From synthesis to applications of biomolecule-protected luminescent gold nanoclusters.

Gold nanoclusters (AuNCs) are a class of novel luminescent nanomaterials that exhibit unique properties of ultra-small size, featuring strong anti-photo-bleaching ability, substantial Stokes shift, good biocompatibility, and low toxicity. Various biomolecules have been developed as templates or ligands to protect AuNCs with enhanced stability and luminescent properties for biomedical applications. In this review, the synthesis of AuNCs based on biomolecules including amino acids, peptides, proteins and DNA are summarized. Owing to the advantages of biomolecule-protected AuNCs, they have been employed extensively for diverse applications. The biological applications, particularly in bioimaging, biosensing, disease therapy and biocatalysis have been described in detail herein. Finally, current challenges and future potential prospects of bio-templated AuNCs in biological research are briefly discussed.

Improvement of skin wound healing by giant salamander skin mucus gel wrapped with bone marrow mesenchymal stem cells via affecting integrin family molecules.

BACKGROUND: Traditional bandages, gauze, and cotton balls are increasingly insufficient for addressing complex war injuries characterized by severe bleeding and diverse wound conditions. The giant salamander, a species of high medical value, secretes a unique mucus when stimulated, which has potential applications in wound care. MATERIALS: Giant salamander skin mucus gel dressing wrapped with bone marrow mesenchymal stem cells (BMSCs-GSSM-gel) was prepared and validated. Skin wound injury of rabbit and mouse models were established. Hematoxylin and Eosin, Masson's trichrome, and Sirius red staining were performed. The platelet aggregation rate and coagulation items were measured. Transcriptome sequencing was performed to find potential differential expression genes. RESULTS: Preparation and characterization of BMSCs-GSSM-gel were performed, and BMSCs-GSSM-gel particles with a diameter of about 200 nm were obtained. BMSCs-GSSM-gel accelerated wound healing in both rabbit and mouse models. BMSCs-GSSM-gel significantly promoted hemostasis via increasing platelet aggregation rate and fibrinogen, but decreasing activated partial thromboplastin time, thrombin time, and prothrombin time. BMSCs-GSSM-gel treatment significantly impacted several genes associated with cell adhesion, inflammatory response, collagen-containing extracellular matrix, and the positive regulation of cell migration based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Integrin Subunit Beta 4 (ITGB4), Integrin Subunit Alpha 3 (ITGA3), and Laminin Subunit Beta 3 (LAMB3) might be involved in the wound healing process by BMSCs-GSSM-gel. CONCLUSIONS: We proved the BMSCs-GSSM-gel greatly improved the skin wound healing, and it might play a crucial role in the application fields of skin damage repair.

The contributions of vaccination and natural infection to the production of neutralizing antibodies against the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) prototype strain and variants.

OBJECTIVES: To evaluate the neutralizing antibody (NAbs) levels against the SARS-CoV-2 Omicron variants BF.7, BQ.1, BQ.1.1, XBB.1, and XBB.1.5 after vaccination and natural infection. METHODS: The NAbs against the different viral strains of 490 SARS-CoV-2 infected and 187 uninfected individuals in Beijing COVID-19 outbreak during December 2022 to January 2023 were analyzed. RESULTS: In uninfected individuals, limited levels of NAbs were produced against both the prototype and variant strains after two doses vaccine, but significantly increased after three or four doses vaccine. The infected individuals had high NAbs levels against the BF.7, BQ.1, and BQ.1.1 variants and moderate NAbs levels against the XBB.1 and XBB.1.5 variants. The highest NAbs levels were observed after two inoculation doses. The third and fourth doses vaccine did not result in a significant increase the NAbs levels. After the last dose of vaccination, the NAbs levels peaked at 12 months for the prototype and BF.7 and between 6 to 12 months for the BQ.1, BQ.1.1, XBB.1, and XBB.1.5 variants. CONCLUSION: The immune response decreases as the virus mutates. If booster vaccination is considered necessary, it is suggested for at least 6 months after infection.

Long noncoding RNAs underlie multiple domestication traits and leafhopper resistance in soybean.

The origin and functionality of long noncoding RNA (lncRNA) remain poorly understood. Here, we show that multiple quantitative trait loci modulating distinct domestication traits in soybeans are pleiotropic effects of a locus composed of two tandem lncRNA genes. These lncRNA genes, each containing two inverted repeats, originating from coding sequences of the MYB genes, function in wild soybeans by generating clusters of small RNA (sRNA) species that inhibit the expression of their MYB gene relatives through post-transcriptional regulation. By contrast, the expression of lncRNA genes in cultivated soybeans is severely repressed, and, consequently, the corresponding MYB genes are highly expressed, shaping multiple distinct domestication traits as well as leafhopper resistance. The inverted repeats were formed before the divergence of the Glycine genus from the Phaseolus-Vigna lineage and exhibit strong structure-function constraints. This study exemplifies a type of target for selection during plant domestication and identifies mechanisms of lncRNA formation and action.

Pan-cancer analysis reveals IL32 is a potential prognostic and immunotherapeutic biomarker in cancer.

Interleukin 32 (IL32) is a pro-inflammatory cytokine that plays a key role in promoting sterile inflammation by modulating immune responses. However, the role of IL32 in various cancers remains unclear. This research aimed to investigate the correlation between IL32 expression and immunity and visualize its prognostic landscape in pan-cancer. We investigated gene expression, genomic alterations, and survival analysis of IL32 in pan-cancer in numerous databases including TCGA, GTEx, cBioPortal, and GDC databases. Tumor immune cell infiltration was assessed using the CIBERSORT computational method as well as the ESTIMATE method to analyze the correlation of IL32 expression with stromal and immune components. Protein-protein interaction analysis was performed in the STRING and GeneMANIA databases, and gene function enrichment was performed by GO set enrichment analysis. Tumor tissues had higher IL32 expression levels than normal tissues. Elevated IL32 expression was associated with poor OS and prognosis. In addition, tumor stemness, TMB, MSI, and immune checkpoint genes were also associated with IL32 expression. Correlations were observed between IL32 expression and B cell, CD4T cell, CD8T cell, neutrophil, macrophage, and DC infiltration in multiple cancers. GO enrichment analysis showed that IL32 expression was associated with cancer pathways, cytokine-receptor interactions, and NOD-like receptor signaling pathways. These findings suggest that IL32 may serve as a biomarker of cancer immune infiltration and poor prognosis, providing new therapeutic targets for cancer treatment.

Bimetallic Coordination Polymers: Synthesis and Applications in Biosensing and Biomedicine.

Bimetallic coordination polymers (CPs) have two different metal ions as connecting nodes in their polymer structure. The synthesis methods of bimetallic CPs are mainly categorized into the one-pot method and post-synthesis modifications according to various needs. Compared with monometallic CPs, bimetallic CPs have synergistic effects and excellent properties, such as higher gas adsorption rate, more efficient catalytic properties, stronger luminescent properties, and more stable loading platforms, which have been widely applied in the fields of gas adsorption, catalysis, energy storage as well as conversion, and biosensing. In recent years, the study of bimetallic CPs synergized with cancer drugs and functional nanomaterials for the therapy of cancer has increasingly attracted the attention of scientists. This review presents the research progress of bimetallic CPs in biosensing and biomedicine in the last five years and provides a perspective for their future development.

Double counting heart rate - Littmann sign in electrocardiogram.

This report highlights necessity of correctly and quickly identifying Littmann sign. Littmann sign is not common in clinical practice, which is easily overlooked by most physicians, leading to delays in the treatment of hyperkalemia. A 68 year old patient with hyperkalemia was found to have inconsistent heart rate displayed on electrocardiogram monitoring with cardiac auscultation and synchronous electrocardiogram in the early stages of onset. Hyperkalemia was highly suspected by the Littmann sign. After completing arterial blood gas analysis, hyperkalemia was identified and active potassium lowering treatment was immediately initiated. The Littmann syndrome disappeared, and the patient eventually recovered.

Asymmetric double networks mutual teaching for unsupervised person Re-identification.

Unsupervised person re-identification (Re-ID) has always been challenging in computer vision. It has received much attention from researchers because it does not require any labeled information and can be freely deployed to new scenarios. Most unsupervised person Re-ID research studies produce and optimize pseudo-labels by iterative clustering algorithms on a single network. However, these methods are easily affected by noisy labels and feature variations caused by camera shifts, which will limit the optimization of pseudo-labels. In this paper, we propose an Asymmetric Double Networks Mutual Teaching (ADNMT) architecture that uses two asymmetric networks to generate pseudo-labels for each other by clustering, and the pseudo-labels are updated and optimized by alternate training. Specifically, ADNMT contains two asymmetric networks. One network is a multiple granularity network, which extracts pedestrian features of multiple granularity that correspond to numerous classifiers, and the other network is a conventional backbone network, which extracts pedestrian features that correspond to a classifier. Furthermore, because the camera style changes seriously affect the generalization ability of the proposed model, this paper designs Similarity Compensation of Inter-Camera (SCIC) and Similarity Suppression of Intra-Camera (SSIC) according to the camera ID of the pedestrian images to optimize the similarity measure. Extensive experiments on multiple Re-ID benchmark datasets show that our proposed method achieves superior performance compared with the state-of-the-art unsupervised person re-identification methods.

Activation of G protein-coupled receptor 39 alleviates neuropathic pain and chronic inflammation.

Neuropathic pain (NP) is mainly caused by lesions or diseases of the somatosensory nervous system and triggers severe physical burdens to patients. It is claimed that activated microglia-mediated neuroinflammation participates in the development of NP, which is regulated by p38 mitogen-activated protein kinase (MAPK)/nuclear factor-κappa B (NF-κB) p65 signaling. G protein-coupled receptor 39 (GPR39) is a trans-membrane protein involved in the activation of cellular transduction pathways, and TC-G 1008, a GPR39 agonist, is believed to have inhibitory effects on neuroinflammation. Our study will explore the possible alleviatory function of TC-G 1008 on NP in a rat model. GPR39 was found markedly downregulated in the spinal dorsal horn of chronic constriction injury (CCI)-stimulated rats. Rats were treated with CCI, followed by intranasal administration with 7.5 and 15 mg/kg TC-G 1008 at 1, 25, 49, and 73 h postmodeling, respectively. Drastically lowered values of paw withdrawal threshold and paw withdrawal latency, upregulated ionized calcium-binding adapter molecule 1, increased release of inflammatory cytokines, elevated spinal malondialdehyde levels, and reduced spinal glutathione peroxidase levels were observed in CCI-stimulated rats, all of which were markedly alleviated and rescued by TC-G 1008. Furthermore, the levels of p-p38/p38 and p-NF-κB p65 were found signally repressed in the spinal dorsal horn of CCI-stimulated rats, which was notably reversed by TC-G 1008. Collectively, TC-G 1008 markedly alleviated NP and neuroinflammation in CCI-treated rats. Our findings provide an attractive future direction for the treatment of NP.

Photonic instantaneous microwave frequency measurement based on frequency-phase mapping with high precision.

This paper presents an instantaneous microwave frequency measurement scheme based on a frequency-phase mapping technique. In our scheme, a low-frequency (LF) reference signal and two microwave signals with a relative time delay are modulated on the optical carriers via two dual-parallel Mach-Zehnder modulators. The generated electrical signal has the same frequency as that of the LF reference signal, but with a phase shift, which depends on the microwave signal frequency and the time delay. Therefore, a linear frequency-phase mapping function with a high slope is constructed, which improves the accuracy of the whole frequency measurement range. The scheme has a compact structure without an optical filter and polarization devices, which enhances the long-term stability of the system. The simulation shows that our scheme has a 4.1-40 GHz frequency measurement range with errors less than ±0.04 GHz.

Identification and mapping of a recessive allele, dt3, specifying semideterminate stem growth habit in soybean.

KEY MESSAGE: A locus, dt3, modulating semideterminancy in soybean, was discovered by a combination of genome-wide association studies and linkage mapping with multiple distinct biparental populations. Stem growth habit is a key architectural trait in many plants that contributes to plant productivity and environmental adaptation. In soybean, stem growth habit is classified as indeterminate, semideterminate, or determinate, of which semideterminacy is often considered as a counterpart of the "Green Revolution" trait in cereals that significantly increased grain yields. It has been demonstrated that semideterminacy in soybean is modulated by epistatic interaction between two loci, Dt1 on chromosome 19 and Dt2 on chromosome 18, with the latter as a negative regulator of the former. Here, we report the discovery of a third locus, Dt3, modulating soybean stem growth habit, which was delineated to a ~ 196-kb region on chromosome 10 by a combination of allelic and haplotypic analysis of the Dt1 and Dt2 loci in the USDA soybean Germplasm Collection, genome-wide association studies with three subsets of the collection, and linkage mapping with four biparental populations derived from crosses between one of two elite indeterminate cultivars and each of four semideterminate varieties possessing neither Dt2 nor dt1. These four semideterminate varieties are recessive mutants (i.e., dt3/dt3) in the Dt1/Dt1;dt2/dt2 background. As the semideterminacy modulated by the Dt2 allele has unfavorable pleotropic effects such as sensitivity to drought stress, dt3 may be an ideal alternative for use to develop semideterminate cultivars that are more resilient to such an environmental stress. This study enhances our understanding of the genetic factors underlying semideterminacy and enables more accurate marker-assisted selection for stem growth habit in soybean breeding.

Mechanism of ozone alleviation of malignant ascites in hepatocellular carcinoma through the inhibition of neutrophil extracellular traps.

Malignant ascites in hepatocellular carcinoma is usually a sign of advanced disease and poor prognosis and is also thought to be associated with chronic inflammation mediated by neutrophil extracellular trap (NET) networks. Although ozone, a strong oxidant, has significant antibacterial and anti-inflammatory effects, its effectiveness in treating malignant liver ascites is unclear. We first measured the levels of NETs in the peripheral blood of patients with liver cancer and healthy individuals. Next, we constructed the H22 tumor-bearing mouse model and observed the abdominal girth, body weight, survival rate, and survival time in each group; we marked the proteins associated with NETs in mouse intestinal tissues by immunofluorescence; cf-DNA and cytokines in ascites such as: tumor necrosis factor alpha (TNF-α), vascular endothelial growth factor (VEGF), interleukin 6 (IL-6), matrix metalloprotein 9 (MMP-9), and interferon gamma (IFN-γ) levels in ascites were measured by enzyme-linked immunosorbent assay. The expression levels of phosphorylated adenylate-activated protein kinase (P-AMPK) and scavenger receptor-A (SR-A) were detected by immunocytochemistry in the intestinal tissues of each group of mice. We further examined the expression of P-AMPK and SR-A proteins in ascites deposits by Western blotting. The results show, the plasma levels of NETs were higher in patients with hepatocellular carcinoma than in normal subjects (P < 0.01). Abdominal girth and body weight were significantly reduced in the ozone-treated group compared with the model group, while survival and survival time were dose dependently increased (both P < 0.05). NET-associated guanine histone H3 and myeloperoxidase were abundantly expressed at neutrophil aggregates in the intestinal tissues of the model mice, whereas their expression was significantly reduced in the ozone-treated group. The levels of cf-DNA, IL-6, IFN-γ, MMP-9, VEGF, and TNF-α were dose dependently increased in the ascites of H22 tumor-bearing mice in the ozone-treated group compared with the model group (all P < 0.01), while the expression of P-AMPK and SR-A proteins was increased in the ozone-treated group compared with the model group. Ozone showed significant antiperitoneal fluid production properties in H22 tumor-bearing mice, and ozone reduced peritoneal fluid production by activating AMPK and up-regulating SR-A phagocytosis damage-associated molecular patterns to reduce the production of NETs. This suggests that ozone could be used as a new drug for the treatment of malignant ascites in hepatocellular carcinoma.

Tri-comb generation with a dual-ring structure.

By introducing a third measurement comb with different repetition frequencies (Δ f r e p ), the tri-comb spectroscopy technique overcomes the ambiguity problem of the original dual-comb spectroscopy technique and eliminates physical delay stages in multidimensional coherent spectroscopy. Nowadays, tri-comb generation based on three frequency-stabilized comb lasers is overly complicated and costly for many potential applications. Previous research on single-cavity dual-combs inspired research on single-cavity tri-combs. However, the currently reported tri-comb structures cannot achieve independently controllable pulses. This paper shows a dual-ring tri-comb seed-source structure using wavelength-based multiplexing in one of the rings. The wavelength and power of the output pulse are independently controlled by using the dual-ring structure. The Δ f r e p of wavelength multiplexing-based dual-comb output can be tuned by adjusting the intra-ring polarization controller (PC). In the case of single-wavelength mode-locking, the PC can be adjusted to achieve a wavelength tuning range of nearly 20 nm. The tri-comb source could offer an attractive alternative solution as a low-complexity light source for field-deployable multi-comb metrology applications.

Locating Hydrogen Positions for COF-300 by Cryo-3D Electron Diffraction.

Covalent organic frameworks (COFs) have wide-ranging applications, and their host-guest interactions play an essential role in the achievement of COF functions. To investigate these host-guest interactions, it is necessary to locate all atoms, especially hydrogen atoms. However, it is difficult to determine the hydrogen atomic positions in COFs because of the complexities in synthesizing high-quality large single crystals. Three-dimensional electron diffraction (3D ED) has unique advantages for the structural determination of nanocrystals and identification of light atoms. In this study, it was demonstrated for the first time that the hydrogen atoms of a COF, not only on the framework but also on the guest molecule, can be located by 3D ED using continuous precession electron diffraction tomography (cPEDT) under cryogenic conditions. The host-guest interactions were clarified with the location of the hydrogen atoms. These findings provide novel insights into the investigation of COFs.

Albumin use and mortality among intensive care patients with acute heart failure: a retrospective study.

OBJECTIVE: Hypoproteinemia is common in patients with acute heart failure, especially in the intensive care unit (ICU). We assessed short-term mortality in patients with acute heart failure for albumin and nonalbumin users. METHODS: Our study was a retrospective, observational and single-center study. We included patients with acute heart failure from the Medical Information Mart for Intensive Care-IV and compared short-term mortality and length of hospital stay in patients with and without albumin use. We used propensity score matching (PSM) to adjust for confounders, a multivariate Cox proportional hazard regression model, and performed subgroup analysis. RESULTS: We enrolled 1706 patients with acute heart failure (318 albumin users and 1388 nonalbumin users). The 30-day overall mortality rate was 15.1% (258/1706). After PSM, the 30-day overall mortality was 22.9% (67/292) in the nonalbumin group and 13.7% (40/292) in the albumin group. In the Cox regression model, after propensity matching, the albumin use group was associated with a 47% reduction in 30-day overall mortality [hazard ratio (HR) = 0.53, 95% confidence interval (CI): 0.36-0.78, P = 0.001]. In subgroup analysis, the association was more significant in males, patients with heart failure with reduced ejection fraction (HFrEF), and nonsepsis patients. CONCLUSION: In conclusion, our investigation suggests that the use of albumin was associated with lower 30-day mortality in patients with acute heart failure, especially in males, those aged >75 years, those with HFrEF, those with higher N-terminal pro-brain natriuretic peptide levels, and those without sepsis.

The genetic basis of shoot architecture in soybean.

Shoot architecture refers to the three-dimensional body plan of the above ground organs of the plant. The patterning of this body plan results from the tight genetic control of the size and maintenance of meristems, the initiation of axillary growth, and the timing of developmental phase transition. Variation in shoot architecture can result in dramatic differences in plant productivity and/or grain yield due to their effects on light interception, photosynthetic efficiency, response to agronomic inputs, and environmental adaptation. The fine-tuning of shoot architecture has consequently been of great interest to plant breeders, driving the need for deeper understanding of the genes and molecular mechanisms governing these traits. In soybean, the world's most important oil and protein crop, major components of shoot architecture include stem growth habit, plant height, branch angle, branch number, leaf petiole angle, and the size and shape of leaves. Key genes underlying some of these traits have been identified to integrate hormonal, developmental, and environmental signals modulating the growth and orientation of shoot organs. Here we summarize the current knowledge and recent advances in the understanding of the genetic control of these important architectural traits in soybean.

Crystallization of Dimensional Isomers in Covalent Organic Frameworks.

Dimensional isomers, defined in reticular chemistry as frameworks consisting of identical molecular building blocks but extended in two or three dimensions (2D or 3D), are an important type of framework isomers that have never been isolated. Herein, we report the crystallization of dimensional isomers in covalent organic frameworks (COFs) for the first time. By polymerization of the same molecular building blocks at different temperatures, both 2D and 3D COFs were successfully constructed due to the temperature-induced conformational changes of precursors from planar to tetrahedral. In addition, the non-fluorescent 2D COF can be gradually converted into the fluorescent 3D COF by increasing the temperature under solvothermal conditions. Therefore, it is reasonable to crystallize the dimensional isomers of reticular materials by controlling the conformation of molecular building blocks, and more examples can be expected. Since the obtained dimensional isomers show different properties and functions, this work will definitely motivate us to design reticular materials for target applications in the future.

Photonic approach for Doppler-frequency-shift and angle-of-arrival measurement with direction unambiguity and high precision.

A novel, to the best of our knowledge, scheme based on a dual-drive Mach-Zehnder modulator (DDMZM) is proposed for Doppler-frequency-shift (DFS) and angle-of-arrival (AOA) measurement without direction ambiguity. The echo signal from one antenna is coupled with a local oscillator and then fed into the upper RF port of the DDMZM, and the echo signal from the other one is directly fed to its lower RF port. The generated two first-order optical sidebands are separated by an interleaver to form two channels and then detected by two identical low-speed photodiodes, and so both magnitude and orientation of the AOA and DFS can be deduced from the power and frequency of the beating signals. The AOA measurement without direction ambiguity can be achieved by comparing the power of beating signals from two channels. In addition, through operating the DDMZM at different transmission points for different AOA measurement ranges, the range of high-precision AOA measurement can be extended. The system has the low complexity and high stability because only a DDMZM is used. The simulation results demonstrate the measurement of the DFS in the range of 500 kHz with errors <0.05H z and the AOA from -90∘ to +90∘ with error <0.8∘.

One-Stop Extraction and In Situ RT-qPCR for Ultrasensitive Detection of Highly Diluted SARS-CoV-2 in Large-Volume Samples from Aquatic Environments.

Surveillance of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in aquatic environments attracted attention due to its considerable impacts on human health and ecology, especially in countries with poor sanitation standards. Based on a strategy of one-stop extraction and in situ amplification, we developed an ultrasensitive method that uses a polyacrylamide derivative-modified filter disc (PAD-FD), in which highly diluted RNA can be efficiently concentrated onto the filter disc and directly used for amplification. A newly designed spin column with a cup-like filter base facilitated the non-contact transfer of the affinity filter disc from the column to a PCR tube. The limit of detection of the PAD-FD coupled with RT-qPCR is 10 copies/mL. Using 32 suspected SARS-CoV-2 samples, we demonstrated that the detection rate of our method (62.5%, 20/32) was triple the rate of the commercial kit (18.8%, 6/32). Using a PAD-FD, 56.3% (18/32) and 40.6% (13/32) of the 10-fold-dilution samples with river and tap water, respectively, were detected. Even when diluted 100-fold, 28.1% (9/32) and 37.5% (12/32) were still detected in river and tap water, respectively. We believe that the PAD-FD method offers an accurate testing tool for monitoring viral RNA in aquatic environments, contributing to the forewarning of the SARS-CoV-2 outbreak and the breaking of the transmission chain.