News
Rutgers researchers develop automated robotic device for faster blood testing
Rutgers researchers have created an automated blood drawing and testing device that provides rapid results, potentially improving the workflow in hospitals and other health-related institutions to allow health care practitioners to spend more time treating patients.
A study describing the fully automated device is published online in the journal TECHNOLOGY.
"This device represents the holy grail in blood testing technology," said Martin L. Yarmush, senior author of the study and Paul & Mary Monroe Endowed Chair & Distinguished Professor in the Department of Biomedical Engineering at Rutgers University-New Brunswick. "Integrating miniaturized robotic and microfluidic (lab-on-a-chip) systems, this technology combines the breadth and accuracy of traditional blood drawing and laboratory testing with the speed and convenience of point-of-care testing."
A Rutgers biomedical engineering research team created a device that includes an image-guided robot for drawing blood from veins, a sample-handling module and a centrifuge-based blood analyzer. Their device provides highly accurate results from a white blood cell test, using a blood-like fluid spiked with fluorescent microbeads. The testing used artificial arms with plastic tubes that served as blood vessels. The device could provide rapid test results at bedsides or in ambulances, emergency rooms, clinics and doctors' offices.
Theranos Founder Holmes, Former President Indicted for Fraud
Theranos Inc founder Elizabeth Holmes and the embattled blood-testing company's former president were indicted on charges that they engaged in schemes to defraud investors, doctors and patients, the U.S. Justice Department announced on Friday.
The charges against Holmes, 34, and Ramesh “Sunny” Balwani, 53, were announced shortly after the privately held company said that she was stepping down as its chief executive.
Prosecutors said that Holmes and Balwani used advertising and solicitations to encourage doctors and patients to use its blood testing laboratory services despite knowing the company could not produce accurate and reliable results consistently.
"This conspiracy misled doctors and patients about the reliability of medical tests that endangered health and lives," FBI Special Agent in Charge John Bennett said in a statement.
The indictment also alleged that Holmes and Balwani made numerous misrepresentations about Theranos' financial condition and prospects. Balwani, who worked at Theranos from September of 2009 through 2016, had also served as chief operating officer and was a member of the board.
A New FDA-Approved Test for Predicting Preterm Delivery
According to the March of Dimes, preterm birth occurs in approximately 10% of U.S. pregnancies. Until recently, cervicovaginal fetal fibronectin (fFN) was the only FDA-approved test for predicting preterm delivery in symptomatic women.
Despite its FDA approval, fFN has limited clinical value. A condition with low prevalence, such as preterm delivery, has a low pre-test probability of occurring, hence a negative test result adds little to the assessment of the patient. Thus, a screening test for a low prevalence condition must demonstrate high positive predictive value (PPV) to be useful. The negative predictive value (NPV) of fFN is 99.5%, meaning a negative result is highly predictive that a woman will NOT deliver soon. However, PPV of fFN is only ~17%, meaning that less than 1 in 5 women with a positive test result will proceed to delivery within 7-14 days. For comparison, the PPV of flipping a coin in this population is 4%. Meta-analyses have supported the lack of utility for fFN.
In April 2018, the FDA approved cervicovaginal placental alpha macroglobulin-1 (PAMG-1), (brand name Parto Sure from QIAGEN) as a test for assessing the risk of spontaneous preterm birth in patients with symptoms of preterm labor.
Several recent studies have evaluated PAMG-1 for its ability to predict preterm birth.
Wing, et al. conducted a prospective study of pregnant women from 15 US sites, with signs or symptoms of preterm labor between 24 and 35 weeks of gestation with intact membranes and cervical dilations less than 3 cm (>3 cm generally indicates active labor). They compared the utility of PAMG-1 to fFN. Cervicovaginal PAMG-1 demonstrated similar negative predictive value and improved positive predictive value compared to cervicovaginal fFN.
Similarly, Melchor, et al. conducted a retrospective study of women with preterm contractions presenting to a single maternity hospital in Spain. They compared a one year period during which fFN was used to assess risk of pre-term delivery and a one year period where PAMG-1 was used. Similar to the Melchor study, patients were between 24-34 weeks of gestation with signs or symptoms of preterm labor and had intact membranes and a cervical dilation less than 3 cm.
Both studies show improved positive predictive values for PAMG-1 over fFN. However, both studies reported sensitivities for PAMG-1 of 50%. While this test can certainly be viewed as an improvement over fFN, PAMG-1 will only identify half of the women who will deliver within 7 days. Clearly a better marker to predict pre-term delivery is still needed.
Clinical Chemistry
Blood biomarkers as a diagnostic tool for obstructive sleep apnea
The Dove Medical Press journal, Nature and Science of Sleep, has published a study that highlights the potential use of blood biomarkers as a diagnostic tool for obstructive sleep apnea. The article entitled Use of blood biomarkers to screen for obstructive sleep apnea demonstrates positive clinical trial results that suggest blood tests may be a useful screening tool and potentially superior to current diagnostic methods.
The study, which used male participants, found that concurrent elevations of haemoglobin A1c (HbA1c), C-reactive protein (CRP) and erythropoietin (EPO) indicated that a patient may have obstructive sleep apnea. The study demonstrated that blood biomarkers proved superior to the Epworth Sleepiness Scale (ESS) and other standard screening methods currently used for diagnosis, particularly in non-obese males. These tests were shown to correlate with disease severity and may assist in triaging patients for diagnosis and treatment.
In a statement, the authors said that they anticipated that use of objective blood tests will improve screening accuracy and timely diagnosis, improve patient management, decrease the incidence of diabetes and cardiovascular disease, and decrease healthcare costs.
Transfusion Medicine
Surgical blood transfusions tied to clot risk
A new study of U.S. patients found that nearly 1 percent who received red blood cells before, during or after surgery developed clots in the following month.
Clot risk doubled after one transfusion and increased with additional transfusions—tripling with two and quadrupling after three or more, the findings showed.
"This study demonstrates that there may be additional risks to blood transfusion that are not generally recognized," said lead researcher Dr. Aaron Tobian, director of transfusion medicine at Johns Hopkins University, in Baltimore.
However, the study did not prove cause and effect.
If validated in future studies, the findings suggest a need to evaluate common transfusion practices, added Tobian.
Microbiology
HIV tests give false negative results for up to seven months
People taking a controversial preventative HIV drug could give false negative results for up to seven months, new research suggests.
Tests are unable to pick up the virus in those taking PrEP, a US study found.
Infected people may then have unprotected sex thinking they are HIV free, the researchers warn.
PrEP is approved for people at a high risk of HIV infection, such as those with an affected partner.
Critics claim it encourages sexual promiscuity, which could increase the transmission of other sexually transmitted infections (STIs). As PrEP prevents the HIV virus multiplying, it may cause antibody numbers to rise more slowly.
This could mean it takes longer for a person to produce a sufficient number of antibodies for a test to detect them.
PrEP users are recommended to have HIV tests every three months in case they miss a dose, however, lead author Ivana Parker, from the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, suggests they get tested every four weeks.
The CDC is looking into developing more sensitive HIV tests that detect low antibody levels, the New Scientist reported.
Molecular Genetics
Birth triggered rare, deadly illness in mom until UT Southwestern geneticist solved the mystery
Four days after Jessica Hitt gave birth to her first child, Olivia, the new mother became delirious. She started walking into walls and talking gibberish.
Tests showed dangerously high levels of toxic ammonia in her blood. But why? Nothing in Hitt’s medical history suggested this uncommon disorder.
The doctors treating Hitt were baffled, so they reached out to Dr. Markey McNutt, a clinical geneticist at UT Southwestern Medical Center.
McNutt suspected that Hitt was suffering from a defect in the urea cycle, which is how the body gets rid of excess nitrogen created by the breakdown of protein. Ammonia is a normal byproduct of processing nitrogen in the body. The urea cycle is the way of converting the toxic ammonia into urea, which is flushed out in the urine.
Hitt’s condition began to stabilize after days of intensive treatment, including dialysis and blood transfusions. She was released after a week at UT Southwestern and put on medication to help keep her ammonia levels steady. She continued getting monthly checkups.
In the meantime, though, McNutt wanted to pinpoint the exact genetic defect that had caused her urea cycle disorder. Hitt agreed to take part in a genetic research study that lasted about a year. At the end of the study, McNutt was finally able to explain exactly what happened to his patient.
The problem turned out to be a flaw in Hitt’s genetic coding known as N-acetylglutamate synthase deficiency. In simpler terms, it means the enzyme that is supposed to trigger the first step in Hitt’s urea cycle did not work. But it didn’t cause problems until Hitt had a major health event — the birth of her baby.
Research
New DNA test could end 'trial and error' of antidepressant treatments
A new genetic profile test is bringing personalized medicine into the realm of psychology by determining how individual patients are predisposed to respond to more than 30 different drugs.
Some in the medical community think the test could change the way doctors help patients with depression, who often go through expensive and frustrating periods of “trial and error” with antidepressants before they find a drug that works.
“Everyone is going to want this test as people become more aware of the power of DNA,” said Dr. James Kennedy of the molecular brain science department at Toronto’s CAMH, where he is part of an ongoing study called “IMPACT: Individualized Medicine: Pharmacogenetic Assessment & Clinical Treatment.” He said widespread use of the test would reduce health care cost due to shortened treatment and avoidance of side effects and hospitalizations.
The genetic testing tool is called GeneSight and is offered by Assurex Health, a subsidiary of Myriad Genetics Inc. The test — which is not covered by provincial health plans and costs $1,500 if not administered in a clinical trial — analyzes cells taken from a patient’s saliva or cheek swab to determine how a patient’s body metabolizes drugs and predict how they will react to 33 different medications. The results are categorized into a colour-coded list: green means go, or “use as directed,” yellow means “use with caution,” and red means avoid, or “use with increased caution and with more frequent monitoring.”
Kennedy has tried the method on more than 11,000 patients, he said. The results have been encouraging and they plan to release the data in 2019. “It gets the patient better faster — in four or five weeks — without having to go through all this frustrating trial and error,” he said.
Researchers to trial prostate cancer saliva test
An international team of researchers, led by scientists at The Institute of Cancer Research, London, are planning to trial a novel saliva-based DNA test designed to predict men at risk of developing prostate cancer.
The move follows findings of a study - published in the journal Nature Genetics - involving more than 140,000 men that identified 63 new genetic variations in the DNA code that increase the risk of prostate cancer.
Taken together with more than 100 genetic mutations previously linked to the development of the disease, the researchers have devised a new test designed to predict which men were most at risk of developing it during their lifetime.
According to the researchers, the test identifies 1 percent of men who are at highest risk because they carry several of these genetic variants, and as such are nearly six times more likely to develop prostate cancer than the population average.
Scientists at ICR are now are planning a trial of the DNA test on saliva samples taken in GP practices, to assess whether advice or preventative treatment could reduce cases of prostate cancer among those men found to have the highest inherited risk.
“If we can tell from testing DNA how likely it is that a man will develop prostate cancer, the next step is to see if we can use that information to help prevent the disease,” said Professor Ros Eeles, Professor of Oncogenetics at The ICR.
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