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1.  The quest for modernisation of traditional Chinese medicine 
Traditional Chinese medicine (TCM) is an integral part of mainstream medicine in China. Due to its worldwide use, potential impact on healthcare and opportunities for new drug development, TCM is also of great international interest. Recently, a new era for modernisation of TCM was launched with the successful completion of the Good Practice in Traditional Chinese Medicine Research in the Post-genomic Era (GP-TCM) project, the European Union’s Seventh Framework Programme (FP7) coordination action on TCM research. This 3.5-year project that involved inputs from over 200 scientists resulted in the production of 20 editorials and in-depth reviews on different aspects of TCM that were published in a special issue of Journal of Ethnopharmacology (2012; volume 140, issue 3). In this narrative review, we aim to summarise the findings of the FP7 GP-TCM project and highlight the relevance of TCM to modern medicine within a historical and international context. Advances in TCM research since the 1950s can be characterised into three phases: Phase I (1950s-1970s) was fundamental for developing TCM higher education, research and hospital networks in China; Phase II (1980s-2000s) was critical for developing legal, economic and scientific foundations and international networks for TCM; and Phase III (2011 onwards) is concentrating on consolidating the scientific basis and clinical practice of TCM through interdisciplinary, interregional and intersectoral collaborations. Taking into account the quality and safety requirements newly imposed by a globalised market, we especially highlight the scientific evidence behind TCM, update the most important milestones and pitfalls, and propose integrity, integration and innovation as key principles for further modernisation of TCM. These principles will serve as foundations for further research and development of TCM, and for its future integration into tomorrow’s medicine.
PMCID: PMC3689083  PMID: 23763836
Evidence-based medicine; Chinese herbal medicine; Acupuncture; History; Science; Efficacy; Safety; Integrity; Integration; Innovation
2.  Retinoic Acid Receptor-Dependent, Cell-Autonomous, Endogenous Retinoic Acid Signaling and Its Target Genes in Mouse Collecting Duct Cells 
PLoS ONE  2012;7(9):e45725.
Vitamin A is necessary for kidney development and has also been linked to regulation of solute and water homeostasis and to protection against kidney stone disease, infection, inflammation, and scarring. Most functions of vitamin A are mediated by its main active form, all-trans retinoic acid (tRA), which binds retinoic acid receptors (RARs) to modulate gene expression. We and others have recently reported that renal tRA/RAR activity is confined to the ureteric bud (UB) and collecting duct (CD) cell lineage, suggesting that endogenous tRA/RARs primarily act through regulating gene expression in these cells in embryonic and adult kidney, respectively.
Methodology/Principal Findings
To explore target genes of endogenous tRA/RARs, we employed the mIMCD-3 mouse inner medullary CD cell line, which is a model of CD principal cells and exhibits constitutive tRA/RAR activity as CD principal cells do in vivo. Combining antagonism of RARs, inhibition of tRA synthesis, exposure to exogenous tRA, and gene expression profiling techniques, we have identified 125 genes as candidate targets and validated 20 genes that were highly regulated (Dhrs3, Sprr1a, and Ppbp were the top three). Endogenous tRA/RARs were more important in maintaining, rather than suppressing, constitutive gene expression. Although many identified genes were expressed in UBs and/or CDs, their exact functions in this cell lineage are still poorly defined. Nevertheless, gene ontology analysis suggests that these genes are involved in kidney development, renal functioning, and regulation of tRA signaling.
A rigorous approach to defining target genes for endogenous tRA/RARs has been established. At the pan-genomic level, genes regulated by endogenous tRA/RARs in a CD cell line have been catalogued for the first time. Such a catalogue will guide further studies on molecular mediators of endogenous tRA/RARs during kidney development and in relation to renal defects associated with vitamin A deficiency.
PMCID: PMC3458940  PMID: 23049847
3.  Total protein, albumin and low-molecular-weight protein excretion in HIV-positive patients 
BMC Nephrology  2012;13:85.
Chronic kidney disease is common in HIV positive patients and renal tubular dysfunction has been reported in those receiving combination antiretroviral therapy (cART). Tenofovir (TFV) in particular has been linked to severe renal tubular disease as well as proximal tubular dysfunction. Markedly elevated urinary concentrations of retinal-binding protein (RBP) have been reported in patients with severe renal tubular disease, and low-molecular-weight proteins (LMWP) such as RBP may be useful in clinical practice to assess renal tubular function in patients receiving TFV. We analysed 3 LMWP as well as protein and albumin in the urine of a sample of HIV positive patients.
In a cross-sectional fashion, total protein, albumin, RBP, cystatin C, and neutrophil gelatinase-associated lipocalin (NGAL) were quantified in random urine samples of 317 HIV positive outpatients and expressed as the ratio-to-creatinine (RBPCR, CCR and NGALCR). Exposure to cART was categorised as none, cART without TFV, and cART containing TFV and a non-nucleoside reverse-transcriptase-inhibitor (TFV/NNRTI) or TFV and a protease-inhibitor (TFV/PI).
Proteinuria was present in 10.4 % and microalbuminuria in 16.7 % of patients. Albumin accounted for approximately 10 % of total urinary protein. RBPCR was within the reference range in 95 % of patients while NGALCR was elevated in 67 % of patients. No overall differences in urine protein, albumin, and LMWP levels were observed among patients stratified by cART exposure, although a greater proportion of patients exposed to TFV/PI had RBPCR >38.8 μg/mmol (343 μg/g) (p = 0.003). In multivariate analyses, black ethnicity (OR 0.43, 95 % CI 0.24, 0.77) and eGFR <75 mL/min/1.73 m2 (OR 3.54, 95 % CI 1.61, 7.80) were independently associated with upper quartile (UQ) RBPCR. RBPCR correlated well to CCR (r2 = 0.71), but not to NGALCR, PCR or ACR.
In HIV positive patients, proteinuria was predominantly of tubular origin and microalbuminuria was common. RBPCR in patients without overt renal tubular disease was generally within the reference range, including those receiving TFV. RBP therefore appears a promising biomarker for monitoring renal tubular function in patients receiving TFV and for distinguishing patients with normal tubular function or mild tubular dysfunction from those with severe renal tubular disease or Fanconi syndrome.
PMCID: PMC3444380  PMID: 22883485
Proteinuria; Albuminuria; Retinol-binding protein; RBP; Cystatin C; Neutrophil gelatinase-associated lipocalin; NGAL; Tenofovir; HIV
4.  Kidneys of Alb/TGF-β1 Transgenic Mice Are Deficient in Retinoic Acid and Exogenous Retinoic Acid Shows Dose-Dependent Toxicity 
Nephron. Experimental Nephrology  2010;114(4):e127-e132.
Alb/TGF-β1 transgenic mice overexpress active transforming growth factor-β1 (TGF-β1) in the liver, leading to increased circulating levels of the cytokine and progressive renal fibrosis. This study was designed to explore if exogenous all-trans retinoic acid (tRA) prevents renal fibrosis in this animal model.
The retinoid profile in kidney and liver of wild-type and Alb/TGF-β1 transgenic mice was examined by high-performance liquid chromatography and slow-release pellets containing different amounts of tRA were implanted subcutaneously to treat the Alb/TGF-β1 transgenic mice, starting at 1 week of age; mice were sacrificed 2 weeks later.
Kidneys of 3-week-old wild-type mice had abundant tRA, which was completely absent in kidneys of the transgenic mice. Low doses of tRA (6–10.7 mg/kg/day) failed to affect renal fibrosis although it tended to suppress the mRNA expression of some molecular markers of fibrosis and retinal dehydrogenase 2 (RALDH2), a gene encoding a key tRA-synthesising enzyme. These tendencies disappeared, mortality tended to increase and RALDH2 and connective tissue growth factor (CTGF) mRNAs significantly increased in the medium-dose group (12.7–18.8 mg/kg/day). High doses (20.1–27.4 mg/kg/day) showed even higher toxicity with increased renal fibrosis and significant mortality.
Alb/TGF-β1 transgenic mice are characterised by depletion of endogenous renal tRA. Exogenous tRA dose-dependently increases mortality and kidney fibrosis, which is associated with dose-dependent regulation of renal RALDH2 and CTGF mRNA expression.
PMCID: PMC2865400  PMID: 20110732
All-trans retinoic acid; Transforming growth factor-β1; Connective tissue growth factor; Retinal dehydrogenase 2; Fibrosis
5.  Endogenous Retinoic Acid Activity in Principal Cells and Intercalated Cells of Mouse Collecting Duct System 
PLoS ONE  2011;6(2):e16770.
Retinoic acid is the bioactive derivative of vitamin A, which plays an indispensible role in kidney development by activating retinoic acid receptors. Although the location, concentration and roles of endogenous retinoic acid in post-natal kidneys are poorly defined, there is accumulating evidence linking post-natal vitamin A deficiency to impaired renal concentrating and acidifying capacity associated with increased susceptibility to urolithiasis, renal inflammation and scarring. The aim of this study is to examine the presence and the detailed localization of endogenous retinoic acid activity in neonatal, young and adult mouse kidneys, to establish a fundamental ground for further research into potential target genes, as well as physiological and pathophysiological roles of endogenous retinoic acid in the post-natal kidneys.
Methodology/Principal Findings
RARE-hsp68-lacZ transgenic mice were employed as a reporter for endogenous retinoic acid activity that was determined by X-gal assay and immunostaining of the reporter gene product, β-galactosidase. Double immunostaining was performed for β-galactosidase and markers of kidney tubules to localize retinoic acid activity. Distinct pattern of retinoic acid activity was observed in kidneys, which is higher in neonatal and 1- to 3-week-old mice than that in 5- and 8-week-old mice. The activity was present specifically in the principal cells and the intercalated cells of the collecting duct system in all age groups, but was absent from the glomeruli, proximal tubules, thin limbs of Henle's loop and distal tubules.
Endogenous retinoic acid activity exists in principal cells and intercalated cells of the mouse collecting duct system after birth and persists into adulthood. This observation provides novel insights into potential roles for endogenous retinoic acid beyond nephrogenesis and warrants further studies to investigate target genes and functions of endogenous retinoic acid in the kidney after birth, particularly in the collecting duct system.
PMCID: PMC3033902  PMID: 21326615
6.  Silencing genes in the kidney: antisense or RNA interference? 
Nephrology Dialysis Transplantation  2008;23(7):2115-2118.
PMCID: PMC2441770  PMID: 18326563
antisense; gene therapy; siRNA

Results 1-6 (6)