Nanocoating of montmorillonite/Mg-β-tricalcium phosphate on orthodontic titanium miniscrews

Mini-implants (1-2 mm in diameter) are miniscrews that are placed in the jaw bones to help Orthodontists move teeth in a controlled manner. The reasons behind their increasing popularity over the past decade is that mini-implants are easily placed and removed under local anaesthetic and can withstand up to 300g force. Unfortunately, their high rate of failure (10-30%) poses a problem to clinicians and their patients alike. Advances in the field of nanotechnology presented a wide range of solutions to biological problems. We developed a nanocoating of nanoclay reinforced magnesium substituted β-TCP on titanium surface to enhance the stability of orthodontic miniscrews. ©2010 IEEE.published_or_final_versionThe 3rd IEEE International NanoElectronics Conference (INEC), Hong Kong, 3-8 January 2010. In Proceedings of 3rd INEC, 2010, p. 817-81

Experimental study of failure behavior of disturbed zone around an opening in non-persistent jointed rock masses

2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

A review of necrotising fasciitis in the extremities

Objective: To review currently available evidence on the epidemiology and methods of management for necrotising fasciitis, with particular reference to Hong Kong. Data sources and study selection: Medline, PubMed, and Cochrane Library searches of local and internationally published English language journals, from 1990 to July 2008 using the terms 'necrotising fasciitis', 'Hong Kong', 'diagnosis', 'epidemiology', 'vibrio', 'streptococci', 'clostridia', and 'management'. Data extraction: All articles involving necrotising fasciitis in Hong Kong were included in the review. Data synthesis: The incidence of necrotising fasciitis in Hong Kong and around the world has been increasing. This rapidly progressive infection is a major cause of concern, due to its high morbidity and mortality. Up to 93% of affected patients at our hospital were admitted to the Intensive Care Unit and many still died from septic complications, such as pneumonia and multi-organ failure. Radical debridements in the form of amputations and disarticulations were considered vital in 46% of the patients. Early recognition and treatment remain the most important factors influencing survival. Yet, early diagnosis of the condition is difficult due to its similarities with many other soft tissue disorders such as cellulitis. Repeated surgical debridement or incisional drainage continues to be essential for the survival of sufferers from necrotising fasciitis. Many authorities have reported that carrying out the first fasciotomy and radical debridement within 24 hours of symptom onset was associated with significantly improved survival, which also emphasises the importance of early diagnosis. Conclusion: Clinicians must adopt a high index of suspicion for necrotising fasciitis. Empirical antibiotics must be started early and repeated physical examinations should be performed, while maintaining a low threshold for tissue biopsy and surgery. The timing of the first fasciotomy and radical debridement within a window of 24 hours from symptom onset is associated with significantly improved survival.published_or_final_versio

Public knowledge of how to use an automatic external defibrillator in out-of-hospital cardiac arrest in Hong Kong

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Protocol-directed Weaning in a Neurosurgical intensive Care Unit – a Pilot Study

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Evaluating the effectiveness of personal resilience and enrichment programme (PREP) for HIV prevention among female sex workers: a randomised controlled trial.

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A Step Toward Workplace Obesity Prevention: Evaluation of Weight Management Program for Hospital-based Health Care Providers

Background: Obesity is a worldwide problem. Healthy workplace and lifestyle are crucial in preventing obesity. A workplace weight management program could create a culture of health and facilitate weight control among health care providers. The present study aims to describe and evaluate the health outcomes of the interaction of professional practice and organizational infrastructure. Method: The hospital-based weight management program was an eight-week pilot randomized controlled study for obese health care providers. The primary outcomes were body weight and body mass index. The secondary outcomes included serum fasting glucose, fasting cholesterol, triglyceride, high- and low-density lipoprotein, body fat percentage, body mass, and quality of life. The RE-AIM framework was used to examine the intervention’s reach, effectiveness, adoption, implementation and maintenance at individual and organizational levels. Results: The program successfully attained the target population. Health care providers demonstrated short-term weight loss and decreased serum fasting cholesterol level after completing the program. The excellent retention rate (95%) of the study suggested that the participants were well-engaged in self-weight management. The program was implemented with adequate resource and support from the health organization. The organization may consider continuing the program in view of its long-term benefits to health care providers. Conclusion: Supportive organizational structure and culture enhanced professional practice and improved the health outcomes of the hospital-based weight management program participants

Bioelectrical Impedance Analysis (BIA)-derived Phase Angle (PA) is a practical aid to nutritional assessment in hospital in-patients

Background: Nutritional status can be difficult to assess. Bioelectrical impedance analysis (BIA)-derived phase angle (PA), and the plasma markers citrulline and transthyretin (pre-albumin) have the potential to assist, but the protocol of fasting and resting for BIA renders the investigation impractical for routine use, especially so in populations at high risk of malnutrition.  Aims: 1- To clarify whether starving and resting are necessary for reliable measurement of PA. 2- To identify whether PA, citrulline and transthyretin correlate with nutritional status.  Methods: Eighty consenting adult in-patients were recruited. Nutritional status was determined by subjective global assessment (SGA) used as gold standard. The Malnutrition Universal Screening Tool (MUST) was used and anthropometric measurements were performed. Serum was analysed for citrulline and transthyretin. PA was measured using Bodystat 4000. The PA was considered to define malnutrition when lower than reference ranges for sex and age, and severe malnutrition if more than 2 integers below the lower limit. Anthropometric measurements were categorised according to WHO reference centiles. Ordinal logistic regression estimated the strength of association of PA, citrulline and transthyretin with SGA. PA values in the different metabolic states were compared using paired t tests.  Results: All 80 subjects completed the BIA and the nutritional assessments in the 3 different states; 14 declined to provide blood samples for the biochemical assays. Malnutrition was identified in 32 cases, severe malnutrition in 14 cases, the remaining 34 cases were deemed not to be malnourished. PA was strongly inversely associated with SGA (Odds Ratio [OR] per unit increase = 0.21, CI 0.12-0.37, p < 0.001). PA was not influenced by exercise (p=0.134) or food intake (p=0.184). Transthyretin was inversely associated with malnourished/severely malnourished states (OR = 0.98, 95% CI 0.97 – 0.99, p = 0.001), but had poorer predictive values than PA. There was no significant association between citrulline concentration and SGA (OR = 1.01, 95% CI 0.99-1.04, p = 0.348).  Conclusions: The BIA-derived PA reliably identifies malnutrition. It is strongly associated with SGA but requires less skill and experience, and out-performs circulating transthyretin, rendering it a promising and less operator-dependent tool for assessing nutritional status in hospital patients. Our novel demonstration that fasting and bed-rest are unnecessary consolidates that position

Cardiogenol C can induce Mouse Hair Bulge Progenitor Cells to Transdifferentiate into Cardiomyocyte-like Cells

<p>Abstract</p> <p>Background</p> <p>Hair bulge progenitor cells (HBPCs) are multipotent stem cells derived from the bulge region of mice vibrissal hairs. The purified HBPCs express CD34, K15 and K14 surface markers. It has been reported that HBPCs could be readily induced to transdifferentiate into adipocytes and osteocytes. However, the ability of HBPCs to transdifferentiate into cardiomyocytes has not yet been investigated.</p> <p>Methodology/Principal Findings</p> <p>The cardiomyogenic potential of HBPCs was investigated using a small cell-permeable molecule called Cardiogenol C. We established that Cardiogenol C could induce HBPCs to express transcription factors GATA4, Nkx2.5 and Tbx5, which are early specific markers for pre-cardiomyogenic cells. In prolonged cultures, the Cardiogenol C-treated HBPCs can also express muscle proteins, cardiac-specific troponin I and sarcomeric myosin heavy chain. However, we did not observe the ability of these cells to functionally contract. Hence, we called these cells cardiomyocyte-like cells rather than cardiomyocytes. We tried to remedy this deficiency by pre-treating HBPCs with Valproic acid first before exposing them to Cardiogenol C. This pretreatment inhibited, rather than improved, the effectiveness of Cardiogenol C in reprogramming the HBPCs. We used comparative proteomics to determine how Cardiogenol C worked by identifying proteins that were differentially expressed. We identified proteins that were involved in promoting cell differentiation, cardiomyocyte development and for the normal function of striated muscles. From those differentially expressed proteins, we further propose that Cardiogenol C might exert its effect by activating the Wnt signaling pathway through the suppression of Kremen1. In addition, by up-regulating the expression of chromatin remodeling proteins, SIK1 and Smarce1 would initiate cardiac differentiation.</p> <p>Conclusions/Significance</p> <p>In conclusion, our CD34⁺/K15⁺HBPCs could be induced to transdifferentiate into cardiomyocyte-like cells using a small molecule called Cardiogenol C. The process involves activation of the Wnt signaling pathway and altered expression of several key chromatin remodeling proteins. The finding is clinically significant as HBPCs offer a readily accessible and autologous source of progenitor cells for cell-based therapy of heart disease, which is one of major killers in developed countries.</p