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Chronic pancreatitis is a progressive fibroinflammatory disorder with no currently satisfactory treatment. Emerging evidence suggests an association between gut microbial dysbiosis and chronic pancreatitis. Although direct causative evidence is lacking, it is hypothesized that the gut microbiota may play a pivotal role in modulating pancreatic function via the gut–pancreas axis. Thus, modulating the gut microbiota through the administration of probiotics or prebiotics may alleviate pancreatic disorders. In this review, we first propose the potential mechanisms by which specific probiotics or prebiotics may ameliorate chronic pancreatitis, including the alleviation of small intestinal bacterial overgrowth (SIBO), the facilitation of short-chain fatty acids' (SCFAs) production, and the activation of glucagon-like peptide-1 receptors (GLP-1Rs) in the pancreas. Since there are currently no probiotics or prebiotics used for the treatment of chronic pancreatitis, we discuss research in other disease models that have used probiotics or prebiotics to modulate pancreatic endocrine and exocrine functions and prevent pancreatic fibrosis. This provides indirect evidence for their potential application in the treatment of chronic pancreatitis. We anticipate that this research will stimulate further investigation into the gut–pancreas axis and the potential therapeutic value of probiotics and prebiotics in chronic pancreatitis. [ABSTRACT FROM AUTHOR]

An analytical method was developed for the identification of primary vitamin D3 metabolites in human urine using liquid chromatography tandem mass spectrometry in positive mode. Urine samples were purified using C18 solid-phase extraction cartridges and analytical separations were performed by reversed phase liquid chromatography in gradient mode using ammonium acetate (0.01 mol L−1) and acetonitrile as the mobile phases. Identification and structural elucidation of the metabolites were carried out by comparison with mass spectral fragmentation behavior of vitamin D3 and retention characteristics. Three primary urinary vitamin D3 metabolites were identified as 25-hydroxyvitamin D3, 1α,25-dihydroxyvitamin D3 and vitamin D3 sulphate, respectively. [ABSTRACT FROM AUTHOR]

Constrained spherical deconvolution can quantify white matter fiber orientation distribution information from diffusion magnetic resonance imaging data. But this method is only applicable to single shell diffusion magnetic resonance imaging data and will provide wrong fiber orientation information in white matter tissue which contains isotropic diffusion signals. To solve these problems, this paper proposes a constrained spherical deconvolution method based on multi-model response function. Multi-shell data can improve the stability of fiber orientation, and multi-model response function can attenuate isotropic diffusion signals in white matter, providing more accurate fiber orientation information. Synthetic data and real brain data from public database were used to verify the effectiveness of this algorithm. The results demonstrate that the proposed algorithm can attenuate isotropic diffusion signals in white matter and overcome the influence of partial volume effect on fiber direction estimation, thus estimate fiber direction more accurately. The reconstructed fiber direction distribution is stable, the false peaks are less, and the recognition ability of cross fiber is stronger, which lays a foundation for the further research of fiber bundle tracking technology.

A high performance liquid chromatographic method with fluorescence detection for the determination of chloramphenicol (CAP) residues in milk was developed. Although CAP itself is non-fluorescent the aromatic nitro group of CAP could be reduced to aromatic primary amino group and fluorescamine can be used as a selective reagent for primary amines. Therefore, the CAP was derivatized with fluorescamine prior to injection in this project. The HPLC method was performed on a Diamond C18 column (250 mm x 4.6 mm i. d., 4.0 microm) with the mobile phase composed of sodium acetate buffer (0.02 mol/L, pH 6.0) -acetonitrile-tetrahydrofuran (76: 16: 8, v/v/v). The flow rate of the mobile phase was set at 1.0 mL/min, and the column was maintained at 40 degrees C. Analytes were detected by a fluorescence detector at 410 nm excitation and 508 nm emission wavelength. The standard curve was linear in the range from 0.4 microg/L to 800 microg/L. The limit of detection (LOD) was 0.2 microg/L, and the limit of quantitation (LOQ) was 0.4 microg/L. Overall recoveries were between 66.6% and 92.8% with relative standard deviations between 4.5% and 9.4%. The procedure provides a rapid, reliable and sensitive method for the determination of CAP in milk.