Identification of key genes related to immune cells in patients with gram-negative sepsis based on weighted gene co-expression network analysis.

Background: Gram-negative sepsis is closely related to the immune response, involving collaborative efforts of different immune cells. However, the mechanisms underlying immune cell regulation in gram-negative sepsis remain unclear. Therefore, this study investigated the potential regulatory mechanisms and identified the key genes related to immune cells in gram-negative sepsis. Methods: The RNA-sequencing data for gram-negative sepsis samples and normal samples were collected from the Gene Expression Omnibus (GEO) dataset GSE9960. CIBERSORT was performed to analyze the proportion of 22 types of immune cells in gram-negative sepsis and normal samples. Weighted gene co-expression network analysis (WGCNA) was used to determine the networks that are associated with the differentially distributed immune cells in the two groups. Differentially expressed genes were identified using the limma package. The least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) algorithms were applied to ascertain hub gene signatures. The gene interaction network of hub gene signatures was determined by ingenuity pathway analysis. Furthermore, the expression levels of the key genes were verified using quantitative real-time polymerase chain reaction (qRT-PCR). Results: CIBERSORT analysis showed that the proportions of plasma cells, resting CD4+ memory T cells, M1 macrophages, and eosinophils were significantly different between gram-negative sepsis and normal samples. WGCNA identified 1,100 genes in the most relevant modules associated with these immune cells. In addition, 87 differentially expressed genes were identified. By overlapping the genes found in the WGCNA and the differentially expressed genes, a total of 46 genes related to immune cells were identified. Integrative analysis of LASSO and SVM-RFE identified NLR family CARD domain-containing 4 (NLRC4) and ral guanine nucleotide dissociation stimulator like 4 (RGL4) as key gene signatures related to immune cells in gram-negative sepsis. The qRT-PCR results demonstrated that both NLRC4 and RGL4 were upregulated in peripheral blood mononuclear cells (PBMCs) from patients with sepsis. Conclusions: This investigation provides novel insights into the molecular mechanisms of immune cells involved in the pathogenesis of gram-negative sepsis. NLRC4 and RGL4 were identified as key gene signatures related to immune cells and may act as potential diagnostic biomarkers for gram-negative sepsis.

Impaired Fanconi anemia pathway causes DNA hypomethylation in human angiosarcomas.

Angiosarcomas (AS) is a rare soft tissue sarcomas with poor treatment options and a dismal prognosis. The abnormal DNA methylation pattern has been determined as the certain clinical relevance with different angiosarcoma subtypes. However, the profound mechanism is not clear. In present study, we studied thirty-six AS with or without chronic lymphedema, and reported that DNA damage was an important factor causing DNA methylation abnormality. Furthermore, we determined that the impaired Fanconi anemia (FA) pathway contributed to severe DNA damage in AS with chronic lymphedema. We also observed that the activated FANCD2 could facilitate DNMT1 recruitment on genomic DNA. Our study uncovers a novel regulatory mechanism of FA pathway on DNA methylation, and is a benefit to advanced understanding the pathogenesis of AS, as well as providing the potential therapeutic targets for AS treatment.

pH-Activatable Organic Nanoparticles for Efficient Low-Temperature Photothermal Therapy of Ocular Bacterial Infection.

Low-temperature photothermal therapy (PTT) systems constructed by integrating organic photothermal agents with other bactericidal components that initiate bacterial apoptosis at low hyperthermia possess a promising prospect. However, these multicomponent low-temperature PTT nanoplatforms have drawbacks in terms of the tedious construction process, suboptimal synergy effect of diverse antibacterial therapies, and high laser dose needed, compromising their biosafety in ocular bacterial infection treatment. Herein, a mild PTT nanotherapeutic platform is formulated via the self-assembly of a pH-responsive phenothiazinium dye. These organic nanoparticles with photothermal conversion efficiency up to 84.5% necessitate only an ultralow light dose of 36 J/cm2 to achieve efficient low-temperature photothermal bacterial inhibition at pH 5.5 under 650 nm laser irradiation. In addition, this intelligent mild photothermal nanoplatform undergoes negative to positive charge reversion in acid biofilms, exhibiting good penetration and highly efficient elimination of drug-resistant E. coli biofilms under photoirradiation. Further in vivo animal tests demonstrated efficient bacterial elimination and inflammatory mitigation as well as superior biocompatibility and biosafety of the photothermal nanoparticles in ocular bacterial infection treatment. Overall, this efficient single-component mild PTT system featuring simple construction processes holds great potential for wide application and clinical transformation.

Paper-Based Ratiometric Fluorescence Analytical Devices towards Point-of-Care Testing of Human Serum Albumin.

Monitoring of human serum albumin (HSA) in a point-of-care fashion is urgently needed in particular for elderly or chronically ill patients. Herein, a dual-state emissive chalcone probe having the feature of aggregation-induced emission was designed and synthesized. The concentration of HSA can be evaluated by the ratios of emission from probes in aggregated and monomeric state, which gives a visually discernible red-to-green color change. A simple, portable paper-based analytical device have been fabricated by integration of the recognition probe in the detection pad and employed for HSA test using the whole blood samples. This paper-based assay shows the analytical capability comparable to the standard testing methods but is in a point-of-care fashion, providing a promising tool for at-home HSA detection and HSA-related disease diagnosis.

A flavonoid-based fluorescent probe enables the accurate quantification of human serum albumin by minimizing the interference from blood lipids.

We herein provide a simple design strategy to improve the sensing specificity towards human serum albumin by incorporating a nitrobenzene quencher into a traditional polarity-sensitive probe in responding to the interference from blood lipids.

A flavonoid-based fluorescent test strip for sensitive and selective detection of a gaseous nerve agent simulant.

Developing fluorescent sensors with ability of monitoring gaseous nerve agents in a sensitive and selective manner is of great importance due to the extreme toxicity and volatility of organophosphorus nerve agents. Herein we reported a novel oxime-modified flavonoid sensor and carefully investigated its sensing behavior towards nerve agent simulants, diethylchlorophosphate (DCP). In the presence of DCP, a remarkable fluorescence enhancement accompanied with emission color change could be observed by naked eyes in solution. The response time was less than 90 s and LOD value was calculated as 0.78 µmol/L in solution. The sensing mechanism could be ascribed to the specific reaction between halophosphate and hydroxyl group of oxime. Furthermore, sensor strips have been successfully constructed by using PEG as matrix with a simple preparation process, and also achieved the sensitive and selective detection of DCP vapor. These results in this study may provide important references for further design of dye-based sensor strips for detection of nerve agents both in solution and gas phase.

Reactive oxygen species, antioxidant enzyme activity, and gene expression patterns in a pair of nearly isogenic lines of nicosulfuron-exposed waxy maize (Zea mays L.).

Nicosulfuron is a post-emergence herbicide used for weed control in maize fields (Zea mays L.). Here, the pair of nearly isogenic inbred lines SN509-R (nicosulfuron resistant) and SN509-S (nicosulfuron sensitive) was used to study the effect of nicosulfuron on growth, oxidative stress, and the activity and gene expression of antioxidant enzymes in waxy maize seedlings. Nicosulfuron treatment was applied at the five-leaf stage and water treatment was used as control. After nicosulfuron treatment, the death of SN509-S might be associated with increased oxidative stress. Compared with SN509-R, higher O2·- and H2O2 accumulations were observed in SN509-S, which can severely damage lipids and proteins, thus reducing membrane stability. The effects were exacerbated with extended exposure time. Both O2·- and H2O2 detoxification is regulated by enzymes. After nicosulfuron treatment, superoxide dismutase (SOD), catalase, ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), and glutathione-S-transferase (GST) of SN509-S were significantly lower than those of SN509-R. Compared to SN509-R, ascorbate content (AA), glutathione (GSH) content, GSH to glutathione disulfide ratios, and AA to dehydroascorbate ratios significantly declined with increasing exposure time in SN509-S. Compared to SN509-S, nicosulfuron treatment increased the transcript levels of most of the APX genes except for APX1, and in contrast to Gst1, upregulated the transcription of sod9, MDHAR, DHAR, and GR genes in SN509-R. These results suggest that on a transcription level and in accordance with their responses, detoxifying enzymes play a vital role in the O2·- and H2O2 detoxification of maize seedlings under nicosulfuron exposure.

Near-Infrared Light-Activated Photochemical Internalization of Reduction-Responsive Polyprodrug Vesicles for Synergistic Photodynamic Therapy and Chemotherapy.

The use of intracellular reductive microenvironment to control the release of therapeutic payloads has emerged as a popular approach to design and fabricate intelligent nanocarriers. However, these reduction-responsive nanocarriers are generally trapped within endolysosomes after internalization and are subjected to unwanted disintegration, remarkably compromising the therapeutic performance. Herein, amphiphilic polyprodrugs of poly(N,N-dimethylacrylamide-co-EoS)-b-PCPTM were synthesized via sequential reversible addition-fragmentation chain transfer (RAFT) polymerization, where EoS and CPTM are Eosin Y- and camptothecin (CPT)-based monomers, respectively. An oil-in-water (O/W) emulsion method was applied to self-assemble the amphiphilic polyprodrugs into hybrid vesicles in the presence of hydrophobic oleic acid (OA)-stabilized upconversion nanoparticles (UCNPs, NaYF4:Yb/Er), rendering it possible to activate the EoS photosensitizer under a near-infrared (NIR) laser irradiation with the generation of singlet oxygen (1O2) through the energy transfer between UCNPs and EoS moieties. Notably, the in situ generated singlet oxygen (1O2) can not only exert its photodynamic therapy (PDT) effect but also disrupt the membranes of endolysosomes and thus facilitate the endosomal escape of internalized nanocarriers (i.e., photochemical internalization (PCI)). Cell experiments revealed that the hybrid vesicles could be facilely taken up by endocytosis. Although the internalized hybrid vesicles were initially trapped within endolysosomes, a remarkable endosomal escape into the cytoplasm was observed under 980 nm laser irradiation as a result of the PCI effect of 1O2. The escaped hybrid vesicles subsequently underwent GSH-triggered CPT release in the cytosol, thereby activating the chemotherapy process. The integration of PDT module into the design of reduction-responsive nanocarriers provides a feasible approach to enhance the therapeutic performance.