ROS-Responsive Fluorescent Sensor Array for Precise Diagnosis of Cancer via pH-Controlled Multicolor Gold Nanoclusters.

Intracellular reactive oxygen species (ROS) are closely associated with cancer cell types. Therefore, ROS-based pattern recognition is a promising strategy for precise diagnosis of cancer, but such a possibility has never been reported yet. Herein, we proposed an ROS-responsive fluorescent sensor array based on pH-controlled histidine-templated gold nanoclusters (AuNCs@His) to distinguish cancer cell types and their proliferation states. In this strategy, three types of AuNCs@His with diverse fluorescence profiles were first synthesized by only adjusting the pH value. Upon the addition of various ROS, fluorescence quenching of three types of AuNCs@His occurred with different degrees, thereby forming unique optical "fingerprints", which were well-clustered into several separated groups without overlap by principal component analysis (PCA). The sensing mechanism was attributable to the oxidation of AuNCs@His by ROS, as revealed by X-ray photoemission spectroscopy, Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy, and electrospray ionization mass spectrometry. Based on the ROS-responsive sensing pattern, cancer cell types were successfully differentiated via PCA with 100% accuracy. Additionally, the proposed sensor array exhibited excellent performance in distinguishing the proliferation states of cancer cells, which was supported by the results of the Ki-67 immunohistochemistry assay. Overall, the ROS-responsive fluorescent sensor array can serve as a promising tool for precise diagnosis of cancer, indicating great potential for clinical application.

Novel HIF-1α Inhibitor AMSP-30m Mitigates the Pathogenic Cellular Behaviors of Hypoxia-Stimulated Fibroblast-Like Synoviocytes and Alleviates Collagen-Induced Arthritis in Rats via Inhibiting Sonic Hedgehog Pathway.

Synovial hypoxia-inducible factor 1α (HIF-1α) is a prospective therapeutic target for rheumatoid arthritis (RA). AMSP-30 m, a novel HIF-1α inhibitor, was reported to have notable anti-arthritic effects in rats with adjuvant-induced arthritis. However, its roles in inhibiting the pathogenic behaviors of fibroblast-like synoviocytes (FLS) and the involved mechanisms remain unknown. Here, AMSP-30 m inhibited proliferation and induced apoptosis in hypoxia-induced RA FLS (MH7A cell line), as evidenced by decreased cell viability, reduced Ki67-positive cells, G0/G1 phase arrest, lowered C-myc and Cyclin D1 protein levels, emergence of apoptotic nuclear fragmentation, raised apoptosis rates, and activation of caspase 3. Furthermore, AMSP-30 m prevented hypoxia-induced increases in pro-inflammatory factor production, MMP-2 activity, migration index, migrated/invasive cells, and actin cytoskeletal rearrangement. In vivo, AMSP-30 m alleviated the severity of rat collagen-induced arthritis (CIA). Mechanically, AMSP-30 m reduced HIF-1α expression and blocked sonic hedgehog (Shh) pathway activation in hypoxia-induced MH7A cells and CIA rat synovium, as shown by declines in pathway-related proteins (Shh, Smo, and Gli-1). Particularly, the combination of Shh pathway inhibitor cyclopamine enhanced AMSP-30 m's inhibitory effects on the pathogenic behaviors of hypoxia-stimulated MH7A cells, whereas the combination of Shh pathway activator SAG canceled AMSP-30 m's therapeutic effects in vitro and in CIA rats, implying a close involvement of Shh pathway inhibition in its anti-arthritic effects. We likewise confirmed AMSP-30 m's anti-proliferative role in hypoxia-induced primary CIA FLS. Totally, AMSP-30 m suppressed hypoxia-induced proliferation, inflammation, migration, and invasion of MH7A cells and ameliorated the severity of rat CIA via inhibiting Shh signaling.

Self-assembled ratiometric sensor for specific detection of hypoxia in living cells based on lanthanide-doped upconversion nanoparticles and gold nanoparticles.

We describes the development of a self-assembled nanoprobe for ratiometric sensing of hypoxia in living cells. The probe, UC-AuNPs, is composed of azo-functionalized upconversion nanoparticles (azo-UCNPs) and gold nanoparticles functionalized withß-cyclodextrin (CD-AuNPs). Under hypoxic conditions, reductases reduce azo derivatives on the UCNPs, leading to detachment of the CD-AuNPs and subsequent fluorescence recovery of the green emission. The ratiometric measurement incorporated into the strategy reduces the impact of external factors and improves sensitivity of the probe. The use of NIR excitation effectively minimizes interference from strong luminescence backgrounds in biosystems. The UC-AuNPs nanoprobe is able to effectively sense and monitor hypoxia conditions in living cells and has the potential to distinguish hypoxia-related diseases from healthy tissue, making it a valuable tool for early clinical diagnosis.

Catalytic probes based on aggregation-induced emission-active Au nanoclusters for visualizing MicroRNA in living cells and in vivo.

Highly sensitive monitoring of cancer-related miRNAs is of great significance for tumor diagnosis. Herein, catalytic probes based on DNA-functionalized Au nanoclusters (AuNCs) were prepared in this work. The aggregation-induced emission-active Au nanoclusters showed an interesting phenomenon of aggregation induced emission (AIE) affected by the aggregation state. Leveraging this property, the AIE-active AuNCs were used to develop catalytic turn-on probes for detecting in vivo cancer-related miRNA based on a hybridization chain reaction (HCR). The target miRNA triggered the HCR and induced aggregation of AIE-active AuNCs, leading to a highly luminescent signal. The catalytic approach demonstrated a remarkable selectivity and a low detection limit in comparison to noncatalytic sensing signals. In addition, the excellent delivery the ability of MnO2 carrier made it possible to use the probes for intracellular imaging and in vivo imaging. Effective in situ visualization of miR-21 was achieved not only in living cells but also in tumors in living animals. This approach potentially offers a novel method for obtaining information for tumor diagnosis via highly sensitive cancer-related miRNA imaging in vivo.

TRIM5α recruits HDAC1 to p50 and Sp1 and promotes H3K9 deacetylation at the HIV-1 LTR.

Tripartite motif-containing protein 5α (TRIM5α) is generally known to block the postentry events of HIV-1. Here, we report an uncharacterized role for TRIM5α in the maintenance of viral latency. Knockdown of TRIM5α potentiates the transcription of HIV-1 in multiple latency models, which is reversed by shRNA-resistant TRIM5α. TRIM5α suppresses TNFα-activated HIV-1 LTR-driven as well as NF-κB- and Sp1-driven gene expression, with the RING and B-box 2 domains being the essential determinants. Mechanistically, TRIM5α binds to and enhances the recruitment of histone deacetylase 1 (HDAC1) to NF-κB p50 and Sp1. ChIP‒qPCR analyses further reveal that the association of TRIM5α with HIV-1 LTR induces HDAC1 recruitment and local H3K9 deacetylation. Conserved suppression effects of TRIM5α orthologs from multiple species on both HIV-1 and endo-retroelement HERV-K LTR activities have also been demonstrated. These findings provide new insights into the molecular mechanisms by which proviral latency is initially established and activatable proviruses are resilenced by histone deacetylase recruitment.

TRIM28 negatively regulates the RLR signaling pathway by targeting MAVS for degradation via K48-linked polyubiquitination.

Mitochondrial antiviral signaling (MAVS) protein is a core signaling adapter in the retinoid acid-inducible gene-I-like receptor (RLR) signaling pathway that recruits downstream signaling factors, ultimately leading to the activation of type Ⅰ interferons. However, the mechanisms that modulate the RLR signaling pathway by manipulating MAVS are not fully understood. Previous studies suggested that tripartite motif 28 (TRIM28) participates in regulating innate immune signaling pathways by inhibiting the expression of immune-related genes at the transcriptional level. In this study, we characterized TRIM28 as a negative regulator of the RLR signaling pathway in a MAVS-dependent manner. Overexpression of TRIM28 inhibited the MAVS-induced production of type Ⅰ interferons and proinflammatory cytokines, while knocking down TRIM28 exerted the opposite effect. Mechanistically, TRIM28 targeted MAVS for proteasome-mediated degradation via K48-linked polyubiquitination. The RING domain of TRIM28, especially the cysteine residues at positions 65 and 68, was critical for the suppressive effect of TRIM28 on MAVS-mediated RLR signaling, while each of the C-terminal domains of TRIM28 contributed to its interaction with MAVS. Further investigation revealed that TRIM28 transferred ubiquitin chains to the K7, K10, K371, K420, and K500 residues of MAVS. Together, our results reveal a previously uncharacterized mechanism involving TRIM28 in fine-tuning innate immune responses and provide new insights into the mechanisms by which MAVS is regulated, which contribute to the understanding of the molecular mechanisms underlying immune homeostasis maintenance.

Papain-like protease of SARS-CoV-2 inhibits RLR signaling in a deubiquitination-dependent and deubiquitination-independent manner.

The newly emerged severe acute respiratory syndrome (SARS) coronavirus-2 (SARS-CoV-2) can result in dysregulated interferon (IFN) responses that contribute to disease severity. The papain-like protease of SARS-CoV-2 (SCoV2-PLpro) has been previously reported to attenuate IFN responses, but the underlying mechanism is not fully understood. In this study, we found that SCoV2-PLpro potently suppressed IFN production and signaling induced by Sendai virus as well as RIG-I-like receptor (RLR) signaling pathway components, including RIG-I, MAVS, TBK1, TRAF3, TRAF6, and IRF3. SCoV2-PLpro exhibited different specificity and efficiency than SARS-CoV PLpro, with the former exerting a greater inhibitory effect on the RIG-I- and TRAF3-mediated IFN response but a weaker effect on the MAVS-mediated IFN response. Furthermore, we showed that SCoV2-PLpro significantly reduced K63-ubiquitination of RIG-I, MAVS, TBK1, TRAF3, TRAF6, and IRF3 and K48-ubiquitination of IκBα, which are known critical for the innate immune signal transduction. The deubiquitinating (DUB) activity of SCoV2-PLpro required a catalytic residue cysteine 111 (C111) but not the UBL domain. Notably, by utilizing the DUB-defective C111 mutant, we demonstrated that SCoV2-PLpro targeted RLR signaling pathway regulators via deubiquitination-dependent and -independent mechanisms, with the inhibitory activities of RIG-I and TBK1 correlating with DUB function, whereas the antagonism effects on MAVS, TRAF3, TRAF6, and IRF3 independent on DUB activity. Overall, our results reveal that SCoV2-PLpro evolves differential IFN antagonism activity from SCoV1-PLpro and it targets multiple key RLR signaling pathway components via various mechanisms, providing insights into SARS-CoV-2 pathogenesis and clues for developing antiviral therapies for COVID-19.

Nucleic acid-driven aggregation-induced emission of Au nanoclusters for visualizing telomerase activity in living cells and in vivo.

Visual monitoring of telomerase activity in living cancer cells and in vivo is essential for clinical diagnosis and treatment. However, most detection methods were performed in vitro due to the difficulty of probes entering cells and the interferences from complex biological environments. Herein, we developed a novel probe based on Au nanoclusters (AuNCs) with a nucleic acid-driven aggregation-induced emission (AIE) property for the first time. The probe was applied for detection of telomerase with high sensitivity. Importantly, the probe could achieve telomerase imaging in living cells and in solid tumor tissue in vivo. The study provided a specific connection fashion of metal nanoclusters for AIE generation. It holds great potential for the development of AIE-active metal nanoclusters as a diagnostic tool for disease detection in vitro as well as in vivo.

[Sources, Distribution, and Fluxes of Major and Trace Elements in the Yangtze River].

Surface water samples were collected from 20 sampling sites in the main stream and its major tributaries of the Yangtze River from April to May 2017. The concentrations of dissolved trace and major elements were analyzed to determine the spatial variation, source identification, and riverine fluxes using various multivariate statistical techniques, including correlation analysis, principal component analysis (PCA), and cluster analysis (CA) with the goal of determining the influence of natural factors and human activities, including the operation of the Three Gorges Dam on the distribution and loading of major and trace elements in the Yangtze River water environment. Spatial distribution results showed that Cu, Zn, Pb, Cd, and As were the major elements affected by human activities in the Yangtze River, and their concentrations downstream were significantly higher than those in the middle and upper reaches (P<0.05). All elements had fairly high concentration values in both channels of the Yangtze River mainstream in Chongqing city and Hanjiang River in Wuhan city, which were mainly related to the enhanced human activities. However, the low concentrations of multi-elements in the reach of the Yangtze River in Yichang were largely caused by the retention effect of Three Gorges Project on element transport, which decreased the riverine loadings of multi-elements. Principal component analysis (PCA) indicated that Na, Mg, K, Ca, Fe, Mn, Co, Ni, Mo, Cr, and V were mainly associated with the weathering and erosion of various rocks and minerals in the river basin. And Cu, Zn, and Pb were mainly affected by enhanced human activities, such as industrial wastewater, metal smelting, and mineral mining, whereas Cd and As were mainly related to agricultural activities. The spatial distribution of trace and major elements showed that concentrations of some elements in the Yangtze River channels were enhanced by human activities. Generally, the heavy metal pollution in the Yangtze River Basin was lower than that in other rivers of the world. However, the annual fluxes of Cu, Zn, Pb, Cd, and As could have far-reaching ecological effects on the Yangtze River estuary and offshore ecological environment.

Aggregation-induced emission-active Au nanoclusters for ratiometric sensing and bioimaging of highly reactive oxygen species.

We prepared a nanoprobe through self-assembly of gold nanoclusters (AuNCs) and using FITC-modified hyaluronic acid (HA) for ratiometric sensing of highly reactive oxygen species (hROS). Taking advantage of the aggregation-induced emission (AIE) properties of the self-assembled AuNCs, hROS-responsive cleavage of HA, and the ratiometric signal change of dual-emission, the nanoprobe exhibited excellent performance in imaging hROS in living cells.

DNA-MnO2 nanosheets as washing- and label-free platform for array-based differentiation of cell types.

Accurate and facile differentiation of cell types is essential for accurate diagnosis and therapy of diseases. However, it remains challenging due to low specificity, requirement of sophisticated instruments, and tedious operation steps. Herein, a simple, washing- and label-free chemical tongue was constructed for differentiation of cell types. In the array-based sensing platform, DNA-ligand ensembles adsorbed on the surface of MnO2 nanosheets were used as sensing probes. Instead of aptamers from cell-SELEX, the randomly designed DNA strands were used, offering versatile interactions with cells. The property that MnO2 nanosheets can be degraded by intracellular glutathione makes the platform avoid the washing step. Eight types of cell lines were distinguished from each other after the data were treated with principal component analysis (PCA). In addition, a 95% of identification accuracy for the randomly selected unknown samples was achieved. The strategy shows an excellent performance not only in distinguishing cell lines but also in the identification of unknown cell samples.

Nanozyme as Artificial Receptor with Multiple Readouts for Pattern Recognition.

Nanozymes have been widely used for the construction of colorimetric sensors. However, the simultaneous discrimination of multiple targets using nanozymes is still a challenge. In this work, we construct a multiple-readout system for pattern recognition of proteins using nanozyme. Graphitic carbon nitride (g-C3N4) nanosheets, which possess peroxidase-like activity, are chosen as the single sensing receptor. The catalytic activity of g-C3N4 can be changed to different degrees owing to the different interactions between g-C3N4 and proteins. By choosing different combinations of absorbance intensities at various time points, multichannel information can be extracted from a single material for pattern recognition. The platform avoids the synthesis of multiplex sensing receptors and the requirement of sophisticated instruments, leading to lower cost and time consumption. The study provides a new method for the construction of feasible, convenient, and flexibly nanozyme-based sensing arrays.

An intelligent 1:2 demultiplexer as an intracellular theranostic device based on DNA/Ag cluster-gated nanovehicles.

The logic device demultiplexer can convey a single input signal into one of multiple output channels. The choice of the output channel is controlled by a selector. Several molecules and biomolecules have been used to mimic the function of a demultiplexer. However, the practical application of logic devices still remains a big challenge. Herein, we design and construct an intelligent 1:2 demultiplexer as a theranostic device based on azobenzene (azo)-modified and DNA/Ag cluster-gated nanovehicles. The configuration of azo and the conformation of the DNA ensemble can be regulated by light irradiation and pH, respectively. The demultiplexer which uses light as the input and acid as the selector can emit red fluorescence or a release drug under different conditions. Depending on different cells, the intelligent logic device can select the mode of cellular imaging in healthy cells or tumor therapy in tumor cells. The study incorporates the logic gate with the theranostic device, paving the way for tangible applications of logic gates in the future.

A bifunctional nanomodulator for boosting CpG-mediated cancer immunotherapy.

Unmethylated cytosine-phosphate-guanine (CpG) oligonucleotides (ODNs) possess high immunostimulatory activity and represent attractive tools for cancer treatment. However, their success in eliminating large solid tumors was hampered by the immunosuppressive tumor microenvironment. Herein, we report that the design of a novel MnO2-CpG-silver nanoclusters (AgNCs)-doxorubicin (DOX) conjugate for enhanced cancer immunotherapy, in which MnO2 nanosheets function as unique supports to integrate the chemotherapy drug DOX and the immunotherapeutic agent CpG-AgNCs. Importantly, DOX could be conjugated with MnO2 nanosheets through π-π interactions to serve as a bifunctional modulator of the tumor microenvironment to activate a tumor-specific immune response by inducing immunogenic cell death, and reverse the immunosuppressive tumor microenvironment via abrogating the immune-suppressive activity of regulatory T cells, both of which would greatly improve the immune response of CpG-AgNCs. In this way, the T-cell immune responses of CpG-AgNCs which are linked to MnO2 nanosheets were significantly enhanced and could exhibit remarkable antitumor activity against large solid tumors. Our study may guide the rational design of immunotherapeutic boosters for improving cancer treatment.

A DNA-Based Label-Free Artificial Tongue for Pattern Recognition of Metal Ions.

An array-based sensing method offers several advantages for detecting various analytes. DNA molecules as sensor elements have attracted considerable interest owing to their unique properties. Here, a label-free sensor array using DNA and commercially available dyes to differentiate metal ions is reported. Based on the different interactions between dye-bound DNA and metal ions, the fluorescence intensities of the sensor elements are changed to different degrees. In this way, fourteen metal ions can be efficiently distinguished by principal component analysis (PCA) and hierarchical cluster analysis (HCA). A highly sensitive discrimination of metal ions with 92.8 % identification accuracy can be achieved. The present work provides a simple and convenient method for the construction of a DNA-based sensor array.

Hyaluronic Acid-Templated Ag Nanoparticles/Graphene Oxide Composites for Synergistic Therapy of Bacteria Infection.

Developing methods of decreasing the harm to cell and increasing the antibacterial efficiency is becoming a potential topic of medical treatments. We demonstrated a hyaluronidase-triggered photothermal platform for killing bacteria based on silver nanoparticles (AgNPs) and graphene oxide (GO). The property of the hyaluronidase (HAase)-triggered release provided excellent antibacterial activity against Staphylococcus aureus. Upon illumination of NIR light, the GO-based nanomaterials locally raised the temperature, resulting in high mortality of bacteria. The HAase-triggered AgNPs releasing approach for antibacterial allows AgNPs to be protected by hyaluronic acid (HA) template without affecting mammalian cells. The nanocomposites provided antibacterial activity against S. aureus while showing low toxicity to mammal cells. In addition, the GO-HA-AgNPs are prepared for in vivo experiments and show excellent antibacterial property in wound disinfection model.

[Sedimentary Phosphorus Speciation in the Coastal Hypoxic Area of Changjiang Estuary and Its Environmental Significance].

Phosphorus (P) is a potential limiting nutrient in Changjiang Estuary. Sedimentary P preservation and regeneration play an important role in indicating regional environmental changes and buffering P limitation in the water column. A series of coring experiments was implemented in the hypoxic area of Changjiang Estuary to explore sedimentary P speciation and distribution and their environmental significance. The results showed that the contents and distributions of P in the cores were largely influenced by terrestrial loading, and Detr-P was the dominant P form in the sediments, followed by Org-P, Fe-P, and Auth-P, whereas Exch-P was the minor phase of Tot-P (<5%). Auth-P was predominantly yielded by Org-P and Fe-P transformations. P preservation in Changjiang Estuary was significantly related to terrestrial inputs and environmental changes in the water column. P speciation in cores tracked the regional environmental changes effectively. Distribution of reactive P in the hypoxic area was significantly different from that in the oxic area, with fairly high C/P ratios. The benthic diffusive flux of DRP in the study area ranged from 0.90 to 1.13 µmol·(cm2·a)-1. Tot-P burial efficiency (PBE) was higher than 70% and the PBE for Detr-P was nearly 100%, whereas the PBEs for Fe-P and Org-P were 38% and 26%, respectively. Auth-P was the dominant fraction of reactive P preserved in the sediments, and about 51% of Auth-P originated from Fe-P and Org-P transformations. The PBE in the hypoxia area of Changjiang Estuary was fairly lower than that in the continental shelf of the East China Sea. Hypoxia leads to a decrease in the PBE, which would have long-term influence on ecological environmental problems, especially eutrophification. Changes in terrestrial inputs played a key role in P composition in the sediments; the P loads of Changjiang River coupled with primary production and hypoxia greatly affected the P cycling in the Estuary.

Advance of microRNAs for Spine Cord Injury (review) / 中国康复理论与实践

Spine cord injury is a kind of severe central nervous system trauma causing motion and sensation dysfunction. Treatment fo-cuses on controlling secondary injury cascade and improving regeneration which are heavily regulated by microRNAs (miRNAs). This re-view discussed the effect of miRNAs with different subtypes on spine cord injury, and investigated their potential roles as therapeutic agents in the personalized treatment of patients with spine cord injury.

Advance of microRNAs for Spine Cord Injury (review) / 中国康复理论与实践

Spine cord injury is a kind of severe central nervous system trauma causing motion and sensation dysfunction. Treatment fo-cuses on controlling secondary injury cascade and improving regeneration which are heavily regulated by microRNAs (miRNAs). This re-view discussed the effect of miRNAs with different subtypes on spine cord injury, and investigated their potential roles as therapeutic agents in the personalized treatment of patients with spine cord injury.

Development of a Lateral Flow Immunoassay for the Rapid Diagnosis of Invasive Candidiasis.

Early and accurate diagnosis of invasive candidiasis (IC) is very important. In this study, a lateral flow immunoassay (LFIA) was developed to detect antibody against Candida albicans enolase (Eno). Colloidal gold particle labeled mouse anti human IgG (1.0 mg/L) was used as the detector reagent. Recombinant enolase (rEno, 1.0 mg/L) and goat anti IgG (1.0 mg/L) were immobilized in test and control lines, respectively, of a nitrocellulose membrane, acting as the capture reagents. The LFIA was used to detect anti Eno in 38 sera from clinically proven IC patients, as well as in 50 healthy control subjects. Compared with an indirect ELISA designed as a reference test, the specificity and sensitivity of the LFIA were 98.2 and 84.8%, respectively. Excellent agreement between the results obtained by ELISA and the LFIA (κ = 0.851) was observed in this study. In addition, the agreement between the blood culture results and LFIA test is strong (κ = 0.658). The data presented in the study indicate that the LFIA test is a suitable tool for the serological surveillance of IC in the field or in poorly equipped laboratories.