P C Leung

The Chinese University of Hong Kong, Hong Kong, Hong Kong

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Publications (375)1088.26 Total impact

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    ABSTRACT: Objectives The aims of this study were to identify the active ingredients from Portulaca oleracea L. (PO) that could provide synergism with antibiotics against methicillin-resistant Staphylococcus aureus (MRSA) and their possible mechanisms of resistance inhibition.Methods High-speed counter-current chromatography (HSCCC) coupled with gas chromatography-mass spectrometry and a panel of laboratory MRSA strains were used for checkerboard and efflux inhibitory assays.Key findingsLinoleic and oleic acids were identified from HSCCC fraction 18 of PO with synergistic antibacterial activity when combined with erythromycin against RN4220/pUL5054. Ethidium bromide efflux inhibitory studies revealed that linoleic and oleic acids may interfere the activity of MsrA pump. By comparing among a panel of linoleic and oleic acids analogues, unsaturated fatty acids in salt form with cis configuration and an increase in number of double bonds were found to further increase the antibacterial activity when used alone or in combination with antibiotics.Conclusion This study reported for the first time that two active ingredients, namely linoleic and oleic acids, were identified from PO with synergistic antibacterial activity when combined with erythromycin against MRSA RN4220/pUL5054 and possibly act by inhibiting the efflux pumps of the bacteria cells.
    Journal of Pharmacy and Pharmacology. 10/2014;
  • Pancreas 10/2014; 43(7):1126-1128. · 2.95 Impact Factor
  • Anthony C-F Ng, K -F Cheng, P -C Leung
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    ABSTRACT: Objective: BYSH, a herbal formula, was evaluated for efficacy and safety in a pilot study for patients with advanced hormone refractory prostate cancer (HRPC). Patients and Methods: The pilot study was designed as a single-center open-label trial. Patients with HRPC were treated with BYSH for 24 weeks. The primary end point was the changes in serum prostate-specific antigen (PSA) level. Safety parameters such as liver and renal functions were monitored during the study period. Results: Ten patients were eligible for the study. Most of them were stable in PSA level while taking BYSH. However, after end of the BYSH treatment, the level of PSA was increased. The median survival from diagnosis of HRPC was 16.4 months. Liver and renal functions remained normal. BYSH was well tolerated and no patient reported adverse events during the study period. Conclusion: Although it is inappropriate to make a conclusion based on the pilot study results, the trend is obvious. Further investigations should be conducted to demonstrate its clinical trial benefits. We have also briefly reviewed some relevant patents.
    Recent Patents on Inflammation & Allergy Drug Discovery 08/2014;
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    ABSTRACT: Endothelial cells were crucially involved in wound healing angiogenesis, restoring blood flow to wound tissues. Our previous study demonstrated that the Chinese 2-herb formula (NF3) possessed significant wound healing effect in diabetic foot ulcer rats with promising in vitro pro-angiogenic effects on human umbilical vein endothelial cells (HUVEC). Here we presented the comparative global proteome analysis of NF3-treated HUVEC in static or scratch conditions, screening the comprehensive molecular targets in governing the pro-angiogenic response in wound healing. Our results suggested PAI-1, specifically down-regulated in static condition and ANXA1 and ANXA2, up-regulated in scratch condition, as principal proteins which were responsible for the pro-angiogenesis in wound healing. We also identified a panel of cytoskeleton regulatory proteins in static and scratch condition, mediating the migratory behavior of NF3-treated HUVEC. The key proteins in static state included MYL9, SPAST, TPM2 and VIM while that in scratch state contained LMNA, TPM1, TPM2 and VIM. In addition, NF3 was shown to regulate transcription and translation, cell-cell interaction and ROS defense in HUVEC. Proliferation and migration assays further confirmed the identified principal proteins PAI-1 and ANXA2 which are responsible for NF3-induced pro-angiogenesis of HUVEC in wound healing. This was the first study on the global proteome expression of NF3-treated HUVEC with the identification of the differences at the molecular level, between static and scratch conditions involved in wound healing angiogenesis.This article is protected by copyright. All rights reserved
    Proteomics 07/2014; · 4.43 Impact Factor
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    ABSTRACT: Objectives Flavoxate has had a long history of use in the treatment of overactive bladder, despite the lack of documentation on its clinical efficacy and mechanism(s) of action. This study was conducted to understand how contractility characteristics of the detrusor are affected after a short period of flavoxate treatment.Methods Eight-week-old mice were treated with flavoxate for 5 days and detrusor contractile responses were examined ex vivo under different pharmacological and electrical stimuli.ResultsK+-Krebs'-induced contraction developed more slowly while 64 Hz electrical field stimulation-induced contraction developed faster in flavoxate-treated strips when compared to control. Amplitudes of maximal and steady-state contraction induced by 3 µmol/L carbachol were also larger after flavoxate treatment. Control strips showed an overall greater dependence on stimulus strength in eliciting the responses.Conclusions These findings provided new information of how short-term flavoxate treatment altered contractility characteristics at the bladder level, which may instill new interest in investigating the use of this drug in bladder disorders not responding well to conventional treatments.
    Lower urinary tract symptoms 06/2014; · 0.33 Impact Factor
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    ABSTRACT: In this cross-sectional study, we investigated volumetric bone mineral density (vBMD), bone microstructure and biomechanical competence of the distal radius in male patients with rheumatoid arthritis (RA). The study cohort comprised 50 male RA patients of average age of 61.1 years and 50 age-matched healthy males. Areal BMD (aBMD) of the hip, lumbar spine and distal radius was measured by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) of the distal radius provided measures of cortical and trabecular vBMD, microstructure and biomechanical indices.aBMD of the hip but not the lumbar spine or ultradistal radius was significantly lower in RA patients than controls after adjustment for body weight. Total, cortical and trabecular vBMD at the distal radius were, on average, -3.9% to -23.2% significantly lower in RA patients and these differences were not affected by adjustment for body weight, testosterone level or aBMD at the ultradistal radius. Trabecular microstructure indices were, on average -8.1% (trabecular number) to 28.7% (trabecular network inhomogeneity), significantly inferior while cortical pore volume and cortical porosity index were, on average, 80.3% and 63.9%, respectively significantly higher in RA patients. RA patients also had significantly lower whole-bone stiffness, modulus and failure load, with lower and more unevenly distributed cortical and trabecular stress. Density and microstructure indices significantly correlated with disease activity, severity and levels of pro-inflammatory cytokines (interleukin [IL] 12p70, Tumor Necrosis Factor, IL-6 and IL-1β). Ten RA patients had focal periosteal bone apposition most prominent at the ulnovolar aspect of the distal radius. These patients had shorter disease duration and significantly higher cortical porosity. In conclusion, HR-pQCT reveals significant alterations of bone density, microstructure and strength of the distal radius in male RA patients and provides new insight into the microstructural basis of bone fragility accompanying chronic inflammation. © 2014 American Society for Bone and Mineral Research
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 03/2014; · 6.04 Impact Factor
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    ABSTRACT: In Asia, young-onset type 2 diabetes (YOD) is characterized by obesity and increased risk for cardiovascular disease (CVD). In a genome-wide association study (GWAS) of 99 Chinese obese subjects with familial YOD diagnosed before 40-year-old and 101 controls, the T allele of rs1408888 in intron 1 of DACH1(Dachshund homolog 1) was associated with an odds ratio (OR) of 2.49(95% confidence intervals:1.57-3.96, P = 8.4×10(-5)). Amongst these subjects, we found reduced expression of DACH1 in peripheral blood mononuclear cells (PBMC) from 63 cases compared to 65 controls (P = 0.02). In a random cohort of 1468 cases and 1485 controls, amongst top 19 SNPs from GWAS, rs1408888 was associated with type 2 diabetes with a global P value of 0.0176 and confirmation in a multiethnic Asian case-control cohort (7370/7802) with an OR of 1.07(1.02-1.12, Pmeta = 0.012). In 599 Chinese non-diabetic subjects, rs1408888 was linearly associated with systolic blood pressure and insulin resistance. In a case-control cohort (n = 953/953), rs1408888 was associated with an OR of 1.54(1.07-2.22, P = 0.019) for CVD in type 2 diabetes. In an autopsy series of 173 non-diabetic cases, TT genotype of rs1408888 was associated with an OR of 3.31(1.19-9.19, P = 0.0214) and 3.27(1.25-11.07, P = 0.0184) for coronary heart disease (CHD) and coronary arteriosclerosis. Bioinformatics analysis revealed that rs1408888 lies within regulatory elements of DACH1 implicated in islet development and insulin secretion. The T allele of rs1408888 of DACH1 was associated with YOD, prediabetes and CVD in Chinese.
    PLoS ONE 01/2014; 9(1):e84770. · 3.53 Impact Factor
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    ABSTRACT: Chlorhexidine (CHX) is a widely used antimicrobial agent in dentistry. Herein, we report the synthesis of a novel mesoporous silica nanoparticle-encapsulated pure CHX (Nano-CHX), and its mechanical profile and antimicrobial properties against oral biofilms.
    PLoS ONE 01/2014; 9(8):e103234. · 3.53 Impact Factor
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    ABSTRACT: Background. Miscarriage is a very common complication during early pregnancy. So far, clinical therapies have limitation in preventing the early pregnancy loss. Chinese Medicine, regarded as gentle, effective, and safe, has become popular and common as a complementary and alternative treatment for miscarriages. However, the evidence to support its therapeutic efficacy and safety is still very limited. Objectives and Methods. To summarize the clinical application of Chinese Medicine for pregnancy and provide scientific evidence on the efficacy and safety of Chinese medicines for miscarriage, we located all the relevant pieces of literature on the clinical applications of Chinese Medicine for miscarriage and worked out this systematic review. Results. 339,792 pieces of literature were identified, but no placebo was included and only few studies were selected for systematic review and conducted for meta-analysis. A combination of Chinese medicines and Western medicines was more effective than Chinese medicines alone. No specific safety problem was reported, but potential adverse events by certain medicines were identified. Conclusions. Studies vary considerably in design, interventions, and outcome measures; therefore conclusive results remain elusive. Large scales of randomized controlled trials and more scientific evidences are still necessary to confirm the efficacy and safety of Chinese medicines during early pregnancy.
    Evidence-based Complementary and Alternative Medicine 01/2014; 2014:753856. · 1.72 Impact Factor
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    ABSTRACT: Thiol-containing antioxidant systems play an important role in regulating cellular redox homeostasis. Several anti-cancer agents act by targeting these systems by inducing the production of reactive oxygen species (ROS). Our earlier studies have shown that Eriocalyxin B (EriB), a diterpenoid isolated from Isodon eriocalyx, possesses anti-pancreatic tumour activities in vitro and in vivo. The present study further demonstrated that only thiol-containing antioxidants, N-acetylcysteine (NAC) or dithiothreitol (DTT), inhibited EriB-induced cytotoxicity and apoptosis. EriB suppressed the glutathione and thioredoxin antioxidant systems, thus increasing the intracellular ROS levels and regulating the MAPK, NFκB pathways. Treatment with EriB depleted the intracellular thiol-containing proteins in CAPAN-2 cells. In vivo studies also showed that EriB treatment (2.5 mg/kg) reduced the pancreatic tumour weights significantly in nude mice with increased superoxide levels. Taken together, our results shed important new light on the molecular mechanisms of EriB acting as an apoptogenic agent and its therapeutic potential for pancreatic cancer.
    Current Molecular Medicine 01/2014; 14(5). · 4.20 Impact Factor
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    ABSTRACT: The last decade has seen a wealth of information reporting the beneficial effects of Chinese herbal medicines. While a lot more studies were done using in vitro and in vivo research platforms, much fewer investigations were conducted according to evidence-based requirements in clinical settings. The Institute of Chinese Medicine at the Chinese University of Hong Kong (CUHK) has had the opportunity to collaborate with clinicians over the years to initiate and conduct dozens of clinical trials investigating and verifying the therapeutic values of Chinese herbs in selected disease conditions. Of the many disorders, we chose to focus on those that are known for their difficulties achieving perfect results with conventional treatment methods. Examples include non-healing ulcers, allergic conditions, degenerative diseases and cancer. Protective effects of the herbs in such chronic diseases as coronary artery disease and osteoporosis were also part of our focus. Even in healthy individuals and those recovering from chemotherapy, Chinese herbs could help with the immune system and were studied in our clinical trials as well. This paper aims to highlight the important findings from these clinical studies while at the same time, stressing the indispensable value of clinical trials in modernizing the use of Chinese herbs in present-day medicine.
    The American Journal of Chinese Medicine 01/2014; 42(3):587-604. · 2.28 Impact Factor
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    ABSTRACT: We examined the effect of a two-herb Traditional Chinese Medicine (TCM, NF3) comprising of Astragali Radix and Radix Rehmanniae, on healing of diabetic foot ulcer and its possible molecular mechanisms. This was a prospective, randomized, double-blind, placebo-controlled study. Sixteen diabetic patients were randomized to receive either placebo or NF3 for 6 months. Ulcer healing and sensory changes were examined. Molecular studies included measurement of serum tumor necrosis factor alpha (TNF-α) and RNA microarray investigation. The daily rate of reduction in ulcer area was 3.55% in the NF3 group and 1.52% in the placebo group (p=0.062). In the index limb, the number of negative tests for sensory neuropathy using monofilament was reduced from 27% to 7% in the NF3 group and from 37% to 35% in the placebo group (p<0.001). Besides, NF3 could significantly decrease the serum TNF-α level (p=0.034). Furthermore, microarray studies revealed concerted changes in gene expression following NF3 treatment implicated in fibroblast regeneration, angiogenesis and anti-inflammation. In this proof-of-concept study, 6-month treatment with NF3 was associated with improved wound healing and sensation accompanied by concerted changes in gene expression.
    Journal of Diabetes 12/2013; · 2.94 Impact Factor
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    ABSTRACT: Chinese medicine is a common name for a collection of Chinese Materia Medica with therapeutic properties for medical treatment and healing. Similar to Western pharmaceuticals, Chinese medicines are not free of risk, and have the potential to cause adverse pregnancy outcomes and affect embryonic and fetal development. However, most clinical data concerning safety of maternal exposure to Chinese medicines during pregnancy are not available and the conclusion remains elusive. Some individual clinical trials of Chinese medicines reported some minor adverse effects during pregnancy, whereas few animal studies identified some adverse maternal and perinatal effects, as well as embryotoxic potentials. Basic research and mechanistic studies of the teratogenicity of Chinese medicines are still lacking. There is an urgent need for testing the safety of Chinese medicines before recommendation and commercialization. Until more reliable and scientific research data become available, clinicians should consider both the risks and benefits before recommending Chinese medicines to pregnant women. More systematic investigations of the safety implications of the use of Chinese medicines are highly recommended, in addition to more clinical trials with a larger sample size to confirm its safety during pregnancy. This review includes a critical overview of available clinical and experimental data and provides directions to study the safety issue of Chinese medicines for pregnancy. Birth Defects Research (Part C) 99:275-291, 2013. © 2013 Wiley Periodicals, Inc.
    Birth Defects Research Part C Embryo Today Reviews 12/2013; 99(4):275-91. · 4.44 Impact Factor
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    ABSTRACT: Aims: Fallers and especially recurrent fallers are at high risk for injuries. The aim of this study was to evaluate fall epidemiology in older men with special attention to the influence of age, ethnicity and country of residence. Methods: 10,998 men aged 65 years or above recruited in Hong Kong, the United States (US) and Sweden were evaluated in a cross-sectional retrospective study design. Self-reported falls and fractures for the preceding 12 months were registered through questionnaires. Group comparisons were done by chi-square test or logistic regression. Results: The proportion of fallers among the total population was 16.5% in ages 65-69, 24.8% in ages 80-84 and 43.2% in ages above 90 (P <0.001). The corresponding proportions of recurrent fallers in the same age groups were 6.3%, 10.1% and 18.2%, respectively (P <0.001), and fallers with fractures 1.0%, 2.3% and 9.1%, respectively (P <0.001). The proportion of fallers was highest in the US, intermediate in Sweden and lowest in Hong Kong (in most age groups P <0.05). The proportion of fallers among white men in the US was higher than in white men in Sweden (all comparable age groups P <0.01) but there were no differences in the proportion of fallers in US men with different ethnicity. Conclusions: The proportion of fallers in older men is different in different countries, and data in this study corroborate with the view that society of residence influences fall prevalence more than ethnicity.
    Scandinavian Journal of Public Health 11/2013; · 1.97 Impact Factor
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    ABSTRACT: Danshen and Gegen are two commonly used Chinese herbal medicines for treatment of cardiovascular diseases. The aim of the present study was to elucidate the combination effects of these two herbs on cerebral vascular tone and their underlying mechanisms of actions. Basilar artery rings were obtained from rats and precontracted with U46619. Cumulative administrations of aqueous extracts of Danshen, Gegen, or the two herbs combined (DG; ratio 7:3) produced concentration-dependent relaxation of the artery rings. Statistical analysis on these findings produced a combination index (CI) of 1.041 at ED50, which indicates the two herbs produced additive vasodilator effects when used as a combined decoction. Removal of the endothelium had no effect on the vasodilator properties of Danshen, Gegen, and DG. However, their maximum effects (Imax) were significantly blunted by a KATP channel inhibitor glibenclamide, a non-selective K(+) channel inhibitor tetraethylammonium (TEA), and by a combination of K(+) channel inhibitors (glibenclamide+TEA+iberiotoxin+4-aminopyridine+barium chloride). In addition, Danshen, Gegen, and DG produced augmentation of KATP currents and inhibited Ca(2+) influx in vascular smooth muscle cells isolated from rat basilar arteries. Furthermore, these agents inhibited CaCl2-induced contraction in the artery rings. In conclusion, the present study showed that Danshen and Gegen produced additive vasodilator effects on rat cerebral basilar arteries. These effects were independent of endothelium-derived relaxant factors (EDRF), but required the opening of KATP channels and inhibition of Ca(2+) influx in the vascular smooth muscle cells. It is suspected that the cerebral vasodilator effects of Danshen and Gegen produced either on their own or in combination, can help patients with obstructive cerebrovascular diseases.
    Phytomedicine: international journal of phytotherapy and phytopharmacology 11/2013; · 2.97 Impact Factor
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    ABSTRACT: Mast cells are believed to contribute to the pathogenesis of osteoporosis as their number is increased in osteoporotic bones. Herba Epimedii, Fructus Ligustri Lucidi and Fructus Psoraleae are three Chinese herbs traditionally for tonifying the 'kidney system' and a herbal formula (ELP) containing the respective herbs at the weight ratio of 5 : 4 : 1 was shown to prevent osteoporosis. This study evaluated if suppression of mast cell accumulation and activity contribute to the anti-osteoporotic action of ELP. The herbs were boiled under reflux to produce the aqueous extract that was further concentrated under reduced pressure and lyophilized. An in-vivo rat osteoporosis model using hind limb unloading was employed for studying the accumulation of mast cells. The human mast cell line, LAD2, was employed to evaluate the mast cell modulating action of ELP. Mast cell number in the tibiae of hind limb unloaded rats increased significantly during the course of osteoporosis. ELP treatment (10 g/kg/day) prevented both osteoporosis and mast cell accumulation in these rats. Furthermore, ELP significantly inhibited histamine and tumour necrosis factor-α release from LAD2 cells. Mast cells contributed to hormone independent osteoporosis. The suppression of mast cell accumulation and activation may contribute to the anti-osteoporotic action of ELP.
    The Journal of pharmacy and pharmacology. 10/2013;
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    ABSTRACT: To determine whether there are race/ethnic differences in bone mineral density (BMD) by fracture history in men aged 65 years and older, we performed cross-sectional analysis in five large independent cohorts. Low BMD was associated with a higher prevalence of fracture in all cohorts, and the magnitude of the BMD differences by fracture status was similar across groups. Introduction We aimed to determine whether there are race/ethnic and geographic differences in bone mineral density by fracture history in men aged 65 years and older. Method The datasets included the Osteoporotic Fractures in Men (MrOS) Study (5,342 White, 243 African-American, 190 Asian, and 126 Hispanic), MrOS Hong Kong (1,968 Hong Kong Chinese), Tobago Bone Health Study (641 Afro-Caribbean), Namwon Study (1,834 Korean), and Dong-gu Study (2,057 Korean). The two Korean cohorts were combined. Results The prevalence of self-reported non-traumatic fracture was US white, 17.1 %; Afro-Caribbean, 5.5 %; US African-American, 15.1 %; US Hispanic, 13.7 %; US Asian, 10.5 %; Hong Kong Chinese, 5.6 %, and Korean, 5.1 %. The mean differences in hip and lumbar spine BMD between subjects with fracture and without fracture were statistically significant in all cohorts except US African American and US Asian men. There was a significant race/ethnic interaction for lumbar spine BMD by fracture status (p for interaction = 0.02), which was driven by the small number of Hispanic men. There was no interaction for femoral neck or total hip BMD. There were no significant race/ethnic differences in the odds ratio of fracture by BMD. Conclusions Low BMD was associated with a higher prevalence of fracture in all cohorts and the magnitude of the BMD differences by fracture status was similar across groups suggesting homogeneity in the BMD–fracture relationship among older men.
    Osteoporosis International 10/2013; · 4.04 Impact Factor
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    ABSTRACT: A screening survey for osteoporotic fractures in men and women in Hong Kong represents the first large-scale prospective population-based study on bone health in elderly (≥65 years) Chinese men and women. This study aims to identify the prevalence and potential risk factors of lumbar spondylolisthesis in these subjects. The lateral lumbar radiographs of 1,994 male and 1,996 female patients were analysed using the Meyerding classification. Amongst the men, 380 (19.1 %) had at least one spondylolisthesis and 43 (11.3 %) had slips at two or more levels; 283 had anterolisthesis, 85 had retrolisthesis, whereas 12 subjects had both anterolisthesis and retrolisthesis. Amongst the women, 499 (25.0 %) had at least one spondylolisthesis and 69 (13.8 %) had slips at two or more levels; 459 had anterolisthesis, 34 had retrolisthesis, whereas 6 subjects had both anterolisthesis and retrolisthesis. Advanced age, short height, higher body mass index (BMI), higher bone mineral density (BMD) and degenerative arthritis are associated with spondylolisthesis. Lower Physical Activity Scale for the Elderly (PASE) score was associated with spondylolisthesis in men; higher body weight, angina and lower grip strength were associated with spondylolisthesis in women. The male/female ratio of lumbar spondylolisthesis prevalence was 1:1.3 in elderly Chinese. Men are more likely to have retrolisthesis. • The prevalence of spondylolisthesis is 19.1 % in elderly Chinese men. • The prevalence of spondylolisthesis is 25.0 % in elderly Chinese women. • Men are more likely to have retrolisthesis. • Anterolisthesis is most commonly seen at the L4/L5 level. • Retrolisthesis is most commonly seen at the L3/L4 level.
    European Radiology 10/2013; · 4.34 Impact Factor
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    ABSTRACT: The urinary bladder expresses Ca(2+)-activated Cl(-) channels (CACC), but its physiological role in governing contractility remains to be defined. The CACC modulator niflumic acid (NFA) is widely used despite the variable results arisen from different drug concentrations used. This study was designed to examine the effects of NFA at low concentrations on detrusor strip contractility. Rat detrusor strips with mucosa-intact (+MU) and mucosa-denuded (-MU) were prepared in transverse (Tr) and longitudinal (Lg) with respect to the bladder orientation. Isometric force measurements were made at baseline (for spontaneous phasic contractile activity) and during drug stimulation (by carbachol, CCh) with and without NFA. NFA (1 and 10 μmol/L) pretreatment enhanced CCh-induced contractions more in +MU than -MU strips with no selectivity on contractile direction. For spontaneous phasic contractions, NFA-treated strips in the Tr direction showed increased phasic amplitude, while phasic frequency was unchanged. The findings suggest low concentrations of NFA having a potentiating effect on detrusor contractions that was sensitive to the MU and contractile direction.
    International Urology and Nephrology 09/2013; · 1.33 Impact Factor
  • H T Ma, J F Griffith, L Xu, P C Leung
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    ABSTRACT: This study used the "functional muscle-bone unit" concept to investigate muscle-bone interaction of the lumbar spine in subjects of varying bone mineral density. It was found that unit bone mass corresponded to a relatively more muscle mass in subjects with reduced bone mineral density, indicating a relatively higher mechanical load from muscles exerted on trabecular bone. Bone is an architecturally adaptive tissue which responds to mechanical loading. This study is proposed to use "functional muscle-bone unit" to reflect this muscle-bone interaction at spine in subjects with different bone mineral density. The study was carried out in young normal subjects (21 females; age, 29 ± 3) and elderly subjects (155 females; age, 73 ± 3.9) with varying bone mineral density. Cross-sectional area of paravertebral muscle groups was measured in MR images to indicate the muscle mass, while the bone mineral content by dual X-ray absorptiometry was used to represent the bone mass. The functional muscle-bone unit was calculated as the ratio between the bone mass to muscle mass. It showed that with aging, the muscle mass decreased with the bone mass losing. However, more pronounced reduction was found in bone mass than in muscle mass in the subjects with lower bone mineral density. Muscle-bone interaction was changed in elderly, especially in those with osteoporosis. Unit bone mass corresponded to a higher muscle mass in subjects with reduced bone mineral density than those normal subjects. This may be contributory to the occurrence of nontraumatic vertebral fractures in elderly subjects with reduced bone mineral density.
    Osteoporosis International 09/2013; · 4.04 Impact Factor

Publication Stats

5k Citations
1,088.26 Total Impact Points


  • 1984–2014
    • The Chinese University of Hong Kong
      • • Prince of Wales Hospital
      • • Institute of Chinese Medicine
      • • Department of Orthopaedics and Traumatology
      • • Faculty of Medicine
      Hong Kong, Hong Kong
  • 2013
    • Sun Yat-Sen University
      • School of Life Sciences
      Shengcheng, Guangdong, China
    • Harbin Institute of Technology Shenzhen Graduate School
      Charbin, Heilongjiang Sheng, China
  • 1986–2013
    • Prince of Wales Hospital, Hong Kong
      Chiu-lung, Kowloon City, Hong Kong
  • 1998–2012
    • The Hong Kong Polytechnic University
      • Department of Health Technology and Informatics
      Hong Kong, Hong Kong
  • 1996–2012
    • The University of Hong Kong
      • • Department of Biochemistry
      • • Department of Mechanical Engineering
      Hong Kong, Hong Kong
  • 2011
    • Shantou University
      Swatow, Guangdong, China
  • 2010
    • Chang Gung Memorial Hospital
      • Division of Endocrinology and Metabolism
      Taipei, Taipei, Taiwan
    • Zhejiang University
      Hang-hsien, Zhejiang Sheng, China
  • 2009–2010
    • Tuen Mun Hospital
      • Department of Medicine and Geriatrics
      Hong Kong, Hong Kong
  • 2006–2009
    • Sichuan University
      • Department of Otolaryngology Head-Neck Surgery
      Chengdu, Sichuan Sheng, China
    • Fudan University
      • School of Public Health
      Shanghai, Shanghai Shi, China
  • 2008
    • Racing Laboratory of the Hong Kong Jockey Club
      Hong Kong, Hong Kong
  • 1997
    • Chinese PLA General Hospital (301 Hospital)
      Peping, Beijing, China
  • 1992
    • Mayo Foundation for Medical Education and Research
      • Division of Rheumatology
      Scottsdale, AZ, United States
  • 1981–1984
    • Princess Margaret Hospital, Hong Kong
      Hong Kong, Hong Kong