Perena Gouma, a professor in the UTA Materials Science and Engineering Department, has published an article that describes her invention of a hand-held breath monitor that can detect the flu virus.
Gouma’s device is similar to the breathalysers used by police officers when they suspect a driver of being under the influence of alcohol. A patient simply exhales into the device, which uses semiconductor sensors like those in a household carbon monoxide detector.
The difference is that these sensors are specific to the gas detected, yet still inexpensive, and can isolate biomarkers associated with the flu virus and indicate whether or not the patient has the flu. The device could eventually be available in drugstores so that people can be diagnosed earlier and take advantage of medicine used to treat the flu in its earliest stages. This device may help prevent flu epidemics from spreading, protecting both individuals as well as the public health.
Gouma and her team relied on existing medical literature to determine the quantities of known biomarkers present in a person’s breath when afflicted with a particular disease, then applied that knowledge to find a combination of sensors for those biomarkers that is accurate for detecting the flu. For instance, people who suffer from asthma have increased nitric oxide concentration in their breath, and acetone is a known biomarker for diabetes and metabolic processes. When combined with a nitric oxide and an ammonia sensor, Gouma found that the breath monitor may detect the flu virus, possibly as well as tests done in a doctor’s office.
Gouma’s sensors are at the heart of her breath analyser device.
‘I think that technology like this is going to revolutionize personalized diagnostics. This will allow people to be proactive and catch illnesses early, and the technology can easily be used to detect other diseases, such as Ebola virus disease, simply by changing the sensors,’ said Gouma, who also is the lead scientist in the Institute for Predictive Performance Measurement at the UTA Research Institute.

The University of Texas at Arlington http://tinyurl.com/y7tfoy5e

A new technique developed by researchers at Lawrence Livermore National Lab promises to improve accuracy and lower costs of real-time assessment of kidney function, reports an article published this week by SPIE, the international society for optics and photonics.

The paper explores the use of multimodal autofluorescence and light scattering to evaluate functional changes in the kidneys after ischemic injury. Conditions including accumulated arterial plaque or blood clots restrict the flow of oxygen and glucose to organs, and prolonged periods of such ischemia can compromise function.

In ‘Predictive assessment of kidney functional recovery following ischemic injury using optical spectroscopy,’ the authors report on their evaluation of various optical signatures to predict kidney viability and suggest a noncontact approach to provide clinically useful information in real time.

While other current work in this area uses expensive multiphoton and laser-based techniques, the authors reduced expenses by switching to camera-based imaging.

Currently, there is no real-time tool to measure the degree of ischemic injury incurred in tissue or to predict the return of its function. The inability to decisively determine tissue functional status runs two great risks: that dysfunctional tissue may be transplanted, increasing the morbidity and mortality of the patient; and that much-needed functional kidney tissue may be discarded.

In their study, Rajesh Raman of Lawrence Livermore National Lab and co-authors Christopher Pivetti and Christoph Troppmann of the University of California Davis, Rajendra Ramsamooj of California Northstate University, and Stavros Demos of Lawrence Livermore acquired autofluorescence images of kidneys in vivo under 355, 325, and 266 nm illumination. Light-scattering images were collected at the excitation wavelengths while using a relatively narrow band light centred at 500 nm.

The images were simultaneously recorded using a multimodal optical imaging system. The recorded signals were then analysed to obtain time constants, which were correlated to kidney dysfunction as determined by a subsequent survival study and histopathological analysis.

Analysis of the light-scattering and autofluorescence images suggests that variations in tissue microstructure, fluorophore emission, and blood absorption spectral characteristics, combined with vascular response, contribute to the behaviour of the recorded signals. These are used to obtain tissue functional information and enable the ability to predict post-transplant kidney function.

This information can also be applied to the prediction of kidney failure when visual observation cannot, almost immediately following an injury.

Reviewers of the article suggested other promising applications for future development, and envisioned this approach being used as a screening tool for assessing kidney viability prior to transplant. In particular, they said, these cost-effective screening methods could benefit healthcare in developing countries.

SPIE spie.org/about-spie/press-room/press-releases/optical-spectroscopy-improves-predictive-assessment-of-kidney-function-4-may-2017

Researchers have evaluated the long-term efficacy and safety of long duration dual anti-platelet therapy (L-DAPT) compared to short duration DAPT (S-DAPT) after drug-eluting stent (DES) implantation. The current meta-analysis is the first to compare outcomes between S-DAPT and L-DAPT in a meta-analysis restricted to trials with patient follow-up of 24 months or longer.
DAPT using a combination of aspirin and a P2Y12 inhibitor is used for the prevention of ischemic complications after DES implantation. It is estimated that more than 10 million DES have been implanted globally, however, the optimal duration of DAPT after DES implantation remains unclear.
“A major limitation of most randomized control trials (RCTs) and previous meta-analyses was a short period of follow-up,” stated Abhishek Sharma, MD, of the Division of Cardiovascular Medicine at State University of New York Downstate Medical Center. “Between the small number of stent thrombosis (ST) events due to the low risk of ST with newer generation DES and the possibility that very-late ST events were not captured due to inadequate follow up, individual trials and even previous meta-analysis were probably underpowered to detect a definitive difference in reduction of very-late ST with L-DAPT. This limitation was addressed in our study by pooling data from only those RCTs, which have reported outcomes after a follow up of at least 24 months or longer.”
Researchers identified five RCTs in which 19,760 patients were randomized to S-DAPT (N59,810) and L-DAPT (n59,950), respectively. Compared with L-DAPT, S-DAPT was associated with higher rate of myocardial infarction (MI) (odds ratio [OR] 1.48, 95% confidence interval (CI) [1.04, 2.10]). There were no significant differences between S-DAPT and L-DAPT in terms of all-cause mortality, cardiac mortality, ST, TVR or stroke (OR 0.90, 95% CI [0.73, 1.12]; OR 1.02, 95% CI [0.80, 1.30]; OR 1.59, 95% CI [0.77, 3.27]; OR 0.87 95% CI [0.67, 1.14]; and OR 1.08 95% CI [0.81, 1.46], respectively). However, rate of thrombolysis in myocardial infarction (TIMI) major bleeding was significantly lower with S-DAPT compared to L-DAPT (OR 0.64, 95% CI [0.41, 0.99]).
“Our results support the importance of carefully choosing DAPT durations based on an individual patient’s ischemic and bleeding risks,” Sharma continued. “However, the clinical trials included in the current meta-analysis have mostly used clopidogrel as second agent. With increasing adoption of more potent P2Y12 inhibitors in clinical practice, the relative benefit-to-risk profile of S-DAPT vs L-DAPT using these agents remains to be established in future studies.”

The Society for Cardiovascular Angiography and Interventions
www.scai.org/Press/detail.aspx?cid=c76825de-20ca-4fae-bf48-9416611df29d#.WWP0Q_-GP5Y

A Canadian-led research group has developed and validated a rule that could let half of women with unexplained vein blood clots stop taking blood thinners for life.

Over 1.5 million Canadians will experience a vein blood clot their lifetime, known as venous thrombosis. If part of the clot breaks off and travels to the lungs, it can be fatal. Half of these blood clots happen for no apparent reason, and are known as unexplained or unprovoked clots.

Once an unprovoked vein clot is treated, guidelines recommend that patients take blood thinners for the rest of their lives. If they do not, their risk of having a second clot is 30 to 40 percent in the next 10 years. Taking life-long blood thinners virtually eliminates this risk, but comes at a cost of a 1.2 percent chance of major bleeding per year.

‘Patients can get very anxious trying to balance the risks of the treatment with the risks of another blood clot,’ said Dr. Marc Rodger, senior scientist and thrombosis specialist at The Ottawa Hospital and professor at the University of Ottawa. ‘With this rule we can confidently tell half of the women we see that they are at low risk of having another blood clot. This means they can stop taking blood thinners once their initial clot is treated, sparing them the cost, inconvenience and risks of taking life-long medication.’

The HERDOO2 rule, so named to help physicians remember the criteria, was developed by an international team led by Dr. Rodger and published in 2008. According to the rule, if a woman has one or none of the following risk factors she is at low risk for having another blood clot:

Discoloration, redness or swelling in either leg (HER= Hyperpigmentation, (o)edema or redness)

High levels of a clotting marker (D-dimer) in the blood

Body mass index of 30 kg/m2 or more (Obesity)

Older than age 65

The team could not find factors to identify low-risk men.

The Ottawa Hospital Research Institute www.ohri.ca/newsroom/newsstory.asp?ID=903

A team of engineers and scientists at Caltech and ETH Zurich have developed an artificial skin capable of detecting temperature changes using a mechanism similar to the one used by the organ that allows pit vipers to sense their prey.
The material could be grafted onto prosthetic limbs to restore temperature sensing in amputees. It could also be applied to first-aid bandages to alert health professionals of a temperature increase-a sign of infection-in wounds.
While fabricating synthetic woods in a petri dish, a team led by Caltech’s Chiara Daraio created a material that exhibited an electrical response to temperature changes in the lab. It turned out that the component responsible for the temperature sensitivity was pectin.
‘Pectin is widely used in the food industry as a jellifying agent; it’s what you use to make jam. So it’s easy to obtain and also very cheap,’ says Daraio, professor of mechanical engineering and applied physics in the Division of Engineering and Applied Science.
Chiara Daraio, professor of mechanical engineering and applied physics in the Division of Engineering and Applied Science, explains how the new temperature-sensitive artificial skin works.
Intrigued, the team shifted its attention to pectin and ultimately created a thin, transparent flexible film of pectin and water, which can be as little as 20 micrometers thick (equivalent to the diameter of a human hair). Pectin molecules in the film have a weakly bonded double-strand structure that contains calcium ions. As temperature increases, these bonds break down and the double strands ‘unzip,’ releasing the positively charged calcium ions.
Either the increased concentration of free calcium ions or their increased mobility (likely both, the researchers speculate) results in a decrease in the electrical resistance throughout the material, which can be detected with a multimeter connected to electrodes embedded in the film.
The film senses temperature using a mechanism similar-but not identical-to the pit organs in vipers, which allow the snakes to sense warm prey in the dark by detecting radiated heat. In those organs, ion channels in the cell membrane of sensory nerve fibres expand as temperature increases. This dilation allows calcium ions to flow, triggering electrical impulses.
Existing electronic skins can sense temperature changes of less than a tenth of a degree Celsius across a 5-degree temperature range. The new skin can sense changes that are an order of magnitude smaller and have a responsivity that is two orders of magnitude larger than those of other electronic skins over a 45-degree temperature range.

Caltech http://tinyurl.com/y96975gb