Skin patch technologies could enable clinical laboratories to monitor patients’ vitals and report to medical professionals in real time
Pathologists and clinical laboratory leaders have read many Dark Daily ebriefings on the development of skin patches over the years that do everything from monitoring fatigue in the military to being a complete lab-on-skin technology. Now, researchers at the University of California San Diego (UCSD) have developed a wearable patch that can monitor cardiovascular signals and other various biochemical levels in the body simultaneously.
The researchers believe there is enormous potential for such a patch in helping patients monitor conditions such as hypertension or diabetes. They also foresee a scenario where the patch could be used in settings where vitals must be constantly monitored. They hope to develop future versions of the patch that can detect more biomarkers within the body.
“This type of wearable would be very helpful for people with underlying medical conditions to monitor their own health on a regular basis,” Lu Yin, a PhD student and co-first author of the study, told New Atlas. “It would also serve as a great tool for remote patient monitoring, especially during the COVID-19 pandemic when people are minimizing in-person visits to the clinic,” she added.
Combining Precision Medicine with Telehealth and the Internet of Things
About the size of a postage stamp and consisting of stretchy polymers that conform to the skin, the UCSD patch monitors blood pressure and contains sensors that measure different biochemical levels in the body, such as:
The sensors are carefully arranged on the patch to eliminate interference between the signals, noted a UCSD press release.
In their published research, the UCSD researchers wrote of their new skin patch monitoring device, “Intertwined with concepts of telehealth, the internet of medical things, and precision medicine, wearable sensors offer features to actively and remotely monitor physiological parameters. Wearable sensors can generate data continuously without causing any discomfort or interruptions to daily activity, thus enhancing the self-monitoring compliance of the wearer, and improving the quality of patient care.” (Photo copyright: University of California San Diego.)
“Each sensor provides a separate picture of a physical or chemical change. Integrating them all in one wearable patch allows us to stitch those different pictures together to get a more comprehensive overview of what’s going on in our bodies,” said Sheng Xu, PhD, Principle Investigator, Xu Research Group at UCSD, Assistant Professor in the Department of NanoEngineering Department, and a co-first author of the study, in the press release.
The UCSD researchers developed their skin patch to monitor specific biomarkers that can affect blood pressure.
“Let’s say you are monitoring your blood pressure and you see spikes during the day and think that something is wrong,” co-first author Juliane Sempionatto, PhD, a postdoctoral researcher at California Institute of Technology (Caltech) and co-first author of the study, told New Atlas. “But a biomarker reading could tell you if those spikes were due to an intake of alcohol or caffeine. This combination of sensors can give you that type of information,” she added.
The blood pressure sensor sits near the center of the patch and consists of a set of small transducers welded to the patch via a conductive link. Voltage applied to the transducers send ultrasound waves through the body which bounce off arteries and create echoes that are detected by the sensor and converted into an accurate blood pressure reading.
The chemical sensor releases the drug pilocarpine into the skin to induce sweat and then measures the chemicals contained in the sweat to provide readings of certain biochemical levels.
The glucose sensor located in the patch emits a mild electrical current to the body that stimulates the release of interstitial fluid and then reads the glucose level in that fluid.
“The novelty here is that we take completely different sensors and merge them together on a single small platform as small as a stamp,” Joseph Wang, D.Sc, SAIC Endowed Chair, Distinguished Professor of NanoEngineering, Director of the Center for Wearable Sensors at UCSD, and co-author of the study told New Atlas. “We can collect so much information with this one wearable and do so in a non-invasive way, without causing discomfort or interruptions to daily activity.” (Photo copyright: University of Southern California San Diego.)
Skin Patch Measurements Closely Match Those of Traditional Devices
Test subjects wore the patch on their neck while performing various combinations of the following tasks:
exercising on a stationary bicycle,
eating a high-sugar meal,
drinking an alcoholic beverage, and
drinking a caffeinated beverage.
The results of the measurements taken from the patch closely matched measurements collected by traditional monitoring devices such as a:
For now, the patch must be connected to an external power source which transmits the reading to a counter-top machine, but the researchers hope to create a wireless version in the future.
“There are opportunities to monitor other biomarkers associated with various diseases,” Sempionatto said in the UCSD press release. “We are looking to add more clinical value to this device.”
Other Similar Skin Patch Monitoring Technologies
Though an important breakthrough, the UCSD’s device is not the first skin patch monitor to be developed.
Multiple research and clinical studies are underway that hope to prove the accuracy and safety of wearable devices at detecting and monitoring certain health conditions. It’s a worthy goal.
Skin patches, such as the one created at UCSD, could enable clinical laboratories to provide value-added service to medical professionals and patients alike. Medical labs could potentially monitor skin patch readings in real-time and notify physicians and patients of changes in biomarkers that require attention.
Further, as this technology is developed, it will likely find a ready market with the latest generation of consumers who are more willing than previous generations to buy their own diagnostic tests for home use. These “next-generation” healthcare consumers have demonstrated their willingness to use Apple watches, Fitbits, and similar wearable devices to monitor their condition during exercise and other health metrics.
Pathologists and clinical laboratory managers should not overlook the potential for robust consumer demand to accelerate development and market adoption of such skin patches.
Proof-of-concept research investigates whether photoacoustic imaging can be used in place of traditional tissue staining procedures during cancer surgery to determine if all of the tumor has been removed
Determining where breast cancer ends and healthy tissue begins is a critical part of breast cancer surgery. Surgeons are used to working closely during surgery with anatomic pathologists who generate pathology reports that specify the surgical or tumor margin, an area of healthy tissue surrounding a tumor that also must be excised to ensure none of the tumor is left behind. This helps prevent the need for follow-up surgeries and involves quick work on the part of medical laboratories.
Thus, any technology that renders such a pathology report unnecessary, though a boon to surgeons and patients, would impact labs and pathology groups. However, such a technology may soon exist for surgeons to use during breast cancer surgery.
Assessing Tumor Margin with Light During Surgery
A proof-of-concept study undertaken by researchers at Washington University School of Medicine in St. Louis (WUSTL) and California Institute of Technology (Caltech) has been looking at ways photoacoustic and microscopy technologies could enable surgeons to quickly and accurately assess the tumor margin during breast cancer surgeries. The research suggests it could be possible for surgeons to get answers about critical breast tumor margins without employing a clinical laboratory test.
This new technique based on light and sound uses photoacoustic imaging. The researchers scanned a tumor sample and produced images with enough detail to show whether the tumor was completely removed during surgery, a WUSTL news release explained.
The researchers scanned slices of tumors secured from three breast cancer patients. They also compared their results to stained specimens.
The photoacoustic images matched the stained samples in key features, according to the WUSTL news release. And the new technology produced answers in less time than standard analysis techniques. But more research is needed before photoacoustic imaging is used during surgeries, researchers noted.
“This is proof of concept that we can use photoacoustic imaging on breast tissue and get images that look similar to traditional staining methods without any sort of tissue processing,” Novack added.
A new imaging technique based on light and sound produces images doctors can use to distinguish cancerous breast tissue (below the dotted blue line) from normal tissue more quickly than is currently possible. The new technique (right) produces images as detailed and accurate as traditional methods (left) but in less time, according to the researchers. If such technology were eventually approved for clinical use, it would reduce the need for pathologists to analyze frozen sections while a patient was still in surgery. (Caption and photo copyright: WUSTL/Terence T. W. Wong.)
Once ready, this technology may well change how surgeons and pathologists collaborate to treat breast cancer patients and those with other chronic diseases that include growths that must be excised from the body.
Current Pathology Procedures Take Time, Not Always Useful During Cancer Surgery
At present, standard breast cancer operation procedures involve surgical and pathology teams working simultaneously while the breast cancer patient is in surgery.
Excised tissue is frozen (surrounded by a polyethylene glycol solution), sliced into wafers, stained with a dye, and microscopically analyzed by the pathologist in the clinical laboratory to determine if all cancerous tissue has been removed by the surgeon.
“The procedure takes about 10 to 20 minutes. However, freezing of tissue can result in some distortion of cells and some staining artifact. That is why frozen sections are often preliminary—with a final diagnosis based on routine processing of tissue,” according to LabTestsOnline.
Additionally, fatty breast specimens do not make good frozen sections, which requires surgeons to complete procedures uncertain about whether they removed all of the cancer, the researchers noted.
“Right now, we don’t have a good method to assess margins during breast cancer surgeries,” stated Rebecca Aft, MD, PhD, Professor of Surgery at WUSTL and co-senior study author.
Up to 60% of Breast Cancer Patients Require Follow-up Surgeries
More than 250,000 people in the US are diagnosed with breast cancer each year, and about 180,000 elect to undergo surgery to remove the cancer and preserve healthy breast tissue, WUSTL reported. However, between 20% to 60% of patients learn later they need more surgery to have additional tissue removed when follow-up lab analyses suggest tumor cells were evident on the surface of a tissue sample, Caltech noted in a news release.
“What if we could get rid of the waiting? With three-dimensional photoacoustic microscopy, we could analyze the tumor right in the operating room and know immediately whether more tissue needs to be removed,” noted Lihong Wang, PhD, Professor of Medical Engineering and Electrical Engineering in Caltech’s Division of Engineering and Applied Science. Wang conducted research when he was a Professor of Biomedical Engineering at University of Washington’s School of Engineering and Applied Science.
“Currently, no intraoperative tools can microscopically analyze the entire lumpectomy specimen. To address this critical need, we have laid the foundation for the development of a device that could allow accurate intraoperative margin assessment,” the study authors penned in Science Advances.
What is Photoacoustic Imaging and How Does it Work?
Photoacoustic imaging’s laser pulses create acoustic waves within tissue, which make way for intraoperative images with enough detail to expose cancerous tissue as compared to healthy tissue, explained a Medgadget article.
The graphic above shows elements of the photoacoustic microscopy system for surgical margin imaging developed by researchers at University of Washington School of Medicine in St. Louis and California Institute of Technology. (Photo Credit: Science Advances)
According to the Caltech news release:
· Photoacoustic imaging (also called photoacoustic microscopy or PAM by the researchers) employs a low energy laser that vibrates a tissue sample;
· Researchers measure ultrasonic waves emitted by the vibrating tissue;
· Photoacoustic microscopy reveals the size of nuclei, which vibrate more intensely than nearby material;
· Larger nuclei and densely packed cells characterize cancer tissue.
“It’s the pattern of cells—their growth pattern, their size, their relationship to one another—that tells us if this is normal tissue or something malignant,” said Deborah Novack, MD, PhD, WUSTL Associate Professor of Medicine, Pathology, and Immunology, and co-senior author on the study.
Whether in surgical suites or emergency departments, technological advancements continue to bring critical information to healthcare providers at the point of care, bypassing traditional medical laboratory procedures that cost more and take longer to return answers. Successful development of this technology would create new clinical collaborations between surgeons and anatomic pathologists while improving patient care.
Most pathologists know that CRISPR can permanently repair DNA to eliminate diseases that plague families, but also could be used for less ethical purposes, say experts
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What is speeding the development of gene editing is use of the tool known as CRISPR/Cas9. It is a gene-editing tool that makes it possible to genetically modify DNA for therapeutic purposes. It provides medical scientists the ability to repair damaged genes that cause or predispose individuals to disease. (more…)
The science behind the device is an innovative detection assay of dyes that stain leukocytes so they will fluoresce and enable differentiation of white blood cell subtypes
These medical tests run the full spectrum. They include tests to detect HIV, malaria, pregnancy or male fertility, drug use or Hepatitis C. There are tests to monitor liver function, glucose in diabetics, cholesterol; and provide needle-free CBCs and genetic tests. (more…)
