[Heavy Metal Pollution and Health Risk Assessment in Karst Basin Around a Lead-Zinc Mine].

Water quality is one of the most important environmental issues in the sustainable development of karst areas. To investigate heavy metal pollution and assess health risk in karst water basins around mines, 18 groups of water samples were collected from the river and groundwater in the Sidi River karst basin, and the concentrations of nine types of heavy metals(Cu, Pb, Zn, Cd, Mn, Fe, As, Cr, and Sr) were determined. Sample data were analyzed using principal component analysis, correlation analysis, water quality index, the Nemerow comprehensive pollution index, hazard quotient, and hazard index. The results showed that the Sidi River was slightly alkaline. The farther the river water samples were from the tailings reservoir, the lower were the concentrations of Cu, Pb, Zn, Cd, Mn, Fe, As, and Sr in the river water. Principal component and correlation analyses showed that heavy metals in the Sidi River karst basin mainly came from mine discharge(55.42%), carbonate weathering dissolution(21.41%), and human activities(14.72%). Eighty-two percent of the samples in the river and all the samples in the groundwater were excellent water. The Nemerow comprehensive pollution index in the river was 4.12 with strong pollution. All the hazard indices were below 1, and Pb, Zn, As, Cd, and Cr were potentially threatening metals in the Sidi River karst basin. The concentration of heavy metals changed significantly after entering the karst conduit, indicating that the unique properties of the karst aquifer affected the spatial variation of the heavy metal concentration. The results of this study can provide data reference for water resource prevention and human health protection in the Sidi River karst basin and similar karst basins.

A Cancer Cell Selective Replication Stress Nano Amplifier Promotes Replication Fork Catastrophe to Overcome Radioresistance.

Replication stress (RS) induced by DNA damage plays a significant role in conferring the anticancer effects of radiotherapy and is tightly associated with radioresistance of cancer cells. Amplification of RS represents an effective approach to improving the efficacy of radiotherapy, although the development of selective RS amplifiers remains an unexplored frontier. We herein present an RS nano amplifier (RSNA) consisting of a catalytic FePt nanoparticle loaded with the chemotherapeutic doxorubicin (DOX), which selectively exacerbates RS in cancer cells by promoting replication fork (RF) catastrophe. RSNA converts the excessive reactive oxygen species (ROS) in cancer cells into oxygen, enhancing the DNA-damaging effects of radiotherapy to create more template lesions that impede RF progression in coalition with DOX. After radiation, ROS scavenging by RSNA accelerates RF progression through damaged template strands, increasing the frequency of RF collapse into double-strand breaks. Moreover, pretreatment with RSNA accumulates cancer cells in the S phase, exposing more RFs to radiation-induced RS. These effects of RSNA convergently maximize RS in cancer cells, effectively overcoming the radioresistance of cancer cells without affecting normal cells. Our study demonstrates the feasibility of selectively amplifying RS to boost radiotherapy.

Porphyromonas gingivalis induces an inflammatory response via the cGAS-STING signaling pathway in a periodontitis mouse model.

Periodontitis is an inflammatory disease initiated by periodontopathogenic bacteria in the dental plaque biofilms. Understanding the role of Porphyromonas gingivalis (P. gingivalis), a keystone pathogen associated with chronic periodontitis, in the inflammatory response is crucial. Herein, we investigated whether P. gingivalis infection triggers the expression of the type I IFN gene and various cytokines and leads to activation of the cGAMP synthase-stimulator of IFN genes (cGAS-STING) pathway both in vitro and in a mouse model. Additionally, in an experimental model of periodontitis using P. gingivalis, StingGt mice showed lower levels of inflammatory cytokines and bone resorption than wild-type mice. Furthermore, we report that a STING inhibitor (SN-011) significantly decreased inflammatory cytokine production and osteoclast formation in a periodontitis mouse model with P. gingivalis. In addition, STING agonist (SR-717) -treated periodontitis mice displayed enhanced macrophage infiltration and M1 macrophage polarization in periodontal lesions compared with that in vehicle-treated periodontitis mice. In conclusion, our results demonstrate that the cGAS-STING signaling pathway may be one of the key mechanisms crucial for the P. gingivalis-induced inflammatory response that leads to chronic periodontitis.

[Correlation analysis of serum CTRP3 and PGC-1α expression with traumatic fracture healing].

OBJECTIVE: To investigate the relationship between serum C1q/tumor necrosis factor-related protein-3(CTRP3) and peroxisome proliferator-activated receptor γ coactivator-1α(PGC-1α) on predictive value of expression level on fracture healing. METHODS: From January 2019 to January 2020, 80 patients with traumatic tibial plateau fractures were treated by internal fixation with support plates through the posterior approach of the knee joint. The patients were followed up for 12 months. According to the criteria for delayed fracture healing, the patients were divided into two groups:54 patients in fracture healing group included 24 males and 30 females, aged 29 to 75 years old with an average of (52.36±13.17) years;In the delayed healing group, there were 26 cases, 13 males and 13 females, aged from 29 to 75 with an average od (53.82±13.52) years. The serum levels of CTRP3, PGC-1αand 25 hydroxyvitamin D3[25(OH)D3] in patients with traumatic fracture were detected by enzyme-linked immunosorbent assay(ELISA);Blood phosphorus and calcium levels were measured by automatic biochemical analyzer, and the product of calcium and phosphorus was calculated;Pearson's method was used to analyze the correlation between serum CTRP3, PGC-1αand bone biochemical indexes in patients with delayed union one week after operation;The predictive value of serum levels of CTRP3 and PGC-1αon traumatic fracture healing was analyzed by receiver operating characteristic curve(ROC curve). RESULTS: PGC-1α, calcium phosphorus product and 25(OH)D3 in the fracture healing group were higher than those in the delayed healing group at 1 and 4 weeks after operation(P<0.05). Serum CTRP3 was positively correlated with PGC-1α(r=0.637, P<0.05) and positively correlated with calcium phosphorus product and 25(OH)D3(P<0.05). The areas under the curve(AUC) of serum ctrp3 and PGC-1α levels in predicting traumatic fracture healing were 0.845 and 0.855, respectively. The cutoff values were 188.678 pg/ml and 2.697 ng/ml, respectively. The specificity was 96.2% and 80.8%, and the sensitivity was 53.7% and 77.8%;The predicted AUC was 0.904, the specificity was 88.5%, and the sensitivity was 81.5%. CONCLUSION: The serum levels of CTRP3 and PGC-1 in patients with delayed union of traumatic fracture at 1 and 4 weeks after operation α The expression level is of certain reference value to predict the fracture healing status of patients.

Dissolved Heavy Metal Pollution and Assessment of a Karst Basin around a Mine, Southwest China.

Karst water quality is one of the most important environmental issues in karst areas. The study's purpose was to investigate dissolved heavy metal pollution and health risk assessment in karst water basins around mines. River water and groundwater samples were analyzed by principal component analysis, correlation analysis, water quality index, hazard quotient, and hazard index. Median concentrations of dissolved heavy metals in the Sidi River were similar to the world average with a slightly alkaline characteristic. The concentrations of most dissolved heavy metals in river water were higher than those in groundwater. The concentrations of Zn, Pb, and Cd around the mine exceeded the limits of drinking water indicators. The poor water quality samples with high water quality index values were distributed around the mine. Lead (Pb), Zn, As, Cd, and Cr were potentially threatening metals in the study area. The pollution level of dissolved heavy metals in the Sidi River was at a medium level compared with other rivers worldwide. Principal component analysis and correlation analysis showed that Cu, Pb, Zn, Cd, Mn, Fe, As, and Sr mainly came from mine drainage; Ca2+, Mg2+, and Cr mainly came from the contribution of carbonate rocks; Na+ and K+ were related to local human agricultural activities. The concentrations of dissolved heavy metals in groundwater were affected by karst aquifers. The results of this study can provide a data reference for water resources prevention and human health protection in the Sidi River's karst basin and similar karst basins.

Equity Reform and High-Quality Development of State-Owned Enterprises: Evidence From China in the New Era.

How to improve the development quality of state-owned enterprises is of great significance to the economic and social development in the transition period. And promoting the reform of mixed ownership is an important path for state-owned enterprises to achieve high-quality development. Based on the micro-data of China's A-share listed state-owned companies, the paper explores the impact of mixed ownership reform on the high-quality development of state-owned enterprises. It clarifies the importance and moderation of equity reform and the heterogeneity of impact effects from the theoretical mechanism analysis and empirical test. It also analyzes the reasons of inverted U-shape from the perspective of the transmission mechanism of the internal competition atmosphere and non-state-owned capital speculation motivation. It is found that the relationship between equity reform and state-owned enterprises' high-quality development is inverted U-shaped with multi-dimensional heterogeneity. From the analysis of conduction mechanism, on the one hand, the equity reform can enhance the internal competitive atmosphere, stimulate the vitality of enterprises and improve the development quality for state-owned enterprises. On the other hand, it enhances the speculation motivation of enterprises and slows down the high-quality development process.

A K+-sensitive AND-gate dual-mode probe for simultaneous tumor imaging and malignancy identification.

Although molecular imaging probes have the potential to non-invasively diagnose a tumor, imaging probes that can detect a tumor and simultaneously identify tumor malignancy remain elusive. Here, we demonstrate a potassium ion (K+) sensitive dual-mode nanoprobe (KDMN) for non-invasive tumor imaging and malignancy identification, which operates via a cascaded 'AND' logic gate controlled by inputs of magnetic resonance imaging (MRI) and fluorescence imaging (FI) signals. We encapsulate commercial K+ indicators into the hollow cavities of magnetic mesoporous silica nanoparticles, which are subsequently coated with a K+-selective membrane that exclusively permits the passage of K+ while excluding other cations. The KDMN can readily accumulate in tumors and enhance the MRI contrast after systemic administration. Spatial information of the tumor lesion is thus accessible via MRI and forms the first layer of the 'AND' gate. Meanwhile, the KDMN selectively captures K+ and prevents interference from other cations, triggering a K+-activated FI signal as the second layer of the 'AND' gate in the case of a malignant tumor with a high extracellular K+ level. This dual-mode imaging approach effectively eliminates false positive or negative diagnostic results and allows for non-invasive imaging of tumor malignancy with high sensitivity and accuracy.

New Era of Mapping and Understanding Common Fragile Sites: An Updated Review on Origin of Chromosome Fragility.

Common fragile sites (CFSs) are specific genomic loci prone to forming gaps or breakages upon replication perturbation, which correlate well with chromosomal rearrangement and copy number variation. CFSs have been actively studied due to their important pathophysiological relevance in different diseases such as cancer and neurological disorders. The genetic locations and sequences of CFSs are crucial to understanding the origin of such unstable sites, which require reliable mapping and characterizing approaches. In this review, we will inspect the evolving techniques for CFSs mapping, especially genome-wide mapping and sequencing of CFSs based on current knowledge of CFSs. We will also revisit the well-established hypotheses on the origin of CFSs fragility, incorporating novel findings from the comprehensive analysis of finely mapped CFSs regarding their locations, sequences, and replication/transcription, etc. This review will present the most up-to-date picture of CFSs and, potentially, a new framework for future research of CFSs.

A Sub-Nanostructural Transformable Nanozyme for Tumor Photocatalytic Therapy.

The structural change-mediated catalytic activity regulation plays a significant role in the biological functions of natural enzymes. However, there is virtually no artificial nanozyme reported that can achieve natural enzyme-like stringent spatiotemporal structure-based catalytic activity regulation. Here, we report a sub-nanostructural transformable gold@ceria (STGC-PEG) nanozyme that performs tunable catalytic activities via near-infrared (NIR) light-mediated sub-nanostructural transformation. The gold core in STGC-PEG can generate energetic hot electrons upon NIR irradiation, wherein an internal sub-nanostructural transformation is initiated by the conversion between CeO2 and electron-rich state of CeO2-x, and active oxygen vacancies generation via the hot-electron injection. Interestingly, the sub-nanostructural transformation of STGC-PEG enhances peroxidase-like activity and unprecedentedly activates plasmon-promoted oxidase-like activity, allowing highly efficient low-power NIR light (50 mW cm-2)-activated photocatalytic therapy of tumors. Our atomic-level design and fabrication provide a platform to precisely regulate the catalytic activities of nanozymes via a light-mediated sub-nanostructural transformation, approaching natural enzyme-like activity control in complex living systems.

Exploration of nanozymes in viral diagnosis and therapy.

Nanozymes are nanomaterials with similar catalytic activities to natural enzymes. Compared with natural enzymes, they have numerous advantages, including higher physiochemical stability, versatility, and suitability for mass production. In the past decade, the synthesis of nanozymes and their catalytic mechanisms have advanced beyond the simple replacement of natural enzymes, allowing for fascinating applications in various fields such as biosensing and disease treatment. In particular, the exploration of nanozymes as powerful toolkits in diagnostic viral testing and antiviral therapy has attracted growing attention. It can address the great challenges faced by current natural enzyme-based viral testing technologies, such as high cost and storage difficulties. Therefore, nanozyme can provide a novel nanozyme-based antiviral therapeutic regime with broader availability and generalizability that are keys to fighting a pandemic such as COVID-19. Herein, we provide a timely review of the state-of-the-art nanozymes regarding their catalytic activities, as well as a focused discussion on recent research into the use of nanozymes in viral testing and therapy. The remaining challenges and future perspectives will also be outlined. Ultimately, this review will inform readers of the current knowledge of nanozymes and inspire more innovative studies to push forward the frontier of this field.

Artificially engineered antiferromagnetic nanoprobes for ultra-sensitive histopathological level magnetic resonance imaging.

Histopathological level imaging in a non-invasive manner is important for clinical diagnosis, which has been a tremendous challenge for current imaging modalities. Recent development of ultra-high-field (UHF) magnetic resonance imaging (MRI) represents a large step toward this goal. Nevertheless, there is a lack of proper contrast agents that can provide superior imaging sensitivity at UHF for disease detection, because conventional contrast agents generally induce T2 decaying effects that are too strong and thus limit the imaging performance. Herein, by rationally engineering the size, spin alignment, and magnetic moment of the nanoparticles, we develop an UHF MRI-tailored ultra-sensitive antiferromagnetic nanoparticle probe (AFNP), which possesses exceptionally small magnetisation to minimize T2 decaying effect. Under the applied magnetic field of 9 T with mice dedicated hardware, the nanoprobe exhibits the ultralow r2/r1 value (~1.93), enabling the sensitive detection of microscopic primary tumours (<0.60 mm) and micrometastases (down to 0.20 mm) in mice. The sensitivity and accuracy of AFNP-enhanced UHF MRI are comparable to those of the histopathological examination, enabling the development of non-invasive visualization of previously undetectable biological entities critical to medical diagnosis and therapy.

ARIH1 signaling promotes anti-tumor immunity by targeting PD-L1 for proteasomal degradation.

Cancer expression of PD-L1 suppresses anti-tumor immunity. PD-L1 has emerged as a remarkable therapeutic target. However, the regulation of PD-L1 degradation is not understood. Here, we identify several compounds as inducers of PD-L1 degradation using a high-throughput drug screen. We find EGFR inhibitors promote PD-L1 ubiquitination and proteasomal degradation following GSK3α-mediated phosphorylation of Ser279/Ser283. We identify ARIH1 as the E3 ubiquitin ligase responsible for targeting PD-L1 to degradation. Overexpression of ARIH1 suppresses tumor growth and promotes cytotoxic T cell activation in wild-type, but not in immunocompromised mice, highlighting the role of ARIH1 in anti-tumor immunity. Moreover, combining EGFR inhibitor ES-072 with anti-CTLA4 immunotherapy results in an additive effect on both tumor growth and cytotoxic T cell activation. Our results delineate a mechanism of PD-L1 degradation and cancer escape from immunity via EGFR-GSK3α-ARIH1 signaling and suggest GSK3α and ARIH1 might be potential drug targets to boost anti-tumor immunity and enhance immunotherapies.

A Phosphatase-Mimetic Nano-Stabilizer of Mast Cells for Long-Term Prevention of Allergic Disease.

Allergic diseases are pathological immune responses with significant morbidity, which are closely associated with allergic mediators as released by allergen-stimulated mast cells (MCs). Prophylactic stabilization of MCs is regarded as a practical approach to prevent allergic diseases. However, most of the existing small molecular MC stabilizers exhibit a narrow therapeutic time window, failing to provide long-term prevention of allergic diseases. Herein, ceria nanoparticle (CeNP-) based phosphatase-mimetic nano-stabilizers (PMNSs) with a long-term therapeutic time window are developed for allergic disease prevention. By virtue of the regenerable catalytic hotspots of oxygen vacancies on the surface of CeNPs, PMNSs exhibit sustainable phosphatase-mimetic activity to dephosphorylate phosphoproteins in allergen-stimulated MCs. Consequently, PMNSs constantly modulate intracellular phospho-signaling cascades of MCs to inhibit the degranulation of allergic mediators, which prevents the initiation of allergic mediator-associated pathological responses, eventually providing protection against allergic diseases with a long-term therapeutic time window.

Catalytic activity tunable ceria nanoparticles prevent chemotherapy-induced acute kidney injury without interference with chemotherapeutics.

Acute kidney injury (AKI) is a prevalent and lethal adverse event that severely affects cancer patients receiving chemotherapy. It is correlated with the collateral damage to renal cells caused by reactive oxygen species (ROS). Currently, ROS management is a practical strategy that can reduce the risk of chemotherapy-related AKI, but at the cost of chemotherapeutic efficacy. Herein, we report catalytic activity tunable ceria nanoparticles (CNPs) that can prevent chemotherapy-induced AKI without interference with chemotherapeutic agents. Specifically, in the renal cortex, CNPs exhibit catalytic activity that decomposes hydrogen peroxide, and subsequently regulate the ROS-involved genes by activating the Nrf2/Keap1 signaling pathway. These restore the redox homeostasis for the protection of kidney tubules. Under an acidic tumor microenvironment, CNPs become inert due to the excessive H+ that disrupts the re-exposure of active catalytic sites, allowing a buildup of chemotherapy-mediated ROS generation to kill cancer cells. As ROS-modulating agents, CNPs incorporated with context-dependent catalytic activity, hold a great potential for clinical prevention and treatment of AKI in cancer patients.

A Tauopathy-Homing and Autophagy-Activating Nanoassembly for Specific Clearance of Pathogenic Tau in Alzheimer's Disease.

The hyperphosphorylated and aggregated tau accumulation represents a significant pathological hallmark of tauopathies including Alzheimer's disease (AD), which is highly associated with defective autophagy in neuronal cells. Autophagy-activating strategies demonstrate the therapeutic potential for AD in many studies; however, further development is limited by their low efficacy and serious side effects that result from a lack of selectivity for diseased cells. Herein, we report a tauopathy-homing nanoassembly (THN) with autophagy-activating capacity for AD treatment. Specifically, the THN can bind to hyperphosphorylated and/or aggregated tau and selectively accumulate in cells undergoing tauopathy. The THN further promotes the clearance of pathogenic tau accumulation by stimulating autophagic flux, consequently rescuing neuron viability and cognitive functions in AD rats. This study presents a promising nanotechnology-based strategy for tauopathy-homing and autophagy-mediated specific removal of pathogenic tau in AD.

SETD8C302R Mutation Revealed from Myofibroblastoma-Discordant Monozygotic Twins Leads to p53/p21 Deficit and WEE1 Inhibitor Sensitivity.

High-throughput gene sequencing has identified various genetic variants as the culprits for some common hereditary cancers. However, the heritability of a substantial proportion of cancers remains unexplained, which may result from rare deleterious mutations hidden in a myriad of nonsense genetic variations. This poses a great challenge to the understanding of the pathology and thus the rational design of effective treatments for affected patients. Here, whole genome sequencing is employed in a representative case in which one monozygotic twin is discordant for lung inflammatory myofibroblastoma to disclose rare tumor-related mutations. A missense single nucleotide variation rs61955126 T>C in the lysine methyltransferase SETD8 (accession: NM_020382, SETD8C302R ) is exposed. It is shown that SETD8 is vital for genomic integrity by promoting faithful DNA replication, and its C302R mutation downregulates the p53/p21 pathway. Importantly, the SETD8C302R mutation significantly increases the sensitivity of cancer cells to WEE1 inhibition. Given that WEE1 inhibitors have shown great promise for clinical approval, these results impart a potential therapeutic approach using WEE1 inhibitor for cancer patients carrying the same mutation, and indicate that genome sequencing and genetic functional studies can be integrated into individualized therapies.

A PROTAC peptide induces durable ß-catenin degradation and suppresses Wnt-dependent intestinal cancer.

Aberrant activation of Wnt/ß-catenin signaling has been associated with the onset and progression of many types of tumors and thus ß-catenin represents one attractive intracellular target for cancer therapy. Based on the Axin-derived peptide that binds to ß-catenin, two stapled peptides SAHPA1 and xStAx were reported to enhance or impair Wnt/ß-catenin signaling, respectively. In this study, we designed PROTACs (proteolysis targeting chimeras) by coupling SAHPA1 or xStAx with the VHL ligand to achieve efficient ß-catenin degradation. The obtained xStAx-VHLL sustained ß-catenin degradation and manifested strong inhibition of Wnt signaling in cancer cells and in APC-/- organoids. Furthermore, xStAx-VHLL could effectively restrain tumor formation in BALB/C nude mice, and diminish the existing tumors in APCmin/+ mice. More importantly, xStAx-VHLL could potently inhibit the survival of colorectal cancer patient-derived organoids. These findings suggest that xStAx-VHLL exhibits the ability of cancer prevention and cure, highlighting the potential of ß-catenin degrader PROTACs as a new class of promising anticancer agent.

Genome-wide high-resolution mapping of mitotic DNA synthesis sites and common fragile sites by direct sequencing.

Common fragile sites (CFSs) are genomic loci prone to the formation of breaks or gaps on metaphase chromosomes. They are hotspots for chromosome rearrangements and structural variations, which have been extensively implicated in carcinogenesis, aging, and other pathological processes. Although many CFSs were identified decades ago, a consensus is still lacking for why they are particularly unstable and sensitive to replication perturbations. This is in part due to the lack of high-resolution mapping data for the vast majority of the CFSs, which has hindered mechanistic interrogations. Here, we seek to map human CFSs with high resolution on a genome-wide scale by sequencing the sites of mitotic DNA synthesis (MiDASeq) that are specific for CFSs. We generated a nucleotide-resolution atlas of MiDAS sites (MDSs) that covered most of the known CFSs, and comprehensively analyzed their sequence characteristics and genomic features. Our data on MDSs tallied well with long-standing hypotheses to explain CFS fragility while highlighting the contributions of late replication timing and large transcription units. Notably, the MDSs also encompassed most of the recurrent double-strand break clusters previously identified in mouse neural stem/progenitor cells, thus bridging evolutionarily conserved break points across species. Moreover, MiDAseq provides an important resource that can stimulate future research on CFSs to further unravel the mechanisms and biological relevance underlying these labile genomic regions.

Core-Shell-Satellite Nanomaces as Remotely Controlled Self-Fueling Fenton Reagents for Imaging-Guided Triple-Negative Breast Cancer-Specific Therapy.

Triple-negative breast cancer (TNBC) is highly aggressive and insensitive to conventional targeted therapies, resulting in poor therapeutic outcomes. Recent studies have shown that abnormal iron metabolism is observed in TNBC, suggesting an opportunity for TNBC treatment via the iron-dependent Fenton reaction. Nevertheless, the efficiency of current Fenton reagents is largely restricted by the lack of specificity and low intracellular H2 O2 level of cancer cells. Herein, core-shell-satellite nanomaces (Au @ MSN@IONP) are fabricated, as near-infrared (NIR) light-triggered self-fueling Fenton reagents for the amplified Fenton reaction inside TNBC cells. Specifically, the Au nanorod core can convert NIR light energy into heat to induce massive production of intracellular H2 O2 , thereby the surface-decorated iron oxide nanoparticles (IONP) are being fueled for robust Fenton reaction. By exploiting the vulnerability of iron efflux in TNBC cells, such a self-fueling Fenton reaction leads to highly specific anti-TNBC efficacy with minimal cytotoxicity to normal cells. The PI3K/Akt/FoxO axis, intimately involved in the redox regulation and survival of TNBC, is demonstrated to be inhibited after the treatment. Consequently, precise in vivo orthotopic TNBC ablation is achieved under the guidance of IONP-enhanced magnetic resonance imaging. The results demonstrate the proof-of-concept of NIR-light-triggered self-fueling Fenton reagents against TNBC with low ferroportin levels.