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Objective·To construct mice with conditional knockout of Stat3 gene in microglia based on the Cre-Loxp system and validate their knockout efficiency.Methods·Cx3cr1creERT2 and Stat3fl/fl genotypic mice were bred for conditional knockout mice (CKO) and Wild Type mice (WT). The mouse genotypes were determined by extracting DNA from mouse tissues through Polymerase Chain Reaction (PCR) combined with the amplification results of cre and flox primers. Stat3 knockdown was induced by intraperitoneal injection of tamoxifen in the CKO and WT mice at 6 weeks of age. The CKO mice (n=4) and WT mice (n=4) were randomly selected for the detection. After two weeks of observation, microglia cells were sorted out by Magnetic Activated Cell Sorting (MACS). Real-time PCR (RT-PCR) was used to detect gene knockout efficiency at the gene level. The expression of STAT3 in microglia was observed by brain immunofluorescence staining. The expression rate of STAT3 in microglia was detected by flow cytometry. The expression rate of STAT3 in macrophages of the spleen was detected by flow cytometry. The condition of neuronal cells was examined by Nissl staining. The condition of the microglia in the cortex and hippocampus was observed by brain immunofluorescence staining. The phenotype of the microglia was detected by flow cytometry.Results·The CKO mice and WT mice were successfully bred. MACS boosted the proportion of microglia in brain cells from 10% to 85%. RT-PCR results showed that mRNA levels of Stat3 were down-regulated in microglia of CKO mice, compared with the WT mice (P=0.001). The relative mRNA expression of Stat3 in microglia of the CKO mice was 0.331 7±0.041 4. Immunofluorescence staining of brain tissues showed that the fluorescence intensity of STAT3 in microglia of the CKO mice was weaker than that of the WT mice. Flow cytometry of brain tissues showed that the STAT3-positive cells in microglia of the WT mice was (85.30±5.69)% and the CKO mice was (39.70±3.88)%. STAT3 expression was decreased in microglia of the CKO mice (P=0.001). Flow cytometry of spleen tissues showed that there was no statistical difference in the percentage of STAT3-positive cells in splenic macrophages between the CKO and WT mice (P>0.05). Nissl staining showed that there were no significant differences between the neuronal cells of the CKO mice and WT mice. Immunofluorescencestaining of brain tissues showed that there was no significant difference in the shape of microglia between the CKO mice and WT mice. Flow cytometry showed that the phenotype of microglia in the CKO mice was not remarkably different from that of the WT mice.Conclusion·We successfully construct the STAT3 gene conditional knockout mice from microglia, which provides the foundation for subsequent related studies.

Objective support helped FSWs in entertainment venues their behavior to HPV vaccination and to maintain their physical and mental health. [ABSTRACT FROM AUTHOR]

AimTo investigate cyclo (Arg-Gly-Asp-D-Phe-Lys) peptide (RGD)-modified PEGylated dendrimer-entrapped gold nanoparticles (PEGylated Au DENPs-RGD) for targeted computed tomography (CT) imaging of breast carcinomas.Materials & methodsPEGylated Au DENPs-RGD were synthesized and characterized. Then, the PEGylated Au DENPs-RGD for targeted CT imaging were investigated using the MDA-MB-435 cell line, an integrin-rich breast carcinoma cells, and mice with MDA-MB-435 xenograft tumors. Finally, silver enhancement staining and integrin αvβ3 immunohistochemistry of the tumors were performed.ResultsThe synthesized PEGylated Au DENPs-RGD were spherical, water dispersible and biocompatible nanoprobes with a gold nanoparticle core size of 2.8 nm. Due to the presence of the Au nanoparticles, the PEGylated Au DENPs-RGD displayed a higher x-ray attenuation intensity than Omnipaque at the same Au or I concentrations. The conjugated RGD ligand can specifically identify and target overexpressed integrin receptors on MDA-MB-435 cells. After intravenous injection, these nanoprobes accumulated in the targeted area of mice with MDA-MB-435 xenograft tumors, which enabled the tumor to be detected by CT imaging. The histological results confirmed the imaging results.ConclusionThe PEGylated Au DENPs-RGD can be used as targeted nanoprobes with good biocompatibility for targeted CT imaging and diagnosis of integrin-positive tumors.

BACKGROUND: Enterococcus faecalis biofilm was frequently found on the failed treated root canal wall, which survived by resisting disinfectant during endodontic treatment.Many researches have been conducted to explore the mechanisms of persistence of this pathogen in unfavorable conditions. However, no comprehensive proteomics studies have been conducted to investigate stress response in Enterococcus faecalis caused by alkali and NaOCl. OBJECTIVE: Enterococcus faecalis (E.f) has been recognized as a main pathogen of refractory apical periodontitis, its ability to withstand environmental pressure is the key to grow in the environment of high alkaline and anti-bacterial drug that causes chronic infection in the root canal. This study aims to focus on the protein expression patterns of E.f biofilm under extreme pressure environment". METHODS: Enterococcus faecalis biofilm model was established in vitro. Liquid Chromatograph-Mass Spectrometer (LC-MS/MS)-based label free quantitative proteomics approach was applied to compare differential protein expression under different environmental pressures (pH 10 and 5% sodium hypochlorite (NaOCl)). And then qPCR and Parallel Reaction Monitoring Verification (PRM) were utilized to verify the consequence of proteomics. RESULTS: The number of taxa in this study was higher than those in previous studies, demonstrating the presence of a remarkable number of proteins in the groups of high alkaline and NaOCl. Proteins involved in ATP-binding cassette (ABC) transporter were significantly enriched in experimental samples. We identified a total of 15 highly expressed ABC transporters in the high alkaline environment pressure group, with 7 proteins greater than 1.5 times. CONCLUSIONS: This study revealed considerable changes in expression of proteins in E.f biofilm during resistance to environmental pressures. The findings enriched our understanding of association between the differential expression proteins and environmental pressures. [ABSTRACT FROM AUTHOR]

Gout is a chronic metabolic and immune disease, and its specific pathogenesis is still unclear. When the serum uric acid exceeds its saturation in the blood or tissue fluid, it is converted to monosodium urate crystals, which lead to acute arthritis of varying degrees, urinary stones, or irreversible peripheral joint damage, and in severe cases, impairment of vital organ function. Gout flare is a clinically significant state of acute inflammation in gout. The current treatment is mostly anti‐inflammatory analgesics, which have numerous side effects with limited treatment methods. Gout pathogenesis involves many aspects. Therefore, exploring gout pathogenesis from multiple perspectives is conducive to identifying more therapeutic targets and providing safer and more effective alternative treatment options for patients with gout flare. Thus, this article is of great significance for further exploring the pathogenesis of gout. The author summarizes the pathogenesis of gout from four aspects: signaling pathways, inflammatory factors, intestinal flora, and programmed cell death, focusing on exploring more new therapeutic targets. [ABSTRACT FROM AUTHOR]

Objective: The study aimed to investigate the change of amyloid precursor protein (APP) processing and amyloid β (Aβ) metabolites in linking periodontitis to Alzheimer's disease (AD). Background: Aβ is one of the main pathological features of AD, and few studies have discussed changes in its expression in peripheral tissues or analyzed the relationship between the peripheral imbalance of Aβ production and clearance. Methods: A murine model of periodontitis was established by oral infection with Porphyromonas gingivalis (P. gingivalis). Micro‐computed tomography (Micro‐CT) was used to observe the destruction of the alveolar bone. Nested quantitative polymerase chain reaction (qPCR) was used to measure small quantities of P.gingivalis DNA in different tissues. Behavioral experiments were performed to measure cognitive function in the mice. The mRNA levels of TNF‐α, IL‐6, IL‐8, RANKL, OPG, APP695, APP751, APP770, and BACE1 in the gingival tissues or cortex were detected by RT‐PCR. The levels of Aβ1‐40 and Aβ1‐42 in gingival crevicular fluid (GCF) and plasma were tested by ELISA. Results: P. gingivalis oral infection was found to cause alveolar bone resorption and impaired learning and memory. P.gingivalis DNA was detected in the gingiva, blood and cortex of the P.gingivalis group by nested qPCR (p <.05). The mRNA expression of TNF‐α, IL‐6, IL‐8, RANKL/OPG, and BACE1 in the gingival tissue was significantly higher than that in the control group (p <.05). Similarly, upregulated mRNA levels of APP695 and APP770 were observed in the gingival tissuses and cortex of the P. gingivalis group (p <.05). The levels of Aβ1‐40 and Aβ1‐42 in the GCF and plasma of the P. gingivalis group were significantly higher than those in the control group (p <.05). Conclusion: P. gingivalis can directly invade the brain via hematogenous infection. The invasion of P. gingivalis could trigger an immune response and lead to an imbalance between Aβ production and clearance in peripheral tissues, which may trigger an abnormal Aβ metabolite in the brain, resulting in the occurrence and development of AD. [ABSTRACT FROM AUTHOR]

SiOC ceramic material is a promising anode material for lithium-ion batteries. However, due to its intrinsically low electronic conductivity, it often suffers from a much lower specific capacity than the theoretical value, poor rate capability and serious potential hysteresis. In this paper, we report a core–shell structured monodisperse carbon-rich SiO1.31C1.46H0.81 submicron ceramic sphere with a free carbon content of 13.7 wt%, which is synthesized by directly annealing polysiloxane spheres derived from vinyltrimethoxysilane without adding external carbon resources. The SiO1.31C1.46H0.81 sphere has a unique microstructure, the core of which is organically assembled by large amounts of SiO1.31C1.46H0.81 primary particles of less than 20 nm and coated by a shell of 20–50 nm. As anodes for lithium-ion batteries, it presents much higher reversible capacity, initial Coulomb efficiency (ICE) and rate performance than the SiOC-based ceramic materials reported in the literature to date. At 100 mA g−1, its first reversible capacity and ICE reach ∼1107 mAh g−1 and 78.2%, respectively. At 1600 mA g−1, its stable discharge capacity is still as high as 610 mAh g−1. The excellent electrochemical performance is attributed to the moderate composition, spherical morphology and unique microstructure of the synthesized material. [ABSTRACT FROM AUTHOR]