46 research outputs found
The use of three-dimensional printing technology in orthopaedic surgery: A review
Three-dimensional (3-D) printing or additive manufacturing, an advanced technology that 3-D physical models are created, has been wildly applied in medical industries, including cardiothoracic surgery, cranio-maxillo-facial surgery and orthopaedic surgery. The physical models made by 3-D printing technology give surgeons a realistic impression of complex structures, allowing surgical planning and simulation before operations. In orthopaedic surgery, this technique is mainly applied in surgical planning especially revision and reconstructive surgeries, making patient-specific instruments or implants, and bone tissue engineering. This article reviews this technology and its application in orthopaedic surgery.published_or_final_versio
MicroRNA let-7 suppresses nasopharyngeal carcinoma cells proliferation through downregulating c-Myc expression
Aims: This study aimed at evaluating the potential anti-proliferative effects of the microRNA let-7 family in nasopharyngeal carcinoma (NPC) cells. In addition, the association between let-7 suppression and DNA hypermethylation is examined. Materials and methods: Levels of mature let-7 family members (-a,-b,-d,-e,-g, and-i) in normal nasopharyngeal cells (NP69 and NP460) and nasopharyngeal carcinoma cells (HK1 and HONE1) were measured by real-time quantitative PCR. Cell-proliferation assay and c-Myc immunohistochemical staining were performed on NPC cells transfected with let-7 precursor molecules. In addition, expression changes in let-7 family members in response to demethylating agents (5-azacytidine and zebularine) were also examined. Results: In comparison with the normal nasopharyngeal cells, let-7 (-a,-b,-d,-e,-g, and-i) levels were reduced in nasopharyngeal carcinoma cells. Ectopic expression of the let-7 family in nasopharyngeal carcinoma cells resulted in inhibition of cell proliferation through downregulation of c-Myc expression. Demethylation treatment of nasopharyngeal carcinoma cells caused activation of let-7 expression in poorly differentiated nasopharyngeal carcinoma cells only. Conclusion: Our results suggested that miRNA let-7 might play a role in the proliferation of NPC. DNA methylation is a potential regulatory pathway, which is affected when let-7 is suppressed in NPC cells. However, the extent of DNA hypermethylation/hypomethylation in regulating let-7 expression requires further elucidation. © The Author(s) 2010. This article is published with open access at Springerlink.com.published_or_final_versionSpringer Open Choice, 21 Feb 201
Anti-SARS-CoV-2 antibody responses are attenuated in patients with IBD treated with infliximab.
OBJECTIVE: Antitumour necrosis factor (anti-TNF) drugs impair protective immunity following pneumococcal, influenza and viral hepatitis vaccination and increase the risk of serious respiratory infections. We sought to determine whether infliximab-treated patients with IBD have attenuated serological responses to SARS-CoV-2 infections. DESIGN: Antibody responses in participants treated with infliximab were compared with a reference cohort treated with vedolizumab, a gut-selective anti-integrin α4β7 monoclonal antibody that is not associated with impaired vaccine responses or increased susceptibility to systemic infections. 6935 patients were recruited from 92 UK hospitals between 22 September and 23 December 2020. RESULTS: Rates of symptomatic and proven SARS-CoV-2 infection were similar between groups. Seroprevalence was lower in infliximab-treated than vedolizumab-treated patients (3.4% (161/4685) vs 6.0% (134/2250), p<0.0001). Multivariable logistic regression analyses confirmed that infliximab (vs vedolizumab; OR 0.66 (95% CI 0.51 to 0.87), p=0.0027) and immunomodulator use (OR 0.70 (95% CI 0.53 to 0.92), p=0.012) were independently associated with lower seropositivity. In patients with confirmed SARS-CoV-2 infection, seroconversion was observed in fewer infliximab-treated than vedolizumab-treated patients (48% (39/81) vs 83% (30/36), p=0.00044) and the magnitude of anti-SARS-CoV-2 reactivity was lower (median 0.8 cut-off index (0.2-5.6) vs 37.0 (15.2-76.1), p<0.0001). CONCLUSIONS: Infliximab is associated with attenuated serological responses to SARS-CoV-2 that were further blunted by immunomodulators used as concomitant therapy. Impaired serological responses to SARS-CoV-2 infection might have important implications for global public health policy and individual anti-TNF-treated patients. Serological testing and virus surveillance should be considered to detect suboptimal vaccine responses, persistent infection and viral evolution to inform public health policy. TRIAL REGISTRATION NUMBER: ISRCTN45176516
Consensus guidelines for the use and interpretation of angiogenesis assays
The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference
Sigma Energy App
Sigma energy app is a mobile application for subscribers to various energy subscriptions. The subscribers can use this mobile application to access information regarding their consumption, invoices and active subscriptions. The mobile application that was built consists of a GUI and a web API as middleman between the application and the database. Sigma energy app är en mobilapplikation för abonnenter av diverse energiabonnemang. Med denna mobilapplikation kan abonnenterna direkt hämta information om sin förbrukning, fakturor och aktiva abonnemang. Mobiltelefonapplikationen som har konstruerats består av ett GUI samt av ett web-API som mellanhand mellan applikationen och databasen
Scheduling strategies for Interactive Video-On-Demand service
This reseach project is a theoretical and experimental investigation of scheduling strategies that can improve the performance of Interactive Video-On-Demand (IVOD) servers. Examples of IVOD can be found in digital libraries, hypermedia, distance learning, entertainment and telemarketing applications. In contrast to the delivery of movies, interactive video programmes are seldom linear. IVOD programmes usually consist of short video branches separated by user interactions. IVOD users will not be satisfied with long latency for start-up and restart of video branches. Further, interactive media may be accompanied by other forms of data such as voice, audio, image, text or graphics. For that reason, an IVOD server also needs to provide adequate residual bandwidth to support sporadic data requests arising from user interactions. Therefore, an IVOD scheduler needs to address performance issues such as startup latencies, queuing time, admission probabilities, and data throughput. As the length of video branches in IVOD are typically short, departures and startup of requests are frequent. The adverse effects of these frequent transients on throughput and robustness must also be treated explicitly. The user-driven interactivity in IVOD service poses scheduling problems that have not been fully addressed by the admission control and static disk-scheduling techniques previously proposed for VOD servers. In this research, we identify IVOD performance issues and present solutions to address some of these performance issues. Our philosophy is to dynamically schedule request admissions and disk accesses in an IVOD server, by exploiting the use of run-time information. At the disk scheduling level, we introduce two disk scheduling strategies. To minimize start-up latency and achieve good tolerance against variable-bit-rate, we introduce the GS_EDF scheduler. To reduce the long start-up latency inherent to seek-reducing disk schedulers, we introduce the GSCS scheduler which can significantly reduce start-up latency while preserving a high stream throughput. At the admission level, we introduce admission prioritizing strategies which can improve queuing time and total throughput of a busy IVOD server without causing undesirable throughput degradation and bandwidth fragmentation. To improve sporadic service throughput without losing streaming throughput, we introduce an optimum readsize control technique to maximize the disk efficiency dynamically. The readsize control technique is also novel in removing disk rotational latencies. All the techniques introduced in this thesis are verified by comprehensive performance evaluations. The results confirm that these proposed strategies can improve IVOD service in various dimensions of performance
Strategic Management: An Evaluation of the Use of Three Learning Methods in China
The authors examine the use of three learning methods in the teaching of a strategic management course for a postgraduate programme jointly run by the Hong Kong Polytechnic University and the Zhejiang University. The three methods used in this study include an in-company consultancy project; a new business venture simulation; and the case method. The results of a survey of postgraduate students' perceptions reveal that overall the new business venture simulation provides a more successful learning experience than the case method as well as in-company consultancy project
The Use of Computer-Assisted, Interactive Role-Play Simulation in China
This paper reports feedback from postgraduate students’ participation in Fish Bank, Ltd., a computer-assisted, interactive role-playing simulation in which teams are to manage a fishing company to compete in the fishing industry. The survey focused on how students in China viewed computer-assisted, interactive role-playing simulation as a learning tool for them and how they perceived that this type of role-playing simulation can actually help them understand the subject matter more in depth. Overall results are highly favorable