How To Track Blood Flow In Tiny Vessels

Scientists have designed gold nanoparticles, no bigger than 100 nanometres, which can be coated and used to track blood flow in the smallest blood vessels in the body. By improving our understanding of blood flow in vivo the nanoprobes represent an opportunity to help in the early diagnosis of diseaseLight microscopy is a rapidly evolving field for understanding in vivo systems where high resolution is required. It is particularly crucial for cardiovascular research, where clinical studies are based on ultrasound technologies which inherently have lower resolution and provide limited information.

The ability to monitor blood flow in the sophisticated vascular tree (notably in the smallest elements of the microvasculaturecapillaries) can provide invaluable information to understand disease processes such as thrombosis and vascular inflammation. There are further applications for the improved delivery of therapeutics, such as targeting tumours.

Currently, blood flow in the microvasculature is poorly understood. Nanoscience is uniquely placed to help understand the processes happening in the micron-dimensioned vessels. Designing probes to monitor blood flow is challenging because of the environment; the high protein levels in plasma and the high red blood cell concentrations are detrimental to optical imaging. Conventional techniques rely on staining red blood cells, using organic dyes with short-lived usage due to photobleaching, as the tracking motif. The relatively large size of the red blood cells (7-8 micrometres), which are effectively the probes, limits the resolution in imaging and analysis of flow dynamics of the smallest vessels which are of a similar width. Therefore, to have more detailed resolution and information about the blood flow in the microvasculature, even smaller probes are required.

The key to these iridium-coated nanoparticles lies in both their small size, and in the characteristic luminescent properties. The iridium gives a luminescent signal in the visible spectrum, providing an optical window which can be detected in blood. It is also long-lived compared to organic fluorophores, while the tiny gold particles are shown to be ideal for tracking flow and detect clearly in tissues“, explains Professor Zoe Pikramenou, from the School of Chemistry at  the University of Birmingham.

The findings have been published in the journal Nanomedicine.

Source: https://www.birmingham.ac.uk/

How To Prevent Metastasis In Pancreatic Cancer

UCLA scientists have unlocked an important mechanism that allows chemotherapy-carrying nanoparticles—extremely small objects between 1 and 100 nanometers (a billionth of a meter)—to directly access pancreatic cancer tumors, thereby improving the ability to kill cancer cells and hence leading to more effective treatment outcome of the disease. The researchers also confirmed the key role of a peptide (an extremely small protein) in regulating vascular access of the nanoparticle to the cancer site.

The discovery is the result of a two-year study co-led by Drs. Huan Meng and André Nel, members of UCLA‘s Jonsson Comprehensive Cancer Center and the UCLA California NanoSystems Institute. The findings are important as they demonstrate how the delivery of chemotherapy to pancreatic cancer can be improved significantly through the use of smart-designed nanoparticle features.

Pancreatic ductal adenocarcinoma is generally a fatal disease, with a five-year survival rate of less than 6 percent. The introduction of nanocarriers as delivery vehicles for common chemotherapy agents such as the drug irinotecan, has led to improved survival of patients with this disease. However, the reality is that nanocarriers may not always reach their intended target in sufficient numbers because of a constraint on their ability to transit through the blood vessel wall at the tumor site, leading the encapsulated drugs to be diverted or lost before they can deliver their payload.

silica nanoparticle

A key challenge for scientists is how to help nanoparticles travel to and be retained at tumor sites. This can be accomplished by custom-designed or engineered nanoparticles that overcome common challenges, such as the presence of a dense tissue surrounding the pancreas cancer cells. Prior research has identified a major vascular access mechanism that relies on a vesicle transport system, which can be turned with a peptide called iRGD in the blood vessel wall. iRGD is therefore potentially useful to optimize the delivery of cancer drugs by the nanoparticle to the tumor.

The UCLA research team designed a nanoparticle comprised of a hollow silica core surrounded by a lipid bilayer to enhance the delivery of irinotecan in an animal model with pancreatic cancer. The invention is called a silicasome. The researchers proposed that the therapeutic benefit of the irinotecan containing nanoparticles may be enhanced when combined with the injection of iRGD. The investigators used the nanoparticle plus the iRGD to deliver irinotecan in a robust animal model for pancreatic cancer that closely mimics human disease.

The study is published online in the Journal of Clinical Investigation.

Source: http://www.cancer.ucla.edu/

Shape-shifting Molecular Robots

A research group at Tohoku University and Japan Advanced Institute of Science and Technology has developed a molecular robot consisting of biomolecules, such as DNA and protein. The molecular robot was developed by integrating molecular machines into an artificial cell membrane. It can start and stop its shape-changing function in response to a specific DNA signal.

This is the first time that a molecular robotic system has been able to recognize signals and control its shape-changing function. What this means is that molecular robots could, in the near future, function in a way similar to living organisms.

Using sophisticated biomolecules such as DNA and proteins, living organisms perform important functions. For example, white blood cells can chase bacteria by sensing chemical signals and migrating toward the target. In the field of chemistry and synthetic biology, elemental technologies for making various molecular machines, such as sensors, processors and actuators, are created using biomolecules. A molecular robot is an artificial molecular system that is built by integrating molecular machines. The researchers believe that realization of such a system could lead to a significant breakthrough – a bio-inspired robot designed on a molecular basis.

molecular robot

The molecular robot developed by the research group is extremely small – about one millionth of a meter – similar in size to human cells. It consists of a molecular actuator, composed of protein, and a molecular clutch, composed of DNA. The shape of the robot’s body (artificial cell membrane) can be changed by the actuator, while the transmission of the force generated by the actuator can be controlled by the molecular clutch. The research group demonstrated through experiments that the molecular robot could start and stop the shape-changing behavior in response to a specific DNA signal.

The findings were published in Science Robotics.

Source: http://www.tohoku.ac.jp/

How To Prevent Heart Attacks, Strokes

As men and women grow older, their chances for coronary heart disease also increase. Atherosclerosis is a condition in which plaque builds up inside the arteries, which can lead to serious problems, including heart attacks, strokes or even death. Now, researchers at the University of Missouri (MU)  have found that Insulin-like Growth Factor-1 (IGF-1), a protein that is naturally found in high levels among adolescents, can help prevent arteries from clogging. They say that increasing atherosclerosis patients’ levels of the protein could reduce the amount of plaque buildup in their arteries, lowering their risk of heart disease.

heart

The body already works to remove plaque from arteries through certain types of white blood cells called macrophages,” said Yusuke Higashi, PhD, assistant research professor in the Division of Cardiovascular Medicine at the MU School of Medicine and lead author of the study. “However, as we age, macrophages are not able to remove plaque from the arteries as easily. Our findings suggest that increasing IGF-1 in macrophages could be the basis for new approaches to reduce clogged arteries and promote plaque stability in aging populations.”

In a previous study, Higashi and Patrice Delafontaine, MD, the Hugh E. and Sarah D. Stephenson Dean of the MU School of Medicine, examined the arteries of mice fed a high-fat diet for eight weeks. IGF-1 was administered to one group of mice. Researchers found that the arteries of mice with higher levels of IGF-1 had significantly less plaque than mice that did not receive the protein. Since the macrophage is a key player in the development of atherosclerosis, the researchers decided to investigate potential anti-atherosclerosis effects of IGF-1 in macrophages. The team also found that the lack of IGF-1 action in macrophages changed the composition of the plaque, weakening its strength and making it more likely to rupture and cause a heart attack.

Source: http://medicine.missouri.edu/

How To Prevent Alzheimer’s

Researchers from Imperial College London (ICL) have prevented the development of Alzheimer’s disease in mice by using a virus to deliver a specific gene into the brain. The early-stage findings by scientists open avenues for potential new treatments for the disease. In the study, published in the journal Proceedings of the National Academy of Sciences, the team used a type of modified virus to deliver a gene to brain cells.

Previous studies by the same team suggest this gene, called PGC1 – alpha, may prevent the formation of a protein called amyloid-beta peptide in cells in the lab. Amyloid-beta peptide is the main component of amyloid plaques, the sticky clumps of protein found in the brains of people with Alzheimer’s disease. These plaques are thought to trigger the death of brain cellsAlzheimer’s disease affects around 520,000 people in the UK. Symptoms include memory loss, confusion, and change in mood or personality. Worldwide 47.5 million people are affected by dementia – of which Alzheimer’s is the most common form. There is no cure, although current drugs can help treat the symptoms of the disease.

Dr Magdalena Sastre, senior author of the research from the Department of Medicine at Imperial, hopes the new findings may one day provide a method of preventing the disease, or halting it in the early stages.

alzheimer_s_disease_vs_normal-spl

She explained: “Although these findings are very early they suggest this gene therapy may have potential therapeutic use for patients. There are many hurdles to overcome, and at the moment the only way to deliver the gene is via an injection directly into the brain. However this proof of concept study shows this approach warrants further investigation.”

The modified virus used in the experiments was called a lentivirus vector, and is commonly used in gene therapy explained Professor Nicholas Mazarakis, co-author of the study from the Department of Medicine: “Scientists harness the way lentivirus infects cells to produce a modified version of the virus, that delivers genes into specific cells. It is being used in experiments to treat a range of conditions from arthritis to cancer. We have previously successfully used the lentivirus vector in clinical trials to deliver genes into the brains of Parkinson’s disease patients.

Source: http://www3.imperial.ac.uk/

Osteoarthritis: NanoParticles Stop Destruction Of Cartilage

Osteoarthritis is a debilitating condition that affects at least 27 million people in the United States, and at least 12 percent of osteoarthritis cases stem from earlier injuries. Over-the-counter painkillers, such as anti-inflammatory drugs, help reduce pain but do not stop unrelenting cartilage destruction. Consequently, pain related to the condition only gets worse. Now, researchers at Washington University School of Medicine in St. Louis have shown in mice that they can inject nanoparticles into an injured joint and suppress inflammation immediately following an injury, reducing the destruction of cartilage.

osteoarthritisResearchers at Washington University School of Medicine in St. Louis have found that injecting nanoparticles into an injured joint can inhibit the inflammation that contributes to the cartilage damage seen in osteoarthritis. Shown in green is an inflammatory protein in cartilage cells. After nanoparticles are injected, the inflammation is greatly reduced

 

I see a lot of patients with osteoarthritis, and there’s really no treatment,” said senior author Christine Pham, MD, an associate professor of medicine. “We try to treat their symptoms, but even when we inject steroids into an arthritic joint, the drug only remains for up to a few hours, and then it’s cleared. These nanoparticles remain.

Frequently, an osteoarthritis patient has suffered an earlier injury — a torn meniscus or ACL injury in the knee, a fall, car accident or other trauma. The body naturally responds to such injuries in the joints with robust inflammation. Patients typically take drugs such as acetaminophen and ibuprofen, and as pain gets worse, injections of steroids also can provide pain relief, but their effects are short-lived.

In this study, the nanoparticles were injected shortly after an injury, and within 24 hours, the nanoparticles were at work taming inflammation in the joint. But unlike steroid injections that are quickly cleared, the particles remained in cartilage cells in the joints for weeks.

The nanoparticles used in the study are more than 10 times smaller than a red blood cell, which helps them penetrate deeply into tissues. The particles carry a peptide derived from a natural protein called melittin that has been modified to enable it to bind to a molecule called small interfering RNA (siRNA). The melittin delivers siRNA to the damaged joint, interfering with inflammation in cells.

Source: https://source.wustl.edu/

Could Nanotechnology End Hunger?

Each year, farmers around the globe apply more than 100 million tons of fertilizer to crops, along with more than 800,000 tons of glyphosate, the most commonly used agricultural chemical and the active ingredient in Monsanto’s herbicide Roundup. It’s a quick-and-dirty approach: Plants take up less than half the phosphorus in fertilizer, leaving the rest to flow into waterways, seeding algae blooms that can release toxins and suffocate fish. An estimated 90 percent of the pesticides used on crops dissipates into the air or leaches into groundwater.

child starving

With the global population on pace to swell to more than nine billion by 2050 amid the disruptions of climate change, scientists are racing to boost food production while minimizing collateral damage to the environment. To tackle this huge problem, they’re thinking small — very small, as in nanoparticles a fraction of the diameter of a human hair. Three of the most promising developments deploy nanoparticles that boost the ability of plants to absorb nutrients in the soil, nanocapsules that release a steady supply of pesticides and nanosensors that measure and adjust moisture levels in the soil via automated irrigation systems.

It’s all part of a rise in precision agriculture, which seeks a targeted approach to the use of fertilizer, water and other resources. Recognizing the potential impact of nanotechnology, the U.S. Department of Agriculture’s National Institute of Food and Agriculture (NIFA) beefed up funding between 2011 and 2015, from $10 million to $13.5 million. India, China and Brazil are also joining the latest green revolution. Scientists led by Pratim Biswas and Ramesh Raliya at Washington University in St. Louis have harnessed fungi to synthesize nanofertilizer. When sprayed on mung bean leaves, the zinc oxide nanoparticles increase the activity of three enzymes in the plant that convert phosphorus into a more readily absorbable form. Compared to untreated plants, nanofertilized mung beans absorbed nearly 11 percent more phosphorus and showed 27 percent more growth with a 6 percent increase in yield.

Raliya and his colleagues are also developing nanoparticles that enhance plants’ absorption of sunlight and investigating how nanofertilizers fortify crops with nutrients. In a study earlier this year, they found that zinc oxide and titanium dioxide nanoparticles increased levels of the antioxidant lycopene in tomatoes by up to 113 percent. Next, they want to design nanoparticles that enhance the protein content in peanuts. Along with mung beans, peanuts are a major source of protein in many developing countries.

Others are exploring nanoparticles that protect plants against insects, fungi and weeds. The Connecticut Agricultural Experiment Station and other institutions recently began field trials that use several types of metal oxide nanoparticles on tomato, eggplant, corn, squash and sorghum plants in areas infected with fungi known to threaten crops. Researchers led by Leonardo Fernandes Fraceto, of the Institute of Science and Technology, São Paulo State University, Campus Sorocaba, are designing slow-release nanocapsules that contain two types of fungicides or herbicides to reduce the likelihood of targeted fungi and weeds developing resistance. Scientists at the University of Tehran are conducting similar research. Still others are working on nanocapsules that release plant growth hormones. Existing technology could increase average yields up to threefold in many parts of Africa.

Inhibited On/Off Switch Protein Could Prevent Prostate Cancer

Researchers at the University of Georgia (UGA) have created a new therapeutic for prostate cancer that has shown great efficacy in mouse models of the disease. The treatment is designed to inhibit the activity of a protein called PAK-1, which contributes to the development of highly invasive prostate cancer cells. Aside from non-melanoma skin cancer, prostate cancer is the most common cancer among men in the U.S., according to the Centers for Disease Control and Prevention. It is also one of the leading causes of cancer death among men of all races.

prostateCANCERcells

PAK-1 is kind of like an on/off switch,” said study co-author Somanath Shenoy, an associate professor in UGA‘s College of Pharmacy. “When it turns on, it makes cancerous cells turn into metastatic cells that spread throughout the body.

With the help of Brian Cummings, an associate professor in UGA‘s College of Pharmacy, the researchers developed a way to package and administer a small molecule called IPA-3, which limits the activity of PAK-1 proteins.

Researchers have published their findings recently in the journal Nanomedicine: Nanotechnology, Biology and Medicine.

Source: http://news.uga.edu/

How To Inhibit Breast Cancer Metastasis

Researchers at Case Western Reserve University combined finely crafted nanoparticles with one of nature’s potent disrupters to prevent the spread of triple-negative breast cancer in mouse models. The highly aggressive cancer subtype is difficult to manage and, currently, the FDA has no approved targeted treatments. But striking results from a new study, published in the journal Cancer Research make the researchers optimistic they have a potential game-changer for triple negative cancer and more.


breast cancer

There are multiple targets within a cell,” said William Schiemann, professor of oncology at the Case Western Reserve School of Medicine and the Case Comprehensive Cancer Center, and a leader of the research. “With this technology, we can target any gene or any location, for other cancers, more diseases—potentially even immunology-based diseases.”

Regular injections of nanoparticles carrying siRNA,  silenced the gene that regulates expression of the protein β3 integrin. Expression of β3 integrin in the cell-development process called the endothelial-mesenchymal transition (EMT), is essential for the cancer to spread from its primary tumor.

Nearly 15 percent of breast cancers in the United States are triple negative, and the subtype is most prevalent among African-American women in their 20s and 30s. According to the National Cancer Institute, the five-year survival rate for women whose cancer is discovered early and contained to a primary tumor is 98 percent. But, the survival rate for those diagnosed with distant metastases plummets to less than 25 percent.

To try to tackle metastasis, Schiemann teamed with Zheng-Rong Lu, the M. Frank and Margaret Domiter Rudy Professor of Biomedical Engineering at Case Western Reserve, Jenny Parvani, now a postdoctoral investigator, PhD student Maneesh Gujrati and undergraduate student Margaret Mack. Lu’s lab has been developing lipid-based nanoparticles to deliver medicines to specific targets in the body for a decade. Lipids include fats and oils, but these organic molecules are also building blocks in cell structures and functions.

In this study, five mice with a mouse version of triple-negative breast cancer were injected with particles every five days for 14 weeks. Compared to control mice, the treated mice’s tumors shrunk significantly, but more importantly, the treatment significantly inhibited metastasisFour weeks after treatment was stopped, the treated mice remained tumor free while cancer continued to grow in untreated controls. No significant difference in body weight across treatment groups and controls were found, indicating low toxicity of the treatments.

Source: http://blog.case.edu/

How To Diagnose Heart Attacks With A Thermometer

Diagnosing a heart attack can require multiple tests using expensive equipment. But not everyone has access to such techniques, especially in remote or low-income areas. Now scientists have developed a simple, thermometer-like device that could help doctors diagnose heart attacks with minimal materials and cost. The report on their approach appears in the ACS journal Analytical Chemistry.
thermometer to diagnose heart attacks
Sangmin Jeon from Pohang University of Science and Technology (Korea), and colleagues note that one way to tell whether someone has had a heart attack involves measuring the level of a protein called troponin in the person’s blood. The protein’s concentration rises when blood is cut off from the heart, and the muscle is damaged. Today, detecting troponin requires bulky, expensive instruments and is often not practical for point-of-care use or in low-income areas. Yet three-quarters of the deaths related to cardiovascular disease occur in low- and middle-income countries. Early diagnosis could help curb these numbers, so Jeon’s team set out to make a sensitive, more accessible test.

Inspired by the simplicity of alcohol and mercury thermometers, the researchers created a similarly straightforward way to detect troponin. It involves a few easy steps, a glass vial, specialized nanoparticles, a drop of ink and a skinny tube. When human serum with troponin — even at a minute concentration — is mixed with the nanoparticles and put in the vial, the ink climbs up a protruding tube and can be read with the naked eye, just like a thermometer.

Source: http://www.acs.org/content/acs/

Trojan Horse Nanoparticles To Kill Cancer

Scientists at Brunel University London have found a way of targeting hard-to-reach cancers and degenerative diseases using nanoparticles, but without causing the damaging side effects the treatment normally brings. In a huge step forward in the use of nanomedicine, the research helped discover proteins in the blood that disguise nanoparticles so they are absorbed into cells without causing inflammation and destroying healthy cells. Carbon nanotubes (CNTs) triggered a chain reaction in the complement system, which is part of the innate immune system and is responsible for clearing pathogens and toxins. The team, led by Dr Uday Kishore of the Centre for Infection, Immunity and Disease Mechanisms, found the entire complement system was activated, from C1 at the start to C5 at the end. This in turn activated the cell-killing membrane attack complex. In principle, this should have caused an acute allergic, inflammatory reaction. However the opposite was true.

nanoparticles
Using the data from this study, carbon nanoparticles coated with genetically- engineered proteins are being used to target glioblastoma, the most aggressive form of brain tumour
By using a protein recognised by the immune system to effectively disguise carbon nanoparticles, we will be able to deploy these tiny particles to target hard-to- reach areas without damaging side effects to the patient. This is a big step forward. It is like understanding how to use penicillin safely and could be as revolutionary to modern medicine as its twentieth century predecessor”, said Dr Uday Kishore, from Brunel University London’s College of Health and Life Sciences,

Source: http://www.brunel.ac.uk/

Cannabis And The New Medecine

Revolutionary nanotechnology method could help improve the development of new medicine and reduce costs. Researchers from the Nano-Science Center and the Department of Chemistry at the University of Copenhagen – Denmark – have developed a new screening method that makes it possible to study cell membrane proteins that bind drugs, such as cannabis and adrenaline, while reducing the consumption of precious samples by a billion times. About 40% of all medicines used today work through the so-called “G protein-coupled receptors”. These receptors react to changes in the cell environment, for example, to increased amounts of chemicals like cannabis, adrenaline or the medications we take and are therefore of paramount importance to the pharmaceutical industry.

cannabis
There is a lot of attention on research into “G protein-coupled receptors“, because they have a key role in recognizing and binding different substances. Our new method is of interest to the industry because it can contribute to faster and cheaper drug development”, explains Professor Dimitrios Stamou, who heads the Nanomedicine research group at the Nano-Science Center, where the method has been developed.
The new method is described in the journal Nature Methods.
Source: http://nano.ku.dk/