#New methodology tracks changes in DNA methylation in real time at single-cell resolution Whitehead Institute researchers have developed a methodology to monitor changes in DNA methylation over time in individual cells.
DNA methylation is essential for the proper control of gene expression and cell identityhat enables cells with the same genetic material to become, for example, a nerve cell, a muscle cell or a skin cell.
Certain diseases, including cancer, involves changes in DNA methylation patterns, and the ability to document these alterations aid in the development of novel therapies. ethylation is really key in development,
in disease, and in cancer, says Whitehead Founding Member Rudolf Jaenisch, who is also a professor of biology at MIT. his reporter is a very important tool.
We believe it will allow us to look in a very detailed way at issues like imprinting during development
and screening for the activation of genes silenced in diseases like cancer. This method will allow us to see which drug will activate a given gene.
An individual cells rely on the same set of genes as instructions for protein production. The differences between a muscle cell and a brain cell are attributable to differences in gene expression;
that is, which genes are turned on and off. DNA methylationhe addition of methyl groups to the DNAS an epigenetic mechanism that controls gene expression.
In most cases, methylated genes are switched off, while unmethylated genes are active. To date, scientists have only been able to study methylation in a population of cells by taking a napshotof a few cells,
a process that destroys the very cells under study. Because most cell populations in vivo are heterogeneous,
and methylation can change over time, existing approaches have offered limited insight into this fundamental biological control.
Creating a system that dynamically visualizes methylation at the level of a single cell intrigued Yonatan Stelzer
a postdoctoral researcher in Jaenisch lab. Working with graduate student Chikdu Shivalila, Stelzer synthesized a DNA methylation reporter that mirrors
whether a nearby region is methylated. When the target region is unmethylated, the reporter is also unmethylated,
Stelzer and Shivalila describe their work in this week issue of the journal Cell. harmaceutical companies have been interested in manipulating methylation in disease
For example, they could look for a drug that could change the hypermethylation that has been associated with a specific cancer.
inexpensive tests using DNA Chemists at the University of Montreal used DNA molecules to developed rapid,
Their findings in the Journal of the American Chemical Society, may aid efforts to build point-of-care devices for quick medical diagnosis of various diseases ranging from cancer, allergies, autoimmune diseases, sexually transmitted diseases (STDS),
when atoms are brought too close together to detect a wide array of protein markers that are linked to various diseases.
The design was created by the research group of Alexis Vallée-Bélisle, a professor in the Department of chemistry at University of Montreal. espite the power of current diagnostic tests,
and the results sent back to the doctor office. If we can move testing to the point of care,
which would enhance the effectiveness of medical interventions. The key breakthrough underlying this new technology came by chance. hile working on the first generation of these DNA-base tests,
(or traffic) at the surface of a sensor, which drastically reduced the signal of our tests,
postdoctoral scholar at the University of Montreal and first author of the study. nstead of having to fight this basic repulsion effect,
and limits the ability of this DNA to hybridize to its complementary strand located on the surface of a gold electrode.
Francesco Ricci, a professor at University of Rome Tor Vergata who also participated in this study,
explains that this novel signaling mechanism produces sufficient change in current to be measured using inexpensive electronics similar to those in the home glucose test meter used by diabetics to check their blood sugar.
allowing us to build inexpensive devices that could detect dozens of disease markers in less than five minutes in the doctor office
and easily multiplexed biosensor could significantly improve patient health by providing new point-of-care diagnostics for a wide variety of diseases said Patricia Escoffier, Project Manager at Univalor.
including pathogen detection in food or water and therapeutic drug monitoring at home, a feature which could drastically improve the efficient of various class of drugs and treatments v
#afepay First anti-fraud system to use existing credit card readers From large-scale data breaches such as the 2013 Target case to local schemes that use skimming devices to steal data at the gas pump,
credit card fraud is becoming commonplace. Because existing magnetic card readers use plain text to store confidential information, they are vulnerable to an untrusted card reader or skimming device.
Analyst firm Alite Group estimates that this vulnerability is adding up to $8 billion in incurred losses per year in the U s. Solutions have been proposeduch as integrated circuit cards and mobile wallets systems.
However they are incompatible with current systems, making them too costly and time-consuming for retailers to implement.
For the first time, researchers have developed an inexpensive, secure method to prevent mass credit card fraud using existing magnetic card readers.
The novel techniquealled Safepayorks by transforming disposable credit card information to electrical current and driving a magnetic card chip to simulate the behavior of a physical magnetic card.
The research, led by Yinzhi Cao, assistant professor of computer science and engineering at Lehigh University, with coauthors Xiang Pan and Yan Chen from Northwestern University, will be presented at the IEEE Conference on Communications and Network security,
September 28-30, in Florence, Italy. The study will also be published as paper, afepay: Protecting against Credit card Forgery with Existing Magnetic Card Readers. ecause Safepay is backward compatible with existing magnetic card readers,
it will greatly relieve the burden of merchants in replacing card readers, said Cao. t the same time,
it will protect cardholders from mass data breaches. Broadly speaking, Safepay is related to Cyber-Physical Systems (CPS),
which are systems consisting of computational elements that control physical entities. The computational elements in Safepay consist of a mobile device and a server
which distributes disposable credit card numbers. The physical entity is the magnetic credit card chip controlled by a mobile application inside a customer mobile device.
The paper outlines the overall architecture and server-side deployment model the design of Safepay, prototype implementation and security analysis. Here how it works:
First, the user downloads and executes the mobile banking application which communicates with the bank server.
During transactions, the mobile application acquires disposable credit card numbers from the bank server, generates a wave file,
plays the file to generate electrical current, and then drives the magnetic card chip via an audio jack or Bluetooth.
The critical elements that make Safepay unique are: Disposable credit card information that expires after a limited time or number of usages (i e.,
, just one time) so, even if the information is leaked, it cannot be used for future transactions. A magnetic credit card chip that makes it completely compatible with existing readers.
In the evaluation, the researchers show that the cost of the magnetic card chip is about fifty cents,
and could be even lower if manufactured in large scale. A mobile banking application that automates the process making it extremely user friendly.
Cao and his colleagues conducted real-world experiments with the Safepay technology performing transactions with a vending machine
a gas station and a university coffee shop. During the experiments, they used a bank application, cell phone application and magnetic credit card chip.
The disposable credit card information was acquired from Shopsafe by registering several disposable credit card numbers with Bank of america.
In all three scenarios, the Safepay method worked and the transactions were successful
#Researchers Discover A New Mechanism of Proteins to Block HIV There is little doubt that the Human immunodeficiency virus,
or HIV, is devastating. More than 1. 2 million people in the United states are living with HIV
and more than 47,000 people are diagnosed annually. Now, University of Missouri researchers have made a discovery in how specialized proteins can inhibit the virus,
opening the door for progress in the fight against HIV and for the production of advanced therapeutics to combat the disease.
Human cells express Interferon Induced Transmembranes (IFITM) proteins that possess antiviral characteristics. These proteins have been shown to inhibit a number of viruses including influenza A
West Nile, Dengue fever and Ebola. In his study, Shan-Lu Liu, an associate professor in the Department of Molecular Microbiology and Immunology in the School of medicine and an investigator in the Bond Life sciences Center at MU, targeted IFITM proteins
and their antiviral function. e have understood long that IFITM proteins have antiviral functions, but until now we did not know exactly how the proteins specifically inhibited the transmission of HIVLIU said. ee known that HIV-1,
the most common HIV strain, can be transmitted from cell to cell or through a cell-free transmission in
Our research discovered that IFITM proteins can help inhibit the viral cell-to-cell infection
Jingyou Yu, a doctoral student in MU pathobiology graduate program, conducted experiments to show that IFITM proteins, particularly IFITM2 and IFITM3, block HIV cell-to-cell transmission.
who is also a graduate student in pathobiology, and discovered that IFITM proteins specifically interact with the HIV-1 envelope glycoprotein
given our previous finding in PLOS Pathogens where we found that this family of proteins generally affects the lipid property of cell membrane
scientists are constantly learning more about virus transmission and host response to viral infections. By understanding and visualizing how some IFITM proteins can inhibit
we are getting closer to finding better therapeutic approaches in the fight against HIV. The study, FITM Proteins Restrict HIV-1 Infection by Antagonizing the Envelope Glycoprotein,
recently was published in Cell Reports. The work was supported in part by NIH grants (AI112381 AI109464, AI105584 and AI107095.
The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies.
Eric O. Freed, director and a senior investigator of the HIV Dynamics and Replication Program within the National Cancer Institute, Chen Liang, an associate professor at Mcgill University and Benjamin Chen
, an associate professor of infectious diseases at the Icahn School of medicine at Mount sinai, New york contributed to the study o
#New system for human genome editing has potential to increase power and precision of DNA engineering A team including the scientist who first harnessed the CRISPR-Cas9 system for mammalian genome editing has identified now a different CRISPR system with the potential for even simpler and more precise genome engineering.
In a study published in Cell, Feng Zhang and his colleagues at the Broad Institute of MIT and Harvard and the Mcgovern Institute for Brain Research at MIT,
with co-authors Eugene Koonin at the National institutes of health, Aviv Regev of the Broad Institute and the MIT Department of biology,
and John van der Oost at Wageningen University, describe the unexpected biological features of this new system
and demonstrate that it can be engineered to edit the genomes of human cells. his has dramatic potential to advance genetic engineering,
but also shows that Cpf1 can be harnessed for human genome editing and has remarkable and powerful features.
The Cpf1 system represents a new generation of genome editing technology. CRISPR sequences were described first in 1987
and their natural biological function was described initially in 2010 and 2011. The application of the CRISPR-Cas9 system for mammalian genome editing was reported first in 2013, by Zhang and separately by George Church at Harvard university.
In the new study, Zhang and his collaborators searched through hundreds of CRISPR systems in different types of bacteria,
says Zhang, the W. M. Keck Assistant professor in Biomedical engineering in MIT Department of Brain and Cognitive sciences.
The newly described Cpf1 system differs in several important ways from the previously described Cas9, with significant implications for research and therapeutics,
leaving lunt endsthat often undergo mutations as they are rejoined. With the Cpf1 complex the cuts in the two strands are offset, leaving short overhangs on the exposed ends.
Cpf1 cuts far away from the recognition site, meaning that even if the targeted gene becomes mutated at the cut site,
it can likely still be recut, allowing multiple opportunities for correct editing to occur. Fourth:
The Cpf1 system provides new flexibility in choosing target sites. Like Cas9, the Cpf1 complex must first attach to a short sequence known as a PAM,
This could be an advantage in targeting some genomes, such as in the malaria parasite as well as in humans. he unexpected properties of Cpf1 and more precise editing open the door to all sorts of applications,
including in cancer research, says Levi Garraway, an institute member of the Broad Institute, and the inaugural director of the Joint Center for Cancer Precision Medicine at the Dana-Farber Cancer Institute, Brigham and Women Hospital,
and the Broad Institute. Garraway was involved not in the research. An open approach to empower research Zhang,
As with earlier Cas9 tools, these groups will make this technology freely available for academic research via the Zhang lab page on the plasmid-sharing website Addgene, through
These groups plan to offer licenses that best support rapid and safe development for appropriate and important therapeutic uses. e are committed to making the CRISPR-Cpf1 technology widely accessible,
Zhang says. ur goal is to develop tools that can accelerate research and eventually lead to new therapeutic applications.
with other enzymes that may be repurposed for further genome editing advances. e
#Molecular diagnostics at home: Chemists design rapid, simple, inexpensive tests using DNA Chemists at the University of Montreal used DNA molecules to developed rapid,
inexpensive medical diagnostic tests that take only a few minutes to perform. Their findings may aid efforts to build point-of-care devices for quick medical diagnosis of various diseases ranging from cancer, allergies, autoimmune diseases, sexually transmitted diseases (STDS),
and many others. The new technology may also drastically impact global health, due to its potential low cost and easiness of use, according to the research team.
when atoms are brought too close together to detect a wide array of protein markers that are linked to various diseases.
The design was created by the research group of Alexis Vallée-Bélisle, a professor in the Department of chemistry at University of Montreal. espite the power of current diagnostic tests,
and the results sent back to the doctor office. If we can move testing to the point of care,
which would enhance the effectiveness of medical interventions. The key breakthrough underlying this new technology came by chance. hile working on the first generation of these DNA-base tests,
(or traffic) at the surface of a sensor, which drastically reduced the signal of our tests,
postdoctoral scholar at the University of Montreal and first author of the study. nstead of having to fight this basic repulsion effect,
and limits the ability of this DNA to hybridize to its complementary strand located on the surface of a gold electrode.
Francesco Ricci, a professor at University of Rome Tor Vergata who also participated in this study,
explains that this novel signaling mechanism produces sufficient change in current to be measured using inexpensive electronics similar to those in the home glucose test meter used by diabetics to check their blood sugar.
allowing us to build inexpensive devices that could detect dozens of disease markers in less than five minutes in the doctor office
and easily multiplexed biosensor could significantly improve patient health by providing new point-of-care diagnostics for a wide variety of diseases said Patricia Escoffier, Project Manager at Univalor.
including pathogen detection in food or water and therapeutic drug monitoring at home, a feature which could drastically improve the efficient of various class of drugs and treatments v
#Self-assembling material that grows and changes shape could lead to artificial arteries Researchers at Queen Mary University of London (QMUL) have developed a way of assembling organic molecules into complex tubular tissue-like structures without the use of moulds
or techniques like 3d printing. The study, which will appear on Monday 28 september in the journal Nature Chemistry,
and proteins can be used to create materials that exhibit dynamic behaviors found in biological tissues like growth, morphogenesis, and healing.
which would allow scientists to study diseases such as Alzheimer with a high level of similarity to the real tissue,
The technique could also contribute to the creation of better implants, complex tissues, or more effective drug screening methods.
Alvaro Mata, Director of the Institute of Bioengineering at QMUL and lead author of the paper
and Other Acute Infections A group of scientists, led by colleagues from the University of California,
and many other known pathogens present in a blood sample from an infected individual. The portable metagenomic test developed by Charles Chiu
and his team can detect the Ebola virus and many other known pathogens in less than an hour.
Detailed in a paper published in Genome Medicine on September 28th this technology could prove highly useful in settings where lab equipment
and medical infrastructure is in short supply. While most other commercially available diagnostic tests target specific pathogens, the method used in the study,
called etagenomics does not require any guesswork, and is capable of analysing all the DNA present in a sample.
and visualization software and used it on a laptop computer to leverage an emerging DNA-sequencing technology known as nanopore sequencing. his point-of-care genomic technology will be particularly attractive in the developing world,
where critical resources, including reliable electric power, laboratory space, and computational server capacity, are limited often severely,
said Chiu. Nanopore technology, currently under development by many private enterprises, distinguishes individual nucleic acids by the distinctive perturbations they create in electric currents as they pass through microscopic pores.
The USB-powered sequencer used by Chiu research team, dubbed Minion, was made by Oxford Nanopore technologies
and is no larger than a modern cell phone. Although the technology is still new and thereby prone to error,
Chiu claims it becoming faster and more accurate by the month. With the sequencing part cut down to mere minutes
the team has now set its sights on streamlining the sample preparation technique, which still requires several hours,
regardless of the setup. o our knowledge, this is the first time that nanopore sequencing has been used for real-time metagenomic detection of pathogens in complex clinical samples in the setting of human infections,
claims Chiu. nbiased point-of-care testing for pathogens by rapid metagenomic sequencing has the potential to radically transform infectious disease diagnosis in both clinical and public health settings.
Proving the robustness of their invention, the researchers successfully used their sequencing kit to detect Hepatitis C in the blood of an infected UCSF patient,
and the Chikungunya virus in a man who was asymptomatic at the time, but eventually reported having a fever and joint pains a
#First Optical Rectenna Combined Rectifier and Antenna Converts Light to DC Current Using nanometer scale components,
researchers have demonstrated the first optical rectenna, a device that combines the functions of an antenna and a rectifier diode to convert light directly into DC current.
Based on multiwall carbon nanotubes and tiny rectifiers fabricated onto them, the optical rectennas could provide a new technology for photodetectors that would operate without the need for cooling,
energy harvesters that would convert waste heat to electricity and ultimately for a new way to efficiently capture solar energy.
In the new devices developed by engineers at the Georgia Institute of technology, the carbon nanotubes act as antennas to capture light from the sun or other sources.
As the waves of light hit the nanotube antennas, they create an oscillating charge that moves through rectifier devices attached to them.
The rectifiers switch on and off at record high petahertz speeds, creating a small direct current. Billions of rectennas in an array can produce significant current,
though the efficiency of the devices demonstrated so far remains below one percent. The researchers hope to boost that output through optimization techniques,
and believe that a rectenna with commercial potential may be available within a year. e could ultimately make solar cells that are twice as efficient at a cost that is ten times lower,
and that is to me an opportunity to change the world in a very big waysaid Baratunde Cola, an associate professor in the George W. Woodruff School of Mechanical engineering at Georgia Tech. s a robust, high-temperature detector,
we could apply it to energy conversion technologies and solar energy capture. The research, supported by the Defense Advanced Research Projects Agency (DARPA), the Space and Naval Warfare (SPAWAR) Systems Center and the Army Research Office (ARO
was reported September 28 in the journal Nature Nanotechnology. Developed in the 1960s and 1970s, rectennas have operated at wavelengths as short as ten microns,
but for more than 40 years researchers have been attempting to make devices at optical wavelengths. There were many challenges:
making the antennas small enough to couple optical wavelengths, and fabricating a matching rectifier diode small enough and able to operate fast enough to capture the electromagnetic wave oscillations.
But the potential of high efficiency and low cost kept scientists working on the technology. he physics and the scientific concepts have been said out there
and make a device work, thanks to advances in fabrication technology. Using metallic multiwall carbon nanotubes and nanoscale fabrication techniques, Cola and collaborators Asha Sharma,
Virendra Singh and Thomas Bougher constructed devices that utilize the wave nature of light rather than its particle nature.
Fabricating the rectennas begins with growing forests of vertically-aligned carbon nanotubes on a conductive substrate.
the nanotubes are coated with an aluminum oxide material to insulate them. Finally, physical vapor deposition is used to deposit optically-transparent thin layers of calcium then aluminum metals atop the nanotube forest.
The difference of work functions between the nanotubes and the calcium provides a potential of about two electron volts
enough to drive electrons out of the carbon nanotube antennas when they are excited by light. In operation, oscillating waves of light pass through the transparent calcium-aluminum electrode
and interact with the nanotubes. The metal-insulator-metal junctions at the nanotube tips serve as rectifiers switching on and off at femtosecond intervals,
allowing electrons generated by the antenna to flow one way into the top electrode. Ultra-low capacitance, on the order of a few attofarads, enables the 10-nanometer diameter diode to operate at these exceptional frequencies. rectenna is basically an antenna coupled to a diode
but when you move into the optical spectrum, that usually means a nanoscale antenna coupled to a metal-insulator-metal diode,
Cola explained. he closer you can get the antenna to the diode, the more efficient it is.
So the ideal structure uses the antenna as one of the metals in the diode
which is the structure we made. The rectennas fabricated by Cola group are grown on rigid substrates,
but the goal is to grow them on a foil or other material that would produce flexible solar cells or photodetectors.
Cola sees the rectennas built so far as simple proof of principle. He has ideas for how to improve the efficiency by changing the materials
opening the carbon nanotubes to allow multiple conduction channels, and reducing resistance in the structures. e think we can reduce the resistance by several orders of magnitude just by improving the fabrication of our device structures,
he said. ased on what others have done and what the theory is showing us, I believe that these devices could get to greater than 40 percent efficiency
#Link found between blood pressure and diabetes in major new study High blood pressure sufferers have an almost 60%greater chance of developing diabetes, according to a major global study.
Study author Professor Kazem Rahimi, Deputy Director of the George Institute for Global Health UK, said that in face of earlier conflicting and inconclusive reports,
this study now reliably shows the connection between high blood pressure and diabetes and it could lead to new insights
and strategies for treating and reducing the chances of developing diabetes. his is potentially a game changer in the understanding and treatment of diabetes,
Prof Rahimi said. iabetes affects more than 400 million people worldwide, including one million in Australia, and we know that diabetics are more likely to suffer from cardiovascular disease such as heart attacks,
stroke and heart failure. igh blood pressure affects even more people at least 4. 6 million Australians. onfirming this connection reliably provides new hope for those people
and new avenues for research. e can say for certain that one causes the other, but this study helps to connect the dots,
showing that if you have high blood pressure there is a significantly greater chance of developing diabetes. nderstanding the link will help us better communicate risks to patients
and can provide another motivation for patients and doctors to aim for tight blood pressure control.
Professor Rahimi said that the link between hypertension and fatal heart issues had been documented well, but the connection to diabetes had been less clear. revious smaller studies have varied significantly
or even found no link, but now we have something clear to go on, he said.
The study, which has been published in the Journal of the American College of Cardiology (JACC), looked at the health records of 4. 1 million adults in the UK who were initially free of diabetes and cardiovascular disease and found:
For every 20 mm mercury increase on the measurement gauge, in systolic blood pressure there was a 58%higher risk of developing diabetes.
For every 10 mm mercury increase in systolic blood pressure there was a 52%higher risk of developing diabetes Higher blood pressure was associated also with a higher risk of new onset diabetes in a wide
variety of groups of individuals, including men and women, people of young (30-50), middle (51-70) and old age (71-90) as well as normal weight,
overweight and obese individuals The relative association between blood pressure and diabetes decreased as body mass index (BMI)
and age increased but absolute effects were higher in the elderly and overweight. Professor Rahimi said the research also pooled together 30 prior studies that examined risk factors for diabetes. here were similar results in this section of the research with a 77%higher chance of getting diabetes for every 20 mm
increase of mercury in systolic blood pressure, he said. sing the two complementary approaches has given us even greater confidence in the results.
Professor Rahimi said researchers could now examine the causal relationship between blood pressure and diabetes. t a minimum we know for certain that the link exists,
but is high blood pressure a cause of diabetes or just a risk factor? We still don know,
he said. n particular researchers can now look at whether lowering blood pressure is an effective treatment
or reduces the risk of getting diabetes. hese are exciting results and I look forward to seeing further developments because of this research. t
Overtext Web Module V3.0 Alpha
Copyright Semantic-Knowledge, 1994-2011