Alterations and potential roles of microbial population of pregnant mouse saliva and amniotic fluid.

PROBLEM: Prenatal exposure to intrauterine inflammation (IUI) is a crucial event in PTB pathophysiology. However, the relationship between microflora and PTB is not fully elucidated. METHOD OF STUDY: In this study, we established an intrauterine inflammation mouse model via LPS intrauterine injection. The saliva and amniotic fluid were collected for 16s RNA gene sequencing. The levels of TNF-α and IL-1ß in mouse amniotic fluid were determined by ELISA assays. RESULTS: Up to 60% of the operational taxonomic units (OTUs) in the saliva and amniotic fluid of PBS-treated mice were overlapped. LPS treatment-induced changes in the abundance of oral and amniotic fluid microorganisms. Both immune-associated probiotics, salivarius and mastitidis, were still detected in saliva (at significantly increased levels) after LPS-induced intrauterine inflammation and almost no probiotics of any type were detected in amniotic fluid, suggesting that the uterine cavity seems to be more susceptible to LPS compared to the oral cavity. Moreover, the abundance of pathogenic bacteria Escherichia coli was increased in both saliva and amniotic fluid after LPS treatment. The level of TNF-α and IL-1ß in amniotic fluid is positively related to the amniotic fluid E. coli abundance. CONCLUSIONS: The microbial composition of saliva and amniotic fluid of pregnant mice was similar. LPS-induced intrauterine inflammation decreased the consistency of microbial composition in mouse saliva and amniotic fluid, increased the abundance of E. coli in saliva and amniotic fluid, and decreased the abundance of immune-associated probiotics, especially in amniotic fluid.

Measurement of BAT activity by targeted molecular magnetic resonance imaging.

OBJECTIVE: The aim of this study was to measure brown adipose tissue (BAT) activity by targeted peptide (CKGGRAKDC-NH2)-coupled, polyethylene glycol (PEG)-coated ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles with magnetic resonance imaging (MRI). METHODS: The peptide was conjugated with PEG-coated USPIO to obtain targeted probes. Male C57BL/6 J mice were randomly divided into cold exposing and control group (n = 5 per group). T2*-weighted images were obtained pre- and post-contrast probes. Histological and gene expression analyses were carried out. RESULTS: T2* relaxation time of BAT in the cold exposing group decreased more significantly compared to the control group. The calculated R2* increased with the reduction of T2* value. The ΔR2* (26.68 s-1) of BAT in the cold exposing group was significantly higher (P < 0.05) than the control group. Iron particle sediments in BAT of the cold exposing group were revealed more than the control group with Prussian blue staining. The UCP1 expression level was up-regulated after cold activation. CONCLUSIONS: BAT activity could be measured in vivo by the targeted peptide-coupled, PEG-coated USPIOs with MRI.

Novel magnetic fluorescence probe based on carbon quantum dots-doped molecularly imprinted polymer for AHLs signaling molecules sensing in fish juice and milk.

A magnetic fluorescence probe was fabricated by coating carbon quantum dots-doped molecularly imprinted polymers (MIPs) layers on the surface of Fe3O4 particles (MFMP) for detection of N-acyl homoserine lactones (AHLs) signaling molecules. N-Z-L-homoserine lactone molecular was used as the template to prepare AHLs MIP layers, employing MAA and HEMA as functional monomers. The developed MFMP owned superparamagnetism, fluorescence, fast response and class-selectivity. If AHLs (C4-HSL, C6-HSL, C8-HSL, C10-HSL, C12-HSL and C14-HSL) were captured by the MFMP, they quenched the fluorescence of the probe. Fluorescence dropped linearly in the concentration ranges of 3.65 × 10-3 µmol/L-0.96 × 10-1 µmol/L for AHLs. The MFMP was applied to the analysis of fish juice and milk samples, and recoveries ranged from 83.10% to 90.74% with relative standard deviation less than 5.1%. This study offered a novel strategy to fabricated AHLs fluorescence probe with great potential for wide-ranging application in agri-food products.

Carbon nanotube-incorporated collagen hydrogels improve cell alignment and the performance of cardiac constructs.

Carbon nanotubes (CNTs) provide an essential 2-D microenvironment for cardiomyocyte growth and function. However, it remains to be elucidated whether CNT nanostructures can promote cell-cell integrity and facilitate the formation of functional tissues in 3-D hydrogels. Here, single-walled CNTs were incorporated into collagen hydrogels to fabricate (CNT/Col) hydrogels, which improved mechanical and electrical properties. The incorporation of CNTs (up to 1 wt%) exhibited no toxicity to cardiomyocytes and enhanced cell adhesion and elongation. Through the use of immunohistochemical staining, transmission electron microscopy, and intracellular calcium-transient measurement, the incorporation of CNTs was found to improve cell alignment and assembly remarkably, which led to the formation of engineered cardiac tissues with stronger contraction potential. Importantly, cardiac tissues based on CNT/Col hydrogels were noted to have better functionality. Collectively, the incorporation of CNTs into the Col hydrogels improved cell alignment and the performance of cardiac constructs. Our study suggests that CNT/Col hydrogels offer a promising tissue scaffold for cardiac constructs, and might serve as injectable biomaterials to deliver cell or drug molecules for cardiac regeneration following myocardial infarction in the near future.