Next Monday 14 July 2014 PGARD (Parliamentary Group on Asbestos Related Diseases) have organised a luncheon at Parliament House, Canberra for various party politicians to be present. Also ASEA (Asbestos Safety and Eradication Agency) are also supporting this important event to raising awareness about the dangers of asbestos. I have been invited to be a keynote/guest speaker. It is an honour to have been asked and I am looking forward to this event.I will be flying up on Sunday afternoon and staying with good friends for the night rather than an early flight on the Monday morning that could leave me feeling exhausted and a bit short of breath.Our winter weather has well and truly set in today. We were lucky to get above 4 degrees celcius. …Read more
Two new articles published in The Lancet report the first ever successful operations in humans to reconstruct the alar wings of the nose (nostrils) (Martin et al), and to implant tissue-engineered vaginal organs in women with a rare syndrome that causes the vagina to be underdeveloped or absent (Atala et al), in both cases using the patients’ own tissue.In one paper, led by Professor Ivan Martin from the University of Basel in Switzerland, scientists report having engineered a human cartilage graft from patients’ own nasal septum cartilage cells to successfully rebuild the nostrils (alar lobule) of five individuals whose noses were damaged by skin cancer. One year after reconstruction, all five recipients were satisfied with their ability to breathe, as well as the cosmetic appearance of their nose, and did not report any local or systemic adverse events.The nose is the most common site of non-melanoma skin cancer, because of its cumulative exposure to sunlight, with the highest frequency of cancer occurring on the alar lobule. Currently, when removing skin cancers, surgeons often have to cut away parts of cartilage, (for instance from the nasal septum, ear, or rib) as grafts to functionally reconstruct the tumour excision site. However, this painful and invasive procedure involves major additional surgery, and has been associated with complications at the site from which cartilage has been removed.A team from the University of Basel, Switzerland, investigated an alternative approach using engineered cartilage tissue grown from patients’ own cells. They extracted the cartilage cells (chondrocytes) from the nasal septum of each patient, and multiplied the cells by exposing them to growth factors for two weeks. The expanded cells were seeded onto collagen membranes and cultured for two additional weeks, generating cartilage 40 times larger than the original biopsy. When the engineered grafts were ready they were shaped according to the defect and implanted.According to Professor Martin, “The engineered cartilage had clinical results comparable to the gold standard cartilage graft surgery. This new technique could help the body accept the new tissue more easily, and improve the stability and functionality of the nostril. Our success is based on the long-standing, effective integration in Basel between our experimental group at the Department of Biomedicine and the surgical disciplines. It opens the way to using this engineered cartilage for more challenging reconstructions in facial surgery such as the complete nose, eyelid, or ear. …Read more
This week has flown! A visit last Tuesday to the hospital for my Picc line to be dressed and bloods taken. No chemo that week was scheduled and just as well – my bloods were still quite low from the week before. Tomorrow picc line to be dressed, bloods taken, appt with my oncologist and the green light for chemo to go ahead gemcidibine and carboplatin.We have had friends staying for 5 nights from the Gold Coast, Queensland – it was great to be normal for a few days and concentrate on other things instead of chemotherapy/treatments. I held a dinner party the first night as it was Margit’s birthday. Spinach and ricotta cannelloni followed by a pear/walnut upside down cake. I was quite exhausted the next …Read more
Sep. 9, 2013 — Researchers from the University of Pennsylvania have demonstrated a new mechanism for extracting energy from light, a finding that could improve technologies for generating electricity from solar energy and lead to more efficient optoelectronic devices used in communications.Dawn Bonnell, Penn’s vice provost for research and Trustee Professor of Materials Science and Engineering in the School of Engineering and Applied Science, led the work, along with David Conklin, a doctoral student. The study involved a collaboration among additional Penn researchers, through the Nano/Bio Interface Center, as well as a partnership with the lab of Michael J. Therien of Duke University.”We’re excited to have found a process that is much more efficient than conventional photoconduction,” Bonnell said. “Using such an approach could make solar energy harvesting and optoelectronic devices much better.”The study was published in the journal ACS Nano and was discussed at a press conference at the American Chemical Society National Meeting and Exhibition in Indianapolis today.The new work centers on plasmonic nanostructures, specifically, materials fabricated from gold particles and light-sensitive molecules of porphyin, of precise sizes and arranged in specific patterns. Plasmons, or a collective oscillation of electrons, can be excited in these systems by optical radiation and induce an electrical current that can move in a pattern determined by the size and layout of the gold particles, as well as the electrical properties of the surrounding environment.Because these materials can enhance the scattering of light, they have the potential to be used to advantage in a range of technological applications, such as increasing absorption in solar cells.In 2010, Bonnell and colleagues published a paper in ACS Nano reporting the fabrication of a plasmonic nanostructure, which induced and projected an electrical current across molecules. In some cases they designed the material, an array of gold nanoparticles, using a technique Bonnell’s group invented, known as ferroelectric nanolithography.The discovery was potentially powerful, but the scientists couldn’t prove that the improved transduction of optical radiation to an electrical current was due to the “hot electrons” produced by the excited plasmons. Other possibilities included that the porphyin molecule itself was excited or that the electric field could focus the incoming light.”We hypothesized that, when plasmons are excited to a high energy state, we should be able to harvest the electrons out of the material,” Bonnell said. “If we could do that, we could use them for molecular electronics device applications, such as circuit components or solar energy extraction.”To examine the mechanism of the plasmon-induced current, the researchers systematically varied the different components of the plasmonic nanostructure, changing the size of the gold nanoparticles, the size of the porphyin molecules and the spacing of those components. They designed specific structures that ruled out the other possibilities so that the only contribution to enhanced photocurrent could be from the hot electrons harvested from the plasmons.”In our measurements, compared to conventional photoexcitation, we saw increases of three to 10 times in the efficiency of our process,” Bonnell said. …Read more
Sep. 4, 2013 — A University of Iowa physiologist has a new technique to measure the stiffness of the aorta, a common risk factor for heart disease. And it can be as simple as measuring the pulse in your finger.The new procedure developed by Gary Pierce, assistant professor in the Department of Health and Human Physiology, works by placing an instrument called a transducer on the finger or over the brachial artery, located inside the arm just beneath the elbow. The readout, combined with a person’s age and body mass index, lets physicians know whether the aorta has stiffened.Currently, physicians see whether a patient has a hardened aorta by recording a pulse from the carotid artery, located in the neck, and the femoral artery, which is located in the groin. Taking a pulse from the finger or on the arm is easier to record and nearly as accurate, Pierce says. It also works better with obese patients, whose femoral pulse can be difficult to obtain reliably, he adds.”The technique is more effective in that it is easy to obtain just one pulse waveform in the finger or the brachial artery, and it’s less intrusive than obtaining a femoral waveform in patients,” says Pierce, first author on the paper, published in the American Journal of Physiology Heart and Circulatory Physiology. “It also can be easily obtained in the clinic during routine exams similar to blood pressure tests.”Heart disease is the leading cause of death for both men and women in the United States, killing about 600,000 people every year, according to the federal Centers for Disease Control and Prevention.One key to a healthy heart is a healthy aorta. A person’s heart has to work harder when the aorta, the large artery that leaves the heart and delivers blood to the body’s tissues, stiffens due to aging and an inactive lifestyle. The harder a person’s heart needs to work, the higher risk he or she has for developing high blood pressure, stroke and a heart attack.Since people can live for years without any knowledge of existing cardiovascular problems, this new measurement tool is especially important. It can provide useful diagnostic information for middle-aged and older patients, who are most susceptible to having hardened arteries that can lead to heart disease.Regular assessments of the aorta may help reduce those risks. …Read more
July 24, 2013 — Researchers have designed tiny, light-controlled gold particles that can release DNA controls to switch blood clotting off and on.Share This:The results are reported July 24 in the open access journal PLOS ONE by Kimberly Hamad-Schifferli and colleagues from the Massachusetts Institute of Technology.The two-way switch for blood clotting relies on the ability of two gold nanoparticles to selectively release different DNA molecules from their surface under different wavelengths of laser excitation. When stimulated by one wavelength, one nanorod releases a piece of DNA that binds the blood protein thrombin and blocks clot formation. When the complementary DNA piece is released from the other nanorod, it acts as an antidote and releases thrombin, restoring clotting activity.Natural blood clotting is precisely synchronized to occur at the right time and place. Wound healing, surgery and other conditions require manipulation of this process, typically through the use of anticoagulants like heparin or warfarin. However, these drugs are inherently one-sided as they can only block clotting, and reversing their effects depends on removing them from the bloodstream. The methods described in this research open up new possibilities for more precise, selective control of the blood clotting process during therapy.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length. For further information, please contact the source cited above. Journal Reference:Helena de Puig, Anna Cifuentes Rius, Dorma Flemister, Salmaan H. Baxamusa, Kimberly Hamad-Schifferli. …Read more
July 17, 2013 — Heart tissue sustains irreparable damage in the wake of a heart attack. Because cells in the heart cannot multiply and the cardiac muscle contains few stem cells, the tissue is unable to repair itself — it becomes fibrotic and cannot contract properly.In their search for innovative methods to restore heart function, scientists have been exploring cardiac “patches” that could be transplanted into the body to replace damaged heart tissue. Now, in his Tissue Engineering and Regenerative Medicine Laboratory, Dr. Tal Dvir and his PhD student Michal Shevach of Tel Aviv University’s Department of Molecular Microbiology and Biotechnology and the Center for Nanoscience and Nanotechnology, together with their colleagues, are literally setting a gold standard in cardiac tissue engineering.To meet one of the biggest challenges in the development of cardiac patches — ensuring that engineered tissue can mimic the heart’s coordinated electrical system, which controls heartbeat and rhythm — they integrated cardiac cells with nanofibers made of gold particles to form functional engineered tissues. Their goal is to optimize electrical signalling between cells.Gold has been found to increase the connectivity of biomaterials, explains Dr. Dvir. With the addition of the gold particles, cardiac tissues contract much faster and stronger as a whole, he reports, making them more viable for transplants. The research was recently published in the Journal of Materials Chemistry B.Lending nature a helping handOn their surface, heart cells contain proteins that are responsible for transferring electrical signals. But the process of tissue engineering itself leads to the loss of these proteins. And while the cells will start to produce them again naturally, says Dr. …Read more
July 17, 2013 — We value gold for many reasons: its beauty, its usefulness as jewelry, and its rarity. Gold is rare on Earth in part because it’s also rare in the universe. Unlike elements like carbon or iron, it cannot be created within a star. Instead, it must be born in a more cataclysmic event — like one that occurred last month known as a short gamma-ray burst (GRB). Observations of this GRB provide evidence that it resulted from the collision of two neutron stars — the dead cores of stars that previously exploded as supernovae. Moreover, a unique glow that persisted for days at the GRB location potentially signifies the creation of substantial amounts of heavy elements — including gold.”We estimate that the amount of gold produced and ejected during the merger of the two neutron stars may be as large as 10 moon masses — quite a lot of bling!” says lead author Edo Berger of the Harvard-Smithsonian Center for Astrophysics (CfA).A gamma-ray burst is a flash of high-energy light (gamma rays) from an extremely energetic explosion. Most are found in the distant universe. Berger and his colleagues studied GRB 130603B which, at a distance of 3.9 billion light-years from Earth, is one of the nearest bursts seen to date.Gamma-ray bursts come in two varieties — long and short — depending on how long the flash of gamma rays lasts. GRB 130603B, detected by NASA’s Swift satellite on June 3rd, lasted for less than two-tenths of a second.Although the gamma rays disappeared quickly, GRB 130603B also displayed a slowly fading glow dominated by infrared light. Its brightness and behavior didn’t match a typical “afterglow,” which is created when a high-speed jet of particles slams into the surrounding environment.Instead, the glow behaved like it came from exotic radioactive elements. …Read more
June 28, 2013 — The development of an easy to use, low cost method of detecting dengue virus in mosquitoes based on gold nanoparticles is reported in BioMed Central’s open access journal Virology Journal. The assay is able to detect lower levels of the virus than current tests, and is easy to transport and use in remote regions.Half the world’s population is at risk of Dengue virus infection — it infects 50-100 million people per year, approximately half a million of these require hospitalization and 2.5% (most of which are children) will die. It is one of the most dangerous viruses in the world with no vaccine, and it does not respond to antiviral therapy. The main method of controlling infection remains destruction of the standing water where the mosquitoes, which transmit the virus to people, breed.It is consequently vitally important to have a way of determining if mosquitoes are carrying Dengue virus, which can be used on site and that does not require specialist equipment.Researchers from the University of Notre Dame, USA, used a DNAzyme linked to gold nanoparticles which recognises a short sequence of the viral RNA genome common to all four types of Dengue. Once bound, adding magnesium and heating to 37C causes the DNAZyme to cut the RNA leaving the gold nanoparticles free to clump together. This aggregation can be easily seen as a red to clear/colourless colour change.The components of this test are stable at temperatures above 30C which means that they are easy to store and transport and the assay is able to detect as little as 10 viruses in each sample containing 10-20 mosquitoes.The ultimate goal is to detect virus infection in just a single infected mosquito or cell. Dr James Carter, the lead author of this study explained, “Full development of our novel DDZ-AuNP detection method will provide a practical, rapid, and low cost alternative for the detection of DENV in mosquito cells and tissues, and possibly infected patient serum, in a matter of minutes with little to no specialized training required.”Read more
June 25, 2013 — Scientists in the US have developed a novel vaccination method that uses tiny gold particles to mimic a virus and carry specific proteins to the body’s specialist immune cells.The technique differs from the traditional approach of using dead or inactive viruses as a vaccine and was demonstrated in the lab using a specific protein that sits on the surface of the respiratory syncytial virus (RSV).The results have been published today, 26 June, in IOP Publishing’s journal Nanotechnology by a team of researchers from Vanderbilt University.RSV is the leading viral cause of lower respiration tract infections, causing several hundred thousand deaths and an estimated 65 million infections a year, mainly in children and the elderly.The detrimental effects of RSV come, in part, from a specific protein, called the F protein, which coats the surface of the virus. The protein enables the virus to enter into the cytoplasm of cells and also causes cells to stick together, making the virus harder to eliminate.The body’s natural defence to RSV is therefore directed at the F protein; however, up until now, researchers have had difficulty creating a vaccine that delivers the F protein to the specialised immune cells in the body. If successful, the F protein could trigger an immune response which the body could ‘remember’ if a subject became infected with the real virus.In this study the researchers created exceptionally small gold nanorods, just 21 nanometres wide and 57 nanometres long, which were almost exactly the same shape and size as the virus itself. The gold nanorods were successfully coated with the RSV F proteins and were bonded strongly thanks to the unique physical and chemical properties of the nanorods themselves.The researchers then tested the ability of the gold nanorods to deliver the F protein to specific immune cells, known as dendritic cells, which were taken from adult blood samples.Dendritic cells function as processing cells in the immune system, taking the important information from a virus, such as the F protein, and presenting it to cells that can perform an action against them―the T cells are just one example of a cell that can take action.Once the F protein-coated nanorods were added to a sample of dendritic cells, the researchers analysed the proliferation of T cells as a proxy for an immune response. They found that the protein-coated nanorods caused the T cells to proliferate significantly more compared to non-coated nanorods and just the F protein alone.Not only did this prove that the coated-nanorods were capable of mimicking the virus and stimulating an immune response, it also showed that they were not toxic to human cells, offering significant safety advantages and increasing their potential as a real-life human vaccine.Lead author of the study, Professor James Crowe, said: “A vaccine for RSV, which is the major cause of viral pneumonia in children, is sorely needed. This study shows that we have developed methods for putting RSV F protein into exceptionally small particles and presenting it to immune cells in a format that physically mimics the virus. Furthermore, the particles themselves are not infectious.”Due to the versatility of the gold nanorods, Professor Crowe believes that their potential use is not limited to RSV.”This platform could be used to develop experimental vaccines for virtually any virus, and in fact other larger microbes such as bacteria and fungi.”The studies we performed showed that the candidate vaccines stimulated human immune cells when they were interacted in the lab. The next steps to testing would be to test whether or not the vaccines work in vivo” Professor Crowe continued.Read more
June 21, 2013 — For decades, electronic devices have been getting smaller, and smaller, and smaller. It’s now possible — even routine — to place millions of transistors on a single silicon chip.But transistors based on semiconductors can only get so small. “At the rate the current technology is progressing, in 10 or 20 years, they won’t be able to get any smaller,” said physicist Yoke Khin Yap of Michigan Technological University. “Also, semiconductors have another disadvantage: they waste a lot of energy in the form of heat.”Scientists have experimented with different materials and designs for transistors to address these issues, always using semiconductors like silicon. Back in 2007, Yap wanted to try something different that might open the door to a new age of electronics.”The idea was to make a transistor using a nanoscale insulator with nanoscale metals on top,” he said. “In principle, you could get a piece of plastic and spread a handful of metal powders on top to make the devices, if you do it right. But we were trying to create it in nanoscale, so we chose a nanoscale insulator, boron nitride nanotubes, or BNNTs for the substrate.”Yap’s team had figured out how to make virtual carpets of BNNTs,which happen to be insulators and thus highly resistant to electrical charge. Using lasers, the team then placed quantum dots (QDs) of gold as small as three nanometers across on the tops of the BNNTs, forming QDs-BNNTs. BNNTs are the perfect substrates for these quantum dots due to their small, controllable, and uniform diameters, as well as their insulating nature. BNNTs confine the size of the dots that can be deposited.In collaboration with scientists at Oak Ridge National Laboratory (ORNL), they fired up electrodes on both ends of the QDs-BNNTs at room temperature, and something interesting happened. …Read more
May 29, 2013 — The fabled ivory carvings from the ancient Phoenician city of Arslan Tash — literally meaning “Stone Lion” — may appear a dull monochrome in museums today, but they glittered with brilliant blue, red, gold and other colors 2,800 years ago, a new study has confirmed after decades of speculation. It appears in the ACS journal Analytical Chemistry.
Ina Reiche and colleagues explain that these carvings are rare, housed in museums like the Louvre, and art experts regard them as the most beautiful ivory carvings of the era. Experts long believed that the lion heads, amulets and other objects were brightly colored, rather than the bland beiges and whites that remain today. But until recently, there was no adequate way to test the ivories for traces of pigment without damaging these priceless objects.
The scientists describe how a non-destructive testing technology brought to life traces of red, blue and other pigments — and gold gilding — allowing re-creation of the long-vanished colors that decorated the original ivories. In addition to contributing to a new understanding of the Phoenician carvings, the technology could be used to glimpse the original paintings on other objects, the authors note. Those include the Elgin Marbles, the classical Greek marble sculptures that originally were part of the Parthenon and other buildings on the Acropolis in Athens.
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- Ina Reiche, Katharina Müller, Marie Albéric, Oliver Ulrich Heinz Paul Scharf, Andrea Wähning, Aniouar Bjeoumikhov, Martin Radtke, Rolf Simon. Discovering vanished paints and naturally formed gold nanoparticles on 2800 years old Phoenician ivories using SR-FF-microXRF with the Color X-ray Camera. Analytical Chemistry, 2013; : 130513030719004 DOI: 10.1021/ac4006167
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