The gut microbiome and intestinal failure-associated liver disease.

Intestinal failure-associated liver disease (IFALD) is a common hepatobiliary complication resulting from long-term parenteral nutrition (PN) in patients with intestinal failure. The spectrum of IFALD ranges from cholestasis, steatosis, portal fibrosis, to cirrhosis. Development of IFALD is a multifactorial process, in which gut dysbiosis plays a critical role in its initiation and progression in conjunction with increased intestinal permeability, activation of hepatic immune responses, and administration of lipid emulsion. Gut microbiota manipulation including pre/probiotics, fecal microbiota transplantation, and antibiotics has been studied in IFALD with varying success. In this review, we summarize current knowledge on the taxonomic and functional changes of gut microbiota in preclinical and clinical studies of IFALD. We also review the function of microbial metabolites and associated signalings in the context of IFALD. By providing microbiota-targeted interventions aiming to optimize PN-induced liver injury, our review provides perspectives for future basic and translational investigations in the field.

Emerging role of regulated cell death in intestinal failure-associated liver disease.

Intestinal failure-associated liver disease (IFALD) is a common complication of long-term parenteral nutrition that is associated with significant morbidity and mortality. It is mainly characterized by cholestasis in children and steatohepatitis in adults. Unfortunately, there is no effective approach to prevent or reverse the disease. Regulated cell death (RCD) represents a fundamental biological paradigm that determines the outcome of a variety of liver diseases. Nowadays cell death is reclassified into several types, based on the mechanisms and morphological phenotypes. Emerging evidence has linked different modes of RCD, such as apoptosis, necroptosis, ferroptosis, and pyroptosis to the pathogenesis of liver diseases. Recent studies have shown that different modes of RCD are present in animal models and patients with IFALD. Understanding the pathogenic roles of cell death may help uncover the underlying mechanisms and develop novel therapeutic strategies in IFALD. In this review, we discuss the current knowledge on how RCD may link to the pathogenesis of IFALD. We highlight examples of cell death-targeted interventions aiming to attenuate the disease, and provide perspectives for future basic and translational research in the field.

miRNA-425-5p enhances lung cancer growth via the PTEN/PI3K/AKT signaling axis.

BACKGROUND: miRNAs regulate a multitude of cellular processes and their aberrant regulation is linked to human cancer. However, the role of miR-425-5p in lung cancer (LCa) is still largely unclear. Here, we explored the role of miR-425-5p during LCa tumorigenesis. METHODS: Cell proliferation was evaluated by cell counting Kit-8 and colony formation assay. Western blot and real-time PCR were accordingly used to detect the relevant proteins, miRNA and gene expression. Luciferase reporter assays were used to illustrate the interaction between miR-425-5p and PTEN. RESULTS: We demonstrate that miR-425-5p is overexpressed in LCa tissue and enhances the proliferative and colony formation capacity of the LCa cell lines A549 and NCI-H1299. Through predictive binding assays, PTEN was identified as a direct gene target and its exogenous expression inhibited the pro-cancer effects of miR-425-5p. Through its ability to down-regulate PTEN, miR-425-5p activated the PI3K/AKT axis. CONCLUSION: We conclude that miR-425-5p promotes LCa tumorigenesis through PTEN/PI3K/AKT signaling.

[Remote sensing of seasonal variation in column concentration of atmospheric CO2 and CH4 in Hefei].

In order to observe two kinds of greenhouse gases, CO2 and CH4, making the biggest contribution to global warming, a ground-based Fourier transform near-infrared spectral remote sensing system was developed to record the perpendicular incidence sun spectra from February 2012 to April 2013 in Hefei continuously. The measured total transmittances in the atmosphere were obtained from perpendicular incidence sun spectra. Methods of line-by-line and low-order polynomial approximation were used to model the total atmospheric transmittances in forward model. The measured transmittance spectra were fitted iteratively using the modeled transmittance spectra in the regions of CO2 6,150-6,270 and CH4 5,970-6,170 cm(-1) in order to obtain their column concentrations. The column-average dry-air mole fractions of CO2 and CH4 were obtained with the internal standard function of O2 column concentrations. CO2 and CH4 daily average values of column-average dry-air mole fractions changed with a larger fluctuation and obvious seasonal periodicity. Their monthly average values were consistent as a whole, although there were different characteristics. Compared with the results reported by Japanese greenhouse-gas satellite in the area of Waliguan, there was a time lag corresponding to peak and trough of CO2 content and the change from peak to trough costed a longtime. CHR content showed variation tendency of unique peak and trough, higher in summer and lower in winter, compared with average values of nationwide CH4 column concentrations based on SCIAMACHY data. The variation characteristics were related to complex factors such as the balance of source and sink, meteorological and climate conditions, and required long-term observation and further study.

[Optical properties research of Bacillus subtilis spores by Fourier transform infrared spectroscopy].

The authors measured IR transmission spectra of two different concentrations of Bacillus subtilis spores by using Fourier transform infrared spectroscopy (FTIR) technology. The mass extinction cross section k of Bacillus subtilis spores was calculated according to Lambert-Beer law and the imaginary part n(i) of the complex refractive index was also calculated through k. The real part n(r) of the complex refractive index was derived from the KK (Kramers-Kronig) relationship and the experimental results were also analyzed and discussed with the study of measurement and analysis method of the complex refractive index on Bacillus subtilis spores, it is of great significance to further research the absorption and scattering characteristics, and to broaden the measurement and remote sensing technology method of the biological aerosols.

[Concentration inversion of high temperature air from FTIR spectra and analyzing residual error structure].

The spectral line widths of theory and experiment are analyzed with different temperatures; the line strengths under room temperature in HITRAN database are corrected to measured temperature, and then synthetic spectra are calculated. With the nonlinear least squares fit between measured spectra and calibration spectra, standard gas concentrations of CO at different temperatures are obtained. The inversion concentration error of this algorithm at room temperature is less than 5% with high precision. But with the temperature increasing, the concentration error will increase gradually. At the same time, there is the same apparent structure to component CO in the residual spectrum. Also, with higher temperature, the structure is more obvious and can not be removed by increasing the number of fitting. Comparing experimental results and theoretical analysis, the temperature correction methods of calibration spectra, which are not suitable for high temperature gas, are the main reason for inversion error at higher temperature. These results have important significance for further research on accurately correcting parameters and how to inverse the high temperature gas concentrations more accurately.

[Ozone concentration inversion based on multi-reflected cell FTIR spectra and correlation analysis].

The stratosphere ozone plays the protective action role for human and the ground-level ozone is harmful to human health. Monitoring ozone with different ways and methods took an active part in understanding distribution and transformation of ozone, which was useful to controlling pollution emission. Spectra were got by multi-reflected white cell Fourier transform infrared (FTIR) spectrometer, inversed with nonlinear least squares (NLLSQ) method and then the concentrations of ozone were got exactly. The correlations of measured ozone concentration time series by Fourier transform infrared spectrometer, open path UV differential optical absorption spectrometer and ozone analyzer of the Thermo Corporation were significant. The results showed that the measured ozone absolute concentrations with different monitoring methods and instruments had some differences, but the concentration diurnal variations were coincident and the correlations were good. Therefore, ozone concentration inversion method, based on multi-reflected cell Fourier transform infrared spectrum and not reported in domestic articles, could be used as an effective technique to measure ozone concentration.

[Monitoring and analysis of urban ozone using open path Fourier transform infrared spectrometry].

An ozone monitoring system was developed by the method of open path Fourier transform infrared (OP-FTIR) spectrometry based on our FTIR spectrometer. In order to improve measurement precision and detection limit, the quantitative analysis was completed to get ozone concentration by combining synthetic background spectrum method which uses information from HITRAN database and instrumental line shape, and nonlinear least squares (NLLSQ) method. The measurement methods for system detection limit were discussed and the result is 1.42 nmol x mol(-1) with sixteen times averages. The authors developed continuous monitoring experiments in the suburban area of Hefei. For the day and month measurement results, the authors analyzed their variations with the generation sources. The result has shown that this system is reliable and precise and can be used as a new device and method for national ozone monitoring.

Serum bile acid level and fatty acid composition in Chinese children with non-alcoholic fatty liver disease.

OBJECTIVE: To determine serum bile acid (BA) and fatty acid (FA) profiles in Chinese children with non-alcoholic fatty liver disease (NAFLD). METHODS: A total 76 children aged 4-17 years were categorized into three groups according to the presence and absence of as well as the severity of NAFLD, that is, non-NAFLD (control), mild and moderate to severe NAFLD groups, respectively, based on their liver ultrasonography findings. Serum BA and FA profiles were quantified separately by mass spectrometry and gas chromatography. General linear models were performed to assess the differences among the groups. RESULTS: After adjusted for potential confounders, children with NAFLD had higher levels of chenodeoxycholic acid (CDCA), unconjugated primary BAs (CDCA + cholic acid) but lower levels of deoxycholic acid (DCA), taurodeoxycholic acid (TDCA), glycodeoxycholic acid (GDCA), total DCA (DCA + TDCA + GDCA), glycolithocholic acid (GLCA) and total lithocholic acid (GLCA + taurolithocholic acid) than children without NAFLD. As for FAs, children with mild and moderate to severe NAFLD had higher levels of n-7 monounsaturated FA. CONCLUSIONS: Circulating BA and FA profiles may change in children with NAFLD. Further studies are needed to determine their associations and to understand the underlying mechanism of action.

[Quantitative analysis of nitrate in atmospheric particulates PM2.5 with Fourier transform infrared spectroscopy].

Airborne fine particulate matter PM2.5 as one of composite core pollutants of air pollution is concerned and NO as one of the main components of water-soluble ions has an important impact on precipitation and human health, so searching a method of rapid and reliable detection is an important work. According to advantages of the Fourier transform infrared spectroscopy technology, the infrared spectrum of NO3- in NH4NO3 was compared with PM2.5 by a sampling method of making film. The result shows that their spectra are consistent with each other. A range of infrared spectra of different masses of NO3- were measured and the absorbance was fitted with mass, correlation and mass range of which are 0.994 8 and 7.82-73.78 microg, respectively. According to the corresponding relationship of mass between solution and sample film, the FTIR of the sample film was measured directly and mass concentrations of NO3- in a month (between 2012-03-20 and 2012-04-20) of Hefei area are listed and the average is 4.1713 microg x m(-3).