healthy aging and prevention or treatment of age-related diseases.

Treatment of autosomal dominant retinitis pigmentosa caused by RHO-P23H mutation with high-fidelity Cas13X in mice.

Mutations in Rhodopsin (RHO) gene commonly cause autosomal dominant retinitis pigmentosa (adRP) without effective therapeutic treatment so far. Compared with genomic DNA-targeting CRISPR-Cas9 system, Cas13 edits RNA for therapeutic applications, avoiding the risk of causing permanent changes in the genome. In particular, a compact and high-fidelity Cas13X (hfCas13X) recently has been developed to degrade targeted RNA with minimal collateral effects and could also be packaged in a single adeno-associated virus for efficient in vivo delivery. In this study, we engineered single-guide RNA for hfCas13X to specifically knock down human mutant Rhodopsin transcripts RHO-P23H with minimal effect on wild-type transcripts. Moreover, treatment with hfCas13X alleviated the adRP progression in both RHO-P23H overexpression-induced and humanized hRHOP23H/WT mouse models. Our study indicates the potential of hfCas13X in treating adRP caused by RHO mutations and other genetic diseases.

Holocene climate change in southern Oman deciphered by speleothem records and climate model simulations.

Qunf Cave oxygen isotope (δ18Oc) record from southern Oman is one of the most significant of few Holocene Indian summer monsoon cave records. However, the interpretation of the Qunf δ18Oc remains in dispute. Here we provide a multi-proxy record from Qunf Cave and climate model simulations to reconstruct the Holocene local and regional hydroclimate changes. The results indicate that besides the Indian summer monsoon, the North African summer monsoon also contributes water vapor to southern Oman during the early to middle Holocene. In principle, Qunf δ18Oc values reflect integrated oxygen-isotope fractionations over a broad moisture transport swath from moisture sources to the cave site, rather than local precipitation amount alone, and thus the Qunf δ18Oc record characterizes primary changes in the Afro-Asian monsoon regime across the Holocene. In contrast, local climate proxies appear to suggest an overall slightly increased or unchanged wetness over the Holocene at the cave site.