ORCID Profile
0000-0002-3175-1574
Current Organisations
The University of Hong Kong
,
Hong Kong Baptist University
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Publisher: JMIR Publications Inc.
Date: 09-07-2020
DOI: 10.2196/16018
Abstract: There is a growing trend in the use of mobile health (mHealth) technologies in traditional Chinese medicine (TCM) and telemedicine, especially during the coronavirus disease (COVID-19) outbreak. Tongue diagnosis is an important component of TCM, but also plays a role in Western medicine, for ex le in dermatology. However, the procedure of obtaining tongue images has not been standardized and the reliability of tongue diagnosis by smartphone tongue images has yet to be evaluated. The first objective of this study was to develop an operating classification scheme for tongue coating diagnosis. The second and main objective of this study was to determine the intra-rater and inter-rater reliability of tongue coating diagnosis using the operating classification scheme. An operating classification scheme for tongue coating was developed using a stepwise approach and a quasi-Delphi method. First, tongue images (n=2023) were analyzed by 2 groups of assessors to develop the operating classification scheme for tongue coating diagnosis. Based on clinicians’ (n=17) own interpretations as well as their use of the operating classification scheme, the results of tongue diagnosis on a representative tongue image set (n=24) were compared. After gathering consensus for the operating classification scheme, the clinicians were instructed to use the scheme to assess tongue features of their patients under direct visual inspection. At the same time, the clinicians took tongue images of the patients with smartphones and assessed tongue features observed in the smartphone image using the same classification scheme. The intra-rater agreements of these two assessments were calculated to determine which features of tongue coating were better retained by the image. Using the finalized operating classification scheme, clinicians in the study group assessed representative tongue images (n=24) that they had taken, and the intra-rater and inter-rater reliability of their assessments was evaluated. Intra-rater agreement between direct subject inspection and tongue image inspection was good to very good (Cohen κ range 0.69-1.0). Additionally, when comparing the assessment of tongue images on different days, intra-rater reliability was good to very good (κ range 0.7-1.0), except for the color of the tongue body (κ=0.22) and slippery tongue fur (κ=0.1). Inter-rater reliability was moderate for tongue coating (Gwet AC2 range 0.49-0.55), and fair for color and other features of the tongue body (Gwet AC2=0.34). Taken together, our study has shown that tongue images collected via smartphone contain some reliable features, including tongue coating, that can be used in mHealth analysis. Our findings thus support the use of smartphones in telemedicine for detecting changes in tongue coating.
Publisher: Wiley
Date: 08-03-2018
DOI: 10.1111/NEP.13000
Abstract: Angiotensin-converting enzyme inhibitors (ACEi) are widely used to deter the progression of chronic kidney disease (CKD). Besides controlling hypertension and reduction of intra-glomerular pressure, ACEi appear to have anti-fibrotic effects in the renal cortex. N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP), an endogenous tetrapeptide that is degraded by ACE, has also been shown to ameliorate the pro-fibrotic phenotype displayed in CKD in our recent study. Whether the anti-fibrotic properties of ACEi are mediated by Ac-SDKP has not been fully investigated. To delineate the role of Ac-SDKP in ACE blockade, 12-week-old male BALB/c mice underwent sham operation or unilateral ureteric obstruction (UUO). UUO mice were subjected to: (i) vehicle (ii) captopril or (iii) captopril in conjunction with S17092, a prolyl oligopeptidase inhibitor. After 7 days, mice were sacrificed and kidneys harvested for analyses. After UUO, there were heightened expressions of collagen I, collagen III, fibronectin and α-SMA associated with significant levels of tubulointerstitial injury on histological examination. Furthermore, p44/42 mitogen-activated protein kinase (MAPK) and transforming growth factor beta 1(TGF-β1) signalling were upregulated. These were significantly ameliorated by captopril treatment alone but unaffected by co-administration of captopril with S17092. Captopril treatment had resulted in elevated urinary Ac-SDKP levels, an effect that was eliminated by the co-administration with S17092. This study allowed the investigation of the renoprotective property of ACEi in the absence of Ac-SDKP and proved conclusively that Ac-SDKP is the prime anti-fibrotic mediator of captopril, acting via p44/42 MAPK and TGF-β1 signalling pathways. Future research to expand CKD armamentarium should explore the utility of augmenting Ac-SDKP levels.
Publisher: Portland Press Ltd.
Date: 02-2021
DOI: 10.1042/CS20201161
Abstract: Kallistatin is a multiple functional serine protease inhibitor that protects against vascular injury, organ damage and tumor progression. Kallistatin treatment reduces inflammation and fibrosis in the progression of chronic kidney disease (CKD), but the molecular mechanisms underlying this protective process and whether kallistatin plays an endogenous role are incompletely understood. In the present study, we observed that renal kallistatin levels were significantly lower in patients with CKD. It was also positively correlated with estimated glomerular filtration rate (eGFR) and negatively correlated with serum creatinine level. Unilateral ureteral obstruction (UUO) in animals also led to down-regulation of kallistatin protein in the kidney, and depletion of endogenous kallistatin by antibody injection resulted in aggravated renal fibrosis, which was accompanied by enhanced Wnt/β-catenin activation. Conversely, overexpression of kallistatin attenuated renal inflammation, interstitial fibroblast activation and tubular injury in UUO mice. The protective effect of kallistatin was due to the suppression of TGF-β and β-catenin signaling pathways and subsequent inhibition of epithelial-to-mesenchymal transition (EMT) in cultured tubular cells. In addition, kallistatin could inhibit TGF-β-mediated fibroblast activation via modulation of Wnt4/β-catenin signaling pathway. Therefore, endogenous kallistatin protects against renal fibrosis by modulating Wnt/β-catenin-mediated EMT and fibroblast activation. Down-regulation of kallistatin in the progression of renal fibrosis underlies its potential as a valuable clinical biomarker and therapeutic target in CKD.
Publisher: JMIR Publications Inc.
Date: 27-08-2019
Abstract: here is a growing trend in the use of mobile health (mHealth) technologies in traditional Chinese medicine (TCM) and telemedicine, especially during the coronavirus disease (COVID-19) outbreak. Tongue diagnosis is an important component of TCM, but also plays a role in Western medicine, for ex le in dermatology. However, the procedure of obtaining tongue images has not been standardized and the reliability of tongue diagnosis by smartphone tongue images has yet to be evaluated. he first objective of this study was to develop an operating classification scheme for tongue coating diagnosis. The second and main objective of this study was to determine the intra-rater and inter-rater reliability of tongue coating diagnosis using the operating classification scheme. n operating classification scheme for tongue coating was developed using a stepwise approach and a quasi-Delphi method. First, tongue images (n=2023) were analyzed by 2 groups of assessors to develop the operating classification scheme for tongue coating diagnosis. Based on clinicians’ (n=17) own interpretations as well as their use of the operating classification scheme, the results of tongue diagnosis on a representative tongue image set (n=24) were compared. After gathering consensus for the operating classification scheme, the clinicians were instructed to use the scheme to assess tongue features of their patients under direct visual inspection. At the same time, the clinicians took tongue images of the patients with smartphones and assessed tongue features observed in the smartphone image using the same classification scheme. The intra-rater agreements of these two assessments were calculated to determine which features of tongue coating were better retained by the image. Using the finalized operating classification scheme, clinicians in the study group assessed representative tongue images (n=24) that they had taken, and the intra-rater and inter-rater reliability of their assessments was evaluated. ntra-rater agreement between direct subject inspection and tongue image inspection was good to very good (Cohen κ range 0.69-1.0). Additionally, when comparing the assessment of tongue images on different days, intra-rater reliability was good to very good (κ range 0.7-1.0), except for the color of the tongue body (κ=0.22) and slippery tongue fur (κ=0.1). Inter-rater reliability was moderate for tongue coating (Gwet AC2 range 0.49-0.55), and fair for color and other features of the tongue body (Gwet AC2=0.34). aken together, our study has shown that tongue images collected via smartphone contain some reliable features, including tongue coating, that can be used in mHealth analysis. Our findings thus support the use of smartphones in telemedicine for detecting changes in tongue coating.
Publisher: Research Square Platform LLC
Date: 08-04-2022
DOI: 10.21203/RS.3.RS-1518831/V1
Abstract: Acute kidney injury (AKI) is common in hospitalized patients and is associated with high mortality. Inflammation plays a key role in the pathophysiology of AKI. Long non-coding RNAs (lncRNAs) are being increasingly recognized as regulators of the inflammatory and immune response. In this study, we first observed significantly increased urinary and circulating lncRNA Neat1 among 66 hospitalized patients with AKI versus control subjects from a primary care clinic and among kidney transplant recipients, Neat1 levels were highest after surgery followed by a prompt decline to normal levels in parallel with recovery of kidney function. Next, in a mouse model of lipopolysaccharide (LPS)-induced septic AKI, in which kidney tubular Neat1 was increased, short hairpin RNA-mediated knockdown of Neat1 in the kidney preserved kidney function by lowering BUN and serum creatinine/cystatin C, protected against tubular apoptosis and suppressed overexpression of AKI biomarkers KIM-1 and NGAL, leukocyte infiltration and both intrarenal and systemic inflammatory cytokines IL-6, TNF-α and IL-1β. Finally, in LPS-treated C1.1 mouse kidney tubular cells, Neat1 was induced via the TLR4/NF-κB signaling pathway which promoted subsequent activation of NLRP3 inflammasomes via binding with another scaffold protein, Rack1. Silencing of Neat1 in C1.1 cells ameliorated LPS-induced upregulation of IL-6, whereas overexpressing Neat1 alone without LPS stimulation was sufficient to drive C1.1 cells into a proinflammatory phenotype. In conclusion, Neat1 exerts a prominent role in AKI by promoting NLRP3 inflammasome activation and is a potential novel biomarker and therapeutic target for AKI.
Location: China
Location: United Kingdom of Great Britain and Northern Ireland
Location: Hong Kong
No related grants have been discovered for Kam Wa CHAN.