Monday, 22 of September of 2014

Category » Engineering for Health

Silk-Based Surgical Implants an Orthopedic Innovation

silkscrewThe latest silk-inspired innovation from the lab of biomedical engineering Professor David Kaplan is receiving media attention: silk-protein surgical screws that could transform the way we heal broken bones. Researchers from Kaplan’s lab and Beth Israel Deaconess Medical Center published their findings in the journal Nature Communications this March.

Surgical screws and plates, or “fixation devices” are used to repair fractured bones and are often made of metal alloys or synthetic polymers. However, metal implants place undue stress on the bone, are prone to infection, and must be surgically removed from the body once a fracture has healed. Synthetic screws are designed to be absorbed by the body, but they can be difficult to set and may cause inflammation.

The research team manufactured plates and screws from the silk protein produced by the Bombyx mori (B. mori) silkworm cocoons. A silk solution was cured into molds that produced easily machinable plates and screws. The silk screws are self-tapping, an improvement from conventional resorbable screws that require careful drilling of a screw hole before insertion of the hardware. In vivo tests showed the screws remain fixed in the bone at four and eight weeks with notable improvements in the healing and resorbtion process.

Professor Kaplan told BBC News: “The future is very exciting. We envision a whole set of orthopaedic devices for repair based on this – from plates and screws to almost any kind of device you can think of where you don’t want hardware left in the body.”

Some added benefits to the silk technology over metal fixation devices include decreased sensitivity to the cold and zero interference with X-ray technology or metal detectors. “One of the other big advantages of silk is that it can stabilize and deliver bioactive components, so that plates and screws made of silk could actually deliver antibiotics to prevent infection, pharmaceuticals to enhance bone regrowth and other therapeutics to support healing,” says Kaplan.

This research was supported by the National Institutes of Health (EB002520).

More coverage on this story: TuftsNow, New Scientist, The Telegraph, and Popular Science


Tufts University Alumni Association 2014 Senior Award Honorees

Each year, the Tufts University Alumni Association (TUAA) recognizes members of the senior class for academic achievement, participation in campus and community activities, and leadership. Twelve students are chosen from a pool of nominees for the TUAA Senior Award. This year’s cohort of Senior Award Honorees includes two engineering students: Briana Bouchard and Laura Burns.

Briana BouchardBriana Bouchard will graduate with a Bachelor of Science degree in mechanical engineering. Bouchard served as Corporate Relations Chair and Publicity Chair for Tufts Society for Women Engineers, Tufts Admissions Tour Guide and Engineering Panelist, Senior Representative and Academic Chair for the American Society of Mechanical Engineers, Residential Assistant for Tufts University Office of Residential Life. As a researcher, she designed a medical device to assist in the insertion of IV catheters in babies and children, was part of a team that designed an award winning audio speaker, and has researched the use of silk for breast implants for women who have had mastectomies.


Laura BurnsLaura Burns will graduate with a Bachelor of Science degree in biomedical engineering. At Tufts, Burns was a Stern Family Scholar, was on the Dean’s List all semesters, a member of Tau Beta Pi (Engineering National Honor Society), President and Board Member of the Tufts University Engineering Student Council, Secretary and Board Member for Tufts University Society for Women Engineers, Captain of the Varsity Swim Team, and a volunteer at Tufts University Admissions Office. Burns was a research assistant in Assistant Professor Lauren Black’s Lab, where she worked with tissue engineering of cardiac tissue and design of an optical device to measure the thickness of delicate tissues.


Faculty Receive NSF Major Research Instrumentation Grants

semiconductor

Advanced semiconductor made in the Vandervelde REAP lab.

John A. and Dorothy M. Adams Faculty Development Professor Tom Vandervelde received a $1M grant for equipment crucial in the development of solar cells, infrared cameras, high-speed (100+GHz) circuits, lasers, and LED lighting. He received a Major Research Instrumentation award from the National Science Foundation to build a multi-chamber molecular beam epitaxy system, which enables the creation of novel semiconductor materials and devices.

Associate Professor and Chair Kyongbum Lee and colleagues in the Department of Biomedical Engineering received a $338K grant for the acquisitions of a state-of-the-art mass spectrometry (MS) system for a range of metabolomics and proteomics applications. Mass spectrometry has emerged as the technology of choice for workflows seeking to identify, detect, and/or quantify metabolites and other small molecules as well as proteins and peptides in complex biological samples.


Aldridge Wins NIH New Innovator Award

Bree Aldridge

Bree Aldridge, Assistant Professor of Molecular Biology & Microbiology

Assistant Professor Bree Aldridge has received a 2013 National Institutes of Health Director’s New Innovator Award. Aldridge is an assistant professor in molecular biology and microbiology at Tufts University School of Medicine, a member of the Molecular Microbiology and Immunology program faculties at the Sackler School of Graduate Biomedical Sciences at Tufts, and adjunct assistant professor in biomedical engineering. She has been awarded a five-year, $1.5 million grant for her research focused on improving drug treatments for tuberculosis.

Aldridge’s research addresses a major obstacle in controlling tuberculosis, which is the lengthy multi-drug therapy currently required to effectively cure the disease. Due to the prolonged treatment, adherence to the drug therapy can be difficult. In addition, when these drugs are misused or mismanaged, multi-drug resistance can develop. To improve health outcomes for patients, and reduce the emergence of drug-resistant strains of the disease, she hopes to shorten and simplify treatments for tuberculosis. The Aldridge lab includes a multidisciplinary team of researchers who combine molecular approaches with mathematical modeling to study the bacterium that causes tuberculosis.


Kaplan’s Team On Board for Continued Regenerative Medicine Research

Today, the Institute for Regenerative Medicine at Wake Forest University School of Medicine announced that the second phase of the Armed Forces Institute of Regenerative Medicine (AFIRM) project will move ahead with involvement from researchers on Stern Family Professor David Kaplan’s biomedical engineering team. The five-year, $75 million federally funded project focuses on applying regenerative medicine to battlefield injuries.

Anthony Atala, M.D., director of the Wake Forest Institute for Regenerative Medicine, is the lead investigator for AFIRM-II. He will direct a consortium of more than 30 academic institutions, including Tufts School of Engineering, and industry partners.

In the first phase of AFIRM, which began in 2008, Kaplan’s group looked at soft tissue reconstruction and peripheral nerve repair research. During this phase, Kaplan will focus on muscle regeneration.


Engineers Develop Early Warning System for Cholera Epidemics

In two recently published papers, School of Engineering researchers have established new techniques for predicting the severity of seasonal cholera epidemics months before they occur and with a greater degree of accuracy than other methods based on remote satellite imaging. Taken together, findings from these two papers may provide the essential lead time to strengthen intervention efforts before the outbreak of cholera in endemic regions.

Cholera, caused by the bacteria Vibrio cholerae, is rare in the United States and other industrialized nations. However, globally, cholera cases have increased steadily since 2005 and the disease still occurs in many places including Africa, Southeast Asia, and Haiti. According to the World Health Organization, there are an estimated 3–5 million cholera cases every year, more than 100,000 cases are fatal. Image credit: CDC.gov

The team, led by Shafiqul Islam, professor of civil and environmental engineering, used satellite data to measure chlorophyll and algae, organic substances, and flora that also support growth of the cholera bacteria. Using satellite images, the researchers created a “satellite water marker” (SWM) index to estimate the presence of organic matter including chlorophyll and plankton based on wavelength measurements.

In a separate paper published online in the journal Environmental Modeling and Software, ahead of the September 1 print edition, Antarpreet Jutla, EG13, Islam, and Ali Akanda, EG13, showed that air temperature in the Himalayan foothills can also be a factor in predicting spring cholera.

“A Water Marker Monitored by Satellites to Predict Seasonal Endemic Cholera,” Antarpreet Jutla, Ali Shafqat Akanda, Anwar Huq, Abu Syed Golam Faruque, Rita Colwell, and Shafiqul Islam, Remote Sensing Letters, published on line before print June 3, 2013, Vol. 4, No. 8, 822–831.http://dx.doi.org/10.1080/2150704X.2013.802097

The research reported in this paper was supported, in part, from National Institutes of Health (NIH) grants 1RCTW008587-01 and 2R01A1039129-11A2.

“A Framework for Predicting Endemic Cholera Using Satellite Derived Environmental Determinants,” Antarpreet S. Jutla, Ali S. Akanda, Shafiqul Islam, Environmental Monitoring and Software, published online before print http://dx.doi.org/10.1016/j.envsoft.2013.05.008

The research reported in this paper was supported through NIH funding under award number 1RCTW008587-01. Dr. Jutla acknowledges the support from Statler College of Engineering and Mineral Resources, West Virginia University, Morgantown, WV.


Omenetto’s Research Provides Basis for Bionic Ears

Last year, a research effort led by Michael McAlpine, an assistant professor of mechanical and aerospace engineering at Princeton, Naveen Verma, an assistant professor of electrical engineering, and Professor Fiorenzo Omenetto of Tufts University, resulted in the development of a “tattoo” made up of a biological sensor and antenna that can be affixed to the surface of a tooth.

Scientists used 3-D printing to merge tissue and an antenna capable of receiving radio signals. (Credit: Frank Wojciechows

Scientists used 3-D printing to merge tissue and an antenna capable of receiving radio signals. (Credit: Frank Wojciechowski)

A new project, however, is the team’s first effort to create a fully functional organ: one that not only replicates a human ability, but extends it using embedded electronics.

“The design and implementation of bionic organs and devices that enhance human capabilities, known as cybernetics, has been an area of increasing scientific interest,” the researchers wrote in the article which appears in the scholarly journal Nano Letters. “This field has the potential to generate customized replacement parts for the human body, or even create organs containing capabilities beyond what human biology ordinarily provides.

This story appeared as a press release on EurekAlert, May 1, 2013.

 


Levin Lab Looks at Cell Voltage as Cancer Treatment

Professor Michael Levin, in the Department of Biology in the School of Arts and Sciences, and doctoral student Brook Chernet, are exploring how changes in cell voltage affect cellular development and, potentially, cancer treatment.

“We have to get away from the idea that it’s always physical matter that’s at the root of the problem – that there’s a damaged gene, or a chemical toxin,” says Levin, also an adjunct biomedical engineering professor. “It’s not always that.”

Levin and Chernet injected messenger RNA that encodes human oncogenes – genes that can transform normal cells into tumor cells – into tadpoles. Next, they soaked the frog larvae in fluorescent dye. This dye was voltage-sensitive, fluorescing more brightly when the cell polarization was greater.

In Michael Levin's lab, fluorescence is used to highlight cellular development in tadpoles.  (Credit: Brook Chernet)

In Michael Levin’s lab, fluorescence is used to highlight cellular development in tadpoles. (Credit: Brook Chernet)

Levin and Chernet separated out tadpoles exhibiting a dark patch of low fluorescence. They found that, over several days, such patches of lowered polarization nearly always developed into tumors, confirming the link between cell polarization and cancer.

Cells become polarized when there is an imbalance of the positive and negative ions that flow in and out of cells through channels in cell membranes. But polarization itself regulates the operation of so-called transporter proteins, which pump signalling molecules through the channels. Through their experiments, Levin and Chernet have found that a lowered polarization inhibits the function of a transporter protein that draws in the signalling molecule butyrate, which, through various enzymes, controls the expression of growth genes. With less butyrate in the cell, these genes are free to instigate abnormally high, cancerous growth.

As a next step, Levin and Chernet split their oncogene-injected tadpoles into two groups. One group received injections of messenger RNA that encodes proteins for new ion channels. The new ion channels drew more negative ions into the tadpole cells, thereby increasing the cells’ polarization. The injected group of tadpoles did not develop nearly so many tumors as the untreated group, demonstrating that polarization is indeed a way to reign in tumors – at least in tadpoles (Dis. Model Mech. 6 595). To pave the way for clinical trials, Levin and Chernet will now have to show that the same results can be found in mammals.

This article was originally published in the July 2013 issue of Physics World magazine, a special issue on the physics of cancer. For a limited time only, you can download a PDF of the issue free of charge from physicsworld.com.

 

 


Poor Infrastructure Could Lead to Unsafe Drinking Water, Islam Says

River Mountains Water Treatment Facility (Credit: snwa.com)

River Mountains Water Treatment Facility (Credit: snwa.com)

Professor Shafiqul Islam of the Department of Civil and Environmental Engineering told CNBC.com the poor state of the nation’s infrastructure could lead to unsafe drinking water if not addressed.

“This is serious, and if it’s not fixed, we could see a breakout of diseases from unsafe water,” Islam told CNBC.

The Environmental Protection Agency released a report in April (“Drinking Water Infrastructure Needs Survey and Assessment“) saying the U.S. water infrastructure would need $384 billion in upgrades from 2011 through 2030.

“Besides the dangerous threat of disease from contaminated water, the economic impact from not upgrading the system is serious,” said Islam, also the director of Tufts Water Diplomacy | IGERT doctoral program.

Exterior of the River Mountains Water Treatment Facility (Credit: SNWA.com)

Exterior of the River Mountains Water Treatment Facility (Credit: SNWA.com)

Islam says that some cities, such as Las Vegas, are exemplars of addressing infrastructure issues to provide safe drinking water.

According to the Southern Nevada Water Authority (SNWA) nearly 90 percent of the region’s drinking water comes from Lake Mead and is treated in two water treatment facilities. SNWA’s River Mountains Water Treatment facility can treat up to 300 million gallons of water per day, but it was designed to expand to meet Southern Nevada’s needs. In the future, the River Mountains facility will be able to treat up to 600 million gallons of water a day.

This story was first reported at CNBC.com, June 14, 2013.


Xu Named Pew Scholar in Biomedical Sciences

 Assistant professor of biomedical engineering Qiaobing Xu was recently named a Pew scholar for his work in nanotechnology related to tissue regeneration. (Credit: Kelvin Ma/Tufts University)

Assistant Professor of biomedical engineering Qiaobing Xu was named a Pew scholar for his work in nanotechnology related to tissue regeneration. (Credit: Kelvin Ma/Tufts University)

Assistant Professor Qiaobing Xu in the Department of Biomedical Engineering was named a Pew Scholar in Biomedical Sciences by the Pew Charitable Trusts. The highly competitive program, whose past winners have included Nobel Prize winners, MacArthur Fellows and recipients of the Albert Lasker Basic Medical Research Award, identifies talented researchers in medicine or biomedical sciences. Xu’s work focuses on nanotechnology for biomedical uses. He will receive $240,000 over four years to advance his research.

Xu’s research delves into tissue engineering and nanomedicine. His lab has pioneered the use of nature-derived nanostructured tissue—decellularized tendon— as a source of biomaterials and works to engineer these materials through a combination of tissue sectioning, multilayer stacking and rolling into structures with innovative biomedical functions.

This press release first appeared in Tufts Now, June 13, 2013.