3 July 2018
Low-cost prosthetic foot facilitates natural walking
MIT engineers have developed a simple, low-cost, prosthetic foot that can be tailored for individual patients. By using a patient’s body weight and size, the researchers can tune the shape and stiffness of the prosthetic foot, allowing users to walk with an able-bodied gait.
The engineers estimate that if the foot is manufactured on a wide scale it could cost a lot less than existing products. Current high-tech prosthetic limb designs can cost tens of thousands of dollars, making them unattainable for many amputees.
MIT associate professor of mechanical engineering Amos Winter said: “A common passive foot in the US market will cost $1,000 to $10,000, made out of carbon fibre. Imagine you go to your prosthetist, they take a few measurements, they send them back to us, and we send back to you a custom-designed nylon foot for a few hundred bucks. This model is potentially game-changing for the industry, because we can fully quantify the foot and tune it for individuals, and use cheaper materials.”
The team wanted the mechanics of the foot to relate to how the lower leg moves while the foot is in contact with the ground. To do this, they used an existing dataset containing measurements of steps taken by an able-bodied walker with a given body size and weight. With each step, previous researchers had recorded the ground reaction forces and the changing centre of pressure experienced by a walker’s foot as it rocked from heel to toe, along with the position and trajectory of the lower leg.
Winter and his colleagues then developed a mathematical model of a simple prosthetic foot simulation, which described the stiffness, possible motion, and shape of the future prosthetic. They used the ground reaction forces from the dataset to create the model and predict how a user’s lower leg would translate through a single step.
With the model, they then tuned the stiffness and geometry of the simulated prosthetic foot to produce a lower-leg trajectory that was close to the able-bodied swing.
Winter said: “What’s cool is, this behaves nothing like an able-bodied foot, there’s no ankle or metatarsal joint, it’s just one big structure, and all we care about is how the lower leg is moving through space. Most of the testing was done indoors, but one guy ran outside, he liked it so much. It puts a spring in your step.”
3 july 2018
Researchers develop new test for hepatitis B diagnosis in Africa
An international research team has developed two inexpensive and simple blood tests to aid in the diagnosis of hepatitis B patients living in underprivileged African regions.
Researchers from Imperial College London, Medical Research Council Unit The Gambia at the London School of Hygiene & Tropical Medicine, and the Pasteur Institute in Paris collaborated with additional African and European institutions to develop an accurate diagnostic score called TREAT-B.
The score comprises two blood tests for the precise identification of individuals who urgently need treatment for the hepatitis B virus infection.
One blood test is designed to detect the presence of antigens generated by the virus, while the second test measures enzymes produced by the liver in response to these antigens.
Upon evaluation, the researchers observed that the score is similar in accuracy to current approaches to identify patients requiring immediate treatment. It is said to cost $20.
Imperial College London Department of Surgery & Cancer researcher Dr Maud Lemoine said: “These results show that this simple and inexpensive test could be an accurate way to diagnose patients in need of hepatitis B treatment in countries with limited resources.
“This could potentially help diagnose and subsequently treat thousands of people across Africa.”
The TREAT-B score was developed using data from more than 800 hepatitis B patients under the PROLIFICA (Prevention of Liver Fibrosis and Cancer in Africa) study.
To validate the tests, the team used data from African patients in Senegal, Burkina Faso, Germany, France and the UK. The score was found to be 85% accurate in identifying HBV positive patients requiring treatment and 77% in detecting those who do not need treatment.
While the test is yet to be assessed in larger studies, it is expected to help thousands of patients who need life-saving treatment.
The researchers plan to further develop TREAT-B as a finger-prick test in order to enable faster results.
29 june 2018
Zika detection test taps smartphone technology
Investigators from Brigham and Women’s Hospital (BWH) in the US are developing a new way to rapidly and accurately diagnose Zika virus using mobile health technologies that could potentially be used in resource-limited settings.
The researchers believe the tool could also provide home testing for couples who are trying to conceive, particularly in locations that have a high risk of infection. They have described the new technology in the journal ACS Nano.
BWH principal investigator and corresponding author Dr Hadi Shafiee said: “Zika diagnostics represent an urgent need in many parts of the world. Our goal is to address this unmet clinical need using cell phone-based technology.
“Cell phones have the power to perform complicated analyses, handle image processing, take high-quality images, and are ubiquitous in Zika-afflicted countries. We can leverage this to address outbreaks of infectious disease.”
Shafiee and colleagues have taken an entirely new approach to traditional virus diagnostic methods which rely on the detection of antibodies in a patient’s bloodstream. Instead, they are using nanotechnology to develop a method to detect intact copies of the Zika virus.
The researchers developed tiny platinum nanomotors that target Zika as well as microbeads that can bind the virus. When both components are added to a sample containing Zika, they form a 3D complex that moves in the presence of hydrogen peroxide. This movement can be detected using a smartphone when attached to an inexpensive optical device.
The technology can differentiate between the Zika virus and other closely related viruses through the uniqueness of motion signal. The 3D Zika complex moves rapidly while other non-target viruses cause slower motion which can be easily excluded by the smartphone system.
This approach, known as the nanomotor-based bead-motion cellphone (NBC) system, detected Zika in samples with viral concentrations as low as one particle per microlitre. The team also reports that the NBC system was highly specific and could detect Zika in the presence of other viruses.
Lead author Dr Mohamed Shehata Draz said: “The NBC system has the potential to be used at the point of care for disease detection in both developed and developing countries.
“This is an important way to eliminate the social stress related to Zika virus infection and health problems specifically related to newborns.”
28 june 2018
Researchers develop handheld tool to help diagnose brain injury
A research team at the University of Calgary in Canada is developing a new tool to allow accurate and fast measurement of proteins and small molecules that can indicate brain injuries, including concussion.
The new handheld, smartphone-sized device will contain electrodes which can identify key biomarkers in the blood samples of patients, two hours after a suspected injury. It will only require a small amount of blood to conduct the test.
This polyethylenimine modified graphene-oxide electrochemical immunosensor leverages microfluidic technology to automate the sensing protocol.
It is claimed to be at least 100 times more sensitive compared to other brain injury biomarker approaches that are being currently tested.
The researchers expect the tool to address the unmet diagnostic needs in clinics with limited resources, rural health-care setups, those with a lack of emergency vehicles and those affected by war.
In addition, the device is said to have the potential to enable priority-based injury diagnosis in clinics, while delivering primary interventions, injury assessment and prognosis in hospitals.
University of Calgary Cumming School of Medicine clinical assistant professor Chantel Debert said: “It would aid in diagnosing and determining outcomes, helping to ensure patients get their injury assessed quickly, and their total recovery monitored accurately.
“Currently concussion is diagnosed based on clinical judgment, which is subject to interpretation. We need a more precise and accurate way to detect concussion, as well as a way to predict recovery.”
Being developed under the university’s Integrated Concussion Research Program (ICRP), the diagnostic tool is ready to be advanced into clinical trials.
25 june 2018
Siemens Healthineers introduces new ultrasound system
German medical technology company Siemens Healthineers has introduced a new general imaging ultrasound system called the Acuson Sequoia to enable imaging of different sized patients with consistent clarity.
The new device is equipped with a new high-powered architecture Deep Abdominal Transducer (DAX) and other upgrades to elastography and contrast-enhanced ultrasound.
It can produce penetration of up to 40cm to offer high-resolution imaging adapting to patients’ personal characteristics to enable better diagnosis.
Siemens Healthineers Ultrasound head Robert Thompson said: “Ultrasound imaging has been plagued by variability. Patients’ varied physical characteristics and user-dependent variabilities can impact a clinician’s ability to deliver an accurate diagnosis.
“With the new Acuson Sequoia, Siemens Healthineers provides users with a solution that enables real-time imaging for varying patient types, including those with high BMI, without sacrificing image quality and potentially reducing the need for repeat scans and unclear diagnoses.”
The new Acuson Sequoia system is designed to adapt to the ‘BioAcoustic Variations’ of every patient with different tissue density, stiffness and absorption levels.
It is capable of providing high-resolution InFocus imaging throughout the field of view in real-time, eliminating the need to adjust the focal point of the scan.
Additionally, the BioAcoustic technology also enhances Contrast Enhanced Ultrasound (CEUS) bubble longevity compared to ACUSON Sequoia 512.
This contrast-enhanced ultrasound utilises microbubble-based contrast agents to enhance lesions visualisation and subsequent assessment.
During patient examination, the view time of contrast agents with Acuson Sequoia system is longer providing more time for the clinicians to scan for additional incidental lesions.
22 june 2018
NuSight Medical introduces new device for dry eye treatment
Ophthalmic care company NuSight Medical has introduced a new medical device called the NuLids System to treat dry eyes.
Unveiled at the American Optometric Association meeting in Denver, NuLids is said to improve dry eye conditions by gently stimulating and rejuvenating the Meibomian glands in the eye.
NuSight Medical president and CEO Rob Foster said: “Patients benefit from improved tear film stability, comfort, and lubrication that combat dry eye. Doctors gain an important therapy while helping to build their practice.
“And, because NuLids is sold only through licensed eye care practitioners, doctors are in control of the therapy while patients perform the treatment at home, improving practice efficiency.”
NuSight Medical founder and chairman John Olkowski said that nearly 86% of dry eye patients’ Meibomian gland function are damaged leading to unstable tear film and its premature breakdown.
The NuLids facilitates the production and flow of meibum at the gland reducing signs of dry eye.
At a clinical study, the NuLids System bettered Tear Breakup Time by 65%, while Meibomian Glands Yielding Liquid Secretions improved by 81%.
Most of the patients in the study also reported significant improvement in their dry eye conditions following two weeks of daily usage.
Taking around one minute per day, the NuLids process can be carried out with the in-office procedures performed by eye doctors.
NuSight claimed that the NuLids system is convenient to use without any known side effects.
The company also stated that under the NuLids I and NuLids II clinical studies, nearly 95% of patients surveyed following a 30-day trial were said to be satisfied or very satisfied with the treatment.
21 june 2018
HKBU unveils new device to enable safe growth of neural stem cells
Researchers from Hong Kong Baptist University (HKBU) have developed a device containing a specific nanotechnology layer to enable the in vitro proliferation of neural stem cells (NSCs).
The research team was jointly led by Department of Biology professor Ken Yung Kin-lam and Department of Physics associate professor Dr Jeffery Huang Zhifeng.
This medical device is expected to help in reducing the risk of carcinogenesis or inflammation in stem cell therapy which is used to treat neurodegenerative, chronic systemic diseases and other degenerative joint diseases.
HKBU has already filed for a US patent for this device.
Professor Ken Yung said: “With the global population ageing rapidly, neurodegenerative diseases, such as Alzheimer’s disease and Parkinson’s disease, are regarded as the main threat and burden to global healthcare.
“Recently, scientists have turned their focus on cell replacement therapies, including stem cell therapy, which have shown huge promise in treating neurodegenerative diseases.
“Stem cell therapy is a treatment using stem cells to cultivate new and normal cells, tissues or organs and then transplanted to people to restore physiological function by replacing damaged or dead cells.”
He added that the conventional methods used to grow and differentiate NSCs need multiple additional growth factors in a culture medium.
These culture mediums are specific forms of polypeptides that can regulate various aspects of cellular function, which in turn can encourage cancer cells growth or increase the risk of tumours in vivo following transplantation.
Composed of biocompatible materials, the layer of nanostructure in the new medical device prevents the use of additional growth factors for cultivating cells.
HKBU expects that following proliferation and cell differentiation, the mature cell can become a therapeutic agent for stem cell therapy.
19 june 2018
First trial of robot-assisted retinal surgery is successful
Oxford University researchers have completed the first successful trial of robot-assisted retinal surgery.
The trial, involving 12 patients, was supported by the National Institute for Health Research Oxford Biomedical Research Centre and took place at Oxford’s John Radcliffe Hospital. The results have been published in the Nature Biomedical Engineering journal.
Oxford University signed an agreement with Preceyes, the Dutch medical robotics company that designed the PRECEYES Surgical System, in 2016. It was agreed that a team led by eye surgeon and researcher Professor Robert MacLaren would begin the human clinical trials of the product.
Of the 12 patients in the trial, six were randomly allocated robot-assisted surgery and the other half underwent standard manual surgery to remove a membrane from the back of the eye. The robot allowed the surgeon to perform the procedure with equal or better efficacy than in the traditional manual approach.
In the second phase of the trial, the robot was used to insert a fine needle under the retinas of three patients who needed blood to be dissolved in this location due to age-related macular degeneration. All of these patients experienced an improvement in their vision as a result.
Preceyes chief medical officer Professor Marc de Smet said: “The current trial demonstrated and confirmed the safety and precision of our design. Providing precision, accuracy and stability beyond human capabilities are pre-requisites to push the boundaries of existing surgeries and standardising current procedures.”
In six of the patients, the surgery involved the dissection of the epiretinal membrane and inner limiting membrane over the macula, as well as the injection of a recombinant tissue plasminogen activator under the retina to displace sight-threatening haemorrhage in three patients.
MacLaren said: “This is a huge leap forward for delicate and technically difficult surgery, which in time should significantly improve the quality and safety of this kind of operation. The trial also showed that the robot has great potential for extending the boundaries of what we can currently achieve.
“Our next step will be to use the robotic surgical device for precise and minimally traumatic delivery of a gene therapy to the retina, which will be another first-in-man achievement and is set to commence in early 2019.”