51 research outputs found
GEO data mining identifies potential immune-related genes in hypertrophic scar and verities in a rabbit model
Objective: Hypertrophic scar (HTS), the secondary major abnormal tissue after wound healing, is the most frequent and severe type of skin scar. Dysregulated immune response plays an important role in HTS formation. In this study, we identified the potential immune-related genes in HTS and explored their potential therapeutic significance. Methods: We first screened out the potential immune-related genes in HTS microarrays via bioinformatics analysis using public datasets. We then constructed a rabbit model of ear scar to investigate the morphological features of HTS and verify the basic expression of potential immune-related genes in HTS tissue. Finally, we used AlphaFold to determine the protein homology between human and rabbit scar tissues. Results: Bioinformatics analysis revealed 22 differentially expressed genes (DEGs) and a single differential infiltration of immune cells (naïve B cells) in HTS and normal tissues. Six of the DEGs were correlated with naïve B cell numerically. CCL2, PLXDC2 and FOXF2 were expressed in rabbit ear scar model. PLXDC2 and FOXF2 showed relatively high homology between human and rabbit scar tissues. Conclusions: PLXDC2 and FOXF2, both closely related to immune cell infiltration and specifically expressed in HTS, represent potential therapeutic targets in HTS
Rapid and visual identification of β-lactamase subtypes for precision antibiotic therapy
Abstract The abuse of antibiotics urgently requires rapid identification of drug-resistant bacteria at the point of care (POC). Here we report a visual paper sensor that allows rapid (0.25-3 h) discrimination of the subtypes of β-lactamase (the major cause of bacterial resistance) for precision antibiotic therapy. The sensor exhibits high performance in identifying antibiotic-resistant bacteria with 100 real samples from patients with diverse bacterial infections, demonstrating 100% clinical sensitivity and specificity. Further, this sensor can enhance the accuracy of antibiotic use from 48% empirically to 83%, and further from 50.6% to 97.6% after eliminating fungal infection cases. Our work provides a POC testing platform for guiding effective management of bacterial infections in both hospital and community settings
Live-Cell Pyrophosphate Imaging by in Situ Hot-Spot Generation
Controlling
the electromagnetic hot-spot generation is essential
for surface-enhanced Raman scattering (SERS) assays. Current hot-spot-based
SERS assays have been extensively studied in solutions or on substrates.
However, probing biospecies by controlling the hot-spot assembly in
living systems has not been demonstrated thus far. Herein, we report
a background-free SERS probe for imaging pyrophosphate (PPi), a biochemically
significant anion, in living cells. Intracellular PPi is able to induce
the nanoparticle dimerization, thus creating an intense electromagnetic
hot spot and dramatically enhancing the signal of the Raman reporters
residing in the hot spot. More impressively, the reporter we used
in this study provides a strong and sharp single peak in the cellular
Raman-silent region (1800–2800 cm<sup>–1</sup>), thus
eliminating the possible background interference. This strategy could
be readily extended to detect other biomarkers by only replacing the
recognition ligands
Determination of Extra- and Intra-Cellular pH Using Characteristic Absorption of Water by Near-Infrared Spectroscopy
Accurate determination of extra-cellular pH (pHe) and intra-cellular pH (pHi) is important to cancer diagnosis and treatment because tumor cells exhibit a lower pHe and a slightly higher pHi than normal cells. In this work, the characteristic absorption of water in the near-infrared (NIR) region was utilized for the determination of pHe and pHi. Dulbecco’s modified eagle medium (DMEM) and bis (2-ethylhexyl) succinate sodium sulfonate reverse micelles (RM) were employed to simulate the extra- and intra-cellular fluids, respectively. Continuous wavelet transform (CWT) was used to enhance the resolution of the spectra. Quantitative models for pHe and pHi were established using partial least squares (PLS) regression, producing relative errors of validation samples in a range of −0.74–2.07% and −1.40–0.83%, respectively. Variable selection was performed, and the correspondence between the selected wavenumbers and water structures was obtained. Therefore, water with different hydrogen bonds may serve as a good probe to sense pH within biological systems
Dual-Responsive Self-Assembled Monolayer for Specific Capture and On-Demand Release of Live Cells
We report a dual-responsive
self-assembled monolayer (SAM) on a
well-defined rough gold substrate for dynamic capture and release
of live cells. By incorporating 5′-triphosphate (ATP) aptamer
into a SAM, we can accurately isolate specific cell types and subsequently
release captured cells at either population or desired-group (or even
single-cell) levels. On one hand, the whole SAMs can be disassembled
through addition of ATP solution, leading to the entire release of
the captured cells from the supported substrate. On the other hand,
desired cells can be selectively released using near-infrared light
irradiation, with relatively high spatial and temporal precision.
The proposed dual-responsive cell capture-and-release system is biologically
friendly and is reusable with another round of modification, showing
great usefulness in cancer diagnosis and molecular analysis
Building Electromagnetic Hot Spots in Living Cells <i>via</i> Target-Triggered Nanoparticle Dimerization
Electromagnetic
hot spots of surface-enhanced Raman scattering
have been extensively employed for bioanalysis in solution or on a
substrate, but building hot spots in living systems for probing targets
of interest has not been achieved yet because of the complex and dynamic
physiological environment. Herein, we show that a target-programmed
nanoparticle dimerization can be combined with the background-free
Raman reporters (alkyne, Cî—¼C; nitrile, Cî—¼N) for multiplexed
imaging of microRNAs (miRNAs) in living cells. The <i>in</i> <i>situ</i> formation of plasmonic dimers results in an
intense hot spot, thus dramatically enhancing the Raman signals of
the reporters residing in the hot spot. More significantly, the reporters
exhibit single nonoverlapping peaks in the cellular Raman-silent region
(1800–2800 cm<sup>–1</sup>), thus eliminating spectral
unmixing and background interference. A 3D Raman mapping technique
was harnessed to monitor the spatial distribution of the dimers and
thus the multiple miRNAs in cells. This approach could be extended
to probe other biomarkers of interest for monitoring specific pathophysiological
events at the live-cell level
Colorimetric Detection of Class A Soybean Saponins by G-Quadruplex-Based Hybridization Chain Reaction
Soybean saponin is one of the important secondary metabolites in seeds, which has various beneficial physiological functions to human health. GmSg-1 gene is the key enzyme gene for synthesizing class A saponins. It is of great significance to realize the visual and rapid detection of class A saponins at the genetic level. The hybridization chain reaction (HCR) was employed to the visual detection of GmSg-1 gene, which was implemented by changing the length of the target fragment to 92 bp and using the hairpin probes we designed to detect the GmSg-1a and GmSg-1b genes. The best condition of HCR reaction is hemin (1.2 μM), Triton X-100 (0.002%), ABTS (3.8 μM), and H2O2 (1.5 mM). It was found that HCR has high specificity for GmSg-1 gene and could be applied to the visual detection of different soybean cultivars containing Aa type, Ab type, and Aa/Ab type saponins, which could provide technical reference and theoretical basis for molecular breeding of soybean and development of functional soybean products
Multiplexed Imaging of Trace Residues in a Single Latent Fingerprint
The
development of highly sensitive, selective, nondestructive,
and multiplexed imaging modalities is essential for latent fingerprint
(LFP) identification and fingerprint residues detection. Herein, we
present a versatile strategy to identify LFPs and to probe the multiple
trace residues in a single LFP simultaneously. With the purpose of
achieving high sensitivity, we for the first time introduced a polydopamine
(PDA)-triggered Au growth method to prepare superbright and multiplex
surface-enhanced Raman scattering (SERS) tags, which were endowed
with high selectivity by conjugating with specific antibodies. In
combination with a rapid Raman mapping technique, the sensitivity
of the SERS probes was down to picogram scale and all the three levels
of LFP features can be clearly seen. More significantly, the multiplexed
imaging of diverse residues in a single LFP provides more accurate
information than that using monochromatic imaging of individuals alone.
The high analytical figures of merit enable this approach great promise
for use in the fields ranging from chemical detection to molecular
imaging
Trace MicroRNA Quantification by Means of Plasmon-Enhanced Hybridization Chain Reaction
Quantifying
trace microRNAs (miRNAs) is extremely important in
a number of biomedical applications but remains a great challenge.
Here we present an enzyme-free amplification strategy called plasmon-enhanced
hybridization chain reaction (PE-HCR) for quantifying trace miRNAs
with an outstanding linear range from 1 fM to 1 pM (<i>r</i><sup>2</sup> = 0.991), along with a detection limit of 0.043 fM (1300
molecules in 50 μL of sample). The merits of the PE-HCR assay,
including high sensitivity and specificity, quantitative detection,
no enzyme involvement, low false positives, and easy-to-operate procedures,
have been demonstrated for high-confidence quantification of the contents
of miRNAs in even single cancer cells. The PE-HCR assay may open up
new avenues for highly sensitive quantification of biomarkers and
thus should hold great potentials in clinical diagnosis and prognosis
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