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Given the rising incidence of non-alcoholic fatty liver disease (NAFLD) in both adults and children, the development of a non-invasive diagnostic method for assessing disease progression to non-alcoholic steatohepatitis (NASH) has become an important research goal. Currently available non-invasive imaging technologies are only able to assess fat accumulation in the liver. Therefore, these methods are not suitable for a precise diagnosis of NASH. The standard diagnostic technique for NASH, liver biopsy, has several drawbacks, including the higher risk of complications that accompanies invasive procedures. Here, we demonstrated that in vivo mitochondrial redox metabolism was dramatically altered at an early stage, before histopathological changes, and NASH could be accurately diagnosed by in vivo dynamic nuclear polarization-magnetic resonance imaging, with carbamoyl-PROXYL as a molecular imaging probe. In addition, this technique was feasible for the diagnosis of NASH compared with histopathological findings from biopsies. Our data reveal a novel method for monitoring the dynamics of redox metabolic changes in NAFLD/NASH.

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Background: Laparoscopic sleeve gastrectomy (LSG) is a well established treatment for severe obesity and type 2 diabetes. Although the gut microbiota is linked to the efficacy of LSG, the underlying mechanisms remain elusive. The effect of LSG for morbid obesity on the gut microbiota and bile acids was assessed here. Methods: Severely obese subjects who were candidates for LSG were included and followed until 6 months after surgery. The composition and abundance of the microbiota and bile acids in faeces were assessed by 16S ribosomal RNA sequencing, quantitative PCR and liquid chromatography-mass spectrometry. Results: In total, 28 patients with a mean(s.d.) BMI of 44⋅2(6⋅6) kg/m 2 were enrolled. These patients had achieved excess weight loss of 53⋅2(19⋅0) per cent and showed improvement in metabolic diseases by 6 months after LSG, accompanied by an alteration in the faecal microbial community. The increase in-diversity and abundance of specific taxa, such as Rikenellaceae and Christensenellaceae, was strongly associated with reduced faecal bile acid levels. These changes had a significant positive association with excess weight loss and metabolic alterations. However, the total number of faecal bacteria was lower in patients before (mean(s.d.) 10⋅26(0⋅36) log 10 cells per g faeces) and after (10⋅39(0⋅29) log 10 cells per g faeces) operation than in healthy subjects (10⋅83(0⋅27) log 10 cells per g faeces). Conclusion: LSG is associated with a reduction in faecal bile acids and greater abundance of specific bacterial taxa and-diversity that may contribute to the metabolic changes.

and composites in the field of hydrothermal synthesis, as well as emulsion polymerization for nano-particles with a monodisperse size distribution [3]. Recently, microwave technology has been applied to industrial processes for material characterization to save energy and time. Although nonthermal reaction effects have been reported [4], the mechanism of monodisperse nano-particle formation under microwave irradiation remains unclear, due to the difficulty of direct observation inside reactors.The movement of particles smaller than a few micrometers is governed by Brownian motion, which causes flow around the particles. The force acting upon Brownian particles is measured using a technique called dynamic light scattering (DLS) [5], which provides the diffusion coefficient and particle size. When observation tools are installed within the reactor, the waveguide tube must be carefully designed to prevent microwave leakage. Commercial nano-particle measuring apparatuses are not necessarily suited to such designs, and it is difficult to adjust the light source power and the angle between the light axis and detector probe. Our laboratory has experience with observation of nano-particle movement [6], and measurement techniques we have developed make in situ observation of nano-particle behavior under microwave irradiation possible. This study presents an in situ observation technique for nano-particles or bubbles in a microwave reactor, and clarifies particle movement and bubble formation in water during and after microwave irradiation. Methods MaterialWe used a suspension of monodisperse polystyrene latex (PSL; 100 nm, Duke Scientific Corp.) particles as the Abstract A microwave reactor was designed for in situ observation of nano-and micro-bubbles, and size profiles during and after irradiation were measured with respect to irradiation power and time. Bubble formation in water during irradiation was observed even at temperatures below the boiling point of water. The maximum size strongly depended on radiation power and time, even at a given temperature. Nano-particles in the dispersion medium were found to play an important role in achieving more stable nucleation of bubbles around particles, and stable size distributions were obtained from clear autocorrelation by a dynamic light scattering system. Moreover, a combination of microwave induction heating and the addition of nanoparticles to the dispersion medium can prevent heterogeneous nucleation of bubbles on the cell wall. Quantitative nano-bubble size profiles obtained by in situ observation provide useful information regarding microwave-based industrial processes for nano-particle production.