This study proposes a strategy for the rapid and simple synthesis of gold nanoparticles (CGA-AuNPs) with different particle sizes using trisodium citrate (TSC) as the first reducing agent and chlorogenic acid (CGA) as the second reducing agent. And the antibacterial activity of CGA-AuNPs with different particle sizes
in vitro
was checked by measuring the growth curves of
Escherichia coli
(
ATCC 25922
) and
Staphylococcus aureus
(
ATCC 25923
). The CGA-AuNPs obtained by the analysis of transmission electron microscope (TEM) images and ultraviolet–visible (UV–Vis) spectra were mainly spherical, and the average diameters were 18.94 ± 1.81, 30.42 ± 6.32, 37.86 ± 3.80 and 48.72 ± 6.47 nm, respectively. High-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) showed that these nanoparticles were polycrystalline gold structures. Both CGA-AuNPs and CGA have excellent antibacterial activity, and CGA-AuNPs with small particle size has a stronger antibacterial effect than the larger one. UV–Vis absorption spectrum data revealed that the synthesized CGA-AuNPs without adding other stabilizing agent were well maintained even after 26 days. This work provides a special idea to regulate the size of CGA-AuNPs with CGA by chemical synthesis, and the potent antibacterial activity of these CGA-AuNPs may be applied in the field of antibacterial in the future.
Background
Efforts to eradicate tuberculosis are largely threatened by drug-resistant tuberculosis, particularly, multidrug-resistant tuberculosis (MDR-TB). Screening and identification potential biomarkers for MDR-TB is crucial to diagnose early and reduce the incidence of MDR-TB.
Methods
To screen the differentially expressed long non-coding RNAs in MDR-TB, the lncRNA and mRNA expression profiles in serum derived from healthy controls (HCs), individuals with MDR-TB and drug-sensitive tuberculosis (DS-TB) were analyzed by microarray assay and 10 lncRNAs were randomly selected for further validation by reverse transcription-quantitative real-time PCR(RT-qPCR). The biological functions of differentially expressed mRNAs as well as relationships between genes and signaling pathways were investigated using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG), respectively.
Results
A total of 353 differentially expressed lncRNAs (312 upregulated) and 202 mRNAs (99 upregulated) were found in the MDR-TB group compared to HCs. And compared with the DS-TB group, 442 differentially expressed lncRNAs (115 upregulated) and 190 mRNAs (87 upregulated) were found in the MDR-TB group. The expression levels of lncRNA n335659 were found to differ significantly between each group by RT-qPCR. Compared with DS-TB group, the GO analysis showed that the differential mRNAs were mainly enriched in the processes associated with the detection of the chemical stimulus, the regulation of mRNA metabolic process and neutrophil activation in the MDR-TB group; the KEGG analysis indicated that the differential mRNAs between DS-TB and MDR-TB were mainly enriched in proteasome and Notch signaling pathway, which might reveal a fraction of the mechanism of MDR-TB. The discovery of the serum lncRNA n335659 might serve as a potential biomarker for MDR-TB and Notch signaling pathway provided a new clue for the investigation of the pathological mechanism of MDR-TB.
Background
To verify the differential expression of miR‐30c and miR‐142‐3p between tuberculosis patients and healthy controls and to investigate the performance of microRNA (miRNA) and subsequently models for the diagnosis of tuberculosis (TB).
Methods
We followed up 460 subjects suspected of TB, and finally enrolled 132 patients, including 60 TB patients, 24 non‐TB disease controls (TB‐DCs), and 48 healthy controls (HCs). The differential expression of miR‐30c and miR‐142‐3p in serum samples of the TB patients, TB‐DCs, and HCs were identified by reverse transcription–quantitative real‐time PCR. Diagnostic models were developed by analyzing the characteristics of miRNA and electronic health records (EHRs). These models evaluated by the area under the curves (AUC) and calibration curves were presented as nomograms.
Results
There were differential expression of miR‐30c and miR‐142‐3p between TB patients and HCs (p < 0.05). Individual miRNA has a limited diagnostic value for TB. However, diagnostic performance has been both significantly improved when we integrated miR‐142‐3p and ordinary EHRs to develop two models for the diagnosis of tuberculosis. The AUC of the model for distinguishing tuberculosis patients from healthy controls has increased from 0.75 (95% CI: 0.66–0.84) to 0.96 (95% CI: 0.92–0.99) and the model for distinguishing tuberculosis patients from non‐TB disease controls has increased from 0.67 (95% CI: 0.55–0.79) to 0.94 (95% CI: 0.89–0.99).
Conclusions
Integrating serum miR‐142‐3p and EHRs is a good strategy for improving TB diagnosis.
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