Regulation of cell proliferation by large-conductance calcium-activated potassium and volume-sensitive chloride channels in human cardiac fibroblasts

Oral presentationpublished_or_final_versionThe 15th Annual Research Conference of the Department of Medicine, The University of Hong Kong, Hong Kong, 16 January 2010. In Hong Kong Medical Journal, 2010, v. 16, suppl. 1, p. 23, abstract no. 2

Development of interfering RNA agents to inhibit SARS-associated coronavirus infection and replication.

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Potent inhibition of SARS-associated coronavirus (SCoV) infection and replication by type I interferons (IFN-α/β) but not by type II interferon (IFN-γ)

We sought to investigate the anti-severe acute respiratory syndrome (SARS)-associated coronavirus (SCoV) activities of type I (α and β) and type II (γ) interferons (IFN) in vitro. Type I IFNs protected cells from cytopathic effects (CPE) induced by SCoV, and inhibited viral genomic RNA replication in FRhk-4 cells (measured by quantitative RT-PCR) in a dose-dependent manner. Intracellular viral RNA copies were reduced 50% by IFN-α at a concentration of 25 U/ml and by IFN-β at a concentration of 14 U/ml. IFN-γ had fewer effects on inhibition of viral infection and replication. The type I IFN receptor signaling pathway in host cells is mainly involved in the inhibition of SCoV infection and replication. Type I IFNs could be used as potential agents for anti-SARS treatment.published_or_final_versio

Activation of NRG1-ERBB4 signaling potentiates mesenchymal stem cell-mediated myocardial repairs following myocardial infarction

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CHD1L protein is overexpressed in human ovarian carcinomas and is a novel predictive biomarker for patients survival

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Increased serum levels and epithelial expression of macrophage migration inhibitory factor in gastric cancer

This journal suppl. contain abstracts of the 8th Medical Research Conference, Medical Science Group, Queen Mary Hospital, Hong Kongpublished_or_final_versio

Rapid quantification of semen hepatitis B virus DNA by real-time polymerase chain reaction

Aim: To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. Methods: Hepatitis B viral DNA was isolated from HBV carriers' semen and sera using phenol extraction method and QIAamp DNA blood mini kit (Qiagen, Germany). HBV DNA was detected by conventional PCR and quantified by TaqMan technology-based real-time PCR (quantitative polymerase chain reaction (qPCR)). The detection threshold was 200 copies of HBV DNA for conventional PCR and 10 copies of HBV DNA for real time PCR per reaction. Results: Both methods of phenol extraction and QIAamp DNA blood mini kit were suitable for isolating HBV DNA from semen. The value of the detection thresholds was 500 copies of HBV DNA per mL in the semen. The viral loads were 7.5×10 7 and 1.67×10 7 copies of HBV DNA per mL in two HBV infected patients' sera, while 2.14×10 5 and 3.02×10 5 copies of HBV DNA per mL in the semen. Conclusion: Real-time PCR is a more sensitive and accurate method to detect and quantify HBV DNA in the semen. © 2005 The WJG Press and Elsevier Inc. All rights reserved.published_or_final_versio

Human pluripotent stem cell-derived mesenchymal stem cells prevent allergic airway inflammation in mice.

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MiR-637 maintains the balance between adipocytes and osteoblasts by directly targeting Osterix

Bone development is dynamically regulated by homeostasis, in which a balance between adipocytes and osteoblasts is maintained. Disruption of this differentiation balance leads to various bone-related metabolic diseases, including osteoporosis. In the present study, a primate-specific microRNA (miR-637) was found to be involved in the differentiation of human mesenchymal stem cells (hMSCs). Our preliminary data indicated that miR-637 suppressed the growth of hMSCs and induced S-phase arrest. Expression of miR-637 was increased during adipocyte differentiation (AD), whereas it was decreased during osteoblast differentiation (OS), which suggests miR-637 could act as a mediator of adipoosteogenic differentiation. Osterix (Osx), a significant transcription factor of osteoblasts, was shown to be a direct target of miR-637, which significantly enhanced AD and suppressed OS in hMSCs through direct suppression of Osx expression. Furthermore, miR-637 also significantly enhanced de novo adipogenesis in nude mice. In conclusion, our data indicated that the expression of miR-637 was indispensable for maintaining the balance of adipocytes and osteoblasts. Disruption of miR-637 expression patterns leads to irreversible damage to the balance of differentiation in bone marrow. © 2011 Zhang et al.published_or_final_versio

High-transition-temperature superconductivity in the absence of the magnetic-resonance mode

The fundamental mechanism that gives rise to high-transition-temperature (high-Tc) superconductivity in the copper oxide materials has been debated since the discovery of the phenomenon. Recent work has focussed on a sharp 'kink' in the kinetic energy spectra of the electrons as a possible signature of the force that creates the superconducting state. The kink has been related to a magnetic resonance and also to phonons. Here we report that infrared spectra of Bi2Sr2CaCu2O(8+d), (Bi-2212) show that this sharp feature can be separated from a broad background and, interestingly, weakens with doping before disappearing completely at a critical doping level of 0.23 holes per copper atom. Superconductivity is still strong in terms of the transition temperature (Tc approx 55 K), so our results rule out both the magnetic resonance peak and phonons as the principal cause of high-Tc superconductivity. The broad background, on the other hand, is a universal property of the copper oxygen plane and a good candidate for the 'glue' that binds the electrons.Comment: 4 pages, 3 figure