#Microfluidics Technology-Based Lab-on-a-chip Device Could Reduce Cost of Sophisticated Tests for Diseases Rutgers engineers have developed a breakthrough device that can significantly reduce the cost of sophisticated lab tests for medical disorders
and diseases, such as HIV, Lyme disease and syphilis. The new device uses miniaturized channels and valves to replace"benchtop"assays-tests that require large samples of blood
or other fluids and expensive chemicals that lab technicians manually mix in trays of tubes or plastic plates with cup-like depressions."
and clinics everywhere,"said Mehdi Ghodbane, who earned his doctorate in biomedical engineering at Rutgers and now works in biopharmaceutical research and development at Glaxosmithkline.
Ghodbane and six Rutgers researchers recently published their results in the Royal Society of Chemistry's journal, Lab on a Chip.
The lab-on-chip device, which employs microfluidics technology, along with making tests more affordable for patients
and researchers, opens doors for new research because of its capability to perform complex analyses using 90 percent less sample fluid than needed in conventional tests."
''said Martin Yarmush, the Paul and Mary Monroe Chair and Distinguished Professor of biomedical engineering at Rutgers and Ghodbane's adviser.
Until now, animal research on central nervous system disorders, such as spinal cord injury and Parkinson's disease, has been limited because researchers could not extract sufficient cerebrospinal fluid to perform conventional assays."
The discovery could also lead to more comprehensive research on autoimmune joint diseases such as rheumatoid arthritis through animal studies.
The Rutgers team has combined several capabilities for the first time in the device they've dubbed"ELISA-on-a-chip"(for enzyme-linked immunosorbent assay.
#Translational Grant for Interaction Study of Laser radiation with Circulating Tumor Cells and Melanin Nanoparticles University of Arkansas for Medical sciences (UAMS) researcher Vladimir Zharov, Ph d.,D. Sc.
was awarded a $1. 7 million grant by the National Cancer Institute for clinical testing of a new technology called Theranostics,
which is an integration of early diagnosis and treatment of melanoma. Zharov is director of the Arkansas Nanomedicine Center at the UAMS Winthrop P. Rockefeller Cancer Institute and a professor in the UAMS College of Medicine Department of Otolarynology-Head and Neck Surgery.
Zharov has pioneered the development of identifying tumor cellscirculation in the blood stream of melanoma patients by looking directly through the patient veins using a technology called photoacoustic flow cytometry.
This technology uses a special laser that penetrates through the skin and superficial veins and can heat the natural melanin nanoparticles in melanoma circulating tumor cells (CTCS).
The thermal expansion of these nanoparticles generates sound that can be detected with an ultrasound transducer attached to the skin.
He also has developed technology using lasers to destroy the CTCS as they are identified with the photoacoustic methods.
This can improve the detection of CTCS by 1000-fold. he goal of this translational research grant is for patients to benefit from the knowledge obtained during our study of the interaction of laser radiation with circulating tumor cells and nanoparticles
Zharov said. any years ago we discovered that laser-induced high local temperature can evaporate liquid surrounding light-absorbing nanoparticles
and thus create vapor nanobubbles, Zharov said. Fast expansion and collapse of these nanobubbles significantly increases the sound10-50 fold
and mechanically kills CTCS so that it requires just a few laser pulses or even a single pulse without harmful effects on normal cells.
After a comprehensive study of all these phenomena in animal models and recently in pilot trails in humans, Zharov and his team are ready to develop a second generation of his technology to detect CTCS in vivo at the earliest stages of cancer. sing Theranostics
we will focus on the most aggressive form of melanoma, which metastasizes at an early disease stage making treatment extremely difficult,
Zharov said. His team will use new high-pulse-rate lasers, which are focused small tiny ultrasound transducers that convert physical qualities into an electrical signal.
These lasers will be combined with an ultrafast signal acquisition algorithm to increase the sensitivity and minimize errors in perception due to motion that may be induced by patient hand movements.
Natural melanin nanoparticles will be used as biomarkers to diagnose and as targets for therapy. Because not all melanoma cells highly express melanin
especially in early disease stages, the researchers proposed genetic, laser and nanotechnological methods to increase diagnostic and therapeutic efficiency.
The researchers also discovered that many standard medical procedures especially vigorous manipulation of the tumor, certain types of biopsies and surgery can trigger the release of cancer cells from a primary tumor into circulation, increasing CTC counts.
So while some treatments can provide temporary positive effects, in the long term CTCS released during a medical procedure may cause the cancer to metastasize.
To prevent this side effect of treatment, the researchers will use a portable photoacoustic flow cytometer,
which analyzes particles for the real-time control of CTC release, and then eradicate the CTCS by well-timed therapy including nanobubble-based treatment.
A similar approach can be used to monitor the effectiveness of the different types of treatment for cancer by counting the CTCS before, during and after therapy.
The best individualized therapy will lead to a faster and more significant decrease of CTC count,
and hence, decrease deadly metastasis development. Zharov team has demonstrated already that laser-induced nanobubbles significantly decrease the level of CTCS,
leading to a decrease in the chances of cancer spreading to other organs. urther study could determine
whether these new cancer treatments are effective enough to be used alone or if they should be used in conjunction with conventional cancer therapy,
Zharov said. The clinical team will first test a large group of healthy volunteers to make sure the treatment does no harm. urprisingly,
we have limited knowledge of some blood properties during normal physiological processes, and monitoring of healthy volunteers will provide insight on the level of photoacoustic signal needed,
Zharov said. t will help to better distinguish melanoma-associated small changes in photoacoustic signals at early disease stages.
A metastatic tumor or hypothetically even a single tumor cell, while undetectable with existing diagnostic techniques, can release specific markers in blood that can be detected with this technique. his is a completely new concept of early cancer diagnosis,
and melanoma could be the first cancer with metastatic spread that could be treatable by well-timed therapy,
Zharov said. As a result of this project, a commercial portable cost-effective photoacoustic flow cytometer will be developed for broad application with cancers as well as infection and cardiovascular diseases by detection of bacteria, viruses,
infected cells and clots with enhanced diagnostic sensitivity and treatment efficiency. n R01 grant from the National institute of health is very difficult to obtain,
with less than one out of 10 grant applications from researchers throughout the country being funded. Dr. Zharov has two R01 grants funded at this time
and Neck Surgery in the UAMS College of Medicine UAMS is the state only comprehensive academic health center, with colleges of Medicine, Nursing, Pharmacy, Health professions and Public health;
a graduate school; a hospital; a northwest Arkansas regional campus; a statewide network of regional centers;
and seven institutes: the Winthrop P. Rockefeller Cancer Institute, the Jackson T. Stephens Spine & Neurosciences Institute, the Myeloma Institute, the Harvey & Bernice Jones Eye Institute, the Psychiatric Research
Institute, the Donald W. Reynolds Institute on Aging and the Translational Research Institute. It is the only adult Level 1 trauma center in the state.
UAMS has 2, 890 students and 782 medical residents. It is the state largest public employer with more than 10,000 employees,
including about 1, 000 physicians and other professionals who provide care to patients at UAMS, Arkansas Children Hospital, the VA Medical center and UAMS regional centers throughout the state.
Visit www. uams. edu or www. uamshealth. com or find us on Facebook
#Structured Illumination Microscopy and SPA Help Study SPB Duplication in Living Yeast Cells Cellular mitosis depends in part on small organelles that extend spindles to pull apart chromosome pairs.
Before they can perform this and other essential tasks, these tiny cylindrical structures--known as centrioles in animals and spindle pole bodies (SPBS) in yeast--must themselves duplicate.
However, much about this nanoscale process has remained veiled by the limits of current microscopy. Optical approaches cannot resolve objects below certain wavelength limits,
while non-optical approaches like electron microscopy (EM) can only study nonliving cells. Now, a team of researchers from the Stowers Institute for Medical Research and the University of Colorado Boulder has devised a novel optical technique--a combination of structured illumination microscopy (SIM
and single-particle averaging (SPA)--to resolve individual components of SPB duplication in living yeast cells.
In the process, they have uncovered surprising facts in what many once considered well-trodden ground.
"The use of SIM to study SPB structure completely changes the types of questions we can ask and answer,
and it is likely that SIM will work in living cells, "says Sue Jaspersen, Ph d,
which at less than 200 nanometers (nm) in size fall below the wavelength limit of what is observable using visible light.
The research team turned to SIM as an optical alternative. SIM uses a laser-generated field of horizontal lines to project an interference pattern onto a sample.
According to Jay Unruh, Ph d.,a Stowers research advisor and co-author, analyzing these patterns enables researchers to effectively double their resolution."
"For all of its advantages, SIM still involves sifting through a great deal of noise. To deal with this problem,
often with even greater precision than via SIM alone,"says Jaspersen.""We estimate the precision to be in the 10-30 nm resolution range."
"The SPA-SIM technique made up part of a two-color structured illumination microscopy approach that used endogenously expressed fluorescent protein derivatives.
According to Unruh, this study represents the first combined use of SPA with SIM, and one of the first dual-color super-resolution SPA papers.
including"the structure and timing of half-bridge elongation, the composition of the satellite and the formation of the membrane pore."
According to Jaspersen, the SPA-SIM technique is applicable to a wide variety of subjects beyond SPB structure."
. and Mark Winey, Ph d.,at the University of Colorado, Boulder. The study was funded by the Stowers Institute and the National institutes of health (Mark Winey, P01 GM105537;
A common alternative, electron microscopes, can see much smaller objects, but do not work on living cells.
In a study to be published on the elife website on September 15 2015, a team of researchers from the Stowers Institute for Medical Research and the University of Colorado Boulder combined two optical systems in a new way to get around the natural limits of optical microscopes.
One, called structured illumination microscopy (SIM), makes laser-based interference patterns that change based on what they interact with,
doubling the resolution of optical microscopes. The other, single-particle averaging (SPA), brings tiny objects and their locations into sharper focus by averaging many images into one"typical"picture.
#Scientists Genetically Modify White blood cells to Treat Degenerative Neurological disorders As a potential treatment for Parkinson's disease, scientists at the University of North carolina at Chapel hill have created smarter immune cells that produce
and deliver a healing protein to the brain while also teaching neurons to begin making the protein for themselves.
The researchers, led by Elena Batrakova, an associate professor at the UNC Eshelman School of Pharmacy's Center for Nanotechnology in Drug Delivery,
or reverse the course of Parkinson's disease. There are only therapies to address quality of life, such as dopamine replacement,
"Batrakova said.""However, studies have shown that delivering neurotrophic factor to the brain not only promotes the survival of neurons
but also reverses the progression of Parkinson's disease.""In addition to delivering GDNF, the engineered macrophages can"teach"neurons to make the protein for themselves by delivering both the tools and the instructions needed:
Successfully delivering the treatment to the brain is the key to the success of GDNF therapy,
something most medicines cannot do. The reprogrammed cells travel to the brain and produce tiny bubbles called exosomes that contain GDNF.
The work is described in an article published online by PLOS ONE.""By teaching immune system cells to make this protective protein,
we harness the natural systems of the body to combat degenerative conditions like Parkinson's disease, "Batrakova said.
The North carolina Biotechnology Center awarded a $50, 000 Technology Enhancement Grant to the School to help develop the technology into a viable treatment that can be licensed and commercialized."
"said Alexander Kabanov, director of the nanotechnology center.""We will continue our translational efforts at CNDD,
#Platelet-Mimicking Nanoparticles Could Effectively Deliver Drugs to Targeted Sites Nanoparticles disguised as human platelets could greatly enhance the healing power of drug treatments for cardiovascular disease and systemic bacterial infections.
These platelet-mimicking nanoparticles, developed by engineers at the University of California, San diego, are capable of delivering drugs to targeted sites in the body--particularly injured blood vessels,
as well as organs infected by harmful bacteria. Engineers demonstrated that by delivering the drugs just to the areas where the drugs were needed,
these platelet copycats greatly increased the therapeutic effects of drugs that were administered to diseased rats and mice.
The research led by nanoengineers at the UC San diego Jacobs School of engineering, was published online Sept. 16 in Nature."
"This work addresses a major challenge in the field of nanomedicine: targeted drug delivery with nanoparticles,
"said Liangfang Zhang, a nanoengineering professor at UC San diego and the senior author of the study."
"Because of their targeting ability, platelet-mimicking nanoparticles can directly provide a much higher dose of medication specifically to diseased areas without saturating the entire body with drugs."
"The study is an excellent example of using engineering principles and technology to achieve"precision medicine,
"said Shu Chien, a professor of bioengineering and medicine, director of the Institute of Engineering in Medicine at UC San diego,
and a corresponding author on the study.""While this proof of principle study demonstrates specific delivery of therapeutic agents to treat cardiovascular disease and bacterial infections,
it also has broad implications for targeted therapy for other diseases such as cancer and neurological disorders,"said Chien.
The ins and outs of the platelet copycats On the outside, platelet-mimicking nanoparticles are cloaked with human platelet membranes,
which enable the nanoparticles to circulate throughout the bloodstream without being attacked by the immune system. The platelet membrane coating has another beneficial feature:
it preferentially binds to damaged blood vessels and certain pathogens such as MRSA bacteria, allowing the nanoparticles to deliver
and release their drug payloads specifically to these sites in the body. Enclosed within the platelet membranes are made nanoparticle cores of a biodegradable polymer that can be metabolized safely by the body.
The nanoparticles can be packed with many small drug molecules that diffuse out of the polymer core and through the platelet membrane onto their targets.
To make the platelet-membrane-coated nanoparticles, engineers first separated platelets from whole blood samples using a centrifuge.
The platelets were processed then to isolate the platelet membranes from the platelet cells. Next the platelet membranes were broken up into much smaller pieces and fused to the surface of nanoparticle cores.
The resulting platelet-membrane-coated nanoparticles are approximately 100 nanometers in diameter, which is one thousand times thinner than an average sheet of paper.
This cloaking technology is based on the strategy that Zhang's research group had developed to cloak nanoparticles in red blood cell membranes.
The researchers previously demonstrated that nanoparticles disguised as red blood cells are capable of removing dangerous pore-forming toxins produced by MRSA, poisonous snake bites and bee stings from the bloodstream.
By using the body's own platelet membranes the researchers were able to produce platelet mimics that contain the complete set of surface receptors,
antigens and proteins naturally present on platelet membranes. This is unlike other efforts, which synthesize platelet mimics that replicate one or two surface proteins of the platelet membrane."
"Our technique takes advantage of the unique natural properties of human platelet membranes, which have a natural preference to bind to certain tissues
and organisms in the body,"said Zhang. This targeting ability, which red blood cell membranes do not have,
Platelet copycats at work In one part of this study, researchers packed platelet-mimicking nanoparticles with docetaxel,
Researchers observed that the docetaxel-containing nanoparticles selectively collected onto the damaged sites of arteries
platelet-mimicking nanoparticles can also greatly minimize bacterial infections that have entered the bloodstream and spread to various organs in the body.
Researchers injected nanoparticles containing just one-sixth the clinical dose of the antibiotic vancomycin into one of group of mice systemically infected with MRSA bacteria.
"Our platelet-mimicking nanoparticles can increase the therapeutic efficacy of antibiotics because they can focus treatment on the bacteria locally without spreading drugs to healthy tissues
"We hope to develop platelet-mimicking nanoparticles into new treatments for systemic bacterial infections and cardiovascular disease
#Coated Silica Nanoparticles Could be used for Restorative Treatment of Sensitive Teeth Researchers at the University of Birmingham have shown how the development of coated silica nanoparticles could be used in restorative treatment of sensitive teeth
The study, published in the Journal of Dentistry, shows how sub-micron silica particles can be prepared to deliver important compounds into damaged teeth through tubules in the dentine.
The tiny particles can be bound to compounds ranging from calcium tooth building materials to antimicrobials that prevent infection.
Professor Damien Walmsley, from the School of dentistry at the University of Birmingham explained,"The dentine of our teeth have numerous microscopic holes,
When your outer enamel is breached, the exposure of these tubules is really noticeable. If you drink something cold,
while protecting it against further infection that could penetrate the pulp and cause irreversible damage."
"The aim of restorative agents is to increase the mineral content of both the enamel and dentine,
Previous attempts have used compounds of calcium fluoride, combinations of carbonate-hydroxypatite nanocrystals and bioactive glass, but all have seen limited success as they are liable to aggregate on delivery to the tubules.
However, the Birmingham team turned to sub-micron silica particles that had been prepared with a surface coating to reduce the chance of aggregation.
Professor Zoe Pikramenou, from the School of Chemistry at the University of Birmingham, said, "These silica particles are available in a range of sizes, from nanometre to sub-micron,
without altering their porous nature. It is this that makes them an ideal container for calcium based compounds to restore the teeth,
#Novel Nano-Dispenser Systems Uses Less Insecticide to Kill Citrus Greening Bugs Researchers with the University of Florida and several other institutions have found a way in laboratory tests to use
200 times less insecticide and yet still kill as many insects that carry the devastating citrus greening bacterium.
Lukasz Stelinski, an associate professor with UF Department of Entomology and Nematology, used a commercial formulation of imidacloprid,
a standard insecticide used in the industry to kill the Asian citrus psyllid, among many other pests.
Using less insecticide could mean saving tens of thousands of dollars for small growers, a make-or-break figure for those who are struggling with stunted production and less or no profit due to the disease. uring the past 15 years,
an explosion in research in micro and nanotechnologies has led to the development of a variety of techniques that allows control of matter at microscopic levels never before seen,
said Stelinski, who works at the Citrus Research and Education Center, a unit in the University of Florida Institute of food and agricultural sciences. hey have opened a new era in delivery of pesticides through the development of micro and nanosize controlled release systems.
Polymer molecules are being employed for these nano-dispenser systems because scientists can change their size,
depending on the use needed. They are compatible with living organisms, have a low cost and are about 500 times smaller than a human eyelash.
Both synthetic and natural polymers play an essential role in most people lives every day ranging from familiar synthetic plastics,
such as disposable cutlery, to natural biopolymers like DNA and proteins-fundamental to human life. Using insecticides is one of the few ways farmers currently have to treat their groves for greening, also known as Huanglongbing or HLB.
Citrus greening bacterium first enters the tree via the psyllid, which sucks on leaf sap and leaves behind greening bacteria.
The bacteria then move through the tree via the phloem the veins of the tree.
The disease starves the tree of nutrients, damages its roots and the tree produces fruits that are green and misshapen,
unsuitable for sale as fresh fruit or, for the most part, juice. Most infected trees eventually die, and the disease has affected already millions of citrus trees in North america.
It has recently been found twice in California. Citrus greening was detected first in Florida in 2005.
The citrus industry in Florida has lost approximately 100,000 citrus acres and $3. 6 billion in revenues since 2007, according to researchers with UF/IFAS.
Although current methods to control the spread of citrus greening are limited to the removal and destruction of infected trees and insecticide-based management of psyllid populations
UF/IFAS researchers are working to defeat it on a number of fronts, including trying to reduce populations of the psyllid, breeding citrus rootstock that shows better greening resistance,
and testing treatments that could be used on trees. Stelinski team experimented with the nano-dispensers in the lab,
replicating each treatment experiment five times. In the most successful version of the experiment, 80 percent of the psyllids were dead after 10 days.
Researchers also said that less insecticide could have beneficial environmental impacts. Further field tests are necessary to see how the nano-dispensers perform in sunlight
Other members of the team include Wendy Meyer with UF entomology and nematology department at CREC, Pablo Gurman, with the University of Texas at Dallasdepartment of Materials science and engineering,
and Noel Elman, with the Massachusetts institute of technology Institute for Soldier Nanotechnologies o
#Physicists Induce Stable Ferroelectricity in Strontium Titanate Nanosheets A team of physicists has defied conventional wisdom by inducing stable ferroelectricity in a sheet of strontium titanate only a few nanometers thick.
The discovery could forge pathways to find new materials for nanotechnology devices, said Alexei Gruverman,
a University of Nebraska-Lincoln physics and astronomy professor who worked on the research. It also contradicts the expected behavior of ferroelectric materials,
which normally lose stable ferroelectric polarization as they are made thinner. f you make a strontium titanate film very thin,
Gruverman and his team at UNL used piezoresponse force microscopy, a nanoscale testing technique that Gruverman pioneered,
and switchable polarization had occurred in ultrathin films of strontium titanate grown by a University of Wisconsin team led by Chang-Beom Eom.
The work was supported by the National Science Foundation through a grant from the Designing Materials to Revolutionize and Engineer Our Future program.
which is an electrical analog of ferromagnetism, is characterized by a stable electrical polarization which can be switched (reoriented) with the application of an electrical field.
This quality makes ferroelectric materials useful for an array of electronic applications, such as computer memory chips.
However, the materialstendency to lose ferroelectric stability as they become thinner has limited their usefulness in nanoelectronics.
Many scientists have been investigating techniques to create ferroelectric materials that can still be useful at nanometer scale dimensions.
Strontium titanate, often used as an insulating material in dielectric capacitors, isn ordinarily a ferroelectric at room temperature.
It is a perovskite a family member of complex oxide materials with distinctive cubic crystal structures.
Perovskites have long been recognized for a variety of useful physical properties, including superconductivity, ferromagnetism and ferroelectricity.
In recent years, they have been studied for potential use in solar cells. But crystals aren formed always perfectly.
If one out of each 100 strontium ions is missing from the cube-shaped strontium titanate crystal,
it can create polarized nano-sized regions within the crystal. Ordinarily, the material bulk serves to isolate such polar nanoregions in an insulating matrix.
Physicists at the University of Wisconsin, however fabricated epitaxial films of strontium titanate, spread across a substrate of the same material, no thicker than the size of these polar nanoregions.
The electrical boundary conditions in the films drastically changed, forcing the polar nanoregions to interact between themselves
and respond in a cooperative manner to the applied electric field. This allowed for the emergence of switchable and stable polarization,
which the UNL team observed using piezoresponse force microscopy. The effect was tested with mathematical simulations and electrical measurements,
as well as through structural microscopic studies. Gruverman said it is known not yet whether other perovskite materials will exhibit the same qualities. e don know
if this effect is unique to strontium titanate, but we hope that this approach can be extended to other perovskite dielectrics in
which polar nanoregions are controlled by careful engineering of film defect structure, he said. his may provide a path toward devices with reduced dimension where ferroelectricity is coupled to other properties, such as magnetism.
Eom and Gruverman serve as corresponding authors for an article about the discovery published in Science Friday.
and Gruverman is a pioneer in nanoscale studies of ferroelectric materials. A second UNL group involved in these studies,
The paper is authored co by the UNL postdoctoral researcher Haidong Lu and research assistant professor Tula Paudel.
Others involved in the work included Penn State university, Korea Institute of Materials science, Temple University, Pohang University of Science and Technology, University of California-Santa barbara and Boise State university n
Overtext Web Module V3.0 Alpha
Copyright Semantic-Knowledge, 1994-2011