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Qin H.-Y.,Hong Kong Baptist University | Wu J.C.Y.,Chinese University of Hong Kong | Tong X.-D.,Chinese Academy of Sciences | Sung J.J.Y.,Chinese University of Hong Kong | And 2 more authors.
Journal of Gastroenterology | Year: 2011

Aims: Post-infectious irritable bowel syndrome (PI-IBS) is a subset of IBS which occurs after an episode of acute gastrointestinal infections. The mechanisms of PI-IBS are not fully understood. Currently, numerous animal models have been used in the study of PI-IBS. This article reviews the strengths and weaknesses of these models. Methods: All relevant articles were identified by searching in Ovid SP from 1962, the year the term PI-IBS was coined, up to December 31, 2009. The types of model were categorized as either post-infectious or post-inflammatory, and the characteristics of each kind of model were listed. Results: Based on our literature search, 268 articles were identified. Of those articles, 50 were included in this review. The existing PI-IBS models include infection with bacteria (e.g., Campylobacter jejuni, Salmonella enterica, and Campylobacter rodentium), and infection with parasites (e.g., Trichinella spiralis, Nippostrongylus brasiliensis, and Cryptosporidium parvum). The post-inflammatory IBS models are commonly induced with chemical agents, such as acetic acid, deoxycholic acid, dextran sulfate sodium, mustard oil, zymosan, and trinitrobenzene sulfonic acid (TNBS). TNBS is the most commonly used agent for post-inflammatory IBS models, but the experimental protocol varies. These models have one or more aspects similar to IBS patients. Conclusions: Different methods have been used for the development of post-infectious or post-inflammatory IBS models. Each model has its weaknesses and strengths. More studies are needed to establish post-infection IBS models using more common pathogens. A standard protocol in developing TNBS-induced post-inflammatory IBS model is needed. © 2010 Springer.


Turley S.M.,University of Auckland | Thambyah A.,University of Auckland | Riggs C.M.,Hong Kong Jockey Club Institute of Chinese Medicine | Firth E.C.,University of Auckland | Broom N.D.,University of Auckland
Journal of Anatomy | Year: 2014

The palmar aspect of the third metacarpal (MC3) condyle of equine athletes is known to be subjected to repetitive overloading that can lead to the accumulation of joint tissue damage, degeneration, and stress fractures, some of which result in catastrophic failure. However, there is still a need to understand at a detailed microstructural level how this damage progresses in the context of the wider joint tissue complex, i.e. the articular surface, the hyaline and calcified cartilage, and the subchondral bone. MC3 bones from non-fractured joints were obtained from the right forelimbs of 16 Thoroughbred racehorses varying in age between 3 and 8 years, with documented histories of active race training. Detailed microstructural analysis of two clinically important sites, the parasagittal grooves and the mid-condylar regions, identified extensive levels of microdamage in the calcified cartilage and subchondral bone concealed beneath outwardly intact hyaline cartilage. The study shows a progression in microdamage severity, commencing with mild hard-tissue microcracking in younger animals and escalating to severe subchondral bone collapse and lesion formation in the hyaline cartilage with increasing age and thus athletic activity. The presence of a clearly distinguishable fibrous tissue layer at the articular surface immediately above sites of severe subchondral collapse suggested a limited reparative response in the hyaline cartilage. © 2014 Anatomical Society.


Liu L.-Z.,Chinese University of Hong Kong | Cheung S.C.K.,Chinese University of Hong Kong | Lan L.-L.,Chinese University of Hong Kong | Ho S.K.S.,Chinese University of Hong Kong | And 3 more authors.
Molecular and Cellular Endocrinology | Year: 2010

Berberine has been shown to have insulin-sensitizing effect, but the molecular mechanism underlying remains elusive. In this work, we investigated the effect of berberine on insulin-induced signal transduction and glucose uptake in both insulin-sensitive and insulin-resistant rat skeletal muscle cells. Berberine increased the activity of AMPK and PKCζ and AS160 phosphorylation in normal cells, but had little effect on PKB activation. In insulin-resistant state, berberine exhibited synergistic effect on insulin-induced glucose uptake and GLUT4 translocation. Berberine improved insulin-induced tyrosine-phosphorylation of IRS-1 and the recruitment of p85 to IRS-1. These changes were accompanied by enhancement in insulin-induced PKCζ and PKB activity and actin remodeling. The ameliorated insulin signal transduction was related to the inhibition of mTOR by berberine, which attenuated serine-phosphorylation of IRS-1. These results suggest that berberine may overcome insulin resistance via modulating key molecules in insulin signaling pathway, leading to increased glucose uptake in insulin-resistant cells. © 2009 Elsevier Ireland Ltd. All rights reserved.


Hoo R.L.C.,University of Hong Kong | Wong J.Y.L.,University of Hong Kong | Qiao C.F.,Hong Kong Jockey Club Institute of Chinese Medicine | Xu A.,University of Hong Kong | And 2 more authors.
Nutrition and Metabolism | Year: 2010

Background: Macrophage infiltration in adipose tissue together with the aberrant production of pro-inflammatory cytokines has been identified as the key link between obesity and its related metabolic disorders. This study aims to isolate bioactive ingredients from the traditional Chinese herb Radix Astragali (Huangqi) that alleviate obesity-induced metabolic damage through inhibiting inflammation. Methods: Active fraction (Rx) that inhibits pro-inflammatory cytokine production was identified from Radix Astragali by repeated bioactivity-guided high-throughput screening. Major constituents in Rx were identified by column chromatography followed by high-performance liquid chromatography (HPLC) and mass-spectrometry. Anti-diabetic activity of Rx was evaluated in db/db mice. Results: Treatment with Rx, which included calycosin-7-β-D-glucoside (0.9%), ononin (1.2%), calycosin (4.53%) and formononetin (1.1%), significantly reduced the secretion of pro-inflammatory cytokines (TNF-α, IL-6 and MCP-1) in human THP-1 macrophages and lipopolysaccharide (LPS)-induced activation of NF-B in mouse RAW-Blue macrophages in a dose-dependent manner. Chronic administration of Rx in db/db obese mice markedly decreased the levels of both fed and fasting glucose, reduced serum triglyceride, and also alleviated insulin resistance and glucose intolerance when compared to vehicle-treated controls. The mRNA expression levels of inflammatory cell markers CD68 and F4/80, and cytokines MCP-1, TNF-α and IL-6 were significantly reduced in epididymal adipose tissue while the alternatively activated macrophage marker arginase I was markedly increased in the Rx-treated mice. Conclusion: These findings suggest that suppression of the inflammation pathways in macrophages represents a valid strategy for high-throughput screening of lead compounds with anti-diabetic and insulin sensitizing properties, and further support the etiological role of inflammation in the pathogenesis of obesity-related metabolic disorders. © 2010 Hoo et al; licensee BioMed Central Ltd.


Pang X.,Peking Union Medical College | Song J.,Peking Union Medical College | Zhu Y.,Peking Union Medical College | Xu H.,Hong Kong Jockey Club Institute of Chinese Medicine | And 2 more authors.
Cladistics | Year: 2011

The Consortium for the Barcode of Life (CBOL) Plant Working Group (PWG) established the use of matK+rbcL as core barcodes and ITS2 as one of the supplementary loci for differentiating plants at the Third International Barcoding Conference. Here, we tested the applicability of four DNA regions (rbcL, matK, rpoC1 and ITS2) as the barcodes for identifying species within Rosaceae. Based on assessments of the success rates of PCR amplifications, the sequence quality, extent of specific genetic divergence, DNA barcoding gap and ability for species discrimination, our results suggest that ITS2 is the best of the four loci tested for barcoding Rosaceae. We further evaluated the effectiveness of ITS2 for identifying a wide range of species within Rosaceae. Of the 1410 plant samples collected from 893 species in 96 diverse genera, ITS2 successfully identified 78 and 100% of them at the species and genus levels, respectively. Therefore, our research indicated that the ITS2 region is a powerful, though not perfect, barcode for Rosaceae identification that also contributes valuable information for identifying closely related species in other plant taxonomic groups. © The Willi Hennig Society 2010.


Yu N.H.,Hong Kong Jockey Club Institute of Chinese Medicine | Ho E.N.M.,Hong Kong Jockey Club Institute of Chinese Medicine | Wan T.S.M.,Hong Kong Jockey Club Institute of Chinese Medicine | Wong A.S.Y.,Hong Kong Jockey Club Institute of Chinese Medicine
Analytical and Bioanalytical Chemistry | Year: 2010

Recombinant human erythropoietin (rhEPO), darbepoetin alfa (DPO) and methoxy polyethylene glycol-epoetin beta (PEG-EPO) are synthetic analogues of the endogenous hormone erythropoietin (EPO). These erythropoiesis-stimulating agents have the ability to stimulate the production of red blood cells and are commercially available for the treatment of anaemia in humans. These drugs are understood to have performance-enhancing effects on human athletes due to their stimulation of red blood cell production, thereby improving delivery of oxygen to the muscle tissues. Although their effect on horses has not been proven, these substances were thought to be similarly performance enhancing and have indeed been applied covertly to horses. As such, these protein-based drugs are prohibited by authorities in both human and equine sports. The method officially adopted by the International Olympic Committee (IOC) and World Anti Doping Agency (WADA) for the confirmation of rhEPO and/or DPO (rhEPO/DPO) in human urine is based on electrophoresis in combination with Western blotting. A shortcoming of the WADA method is the lack of definitive mass spectral data for the confirmation of a positive finding. Recently, a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method for the detection and confirmation of rhEPO/DPO in equine plasma was reported. However, we have not been successful in achieving the reported sensitivity. This paper presents a method for the detection and confirmation of rhEPO/DPO, as well as the newly released PEG-EPO, in equine plasma. The procedures involve immunoaffinity extraction using anti-rhEPO antibody-coated Dynabeads followed by trypsin digestion. The injected extract was further purified and concentrated using an on-line trap column in the nano-LC system. Detection and confirmation were achieved by monitoring a unique peptide segment of rhEPO/DPO/PEG-EPO using nano-liquid chromatography-tandem mass spectrometry equipped with a nanospray ionisation source operated in the selected reaction monitoring mode. rhEPO, DPO and PEG-EPO can be confirmed at 0.1, 0.2 and 1.0 ng/mL, respectively, in equine plasma. © 2010 Springer-Verlag.


Li S.-L.,Hong Kong Jockey Club Institute of Chinese Medicine | Song J.-Z.,Hong Kong Jockey Club Institute of Chinese Medicine | Qiao C.-F.,Hong Kong Jockey Club Institute of Chinese Medicine | Zhou Y.,Hong Kong Jockey Club Institute of Chinese Medicine | And 3 more authors.
Journal of Pharmaceutical and Biomedical Analysis | Year: 2010

In traditional Chinese medicine, raw and processed herbs are used to treat different diseases. Suitable chemical markers are crucial for the discrimination between raw and processed herbs. In this study, a novel strategy using UHPLC-TOFMS coupled with multivariate statistical analysis to rapidly explore potential chemical markers was proposed and validated. Using Radix Rehmanniae as a model herb, batches of raw and processed samples were determined by UHPLC-TOFMS. The datasets of tR-m/z pair, ion intensity and sample code were subjected to principal component analysis (PCA) and orthogonal partial least squared discriminant analysis (OPLS-DA) to holistically compare the difference between raw and processed samples. Once a clear cluster was found, extended statistics was performed to generate S-plot, in which the variables (tR-m/z pair) contributing most to the difference were clearly indicated as points at the two ends of "S", and the components that correlate to these ions should be the processing-induced transformed components. These transformed components could be regarded as the potential chemical markers that can be used to distinguish between raw and processed herbs. The identity of the potential markers can be identified by comparing the mass/UV spectra and retention time with that of reference compounds and/or tentatively assigned by matching empirical molecular formula with that of the known compounds published. Using this proposed strategy, leonuride or its isomer and 5-(α-d-glucopyranosyl-(1-6)-α-d-glucopyranosyloxymethyl)-2-furancarboxaldehyde were rapidly explored as the most characteristic markers of raw and processed Radix Rehmanniae, respectively. This newly proposed strategy can not only be used to explore chemical markers but also to investigate the chemical transforming mechanisms underlying traditional herb processing. © 2009 Elsevier B.V. All rights reserved.


Yao H.,Peking Union Medical College | Song J.,Peking Union Medical College | Liu C.,Peking Union Medical College | Luo K.,Peking Union Medical College | And 8 more authors.
PLoS ONE | Year: 2010

Background: The internal transcribed spacer 2 (ITS2) region of nuclear ribosomal DNA is regarded as one of the candidate DNA barcodes because it possesses a number of valuable characteristics, such as the availability of conserved regions for designing universal primers, the ease of its amplification, and sufficient variability to distinguish even closely related species. However, a general analysis of its ability to discriminate species in a comprehensive sample set is lacking. Methodology/Principal Findings: In the current study, 50,790 plant and 12,221 animal ITS2 sequences downloaded from GenBank were evaluated according to sequence length, GC content, intra- and inter-specific divergence, and efficiency of identification. The results show that the inter-specific divergence of congeneric species in plants and animals was greater than its corresponding intra-specific variations. The success rates for using the ITS2 region to identify dicotyledons, monocotyledons, gymnosperms, ferns, mosses, and animals were 76.1%, 74.2%, 67.1%, 88.1%, 77.4%, and 91.7% at the species level, respectively. The ITS2 region unveiled a different ability to identify closely related species within different families and genera. The secondary structure of the ITS2 region could provide useful information for species identification and could be considered as a molecular morphological characteristic. Conclusions/Significance: As one of the most popular phylogenetic markers for eukaryota, we propose that the ITS2 locus should be used as a universal DNA barcode for identifying plant species and as a complementary locus for CO1 to identify animal species. We have also developed a web application to facilitate ITS2-based cross-kingdom species identification (http://its2-plantidit.dnsalias.org). © 2010 Yao et al.


Cheng C.L.,Hong Kong Jockey Club Institute of Chinese Medicine | Ng K.Y.,Hong Kong Jockey Club Institute of Chinese Medicine | Xu H.X.,Hong Kong Jockey Club Institute of Chinese Medicine
Current Organic Chemistry | Year: 2010

Many Chinese herbs have been tested against herpes simplex virus (HSV) in search for new anti-herpetic agents. Extracts and novel molecules such as polysaccharides, tannins, terpenes, lignans, saponins, lectins and flavonoids have been found to be effective as anti-herpetic agents. Using different in vitro and in vivo models, novel compounds isolated from Chinese herbal medicines (CHM) have been tested and demonstrated with strong inhibitory effects on HSV through different mechanisms. CHM like Camellia sinensis, Mentha piperita, Myrica rubra, Pterocarya stenoptera, Smilax glabra and Terminalia arjuna are effective even at early stage of HSV infection to hinder viral attachment and penetration. Other CHM including Chamaecyparis obtuse, Glycyrrhiza glabra, Lobelia chinesis and Ocimumbasilicum are capable of interfering in viral replication. Nelumbo nucifera, Pithecellobium clypearia, Polygonum cuspidatum and Schefflera heptaphylla have been reported to block host cellular machineries while Plantago major and Prunella vulgaris have shown to induce immunomodulatory effect. It is also noticeable that some CHM showed dual and even multiple roles in combating HSV infection. Structural modifications of CHM derived compounds by changing the degree of sulfation and oxygenation, transforming specific moiety, addition of chemical groups and increasing molecular weight resulted in enhanced anti-herpetic activity with high selectivity and low toxicity. It is a hopeful attempt to develop topical microbicides which possess multiple actions on the early or late stage of HSV infections from CHM. In this review, we focus on the promising results and the working mechanisms on the anti-herpetic activities of several CHM and the potential of their clinical applications. © 2010 Bentham Science Publishers Ltd.


Li S.L.,Hong Kong Jockey Club Institute of Chinese Medicine | Song J.Z.,Hong Kong Jockey Club Institute of Chinese Medicine | Qiao C.F.,Hong Kong Jockey Club Institute of Chinese Medicine | Zhou Y.,Hong Kong Jockey Club Institute of Chinese Medicine | Xu H.X.,Hong Kong Jockey Club Institute of Chinese Medicine
Journal of Pharmaceutical and Biomedical Analysis | Year: 2010

In the present study, an ultra performance liquid chromatography coupled with photo-diode array detector and time-of-flight mass spectrometry (UPLC-PDA-TOFMS) based chemical profiling approach to rapidly evaluate chemical consistency between traditional and dispensing granule decoctions of traditional medicine combinatorial formulae was proposed and validated using San-Huang-Xie-Xin-Tang (SHXXT) as a model combinatorial formula. Two different kinds of decoctions, namely traditional decoction: water extract of mixed three constituent herbs of SHXXT, and dispensing granules decoction: mixed water extract of each individual herbs of SHXXT, were prepared. Batches of these two kinds of decoction samples were subjected to UPLC-PDA-TOFMS analysis, the datasets of tR-m/z pairs, ion intensities and sample codes were processed with supervised orthogonal partial least squared discriminant analysis (OPLS-DA) to holistically compare the difference between these two kinds of decoction samples. Once a clear classification trend was found in score plot, further statistics was performed to generate S-plot, in which the variables (tR-m/z pair) contributing most to the difference were clearly depicted as points at the two ends of " S" , and the components that correlate to these ions were regarded as the most changed components during decocting of combinatorial formula. The identities of the changed components can be identified by comparing the mass/UV spectra and retention times with those of reference compounds and/or tentatively assigned by matching empirical molecular formulae with those of the known compounds published in the literatures. Using the proposed approach, global chemical difference was found between traditional and dispensing granule decoctions, and berberine, palmatine, epiberberine, baicalin, wonogoside, 2-O-golloyl-1-O-cinnamoylglucose and emodin were identified as the most changed components during decocting SHXXT. It is suggested that this newly established approach could be used practically for the evaluation of chemical consistency between traditional and dispensing granule decoctions of traditional medicine combinatorial formulae. © 2010 Elsevier B.V.

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