Real-time electrocatalytic sensing of cellular respiration

In the present work we develop a real-time electrochemical mediator assay to enable the assessment of cell numbers and chemical toxicity. This allowed us to monitor metabolism down to a single cell in a low cost easy to use rapid assay which is not possible with current technology. The developed assay was based on the determination of oxygen. This was made possible via the use of electrochemical mediator ferrocene carboxylic acid (FcA). The FcA showed distinctive catalytic properties in interacting with reactive oxygen species generated from oxygen when compared to ferrocene methanol (FcMeOH). A deeper insight into the chemistry controlling this behaviour is provided. The behaviour is then taken advantage of to develop a cellular aerobic respiration assay. We describe the properties of the FcA system to detect, in real-time, the oxygen consumption of Escherichia coli DH5-α (E. coli). We demonstrated that the FcA-based oxygen assay is highly sensitive, and using a population of cells, oxygen consumption rates could be calculated down to a single cell level. More importantly, the results can be accomplished in minutes, considerably outperforming current commercially available biooxygen demand assays. The developed assay is expected to have a significant impact in diverse fields and industries, ranging from environmental toxicology through to pharmaceutical and agrochemical industries

Outcome of Laparoscopic Live Donor Nephrectomy and Impact of Double Renal Arteries: Results From Two Transplant Centres

ObjectiveLive donor kidney transplantation is consistently superior to deceased donor kidney transplantation. Laparoscopic donor nephrectomy (LDN) is increasingly accepted as a safe and preferred surgical option. To evaluate the outcome of LDN and the impact of multiple arteries, a retrospective review was conducted on patients in two transplant centres.MethodsFifty patients including eight with double vessels were studied. Standard left transperitoneal LDN was performed. Grafts including those with double vessels were prepared using the bench technique. Postoperative outcomes (up to 1 year) for donors and recipients were studied. The outcomes of recipients of a single or double vessel graft were compared.ResultsAll donors had an eventful recovery. No difference was found between the single and multiple vessels groups for operating time (168.21 ± 5.712 minutes vs. 197.50 ± 15.755 minutes) or hospital stay (3.21±0.165 days vs. 4.13±0.789 days). The recipient outcomes including hospital stay (10.17±0.596 days vs. 12.13 ± 1.797 days) and creatinine levels at day 7 (106.53 ± 5.583 μmol/L vs. 107.13 ± 11.857 μmol/L) and 1 year (120.21 ± 6.562 μmol/L vs. 124.75 ± 11.857 μmol/L) were similar. No ureteric stricture or graft loss was noted at 1-year follow-up. Recipient complications included lymphocoele (n = 2), haematoma (n = 3 with 2 requiring exploration), sepsis (n = 1), renal artery stenosis (n = 2 with 1 stented), repeated anastomosis (n = 1), and incisional hernia (n = 1). No differences were noted between the two groups.ConclusionOur results showed that overall donor morbidity rate was low, as reflected by the short hospital stay. Also, the overall parameters of the recipients were good. In particular, no ureteric stricture was noted, and graft survival was 100% at 1 year. The outcomes of the reconstructed group, despite the technical challenge, were similar to those of the single-vessel group

What are the opportunities for manufacturing in the “one belt one road” initiative? The case of Hong Kong’s textiles and clothing sector

The One Belt, One Road (hereafter OBOR) initiative is a development strategy launched by China in 2015. Its aim is to increase economic co-operation among countries along the China’s Silk Road Economic Belt and 21st Century Maritime Silk Road that connect Asia, Europe and Africa. As one of China’s important economic drivers, Hong Kong’s anticipated gains taking part in this initiative are substantial. This is particularly true for companies in the textiles and clothing (T&C) sectors, as the OBOR initiative offers investment opportunities in developing low-cost production bases in developing countries and promotes global trade. The main objective of this paper is twofold. First, it investigates how Hong Kong can strengthen its “superconnector” role, facilitating sustainable trade and development in the T&C industries among some OBOR countries. Specific measures are identified so that T&C companies in Hong Kong can establish and facilitate technological upgrades and transformation to potential production facilities in some developing countries under the OBOR initiative. This would contribute to the sustainable development of the T&C sectors in Hong Kong. Second, the study extends the gravity trade model to analyze the development of T&C trade patterns between Hong Kong and OBOR countries. Especially it covered some of the key factors not considered in previous studies, such as Logistics Performance Index (LPI), demographical factors, and those related to the business environment and policies. The analysis covers the impacts of country-specific, social, economic and supply chain factors on T&C trade. Based on the results, recommendations are provided to address how Hong Kong helps to facilitate trade and development of the T&C sectors under the OBOR initiative

Prolonged exposure to bacterial toxins downregulated expression of toll-like receptors in mesenchymal stromal cell-derived osteoprogenitors

<p>Abstract</p> <p>Background</p> <p>Human mesenchymal stromal cells (MSCs, also known as mesenchymal stem cells) are multipotent cells with potential therapeutic value. Owing to their osteogenic capability, MSCs may be clinically applied for facilitating osseointegration in dental implants or orthopedic repair of bony defect. However, whether wound infection or oral microflora may interfere with the growth and osteogenic differentiation of human MSCs remains unknown. This study investigated whether proliferation and osteogenic differentiation of MSCs would be affected by potent gram-positive and gram-negative derived bacterial toxins commonly found in human settings.</p> <p>Results</p> <p>We selected lipopolysaccharide (LPS) from <it>Escherichia coli </it>and lipoteichoic acid (LTA) from <it>Streptococcus pyogenes </it>as our toxins of choice. Our findings showed both LPS and LTA did not affect MSC proliferation, but prolonged LPS challenge upregulated the osteogenic differentiation of MSCs, as assessed by alkaline phosphatase activity and calcium deposition. Because toll-like receptors (TLRs), in particularly TLR4 and TLR2, are important for the cellular responsiveness to LPS and LTA respectively, we evaluated their expression profiles serially from MSCs to osteoblasts by quantitative PCR. We found that during osteogenic differentiation, MSC-derived osteoprogenitors gradually expressed TLR2 and TLR4 by Day 12. But under prolonged incubation with LPS, MSC-derived osteoprogenitors had reduced TLR2 and TLR4 gene expression. This peculiar response to LPS suggests a possible adaptive mechanism when MSCs are subjected to continuous exposure with bacteria.</p> <p>Conclusion</p> <p>In conclusion, our findings support the potential of using human MSCs as a biological graft, even under a bacterial toxin-rich environment.</p

Impacts of electronic device use on adolescents' sexual knowledge, attitude and perception during the COVID-19 pandemic: A representative sexuality survey

BackgroundCOVID-19 pandemic has led to school closure and social distancing measures for infection control. Many young people thus spent more time on electronic devices and the Internet. This study aimed to determine if and how sexual knowledge, perception and behavior as well as sexuality among Hong Kong adolescents were affected as a result.MethodsYouth Sexuality Study conducted by The Family Planning Association of Hong Kong (FPAHK) evaluated the sexual knowledge, attitudes and behaviors and sexual health of youth every 5 years since 1981 with adaptations made to the changing environment. We analyzed this cross-sectional data on sexual knowledge, attitude, and experiences as well as the impacts of COVID-19 on daily life, health and relationships. Univariate analysis was conducted to investigate the relationships between the time spent on electronic devices and sexuality, while mediation analyses using the PROCESS procedure were performed to further explore differences in time spent on electronic devices.ResultsDuring the COVID-19 pandemic, the majority of our participants spent more time on social media and browsing the Internet on electronic devices with less time for extracurricular activities and learning. Nonetheless, there was better overall sexual knowledge and a lower degree of sexual stigma with a higher overall acceptance of sexual minorities. The mediation analyses found that sexual content [Conditional effect = 0.024 (95% CI 0.008, 0.043)] and engagement online [Conditional effect = 0.036 (CI 0.021, 0.053)] could indirectly influence the effect of screen time on the frequency of sexual practices.ConclusionPolicymakers and frontline professionals should re-examine the pedagogy of the present sex education and consider online sex education as the key mode of delivery while guiding the proper use of electronic devices in the learning and exploration of sexual knowledge

Performance of screening tests for oesophageal squamous cell carcinoma: a systematic review and meta-analysis

Background and Aims: This systematic review and meta-analysis aims to compare the pooled diagnostic accuracy of the currently available esophageal squamous cell carcinoma (ESCC) screening tests. Methods: A comprehensive literature search of Embase and Medline (up to October 31, 2020) was performed to identify eligible studies. We pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) for ESCC screening tools using a bivariate random-effects model. The summary receiver operating characteristic (sROC) curves with area under the curve (AUC) were plotted for each screening test. Results: We included 161 studies conducted in 81 research articles involving 32,209 subjects. The pooled sensitivity, specificity, and AUC (95% CIs) of the major screening tools were: (1). Endoscopy (per-oral endoscopy): 0.94 (0.87-0.97), 0.92 (0.87-0.95), and 0.97 (0.96-0.99); (2) Endoscopy (transnasal endoscopy): 0.85 (0.70-0.93), 0.96 (0.91-0.98), and 0.97 (0.95, -0.98); (3). MicroRNA: 0.77 (0.75-0.80), 0.78 (0.75-0.80), and 0.85 (0.81-0.87); (4). Autoantibody: 0.45 (0.36-0.53), 0.91 (0.89-0.93), and 0.84 (0.81-0.87); and (5). Cytology: 0.82 (0.60-0.93), 0.97 (0.88-0.99), and 0.97 (0.95-0.98). There was high heterogeneity. Conclusions: The diagnostic accuracy seems comparable between Cytology and endoscopy, whilst autoantibody and microRNAs bear potential as future non-invasive screening tools for ESCC. To reduce ESCC-related death in the high-risk populations, it is important to develop a more accurate and less invasive screening test