(Press-News.org) The early diagnosis of certain types of cancer, as well as nervous system diseases such as multiple sclerosis and neuromyelitis optica, may soon be facilitated by the use of a nanometric sensor capable of identifying biomarkers of these pathological conditions.
The nanobiosensor was developed at the Federal University of São Carlos (UFSCar), Sorocaba, in partnership with the São Paulo Federal Institute of Education, Science & Technology (IFSP), Itapetininga, São Paulo State, Brazil. It was originally designed to detect herbicides, heavy metals and other pollutants.
"It's a highly sensitive device, which we developed in collaboration with Alberto Luís Dario Moreau, a professor at IFSP. "We were able to increase sensitivity dramatically by going down to the nanometric scale," said physicist Fábio de Lima Leite, a professor at UFSCar and the coordinator of the research group.
The nanobiosensor consists of a silicon nitride (Si3N4) or silicon (Si) nanoprobe with a molecular-scale elastic constant and a nanotip coupled to an enzyme, protein or other molecule.
When this molecule touches a target of interest, such as an antibody or antigen, the probe bends as the two molecules adhere. The deflection is detected and measured by the device, enabling scientists to identify the target.
"We started by detecting herbicides and heavy metals. Now we're testing the device for use in detecting target molecules typical of nervous system diseases, in partnership with colleagues at leading centers of research on demyelinating diseases of the central nervous system"
The migration from herbicide detection to antibody detection was motivated mainly by the difficulty of diagnosing demyelinating diseases, cancer and other chronic diseases before they have advanced beyond an initial stage.
The criteria for establishing a diagnosis of multiple sclerosis or neuromyelitis optica are clinical (supplemented by MRI scans), and patients do not always present with a characteristic clinical picture. More precise diagnosis entails ruling out several other diseases.
The development of nanodevices will be of assistance in identifying these diseases and reducing the chances of false diagnosis.
The procedure can be as simple as placing a drop of the patient's cerebrospinal fluid on a glass slide and observing its interaction with the nanobiosensor.
"If the interaction is low, we'll be able to rule out multiple sclerosis with great confidence," Leite said. "High interaction will indicate that the person is very likely to have the disease." In this case, further testing would be required to exclude the possibility of a false positive.
"Different nervous system diseases have highly similar symptoms. Multiple sclerosis and neuromyelitis optica are just two examples. Even specialists experience difficulties or take a long time to diagnose them. Our technique would provide a differential diagnostic tool," Leite said.
The next step for the group is to research biomarkers for these diseases that have not been completely mapped, including antibodies and antigens, among others. The group has begun tests for the detection of head and neck cancer.
INFORMATION:
Irvine, Calif., June 23 -- By identifying in spinal fluid how the characteristic mutant proteins of Huntington's disease spread from cell to cell, UC Irvine scientists and colleagues have created a new method to quickly and accurately track the presence and proliferation of these neuron-damaging compounds -- a discovery that may accelerate the development of new drugs to treat this incurable disease.
The researchers added that the cell-to-cell "seeding" property of these mutant proteins seems to be a critical part of the disease's progression. Their findings also advance ...
A rigorous analysis of more than 20,000 medical records concludes that erectile dysfunction drugs, such as Viagra, are not a cause of melanoma, an often deadly form of skin cancer, despite the higher risk for the disease among users of these drugs. A detailed report on the research findings is to be published in the Journal of the American Medical Association online June 23.
The analysis, led by researchers at NYU Langone Medical Center and its Laura and Isaac Perlmutter Cancer Center, of medical records for some 20,235 mostly white men suggests instead that the likely ...
DURHAM, N.C. - Heart attack patients age 65 and older who have reduced heart function might still benefit from implanted defibrillators, according to a Duke Medicine study published in the Journal of the American Medical Association. But fewer than 1 in 10 eligible patients actually get a defibrillator within a year of their heart attacks, the study found.
Advanced age, transitions in care between the hospital and an outpatient clinic, and a mandatory waiting period to get a defibrillator after a heart attack were the most likely factors for low rates of use, according ...
Among Medicare patients who experienced a heart attack from 2007 to 2010, fewer than 1 in 10 eligible patients with low ejection fraction (a measure of how well the left ventricle of the heart pumps blood with each beat) received an implantable cardioverter-defibrillator (ICD) within 1 year after the heart attack, even though ICD implantation was associated with a lower risk of death at 2 years after implantation, according to a study in the June 23/30 issue of JAMA.
More than 350,000 people experience sudden cardiac death in the United States annually. Clinical trials ...
Among men in Sweden, use of erectile dysfunctions drugs with phosphodiesterase type 5 inhibitors was associated with a modest but significant increased risk of malignant melanoma, although the pattern of association raises questions about whether this association is causal, according to a study in the June 23/30 issue of JAMA.
Phosphodiesterase type 5 (PDE5; an enzyme), the target of oral erectile dysfunction (ED) drugs, is part of a pathway that has been implicated in the development of malignant melanoma. This has raised questions whether PDE5 inhibitors used to treat ...
Among extremely preterm infants, early screening for the vascular disorder patent ductus arteriosus before day 3 of life was associated with a lower risk of in-hospital death and pulmonary hemorrhage, but not with differences in other severe complications, according to a study in the June 23/30 issue of JAMA.
The ductus arteriosus is a blood vessel in a fetus that bypasses pulmonary circulation by connecting the pulmonary artery directly to the ascending aorta. It usually closes within 72 hours of birth in most normal-term infants. However, failure to close is common ...
In an analysis of the findings of nearly 80 randomized trials that included about 6,500 participants, there was moderate-quality evidence to support the use of cannabinoids (chemical compounds that are the active principles in cannabis or marijuana) for the treatment of chronic pain and lower-quality evidence suggesting that cannabinoids were associated with improvements in nausea and vomiting due to chemotherapy, sleep disorders, and Tourette syndrome, according to a study in the June 23/30 issue of JAMA.
Medical cannabis refers to the use of cannabis or cannabinoids ...
An analysis of edible medical marijuana products from 3 major metropolitan areas found that many had lower amounts of key substances than labeled, which may not produce the desired medical benefit, while others contained significantly more of a certain substance than labeled, placing patients at risk of experiencing adverse effects, according to a study in the June 23/30 issue of JAMA.
As the use of cannabis (marijuana) for medical purposes has expanded, a variety of edible products for oral consumption has been developed. An estimated 16 percent to 26 percent of patients ...
In a proof-of-concept study, a team led by a Johns Hopkins researcher reports that the vast majority of edible cannabis products sold in a small sample of medical marijuana dispensaries carried labels that overstated or understated the amount of delta-9-tetrahydrocannabinol (THC).
Though the scope of the study was small, the researchers say, the results of the study suggest some medical cannabis patients could be unintentionally overdosing or are being cheated by mislabeled products.
"If this study is representative of the medical cannabis market, we may have hundreds ...
BOSTON, June 23 -- In a Viewpoint published today in the Journal of the Medical Association (JAMA), researchers from the Friedman School of Nutrition Science and Policy at Tufts University and Boston Children's Hospital call on the federal government to drop restrictions on total fat consumption in the forthcoming 2015 Dietary Guidelines for Americans.
Co-authors Dariush Mozaffarian, M.D., Dr.P.H., dean of the Friedman School, and David Ludwig, M.D., Ph.D., director of the New Balance Foundation Obesity Prevention Center at Boston Children's Hospital, highlight a key, ...
