MD+DI Online is part of the Informa Markets Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Sitemap


Articles from 2010 In July


New Company Trains Students for Careers in the Medical Device Sector

PrepMD (Braintree, MA) has just graduated its first class of students training for careers in the medical device industry. As reported in the Patriot Ledger, the new company's program offers training in cardiac rhythm management, helping participants to land positions at firms that offer pacemakers and other heart devices. According to the report, more than half of the 16 students who completed the six-month program have already secured full-time jobs with medical device companies.

Developed by Matt O'Neal, formerly of Boston Scientific, and Bob Mattioli, formerly of Tyrx, PrepMD has replicated a cardiophysiology lab at its Braintree office, where students learn basic anatomy, as well as how to interpret EKGs and assist physicians in the operating room. The participants also perform clinical observation in the electrophysiology labs at Boston area hospitals. In addition to on-site instruction, many lectures are given by medical device company representatives.

For the upcoming fall term, more than 300 candidates have submitted applications for the course, which costs a total of $25,000. Currently, the program is not accredited.

Scientists Engineer Artificial Silk Using Bacteria

Microscopic image of 285-kD recombinant spider silk fiber

Finer than human hair, five times stronger by weight than steel, and biocompatible, spider dragline silk is suitable for a variety of biomedical applications such as artificial ligaments and surgical thread. However, because natural dragline silk cannot be easily obtained by farming spiders, scientists are attempting to mass produce artificial silk while maintaining the natural material's properties.

Attempting to do just that are Sang Yup Lee from the Korea Advanced Institute of Science and Technology (KAIST; Daejeon, South Korea), Young Hwan Park from Seoul National University, and David Kaplan from Tufts University (Somerville, MA) Their method is similar to what spiders do themselves: express recombinant silk proteins and then spin them into water-insoluble fibers.

For the successful expression of high-molecular-weight spider silk protein, Lee and his colleagues pieced together the silk gene from chemically synthesized oligonucleotides and then inserted it into the expression host--in this case, Escherichia coli, an industrially safe bacterium that is normally found in the human gut. Initially, the bacterium refused to produce silk protein because of the protein's unique characteristics, such as extremely large size, repetitive nature of the protein structure, and biased abundance of the amino acid glycine.

"To make E. coli synthesize this ultra-high-molecular-weight (as big as 285-kD) spider silk protein having a highly repetitive amino acid sequence, we helped E. coli overcome the difficulties by the system's metabolic engineering," Lee explains. His team boosted the pool of glycyl-tRNA, the major building block of spider silk protein synthesis. "We could obtain appreciable expression of the 285-kD spider silk protein, which is the largest recombinant silk protein ever produced in E. coli. That was really incredible," Xia adds.

But this was only the first step. The KAIST team performed high-cell-density cultures to mass produce the recombinant spider silk protein. Then, the team developed a simple, easy-to-scale-up purification process for the protein. The purified protein can be spun into silk fiber. To study the mechanical properties of the artificial spider silk, the researchers determined tenacity, elongation, and Young's modulus, the three critical mechanical parameters that represent a fiber's strength, extensibility, and stiffness. Importantly, the artificial fiber displayed tenacity of 508 MPa, elongation of 15%, and Young's modulus of 21 GPa, values that are comparable to those of native spider silk.

"We have offered an overall platform for mass production of native-like spider dragline silk," Lee concludes. "This platform would enable us to have broader industrial and biomedical applications for spider silk. Moreover, many other silk-like biomaterials such as elastin, collagen, byssus, resilin and other repetitive proteins have similar features to spider silk protein. Thus, our platform should also be useful for their efficient biobased production and applications."

For a small sampling of Medical Product Manufacturing News articles on the development of silk for medical device applications, see "A New Spin on Silk Could Advance Biomimetics Research," "Buzz Grows Around Insect-Inspired Silk," and "Mimicking Mother Nature."

Silver Antimicrobials: Vygon Case Study

Weighing the Options

“When evaluating antimicrobials, safety was a major consideration,” recalls Alan Martin, Vygon’s training and education director. “Whenever you use antibiotics in devices, there are always objections from the healthcare community because of fears of resistance. But because silver has such a long history of safety, we could ease the minds of clinicians. Furthermore, it is a very adaptable technology with a proven track record across a variety of industries.”

In 2000, Vygon developed a PICC catheter for the European market that featured a silver-based antimicrobial coating. But the company found that whenever a clinician would clean the PICC with alcohol, the antimicrobial coating would be removed and device’s polyurethane material would break down, causing extensive leakage.

Vygon went back to the drawing board and chose an alternative silver-based antimicrobial technology that could be incorporated into the device’s polyurethane structure during the manufacturing process.

“We wanted something that was totally integrated into the product so that if the product was roughly handled the antimicrobial wouldn’t be rubbed away,” Martin says. “Adding the silver-based antimicrobial to the polyurethane turned out to be a simple and low-cost process.”

Getting to Market 

In 2001, Vygon developed the first product in its new line of Multicath Expert antimicrobial CVCs; a three-lumen catheter that featured the new silver-based antimicrobial. Since that time, the company has developed one-lumen, two-lumen, four-lumen and five-lumen CVCs for adult patients, as well as a PICC. They also globally market silicon-cuffed long term catheters featuring an antimicrobial.

Martin notes that the regulatory approval process for antimicrobial products has evolved over the past 10 years. “In the early stages, the process could take a long time since there was some skepticism about the use of antimicrobials in devices,” says Martin. “There was also confusion on whether antimicrobial-protected catheters should be classified as drugs or devices. Today, the process is much simpler because regulatory agencies have a solid view of antimicrobials and already have the answers to their questions.

The Selling Climate and Process 

When selling Vygon’s products, Martin notes that it is a multidisciplinary decision making process since healthcare facilities are integrating antimicrobial-protected devices into their overall infection control plans.

"Unlike the U.S., the rest of the world isn’t currently dealing with issues related to lack of reimbursement for HAIs but they are certainly headed in that direction,” Martin explains. “Healthcare facilities across the globe are focused on infection prevention so we’ve had the greatest success when we can sell our products within an infection control bundle.

"It is a very multidisciplinary decision making process these days. We see infection control, clinicians, materials management, risk management and the nurses who will be heavily involved in using these devices – they are all very important parts of the puzzle,' he says. "We do a lot of education these days, getting healthcare facilities to think about disease control guidelines, whether it is guidelines from the CDC, EDCD or other agencies.”

Looking Ahead

Vygon is now turning its sights to neonatology, where bacterial colonization of indwelling catheters is widespread. The company is starting some early discussions around silver-based antimicrobial catheters for this clinical area.

“It is a very interesting area because no one else has ever done it and we have the capabilities to do it,” says Martin. “I really believe antimicrobials will continue to be an area of development among medical devices because they enable us to offer greater benefits over nontreated devices.”

Return to the main article, "Protecting Devices with Silver-Based Antimicrobials."

Panel Supports Medtronic Implant

Last week FDA voiced concerns about the number of cancer cases seen among patients treated with the Amplify, which uses a protein called recombinant bone morphogenetic protein-2, or rhBMP-2, to promote bone growth. Although FDA is not required to follow the recommendation of the panel, it usually does.

New Wound Dressing Concept Relies on Bacteria's Ability to Commit Suicide

Scientists in the chemistry department at the University of Bath (UK) have demonstrated that a simple vesicle (nanocapsule) system can be used in wound dressings to control bacterial growth and infection. According to the researchers, this "nano-Trojan Horse" material can automatically detect infection and respond to it by releasing an antibiotic into the wound. In addition, the material can change color, alerting medical personnel to the presence of infection.

As reported in Nanowerk, senior lecturer Toby Jenkins and his colleagues have shown that pathogenic bacteria can be used to destroy themselves by releasing toxins that rupture nanocapsules containing an antimicrobial agent. Thus far, the researchers have demonstrated the effectiveness of their system for two pathogenic species of bacteria, P. aeruginosa and S. aureus. The scientists' work is detailed in "A Thin Film Detection/Response System for Pathogenic Bacteria" in the Journal of the American Chemical Society.

Conventional dressings must be removed if the skin becomes infected. In contrast, the Bath scientists' nanocapsule dressing releases antibiotics automatically when the wound becomes infected. Thus, the dressing does not have to be removed to treat a skin infection, reducing the risk of scarring. In addition to reducing treatment costs, this wound dressing will reduce the amount of time required to analyze bacterial infections--a particularly crucial advantage in the case of burns, in which the speedy detection of infection can save lives.

While problems pertaining to vesicle stability, tuning of response, manufacturability, and immunological response remain to be solved, the researchers hope to develop a prototype dressing within the next two to three years.

The following video explains the scientists' approach.
 

This Week In Brief: July 27, 2010

Plasmatreat has celebrated the grand opening of its new, 5000-sq-ft office and technical center based in Elgin, IL. The company specializes in atmospheric pressure plasma surface treatment technology and lays claim to the Openair plasma technology.

In response to growing demand, package specialist Mocon Inc. (Minneapolis) has relocated its corporate headquarters to a new facility in the Twin Cities. Featuring 27% more space than the company's former facility, the new plant will house larger production and laboratory functions for its test and measurement equipment.

Test and measurement technology company Fluke Corp. (Everett, WA) has announced that it is consolidating its six calibration product lines under the name Fluke Calibration. This initiative will unify the company's measurement disciplines, which include electrical, RF, temperature, pressure, flow, and calibration software, and will have its own dedicated Web site.

Lantronix Inc. (Irvine, CA) has announced plans to invest in and support the company's growth in the medical device connectivity market. The company, which provides secure, remote-management data networking technologies, will commit to the industry through hiring dedicated professionals, rebranding, participating in industry events, and drafting white papers, for example.

The International Electronics Manufacturing Initiative (iNEMI; Herndon, VA)), an industry-led consortium, will sponsor a workshop on the technical and regulatory challenges anticipated in the implantable and portable segments of the medical electronics industry. Slated for Sept. 16 and 17 in Berlin, the workshop will focus on identifying the technology challenges and standardization gaps that can best be solved by collaborative efforts by the medical electronics industry.

St. Jude Keeping Its Legal Team Busy

"St. Jude Medical has made significant investments in the interventional cardiology space, including the coronary assessment and more recently the coronary imaging markets,” says Frank Callaghan, president of the St. Jude Medical Cardiovascular Division. “From clinical research to important product advancements, Radi Medical Systems and now St. Jude Medical have contributed considerably to the success of this marketplace. As a company that values the innovations we bring to the marketplace, we intend to protect our intellectual property.”

St. Jude Medical also filed a legal complaint this week alleging that former executive Joseph McCullough violated an employment agreement by leaving the company and joining competitor Medtronic soon after. St. Jude says that McCullough, who was group president of the company's U.S. and international division, had "complete and unfettered access to the company's most sensitive and confidential information" about business development and global operations. One of the juicier bits of information he could have given Medtronic? Details about a program for replacement heart valves inserted without major invasive surgery. Medtronic is currently a player in that market.

Shaking Nanoparticles to the Core Could Aid in Cancer Treatment

The 30-nanometer particle combines a magnetic core with a thin gold shell, analogous to an eggshell, that surrounds but does not touch the core. Credit: Xiaohu Gao, UW

A multifunctional nanoparticle developed by researchers at the University of Washington (UW) combines magnetic properties and photoacoustic imaging to erase background noise in imaging applications. As a result, the researchers state that the new imaging technique allows for more-precise imaging that could someday identify a single cancerous cell as it migrates through the bloodstream to another organ.

Background noise can be high in imaging techniques that do not employ radioactive tracers because the volume of surrounding tissue can overwhelm the signal from the contrast agent, according to the scientists. To address this issue, the researchers created a 30-nm particle that features an iron-oxide magnetic core. A thin gold shell designed to absorb infrared light surrounds the core without direct contact.

Using an external, pulsing magnetic field, the researchers then vibrated the multifunctional nanoprobes by their magnetic cores. They subsequently captured a photoacoustic image and were able to isolate the vibrating pixels with image-processing methods.

"There's only one type of particle that will shake at the frequency of our magnetic field, which is our own particle," Xiaohu Gao, assistant professor of bioengineering, told UW.

The scientists believe that this technology could facilitate molecular imaging. "The resulting multifunctional nanoprobes not only offer contrast for electron microscopy, magnetic resonance imaging, and scattering-based imaging, but, more importantly, enable a new imaging mode, magnetomotive photoacoustic imaging, with remarkable contrast enhancement compared with photoacoustic images using conventional nanoparticle contrast agents," they state in a recent abstract for the journal Nature Communications.

Contact Lenses Lead to Medical Injuries in Kids

Wang’s study shows that 70% of the injuries are caused by ophthalmic devices (including contact lenses and eye glasses), general hospital devices (hospital beds, and catheters for example), and OB-GYN devices.

The statistics were gathered between early 2004 and late 2005 and were based on information gathered from the national database for pediatric injuries. Nearly 145,000 injuries were reported in emergency rooms during this period. About 23% of those injuries were caused by contact lenses, while hypodermic needles accounted for 8%.

Public Meeting: Converged Communications and Healthcare Devices Impact on Regulation

The purpose of this meeting is for the FDA and FCC to gain a better understanding of the convergence of communications technologies and medical devices, the future of wireless health technologies, and the challenges they face. Our goal is to enhance coordination between FDA and FCC for future devices and applications, and to clarify and delineate the respective areas of expertise and jurisdiction between the agencies. This meeting marks the beginning of a process through which the agencies will provide appropriate clarifications in the future based on the input gathered.

For those of you who are curious but unable to attend, a webcast of the meeting is being broadcast at reboot.fcc.gov/live. Questions from the web can be sent to fcc-fdameeting@fcc.gov or submitted via Twitter using #fccfda.