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Australia — ASIC Sues Citrofresh.

Australia — IDT's Blackman, Mattick Awarded "Science Oscars".

Australia — Medical Fellowship in Honor of Zhou.

Australia — Stem Cell Sciences Joins European Program.

China — Johnson & Johnson Breaks Ground for the Biggest Base in Asia.

China — Beijing Sinovac Biotech Seeks Volunteers for 2nd Bird Flu Vaccine Trial.

China — CAS Establishes Five More Research Institutes.

China — China to Increase Support for Drug Research and Production.

China — Chinese Government Reduces Drug Price.

Hong Kong — Shaw Prize for Six Scientists.

India — India Ayurvedic Medicine Gives Hope to Alzheimer.

India — Indian Drug Maker Buys DHA.

Japan — Takeda's Actos Reduces Risk of Second Stroke.

Malaysia — KL's New Initiatives for its Biotech Industry.

Singapore — Professor Philip Ingham to Boost Singapore's Biomedical Drive.

Singapore — Health Agreements Between Singapore and Chinese Companies.

Singapore — Biosensors Confident of Approval for its Stent.

Singapore — More Drug Companies Conducting Trials in Singapore.

Singapore — New Breed of Doctors to be Trained at Duke-NUS Medical School.

Taiwan — Taiwan Hosts International Biologics and Vaccine Conference.

Taiwan — Taiwan and Vietnam Sign Agreement to Fight Disease.

Taiwan — Taiwan to Invest NT$300 million for Biofuel Research Efforts.

Taiwan — Taiwan's Medical Sensor Breakthrough.

Taiwan — HIV Vaccine Trials in Taiwan.

Others — Vietnam Prepares for Potential Bird Flu Outbreaks Among Humans.

Others — AIDS Meeting Urged to Rethink Prevention Strategy.

Others — WHO Warns About Drug-Resistant TB.

AUSTRALIA – HIV trial validates novel drug mechanism.

SINGAPORE – IBN engineered artificial human livers for drug testing and discovery.

SINGAPORE – Scientists at A*STAR's Genome Institute of Singapore catch evolving germs and cancer cells early.

SINGAPORE – DocDoc and Chatter Buzz Media enter strategic partnership to launch Asia's first healthcare Content Marketing Network.

UNITED STATES – New method developed to expand blood stem cells for bone marrow transplant.

UNITED STATES – Fibrocell/UCLA study on human skin cells yields promising results.

UNITED STATES – Metal stents are effective treatment for blocked bile ducts.

UNITED STATES – Pain drug may prevent preemie lung damage.

UNITED STATES – Gene x3 helps corn grow in acidic soil.

UNITED STATES – Cancer Genetics selected by Gilead Sciences, Inc. to provide clinical trial services for chronic lymphocytic leukemia.

UNITED KINGDOM – DaTSCAN™ SPECT imaging demonstrates impact on the diagnosis of patients with clinically uncertain dementia.

AFRICA – Failing vaccine strategies need to be revamped.

AFRICA – RegeneCure's membrane implant shows 40% accelerated healing time of severe bone fractures.

APTAR PHARMA Provides Unit-Dose Nasal Spray Technology for Treatment of Opioid Overdose

Cloudera, Broad Institute Collaborate on the Next Generation of the Genome Analysis Toolkit

Singapore-based Luye Medical Group Completes Acquisition of Healthe Care, Australia's Third Largest Private Healthcare Group

FEI Launches Apreo – Industry-Leading Versatile, High-Performance SEM

BOGE Publishes New Guide on Specifying Compressed Air for Healthcare

Takara Bio USA, Inc. and Integrated DNA Technologies Announce Collaboration to Support Targeted RNA Sequencing

Pelican BioThermal Announces Launch of New Asia Headquarters in Singapore

A Faster Way to Separate Proteins with Electrophoresis

Biosensors Announces Strategic Agreement with Cardinal Health

BGI and Clearbridge BioMedics Partner to Develop China CTC Liquid Biopsy Market towards Precision Medicine

China’s 2018 Future Science Prize winners announced.

China tops world in alcohol-related deaths.

Nanotech to inhibit wheat sprouting.

New antibacterial hydrogel for wound healing.

Genetically modified Zika virus vaccine to treat brain tumour.

Semi-elastic nanoparticles to deliver drugs.

Chinese stent for heart disease reported safe in European patients.

First China-developed drug for colorectal cancer approved in China.

More medicines added to the national list of essential medicines.

Recent revisions in Chinese regulations open new doors for contract research organisations.

The following topics are under this section:

• Making an Appointment with MyDoc
• Improving Access to Mental Health Treatment with Technology
• Enhancing the knowledge and technical skills of healthcare practitioners within the interventional cardiology community (AICT-AsiaPCR)

Permanent metallic stents are frequently used in cardiovascular interventions, due to the many advantages metals possess in bulk and surface properties, design and chemistry, as well as their high modulus and ease of producing thin sections. However, the presence of foreign bodies in humans is associated with many long-term safety concerns; removal of the stent is therefore preferred through a second intervention after recovery. Based primarily on this consideration, biodegradable stents have been of significant interest in the past few years. This paper reports the manufacturing and near-physiological testing of a novel Biodegradable Metallic Coronary Stent (BMCS). To date, very limited literature is available on this aspect of research. Generally, magnesium is reactive and generally difficult to process. However, preliminary results demonstrate strong feasibility of fabricating low-profiled magnesium-based biodegradable coronary stents. Near-physiological tests based on a specially designed accelerated radial stent fatigue system were carried out. Results show that the biodegradable stents retained their arterial scaffolding functions for up to one year (simulated) before totally being resorbed into the biological fluid past its point of functionality. The results obtained so far show great promise for application.

Stents have been used successfully for treating stenosis in the vertebral artery ostium. The size of stent is found to be an important link in stent design, implantation strategy, and clinical outcome. However, there is no direct evidence of a relationship between stent expansion ratio and the stented artery. This study investigated the influence of stent expansion ratio on local hemodynamics (such as pressure distribution and pressure gradient) of vertebral artery ostial stenosis to determine a possible biomechanical mechanism. Computer-aided design of models with stents with different expansion ratios (i.e., 1.00, 1.125, and 1.25) and internal flow fields were created. All the models were meshed and simulated using computational fluid dynamics (CFD) tools. The comparisons of pressure distribution and pressure gradient are specifically presented. The results showed that the pressures increase and the pressure gradient decreases after stent implantation. The mean pressure at the stented region rises significantly with the increase of stent oversize. The heterogeneity of the pressure gradient was reduced at the stented region in the case with the expansion ratio of 1.125, whereas this effect was not obvious in other expansion ratio cases. Additionally, the combination of higher pressure and a lower pressure gradient in the case with the expansion ratio of 1.125 was significantly observed. This study demonstrated that the proper size of stent, especially with regards to the expansion ratio, is an important factor influencing the treatment of vertebral artery ostial stenosis. It is the recognition of the necessity to consider the relationship between expansion ratio and stenosis in vertebral artery ostium. These findings could help to address the optimization of hemodynamic performance for stent implantation.

In-stent restenosis (ISR) after stent implantation, especially in tapered vessels, remains an obstacle in the long-term benefits of stenting. In the present study, a finite element method (FEM) was employed to investigate the expansion process of balloon-expandable stents in tapered vessels (the TV model) and their interactions. For comparison, a numerical model of the same stent deployment in a straight vessel was also investigated. Results showed that in the TV model, the peak tissue stresses took place at the distal end of the tapered vessel. The node displacements of the stent's proximal and distal ends remained consistent before the stent contacted the tapered vessel, while the proximal end was larger than the distal end after the stent contacted the tapered vessel. The regions of maximum stresses in the stent after expansion were concentrated in the corners of the diamond cells of the stent's proximal end. The investigation provided some interpretations of the clinical observations in tapered vessels and also provided stent design proposals for tapered vessels. The FEM quantified the mechanical properties of stents in tapered vessels, and can help clinicians select appropriate stents, assist designers in pretests and create new stents made especially for tapered vessels.

Different stent structures lead to different deformations of blood vessels, such as different cross-sectional shapes, which further influence the blood flow patterns. In this paper, six non-commercial stents with different link structures called I-, C-, S-, U-, N- and W-types were considered. Their influences on arteries with five different curvatures (i.e., 0${}^{\circ }$, 15${}^{\circ }$, 30${}^{\circ }$, 45${}^{\circ }$ and 60${}^{\circ }$) were studied using finite element method. Four indices including the maximum plastic strain of stents, the rate of expansion, the maximum von Mises stress and the ellipticity of arteries, were compared for all cases. The results showed that the S-type or U-type stents, with larger plastic strain and lower von Mises stress on the arteries, provided the optimal outcome. As the link structures became complex, the arterial expansion increased monotonically, while the ellipticity of arteries showed a decreasing tendency in the vessel models. The present study could be useful for the commercial design and clinic selection of a stent with different link structures for different curved arteries.

Coronary artery disease (CAD) is the number one killer for both men and women in the United States. To date, unavailability of human coronary arteries due to ethical and biosafety issues has not allowed for many experimental studies on understanding the pathophysiology of CAD. Also, patient-specific arterial blockage conditions are very difficult to estimate using 2D imaging, which prevents the development of effective surgical mitigation steps. Additionally, to date, a majority of stent surgery failures (over 50%), mainly attributed to poor stent design (such as an oversized stent causing local damage of arterial wall and subsequent growth of scar tissue through the stent leading to re-blocking the artery, or in-stent restenosis), are impossible to evaluate. In the current work, a methodology to fabricate patient-specific three-layer biofidelic coronary artery surrogates was developed. This novel method involves the generation of a true-scale MRI-based patient-specific 3D arterial lumen model, which is 3D printed. A four-part silicone material system is developed, which precisely mimics the nonlinear biomechanical behavior of arterial layers, namely the intima (innermost), media (middle) and adventitia (outer). Using the 3D printed arterial lumen model as a positive mold, thin layers ($0.3\pm 0.05$mm) of the layer-specific silicone-based materials are deposited, and subsequently pulled out once cured. The final product is a three-layer coronary artery model which is exactly of the same size and dimensions, and similar mechanical property as that of the actual coronary artery of a patient. Such surrogate models would be extremely helpful for cardiologists and heart surgeons to understand patient-specific atherosclerotic conditions (based on the location and size of blockages), simulate CAD-based surgeries and also evaluate stent implantation procedures. Additionally, these coronary artery surrogate models will allow stent manufacturers to design better and more reliable stents in the future to avoid stent oversizing-based arterial damage conditions and improve stent deployment techniques.

The torsional performance is a major mechanical property of stent. A stent with good torsional performance is easy to deform along blood vessels without damaging the vascular wall to avoid in-stent restenosis (ISR). Therefore, this study aimed to study the effect of stent parameters on torsional performance. The effect of stent parameters on torsional performance was studied via finite element method (FEM). The twist metric (TM) and stress distribution of various stents were compared. The TM values of stents with I-, S-, M-, C-, and V-shaped linkers were 0.0190, 0.0191, 0.0184, 0.0141, and 0.0201$\mathrm{\text{N}}\cdot \mathrm{\text{rad}}$, respectively. In addition, the TM value of the stent increased by 35.85 times when the number of linkers was increased from 2 to 8 and the stent was twisted at the same angular displacement in clockwise direction. The TM value of the stent with 1.13^∘ tapering was 0.010 $\mathrm{\text{N}}\cdot \mathrm{\text{rad}}$, which was lower by 47.64% compared with that of cylindrical stent. Compared with the shape of the linker, the number of linkers had a more remarkable effect on torsional performance. Torsional performance was observably enhanced with the decrease in the number of linkers. Among the five stents with different linker shapes, the torsional performance of the stent with C-shaped linker was the best. Besides, the torsional performance of the tapered stent was better than that of the cylindrical stent. Moreover, the torsional performance increased by increasing the stent tapering. This work might provide insights into better stent design and clinical decisions.

In-stent restenosis (ISR), which is a common complication after stent intervention, affects the long-term outcome of stent intervention. Suitable implantation planning will effectively reduce the incidence of ISR. The aim of this study is to investigate the effect of different implantation planning on the mechanical behavior of stents in tapered vessels with multiple stenoses and select a better implantation planning. The finite element method (FEM) was used in this study. A different planning was designed as follows: (a) using a cylindrical balloon to deploy cylindrical stent (plan CC), (b) using the tapered balloon to deploy cylindrical stent (plan TC) and (c) using the tapered balloon to deploy tapered stent (plan TT). When the stent was expanded to the maximum diameter, the position of maximum vascular stress all appeared at distal plaque in three implantation plans. After balloon was deflated, the vascular stress in plan TC was the minimum. Using tapered balloon to deploy cylindrical stent has advantages in the tapered vessels with multiple stenoses and could reduce the probability of ISR. Moreover, this method could assess the mechanical properties of stent deployment in multiple stenoses and then select a better implantation planning.

Computational fluid dynamics analyses were performed on three models which have a giant aneurysm with or without a stenosis. The first is a model with an aneurysm (no stenosis and no stent), the second is a model with a preaneurysm stenosis, and the third is a model with an aneurysm implanted with a stent. The increase in pressure in aneurismal sac caused by a 50% stenosis is about 10.3mmHg at peak systole (comparison between the second model and the first model). It must pay attention to the increase of the pressure for the patient which has an aneurysm accompanied by a stenosis when making the treatment plan. Otherwise, it may cause the aneurysm rupture.

Information about technological innovation and its evolutionary path can be explored by patent analysis. Therefore, for those firms which are dependant on large investments and a high business performance, such as stent manufacturers, integrating patent information with business strategy is the critical issue. The competition between stent manufactures is intensifying because of increasing global volume demand and improving technological performance. From a resource-based view, adopting a co-opetition strategy is essential for firms to keep sustainable competitive advantage. Over the last decade, patent rights have become a major tool of the co-opetition strategy. This study analyzes patent data from the USPTO during 1984 to 2005 and constructs patent information indicators to verify the process of technology evolution. On these grounds, we can understand the relative technological position and technological strength of the major manufacturers in this industry and also inspect their changes of position and business scope to examine the relationship between each firm's technology strategy and business strategy.

Computational models provide a powerful tool for pre-clinical assessment of medical devices and early evaluation of potential risks to the patient in terms of plaque fragmentation and in-stent restenosis (ISR). Using a suitable constitutive model for arterial tissue is key for the development of a reliable computational model. Although some inelastic phenomena such as stress softening and permanent deformation likely occur due to the supra-physiological loading of arterial tissue during the stenting procedure, hyperelastic constitutive models have been employed in most of the previously developed computational models. This study presents a finite element model for stent deployment into a patient-specific stenosed artery while inelastic arterial behaviors due to supra-physiological loading of the tissue have been considered. Specifically, the maximum stress in the plaque and the arterial layers which is the main cause of plaque fracture during stent deployment and the surgically-induced injury (damage) in the arterial wall, as the main cause of ISR, are presented. The results are compared with the commonly-used hyperelastic behavior for arterial layers. Furthermore, the effects of arterial material parameter variation, analogues to different patients, are investigated. A higher amount of damage is predicted for the artery which shows a higher stress in a specific strain.

Coronary artery disease treatments like coronary artery bypass grafting and percutaneous transluminal coronary angioplasty have several drawbacks, such as their invasive nature. Two main types of stents, bare metal stents (BMSs) and drug-eluting stents (DESs), are implemented to overcome these difficulties. The BMS offers strong mechanical support but can cause in-stent thrombosis and restenosis. Conventional DES, comprising a metal platform coated with drug-conjugated polymers, initially lowers restenosis but can cause early thrombosis and late in-stent restenosis. To overcome these limitations, biodegradable DESs are being explored to provide short-term support without long-term complications. However, biodegradable metal-based DES can trigger immunogenic reactions when degraded. The next generation of stents is shifting toward bioresorbable polymer-based DES because their degradation products are compatible with the metabolic system of the body. This review discusses the in vivo degradation mechanisms of bioresorbable polymers such as polyglycolic acid, polylactic acid, and polycaprolactone (PCL) acid polymers. It was observed that these polymers primarily degrade via ester bond hydrolysis, influenced by polymer properties such as molecular weight, morphology, glass transition temperature, and composition. Additionally, this overview highlights ongoing advancements in bioresorbable polymer-based scaffolds like DESolve${}^{\text{®}}$NX and FANTOM${}^{\text{®}}$. These bioresorbable scaffolds are fabricated from poly-L-lactide acid and desamino tyrosine-based polymers, respectively. Polylactic-co-glycolic acid-coated platinum–chromium stents have also demonstrated effective performance, being fully absorbed within 4–6 months postimplantation. Moreover, PCL acid-based drug-eluting bifurcation stents have shown promise in treating cardiovascular diseases. However, the review emphasizes the necessity for continued research to address the existing challenges and enhance patient outcomes.

Poor compatibility between blood and metallic coronary artery stents is one reason for arterial restenosis. Immobilization of heparin on stent's surface is feasible for improving compatibility. We examined possible surface-coupling agents for anticoagulant agent immobilization. Hexamethylene diisocyanate (HMDI) was examined as surface-coupling agent to activate 316L stainless steel (e.g. stent material). Afterwards, we grafted PEG on the HMDI activated surface to provide heparin with higher conformational freedom and a more hydrophilic environment. The effectiveness of HMDI activated and PEG grafted surface was confirmed by FTIR, XPS, and water contact angle test. Heparin was then immobilized onto the activated 316L stainless steel. The heparin surface density was 9.5 μg/cm². Sessile drop water contact angles showed that the heparingrafted surface is even more hydrophilic than the PEG grafted one. The function of grafted heparin was evaluated by antithrombrin III (ATIII) adsorption testing and SEM. The surface with heparin grafting shows better ATIII binding ability and hemocompatibility than the native one.

Objective: To design a novel percutaneous stented valve and model its implantation in the aorta.

Background: The dimensions of stented aortic valve components govern its ability to prevent backflow of blood into the left ventricle. Whilst the theoretical parameters for the best stent performance have already been established, an effective valve model and its suitability along with the stent are lacking.

Methods: This article discusses the design of a stented valve suitable for percutaneous aortic valve replacement. Steps involved in 3D CAD-based geometric modeling of the stented aortic valve and its implantation in the aorta are presented. Conceptual designing of individual components was used to build the total geometric model.

Results: A novel geometric model of percutaneous stented aortic valve was generated. The improved design enhances its performance during and after implantation.

Conclusion: The blunt hooks in the stent model prevent its migration in either direction by getting embedded in the aortic endothelium. This novel stent aortic valve may be of great interest to designers of future bioprosthetic heart valve models, as well as to surgeons involved in minimally invasive valve surgeries.

Vascular support structures are important devices for treating valve stenosis. Large population of patients is treated for valvular disease and the principal mode of treatment is the use of percutaneous valvuloplasty. Stent devices are proving to be an improved technology in minimal invasive cardiac surgery. This technology now accounts for 20% of treatments in Europe. This new technology provides highly effective results at minimal cost and short duration of hospitalization. During the development process, a number of specific designs and materials have come and gone, and a few have remained. Many design changes were successful, and many were not. This paper discusses the physical behavior of a hooked percutaneous aortic valve stent design using finite element analysis using a new Titanium alloy. The analysis performed in this paper may aid in understanding the stent's displacement ranges when subjected to the physiological pressures exerted by the heart and cardiac blood flow during abnormal cardiovascular conditions. It may also help to evaluate the suitability of a new titanium alloy for fabrication purposes.

Stent implantation alters coronary artery hemodynamic and wall shear stress during cardiac cycles. In this study, three-dimensional models were used to analyze the effects of different stent designs and strut thicknesses on the hemodynamic of the artery. The flow was assumed to be pulsatile and stent models were expanded in the artery the same as angioplasty procedure that uses balloon. The data was applied to Fluent-ANSYS package as a UDF MATLAB code. A non-slip condition was applied to the artery walls. The pressure variation in different stents and the wall shear stress distribution were studied. Furthermore, the hemodynamic effects on the flow were investigated for two different thickness values of the same stent design. These results showed that stent implanting is one of the main parameters of pressure drop in the artery. Moreover, the surface of the stent is the location of maximum wall shear stress and the thicker stent strut did not vary this stress much. Our study implies that some design parameters such as thickness affect the hemodynamic factors of blood after stent implantation. Even stent implanting causes re-stenosis in the coronary artery. Using new real models is suggested to investigate new aspects of stent design and related effects on the hemodynamic of coronary arteries.