Archive for category: E-News

E-News

Heater-cooler devices blamed for global mycobacterium chimaera outbreak

, /in /by

A global outbreak of Mycobacterium chimaera, an invasive, slow-growing bacterium, is linked to heater-cooler devices (HCD) used in cardiac surgery, according to a study. This study adds interim guidance to recent field reports on the outbreak, providing precautionary recommendations to hospitals and health systems to reduce the risk of infections.

‘It is surprising that a global outbreak like this could go unnoticed for years. This dangerous infection has put many patients at risk all over the world,’ said Rami Sommerstein, MD, of Inselspital, Bern University Hospital in Switzerland, the lead author of the study. ‘Now that we know HCDs are the source, individual action from the different players (healthcare institutions, manufacturers, etc.) is needed to contain the ongoing patient risk. The most important action a hospital can take is to remove contaminated HCDs from the operating room and other critical areas. That is the only way to ensure that patients are protected from this infection moving forward.’

HCDs are stand-alone devices needed for heat exchange in heart-lung machines used in some 250,000 surgeries annually in the U.S., according to the Centers for Disease Control and Prevention. In response to an increasing number of infections, investigators looked into hospital water sources and found M. chimaera in HCD water circuits – specifically, in the LivaNova 3T HCD used in most hospitals around the world. They also found the bacteria in air samples during surgeries with LivaNova HCDs, suggesting transmission through air particles.

To prevent future cases of invasive M. chimaera infections, the researchers made the following recommendations for hospitals and health systems, as well as public health authorities, based on their personal experience with the outbreak:

Ensure strict separation of contaminated HCDs from air of critical medical areas
Educate clinicians on the risks for and dangers associated with M. chimaera
Screen patients who had open heart surgery, heart transplantation or those who were exposed to ventricular assist devices and demonstrate prolonged and unexplained fevers.
M. chimaera is a non-tuberculous mycobacterium that was previously known to cause lung infections. Invasive M. chimaera in cardiac surgery patients is particularly difficult to treat because it requires surgery and prolonged antibiotic therapy.

‘While our understanding of the causes and the extent of the M. chimaera outbreak is growing, several aspects of patient management, device handling and risk mitigation still require clarification,’ said Sommerstein.

Society for Healthcare Epidemiology of America www.shea-online.org/journal-news/press-room/press-release-archives/497-heater-cooler-devices-blamed-for-global-mycobacterium-chimaera-outbreak

Holographic imaging and deep learning diagnose malaria

, /in /by

Duke researchers have devised a computerized method to autonomously and quickly diagnose malaria with clinically relevant accuracy — a crucial step to successfully treating the disease and halting its spread.
In 2015 alone, malaria infected 214 million people worldwide, killing an estimated 438,000.

Malaria’s symptoms can look like many other diseases, and there are simply not enough well-trained field workers and functioning microscopes to keep pace with the parasite. While rapid diagnostic tests do exist, it is expensive to continuously purchase new tests. These tests also cannot tell how severe the infection is by tallying the number of infected cells, which is important for managing a patient’s recovery.

In a new study, engineers from Duke University report a method that uses computer deep learning’ and light-based, holographic scans to spot malaria-infected cells from a simple, untouched blood sample without any help from a human. The innovation could form the basis of a fast, reliable test that could be given by most anyone, anywhere in the field, which would be invaluable in the $2.7 billion-per-year global fight against the disease.

‘With this technique, the path is there to be able to process thousands of cells per minute,’ said Adam Wax, professor of biomedical engineering at Duke. ‘That’s a huge improvement to the 40 minutes it currently takes a field technician to stain, prepare and read a slide to personally look for infection.’
The new technique is based on a technology called quantitative phase spectroscopy. As a laser sweeps through the visible spectrum of light, sensors capture how each discrete light frequency interacts with a sample of blood. The resulting data captures a holographic image that provides a wide array of valuable information that can indicate a malarial infection.

‘We identified 23 parameters that are statistically significant for spotting malaria,’ said Han Sang Park, a doctoral student in Wax’s laboratory and first author on the paper. For example, as the disease progresses, red blood cells decrease in volume, lose haemoglobin and deform as the parasite within grows larger. This affects features such as cell volume, perimeter, shape and centre of mass.

‘However, none of the parameters were reliable more than 90 percent of the time on their own, so we decided to use them all,’ said Park.
‘To be adopted, any new diagnostic device has to be just as reliable as a trained field worker with a microscope,’ said Wax. ‘Otherwise, even with a 90 percent success rate, you’d still miss more than 20 million cases a year.’

To get a more accurate reading, Wax and Park turned to deep learning — a method by which computers teach themselves how to distinguish between different objects. By feeding data on more than 1,000 healthy and diseased cells into a computer, the deep learning program determined which sets of measurements at which thresholds most clearly distinguished healthy from diseased cells.

When they put the resulting algorithm to the test with hundreds of cells, it was able to correctly spot malaria 97 to 100 percent of the time — a number the researchers believe will increase as more cells are used to train the program. Because the technique breaks data-rich holograms down to just 23 numbers, tests can be easily transmitted in bulk, which is important for locations that often do not have reliable, fast internet connections, and that, in turn, could eliminate the need for each location to have its own computer for processing.
Wax and Park are now looking to develop the technology into a diagnostic device through a startup company called M2 Photonics Innovations. They hope to show that a device based on this technology would be accurate and cost-efficient enough to be useful in the field. Wax has also received funding to begin exploring the use of the technique for spotting cancerous cells in blood samples.

Duke University pratt.duke.edu/about/news/spotting-malaria

Rapid test identifies disease pathogens

, /in /by

Researchers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB in Stuttgart are developing a test which rapidly and cost-effectively identifies bacteria, fungi or viruses. It can be carried out directly in situ without laboratory equipment and specialist knowledge. ‘The ImmuStick can even detect pathogens outside the body – on medical devices or in hospital rooms for example. However, the technology would certainly also be of interest for testing human blood for germs or allergies’, says Dr. Anke Burger-Kentischer.
The method works as simply as a pregnancy test. The ImmuStick is a test strip onto which a few drops of fluid are applied. If the fluid contains pyrogens, fragments of pathogens, this is shown by a coloured strip in a viewing window. First of all, human immune receptors sensitive to certain pyrogens are applied to the surface of the stick. These are laboratory-produced immune receptors which are synthesized on the basis of the biological model. During production, at the docking point of the immune receptors to which the pyrogens normally bind, a type of placeholder is mounted which is marked with a dye. When drops of a fluid containing pyrogens are then applied to the test strip, the pyrogens rush to the docking point on the immune receptor. The placeholders marked with the dye migrate with the fluid through the test strip until they are visible in the viewing window. The colour signal thus indicates that pyrogens that have docked on the immune receptors are present.
The ImmuStick project was financed with money from the Discover programme. In this way the Fraunhofer-Gesellschaft is supporting projects for the duration of one year in order to demonstrate the feasibility of a technology. The ImmuStick has passed this test. ‘We were able to show that it works very well for the bacterial pyrogen LPS. Together with industrial partners, we now want to develop it into a product’, says project manager Burger-Kentischer. ‘We are currently testing further immune receptors that are specific for other pyrogens.’
Currently envisaged are applications in the food and pharmaceuticals sector or in medical technology, as a complete absence of germs or pyrogens is required there. In principle, the ImmuStick would also be of interest for blood analysis. Pyrogens in the blood often lead to blood poisoning, sepsis, from which many people still die today, especially weakened intensive care patients. ‘However, blood is a special challenge as it is complex and contains many constituent parts. But in the medium term we are aiming at blood analysis’, says Burger-Kentischer.
As pyrogens also include certain allergy trigger factors, an application here would also be conceivable. In the food and pharmaceutical industries, for example, it is important that products are free of allergens. With the ImmuStick these could be detected quickly, cost-effectively and simply. Costly and laborious laboratory tests would therefore no longer be needed or could be supplemented. At present the IGB researchers are seeking cooperation partners who want to further develop the ImmuStick to make it ready for the market.
Pyrogens become a problem when hygiene is of particular importance – in the food and pharmaceutical industries for example, or on intensive care wards in hospitals. Especially people with weakened immune systems can become severely ill. For this reason, tests are frequently carried out and the surfaces of machines or medical devices are tested for pyrogens using swabs. However, to date these tests have been costly and laborious as pyrogens can only be detected with laboratory equipment. A widely used standard test is the detection of LPS, a structure that is present in the membrane of certain bacteria. At present this test takes up around two hours. Other pyrogens can even only be detected in animal experiment.

Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB http://tinyurl.com/jyrlqct

New test could improve diagnosis of tuberculosis in developing nations

, /in /by

In developing nations, the current test to diagnose tuberculosis (TB) is error-prone, complicated and time-consuming. Furthermore, patients in these resource-limited areas can’t easily travel back to a clinic at a later date to get their results. To make diagnoses simpler, faster and more accurate, chemists have developed a quick and easy diagnostic tool. Field trials of the experimental new test began in June in South Africa, which has a high incidence of TB.
In wealthier countries, a patient suspected of having TB can be examined with a chest X-ray. Or a sample of the patient’s sputum, or saliva, can be sent to a lab for testing by techniques such as polymerase chain reaction (PCR).
But in developing nations with limited resources and spotty access to electricity, patients are often checked for TB with the Ziehl-Neelsen (ZN) test, which was developed in the 1880s. Technicians using this 11-step procedure put a saliva sample on a microscope slide, then dye it and rinse it multiple times. The process takes several hours. Even worse, ‘the ZN test is not very sensitive. It misses some cases of TB, and it gives a lot of false positives,’ says Carolyn R. Bertozzi, Ph.D. These limitations led Bertozzi and her team at Stanford University to develop a new test.
But that wasn’t the researchers’ initial goal when they began studying TB 16 years ago. At the time, they were investigating molecules, known as glycolipids, in the cell walls of the bacteria that cause the disease. Each glycolipid consists of the sugar trehalose linked to a lipid, or fat. The researchers discovered that if they provided slightly modified forms of trehalose to the bacteria, the microbes would metabolize the sugar molecules and integrate them into their glycolipids.
Other researchers showed that the bacteria can take up forms of trehalose in which each sugar is attached to a fluorescent dye molecule. A cell that picks up these sugars glows green. ‘We thought we could use this to detect the bacteria in sputum samples,’ Bertozzi says. Unfortunately, the other researchers’ dye also sticks to other components in saliva, making it tough to distinguish the bacteria.
Bertozzi’s team solved this problem by attaching trehalose to a ‘solvatochromic’ dye that doesn’t glow until it’s incorporated into the cell walls. As a result, there’s no background glow. In addition, the process couldn’t be easier: the technician takes a sputum sample, squirts a little of the dye mixture onto it, and then after an hour looks at it under a microscope to see if anything is glowing.
Even better, only live bacterial cells can metabolize the trehalose/dye molecules. The dyes in the ZN test, however, label both live and dead cells. That means the traditional test can’t determine whether the number of live cells is decreasing, so it can’t be used to tell whether a patient’s treatment is working. Because many strains of TB bacteria are now resistant to the standard treatments, ‘if the drugs aren’t working, you want to switch the patient to the next treatment as quickly as possible so you don’t contribute to drug resistance,’ Bertozzi explains.
The group is now working with a collaborator in South Africa to see how the new test performs in real-world conditions. In the meantime, Bertozzi’s team is studying other fluorescent dyes that could work even better in a TB test. They are also using their current trehalose/dye molecule to explore the molecular structure and physical properties of the cell wall of TB bacteria. That knowledge could shed light on the bacteria’s drug-resistance mechanism, as well as potential new ways to kill the cells.

American Chemical Society http://tinyurl.com/jp7yel4

Progesterone may protect women from worst effects of the flu

, /in /by

In mouse studies, researchers from the Johns Hopkins Bloomberg School of Public Health have found that progesterone – a female sex hormone contained in most forms of hormone-based birth control – appears to stave off the worst effects of influenza infection and, in an unexpected finding, help damaged lung cells to heal more quickly.

The findings suggest that sex hormones have an effect far beyond the reproductive system and that progesterone may one day be a viable flu treatment for women

The World Health Organization reports that more than 100 million young adult women around the world are on progesterone-based contraception. And women of reproductive age are twice as likely as men to suffer from complications related to the influenza virus.

‘Despite the staggering number of women who take this kind of birth control, very few studies are out there that evaluate the impact of contraceptives on how the body responds to infections beyond sexually transmitted diseases,’ says study leader Sabra L. Klein, PhD, an associate professor in the Bloomberg School’s Department of Molecular Microbiology and Immunology. ‘Understanding the role that progesterone appears to play in repairing lung cells could really be important for women’s health. When women go on birth control, they don’t generally think about the health implications beyond stopping ovulation, and it’s important to consider them.’

The World Health Organization (WHO) has already listed hormonal contraceptives as an essential medication because of the profound benefits these compounds can have on women’s health by widening the interval between pregnancies, including decreased rates of maternal mortality and improved outcomes for babies and children.

For their research, Klein and her colleagues placed progesterone implants in female mice and left other mice, also female, without. The mice were then infected with influenza A virus. Both sets of mice became ill, but those with implants had less pulmonary inflammation and better lung function and saw the damage to their lung cells repaired more quickly.

The researchers found that progesterone was protective against the more serious effects of the flu by increasing the production of a protein called amphiregulin by the cells lining the lungs. When the researchers bred mice that were depleted of amphiregulin, the protective effects of progesterone disappeared as well. Klein says she was not surprised that progesterone lessened the inflammation and damage associated with the flu. What she didn’t expect was to find that progesterone also helped induce repair.

When female mice (and possibly humans) get sick with the flu, their natural levels of progesterone fall. Women on hormonal contraceptives – be it a birth control pill, intrauterine device (IUD) or injection – get a steadier level of progesterone, which overrides what the ovaries make naturally or what the virus takes away during infection.

Klein says there is no scientific data to date showing whether progesterone in humans has any relationship to flu severity, since no researchers have asked those questions. Building on this research, Klein says researchers at the Johns Hopkins Center of Excellence for Influenza Research and Surveillance doing flu surveillance have added questions about specific forms of birth control to their questionnaires so they can get a better idea of how this protective effect may work in humans.

Johns Hopkins Bloomberg School of Public Health www.jhsph.edu/news/news-releases/2016/female-sex-hormone-may-protect-women-from-worst-effects-of-the-flu.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feedpercent3A+JHSPHNews+percent28Public+Health+News+Headlines+from+Johns+Hopkinspercent29

Doctors use lung ultrasound to diagnose hidden disorders

, /in /by

Researchers have discovered that ultrasound is a better diagnostic test for early diagnosis of pulmonary embolism and other disorders than current tests.
The study, by Dr. Peiman Nazerian, shows that transthoracic lung ultrasound can detect alternative diagnoses including pneumonia and pleural effusion in lungs more accurately than the commonly used Wells score, as well as detecting early signs of pulmonary embolism.
The Wells score is the most commonly used test to predict the clinical probability of a person developing a pulmonary embolism, or blood clot that travels to their lungs.
‘One of the largest criticisms of the widely used Wells score for estimating likelihood of potentially fatal blood clots in the lung [PE] is the vagary that surrounds the definition of its term, alternative diagnosis more likely than PE,” Jeffrey Kline, vice chair of research in the Department of Emergency Medicine and professor in the Department of Cellular and Integrative Physiology at Indiana University School of Medicine and study author, said in a press release.
‘Most clinicians who believe an alternative diagnosis is more likely than PE cannot name the diagnosis. Nazerian et al, show that lung ultrasound can quickly and non-invasively allow physicians to literally see the identity of something else wrong’ other than blood clots in the lung. This advantage can help them be more confident in deciding not to order expensive testing that causes large doses of radiation exposure to patients.’

UPI http://tinyurl.com/jzleagl

Health diagnosis through bio-signal measuring electrodes on IoT devices

, /in /by

DGIST announced that Professor Kyung-in Jang’s research team from the Department of Robotics Engineering succeeded in developing bio-signal measuring electrodes that can be mounted on Internet of Things (IoT) devices through joint research with a research team led by professor John Rogers of the University of Illinois, USA.

The bio-signal measuring electrodes developed by the research team can be easily mounted on IoT devices for health diagnosis, thus they can measure bio-signals such as brain waves and electrocardiograms without additional analysis and measurement equipment while not interfering or restricting human activities.

Conventional hydro-gel based electrodes required external analysis and measurement devices to measure bio-signals due to their pulpy gel forms, which made their attachment to and detachment from IoT devices instable. In addition, since these electrodes were wet-bonded to the skin, there have been disadvantages that the characteristics of the electrodes deteriorated or their performance decreased when the electrodes were dried in the air over a long period.

In contrast, the electrodes developed by Professor Kyung-in Jang can be easily interlocked as if they are a part of IoT devices for health diagnosis. Also, since they are composed only of polymer and metal materials, they have the advantage of there being no possibility of drying in the air.

Long-term usability with wireless EMG recording. Data captured using a) a hydrogel electrode and b) soft, folded magnetic electrode. Each red triangle indicates a specific point of muscle contraction of the flexor carpi radialis of the forearm.

The bio-signal measurement electrodes developed by the research team consist of a composite material in which a magnetic material is folded with a soft and adhesive polymer, with a conductive electrode material wrapped around the composite material. The conductive electrode material electrically connects the bottom surface touching the skin and the top surface touching the electrode of the IoT device.

Electrodes with this structure reacting to the magnetic field can be easily attached and detached by using the attraction that occurs between the magnet and the electrode mounted on the IoT devices. Then, through the conductive electrode materials that connect the skin and the electrode part of the IoT device, the electric signals generated on the skin can be directly transmitted to the IoT device for health diagnosis.

The research team succeeded in storing and analyzing brain waves (electroencephalogram, EEG), electrocardiograms (ECG), eye movements (electrooculogram, EOG), and limb movements and muscle contractions (electromyogram, EMG) of the wearer for a long period through an experiment in which IoT devices with the electrodes are attached to various parts of the human body.

The bio-signal measurement electrodes can measure the bioelectric signal generated from the skin without loss or noise by using the IoT platform, thus they are expected to be applicable to the medical and healthcare fields since they cannot only measure the electrical signals of the body, but also analyze various forms of bio-signals such as body temperature change, skin change, and in-body ion concentration change.

DGIST en.dgist.ac.kr/site/dgist_eng/menu/508.do?siteId=dgist_eng&snapshotId=3&pageId=429&cmd=read&contentNo=33460

Towards better hip replacements

, /in /by

Some potentially good news for aging Baby Boomers: researchers believe that they have developed a hip replacement that will last longer and create fewer problems for the people who receive them than those currently in use. The secret? An implant that "tricks" the host bone into remaining alive by mimicking the varying porosity of real bones.

Interestingly, the key factor that distinguishes the new implant is that is LESS rather than more solid than those in current use, while still being just as strong.

Damiano Pasini, the man behind the design of the new hip replacement, points at the pyramid-like shapes visible on its surface. The implant is known as a femoral stem and connects the living femur with the artificial hip joint. "What we’ve done throughout the femoral stem is to replicate the gradations of density found in a real femur by using hollowed-out tetrahedra," he explains. "Despite the fact that there are spaces within the tetrahedra, these forms are incredibly strong and rigid so they’re a very efficient way of carrying a load. Just think of the lattice-work in the legs of the Tour Eiffel."

Pasini teaches mechanical engineering at McGill University and first started working on the concept for the implant more than 6 years ago. He smiles ruefully as he pulls earlier versions of the implant down from the shelves in his office to show how far he has come since then. He elaborates:

"So because the implant loosely mimics the cellular structure of the porous part of the surrounding femur, it can "trick" the living bone into keeping on working and staying alive. This means that our implant avoids many of the problems associated with those in current use."

Indeed, the main problem with most implants is that because they are solid, or only porous on the surface, they are much harder and more rigid than natural bone. As a result, the implants absorb much of the stress along with the weight-bearing role that is normally borne by the living femur. Without sufficient stress to stimulate cell formation, the bone material in the living femur then becomes reabsorbed by the body and the bone itself begins to deteriorate and become less dense. This is one of the reasons that many implants become painful and need to be replaced after a time. It also explains why people often have difficulty if they have to have the same hip replaced a second time, because there simply isn’t enough normal, healthy bone to hold the implant in place.

It is a problem that orthopaedic surgeons are seeing more and more frequently.

McGill University www.mcgill.ca/newsroom/channels/news/towards-better-hip-replacements-263893

Scientists apply new imaging tool to common brain disorders

, /in /by

A Yale-led team of researchers developed a new approach to scanning the brain for changes in synapses that are associated with common brain disorders. The technique may provide insights into the diagnosis and treatment of a broad range of disorders, including epilepsy, Alzheimer’s disease, schizophrenia, depression and Parkinson’s disease.
Certain changes in synapses – the junctions between nerve cells in the brain – have been linked with brain disorders. But researchers have only been able to evaluate synaptic changes during autopsies. For their study, the research team set out to develop a method for measuring the number of synapses, or synaptic density, in the living brain.
To quantify synapses throughout the brain, professor of radiology and biomedical imaging Richard Carson and his co-authors combined PET scanning technology with biochemistry. They developed a radioactive tracer that, when injected into the body, binds with a key protein that is present in all synapses across the brain. They observed the tracer through PET imaging and then applied mathematical tools to quantify synaptic density. The researchers used the imaging technique in both baboons and humans. They confirmed that the new method did serve as a marker for synaptic density. It also revealed synaptic loss in three patients with epilepsy compared to healthy individuals.
‘This is the first time we have synaptic density measurement in live human beings,’ said Carson, who is senior author on the study. ‘Up to now any measurement of synaptic density was post-mortem.’
The finding has several potential applications. With this non-invasive method, researchers may be able to follow the progression of many brain disorders, including epilepsy and Alzheimer’s disease, by measuring changes in synaptic density over time. Another application may be in assessing how pharmaceuticals slow the loss of neurons. ‘This opens the door to follow the natural evolution of synaptic density with normal aging and follow how drugs can alter synapses or synapse formation.’

Yale University http://tinyurl.com/hnrz9y8

Non-invasive method to detect bone marrow cancer

, /in /by

For the first time, researchers have shown that using Magnetic Resonance Imaging (MRI) can effectively identify bone marrow cancer (myelofibrosis) in an experimental model. The findings may change the way this disease is diagnosed which is now through invasive bone marrow biopsies.

Myelofibrosis is a slow evolving condition hallmarked by increased myeloid cells and in the case of primary myelofibrosis, with an excessive number of large bone marrow cells called megakaryocytes. The pathology also is characterized by structural abnormality of the bone marrow matrix, which at end-stage manifests in excessive deposition of reticulin fibres and cross-linked collagen in the bone marrow, suppression of normal blood cell development and bone marrow failure. Currently the diagnosis is made via an invasive bone marrow biopsy and histophatology to assess cellularity and reticulin deposition in the marrow.

Researchers at Boston University School of Medicine (BUSM) led by Katya Ravid, PhD, designed and tested whether a T2-weighted MRI could detect bone marrow fibrosis in an experimental model. The group was able to show that an MRI could detect a pre-fibrotic state of the disease with a clear bright signal, as well as progressive myelofibrosis. The investigators proposed that the abundance of large megakaryocytes contribute to the signal, since in T2-weighted MR-images, increased water/proton content, as in increased cellularity, yield high (bright) MR-signal intensity.

This is the first study to evaluate a T2-weighted MRI in an experimental model of myelofibrosis with examination of potential sources of the MRI signal, researchers said. ‘Our study provides proof-of-concept that this non-invasive modality can detect pre-fibrotic stages of the disease,’ said Ravid, professor of medicine and biochemistry at BUSM. ‘It is intriguing to speculate that future pre-biopsy MRI of the human pathology might guide in some cases decisions on if and where to biopsy,’ she added.

Boston University School of Medicine www.bumc.bu.edu/busm/2016/11/14/researchers-propose-non-invasive-method-to-detect-bone-marrow-cancer/

Latest issue of International Hospital

April 2024

Digital edition
All articles Archived issues

Free subscription

View more product news

Get our e-alert

The medical devices information portal connecting healthcare professionals to global vendors

Sign in for our newsletter

Prins Hendrikstraat 1
5611HH Eindhoven
The Netherlands
info@interhospi.com

PanGlobal Media IS not responsible for any error or omission that might occur in the electronic display of product or company data.