Army of Nanorobots Successfully Strangles Cancerous Tumors


Nearly 1.7 million new cases of cancer are detected in the United States each year, and each year cancer claims almost 600,000 lives in the U.S. alone, making it the second-leading cause of death nationally. Treatment is sometimes worse than the illness, as invasive surgeries can be traumatic, and chemotherapy can cause off-target effects that wreak havoc on the entire body. But a new technique described in Nature Biotechnology, which uses nanorobots — literally microscopic robots — to specifically target tumors and cut off their blood supply has the potential to change treatment forever.

In the paper, published in February, an international team of scientists demonstrated the effectiveness of using DNA nanorobots to attack tumors in mice and pigs with cancer. These nanometer-sized robots are made of DNA that unfolds itself at precisely the right time and place to deliver a drug to only the exact target in the body. The DNA, folded up like an origami package, held molecules of thrombin, an enzyme that makes blood clot.

DNA origami nanorobot
When this DNA origami nanorobot detects blood vessels associated with tumors, it opens up to deliver thrombin, a clotting factor that chokes off the blood supply to the tumor.

To test whether this novel drug delivery system works, the team of scientists from Arizona State University and the National Center for Nanoscience and Technology of the Chinese Academy of Sciences injected the nanorobots into the bloodstreams of mice with tumors. They found that the treatment effectively targeted tumors, stopping their growth and even initiating tumor death.

Stopping tumor growth isn’t enough to prove the drug works, though, as it must also prove itself safe. So, the researchers also injected the nanorobots into the bloodstreams of Bama miniature pigs, which have been shown to be good models for testing preliminary drug safety for humans. One major concern with nanorobots is that they could get into the brain and cause strokes, but this did not happen with the test subject animals.

The nanorobots open up to deliver thrombin to the blood vessels that feed the tumor.
When they detect proteins associated with cancer cells, the nanorobots open up to deliver thrombin to the blood vessels that feed the tumor.

The precision of the nanorobots, which is what makes their potential for safe cancer treatment so great, is due to their meticulously crafted structure. The drug-holding “package” is made up of DNA sheets, measuring 60 by 90 nanometers, that wrap around thrombin molecules. On the outside of the folded sheets are molecules that zero in on nucleolin, a protein that’s present in the lining of blood vessels associated with growing tumors.

These molecules, called aptamers, both target the proper spot to deliver drugs and actually open up the DNA sheet up to expose the thrombin when the nanorobot finds the right spot. In theory, when the thrombin is released, it clots the blood entering the tumor, thereby starving it of the oxygen it needs to grow. This method, which essentially strangles the tumor, is reminiscent of the class of cancer drugs known as angiogenesis inhibitors, which help inhibit the growth of blood vessels that feed tumors.

These nanorobots show great promise, but they aren’t ready for humans yet. To get there, the researchers are seeking out clinical partners to further develop this treatment pathway. Still, the fact that it seems to work in mice and pigs makes it likely that nanorobots like these will be available as cancer treatments within our lifetimes.

Abstract: Nanoscale robots have potential as intelligent drug delivery systems that respond to molecular triggers. Using DNA origami we constructed an autonomous DNA robot programmed to transport payloads and present them specifically in tumors. Our nanorobot is functionalized on the outside with a DNA aptamer that binds nucleolin, a protein specifically expressed on tumor-associated endothelial cells, and the blood coagulation protease thrombin within its inner cavity. The nucleolin-targeting aptamer serves both as a targeting domain and as a molecular trigger for the mechanical opening of the DNA nanorobot. The thrombin inside is thus exposed and activates coagulation at the tumor site. Using tumor-bearing mouse models, we demonstrate that intravenously injected DNA nanorobots deliver thrombin specifically to tumor-associated blood vessels and induce intravascular thrombosis, resulting in tumor necrosis and inhibition of tumor growth. The nanorobot proved safe and immunologically inert in mice and Bama miniature pigs. Our data show that DNA nanorobots represent a promising strategy for precise drug delivery in cancer therapy.

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Device Mimicking Female Reproductive Cycle Could Aid Research


EVATAR is a book-size lab system that can replicate a woman’s reproductive cycle. Each compartment contains living tissue from a different part of the reproductive tract. The blue fluid pumps through each compartment, chemically connecting the various tissues.

Courtesy of Northwestern University

Scientists say they’ve made a device in the lab that can mimic the human female reproductive cycle.

The researchers hope the device, assembled from living tissue, will lead to new treatments for many medical problems that plague some women, ranging from fibroids and endometriosis to infertility, miscarriages and gynecologic cancers.

The researchers described the device Tuesday in the journal Nature Communications and dubbed it the EVATAR. The name, they say, is a play on the word “avatar.”

“An avatar is kind of a digital representation of an individual in a virtual environment,” says Teresa Woodruff, a biomedical engineer in the department of obstetrics and gynecology at Northwestern University who helped create the system. “So when we thought about this synthetic version of the female reproductive tract we thought of the word EVATAR.”

To create the EVATAR, the researchers used tissues from human fallopian tubes, a uterus and cervix donated by women who had undergone surgery.

The researchers placed each tissue type in separate plastic chambers that were connected through passageways that allow fluid to circulate among them.

One chamber contained ovarian tissue from mice because human ovarian tissue is difficult to obtain.

The device is about the size of a paperback book. It also includes human liver tissue to filter toxins from the system.

The researchers were able to trigger the system to produce the cascade of hormones that usually occur during a woman’s 28-day reproductive cycle. The cycle culminated in the ovarian tissue releasing an egg.

“We were able to recapitulate the full menstrual cycle — a complete menstrual cycle,” Woodruff says.

The scientists hope to use the system to learn more about the basic biology of how the female reproductive tract functions.

“EVATAR allows us to think about all the organs kind of connected in a way that eventually we hope will be the future of personalized medicine,” Woodruff says.

Lansing Taylor, director of the University of Pittsburgh’s Drug Discovery Institute, who was not involved in developing the system, says it could be especially useful in research because of the complexity of the female reproductive system.

“It’s a very important paper,” Taylor says. “Human reproductive tissues and organs have been particularly difficult to investigate.”

The scientists stress that they only want to use the EVATAR to study anatomy and try to develop new treatments.

But at least one bioethicist wonders if others may someday try to combine this kind of technology in worrisome ways with other advances in reproductive medicine.

“Certainly the technologies are rapidly moving forward where one could imagine these technologies being used to create a baby outside the womb in the laboratory,” says Insoo Hyun, a bioethicist at Case Western Reserve University.

That would raise many ethical issues.

“If, hypothetically, you can fertilize an egg outside a body and carry it all the way to term outside the body, then who’s responsible for this baby now?” Hyun says. He also stresses that scientists are nowhere near being able to do that yet.

In the meantime, the Northwestern researchers have already started to work on a male equivalent of the EVATAR.

They’ve created a system involving male testes and prostate tissue they call the “Dude Cube.” They are working on a more complex system that would connect the Dude Tube to other parts of the anatomy — a system they dub the “ADATAR.”

Source:http://www.npr.org/

Robotics Expert Predicts Kids Born Today Will Never Drive a Car


Technology is moving very quickly these days so fast that predictions of what the future will look like are constantly changing. One day someone is predicting that the majority of cars in the U.S. will be electric, but still human-driven, and the next someone else is telling us most cars will be autonomous and will not be even be owned by those riding in them. The latest prediction posits that babies born today will never drive a car. Ever.

The prediction comes from Henrik Christensen, head of UC San Diegos Contextual Robotics Institute, who spoke with The San Diego Union-Tribune ahead of a big robotics forum being held at the university this coming February.

BMW-Teen-Drivers-Ed-Tony-and-Alexa-ready-to-go

My own prediction is that kids born today will never get to drive a car, said Christensen. Autonomous, driverless cars are 10, 15 years out. All theautomotive companies-Daimler, GM, Ford- are saying that within five years they will have autonomous, driverless cars on the road.

When asked how he feels about future generations not knowing what it is like to drive, Christensen said, I love to drive my car, but it is a question of how much time people waste sitting in traffic and not doing something else. The average person in San Diego probably spends an hour commuting every day. If they could become more productive, that would be good. With autonomous, driverless cars, we can put twice as many vehicles on the road as we have today, and do it without improving the infrastructure.

Just as others, such as Tesla CEO Elon Musk and Lyft co-founder John Zimmer, have predicted, Christensen believes car ownership as we know it will not exist in 20 years. The days of getting in your car, which sat overnight, to drive to work where it will sit for another eight or more hours until you need it again are numbered.

There would be no need to have parking garages in downtown San Diego, said Christensen.In theory, you would get out of the car and say, ‘Pick me up at 4 p.m.’ Long-term- we are talking 20 years into the future – you are not even going to own a car. A car becomes a service.

 The idea of not owning, let alone never driving, a car is a completely foreign concept to those of us that have driven our whole lives, but could Christensen be right? Will future generations never know the joys of driving a car? We are going to keep a human-operated car in the garage for Junior just in case, but what are your thoughts on this latest prediction?

Smartphone experiment tracks whether our life story is written in our gut bacteria.


Life events such as visiting another country or contracting a disease cause a significant shift in the make-up of the gut microbiota – the community of bacteria living in the digestive system, according to research published in the open access journal Genome Biology.

Two participants used smartphone apps to collect information every day for a year in the study by scientists from MIT and Harvard. The authors think the method could be rolled out to studies of human-bacteria relationships with many more participants.

https://i0.wp.com/phys.org/newman/gfx/news/2014/smartphoneex.jpg

Our microbiota is the community of bacteria that share space with our bodies, and is individual to each person. The bacteria live in harmony with us, but it is thought that the composition of our microbiota has a close relationship to our health.

After a screening process, scientists asked two volunteers to use a to log their daily activity, including their diet, exercise, bowel movements and mood and submit regular stool and saliva samples. The participants were screened before the experiment for their willingness to track such a broad range of daily actions. The two participants then logged their activity for a year, and the data from the diaries and genetic analysis of the bacteria in the samples were analysed in detail, to see what had the greatest effect on the composition of the microbiota.

The results showed that the participants had a ‘default’ microbiota, which were unaffected by sleep levels, exercise and mood. What did have a significant effect on the microbiota were two life events – one subject moved abroad, while the other had a significant bout of food poisoning which caused most pre-existing gut bacterial species to decline. The effects of relationships between diet and specific groups of manifested in a single day.

Professor Lawrence David from Duke University said: “I was surprised by our results in several ways. First, I wasn’t sure we would find correlations between fiber intake and gut bacterial dynamics on such short time scales. And I was amazed to see how profoundly a single food poisoning event impacted the . This has given us a lot of new ideas for follow up studies and analyses of gut microbial ecology, as well as enteric infectious diseases in humans.”

Indigenous malaria vaccine shows promise in mice studies.


The vaccine candidate appeared to prime the immune system of the mice against the disease

Indian scientists experimenting with a novel vaccine candidate against malaria say they have found “promising results” in mice, with “80 to 85 per cent efficacy” observed in a dozen animals they recently vaccinated.

In this 2005 photo made available by the University of Notre Dame via the CDC, an Anopheles funestus mosquito takes a blood meal from a human host.

The new vaccine candidate, created by a team at the Indian Institute of Science (IISc), contains live malaria sporozoites (an immature stage of the parasitePlasmodium berghei) with an important genetic modification. The researchers knocked out a gene that produces “heme,” a molecule central to the pathogen’s survival. The vaccine targets the pathogen as it enters the liver, the first destination in the host.

Modus operandi

INSA Senior Scientist, Department of Biochemistry, IISc, G. Padmanabhan, who leads the research at P.N. Rangarajan’s laboratory in the Department of Biochemistry, said that the vaccine candidate appeared to prime the immune system of the mice against the disease, most likely by kickstarting a T cell immune response.

These results are, however, yet to be published, he said.

“We need to repeat the experiment in a few more animals to confirm our results first,” said Viswanathan Arun Nagaraj, a Ramanujan Fellow IISc, and part of the team working on the vaccine. They will next conduct safety trials on their animal models, he added.

The premise of the vaccine — containing mutant, inactivated sporozoites (or genetically attenuated sporozoites) — draws from two critical discoveries made earlier by the same team. The first discovery, made 20 years ago, was that the parasite can produce its own “heme” to sustain itself (although it also draws the molecule from the host’s haemoglobin when the parasite finally colonises in the host’s blood stream).

Second breakthrough

In 2013, the team made its second breakthrough when it identified all the heme-producing genes and found that the parasite’s ability to manufacture heme on its own was essential in its earliest “human stage” — when it enters the host’s liver.

“Inactivating the sporozoites is always the main challenge while researching a malaria vaccine,” Prof. Padmanabhan said. By knocking out one of the heme-producing genes — ALA synthase gene — the researchers essentially created a parasite that was no longer capable of surviving in the liver, let alone being released in exponential numbers into the host’s bloodstream where it manifests as malaria.

“The heme-biosynthetic pathway could be a target for antimalarial therapies in the mosquito and liver stages of infection. The knockout parasite could also be tested for its potential as a genetically attenuated sporozoite vaccine,” Dr. Nagaraj and coauthors had anticipated in a paper published inPLoS Pathogens journal last year.

A vaccine against malaria has been a longstanding research problem especially because drugs have proved inadequate against the parasite that often develops resistance, Dr. Nagaraj said. “Only recently did we have reports from Cambodia of the parasite developing resistance to artemisinin, the most important anti-malaria drug. The parasites are developing resistance to even combination drugs.”

Among the vaccine candidates under various stages of trial around the world is the RTS,S vaccine based on a protein from the malaria sporozoite, which has shown a 30 to 50 per cent efficacy in human trials. Another vaccine being tested uses attenuated irradiated (weakened) sporozoites.

According to the WHO, malaria infected 207 million people across the world in 2012 and killed 627,000 people; nearly 80 per cent of the deaths were of children under five years of age.

 

SSC Responds to ProCESS Trial.


The Surviving Sepsis Campaign (SSC) has received many inquiries regarding the recent publication of the Protocol-Based Care for Early Septic Shock (ProCESS) trial’s effect on the continuing activities of the Campaign. (1)

 

      (1) The ProCESS trial reflects the consensus that early diagnosis of septic shock is essential. Notably, all groups in the study received on average more than 2 liters of fluid prior to randomization and more than 75% received antibiotics prior to randomization–both elements of the 3-hour Surviving Sepsis Campaign bundle. (2) The editorial accompanying the ProCESS study highlights these points. (3)
      (2) The 18% mortality rate in the “usual care” arm of ProCESS illustrates a dramatic change in the management and outcomes of patients with septic shock. (1) In comparison, septic shock mortality was 46.5% in the 2001 early goal-directed therapy trial by Rivers. (4) Given that 70% of the hospitals in ProCESS had some form of “sepsis protocol,” we believe this mortality rate demonstrates the success of the SSC in increasing awareness and attention to the challenge of early identification and management of these vulnerable patients.
      (3) Given the remarkably low mortality rate in the control arm of ProCESS, the existence of sepsis protocols in the majority of participating study institutions, and the pending results of 2 large ongoing trials (the Australian Resuscitation In Sepsis Evaluation Randomised Controlled Trial [ARISE] and The Protocolised Management in Sepsis Trial [ProMISe]), the SSC has no plans to revise the bundles or National Quality Forum (NQF)-endorsed measures at this time.
      (4) ProCESS does not address the protocolized management of patients with severe sepsis without septic shock, a group of patients for whom early detection and treatment remain critical. The aggressive protocolized management of these patients who do not yet have shock has likely lowered severe sepsis and septic shock mortality since the inception of the SSC. The recently formed Society of Critical Care Medicine/Society of Hospital Medicine (SCCM/SHM) Early Diagnosis and Treatment of Severe Sepsis on the Hospital Floors Collaboratives will focus in large part on this population. Further, the ProCESS results have no impact on the 3-hour bundle, which is the primary focus for the Collaboratives.
      (5) Regarding the SSC 6-hour bundle (2):

 

      a. A companion paper appears to support a mean arterial pressure (MAP) target of 65 mm Hg, which is one of the indicators in this bundle. (5)

 

      b. The ProCESS paper does not address repeating lactate measures in patients with elevated lactate while literature supports doing so. (6,7)

 

      c. The majority of the patients in the usual care (56.5%) and protocol-based standard care arms (57.9%) of ProCESS had central lines inserted as part of clinical care. (1) The 6-hour bundle asks only that central venous pressure (CVP) be measured and that a venous blood gas be sent from that line to obtain the central venous oxygen saturation (ScvO

2

    ). The ProCESS manuscript does not state how the CVP line was used in the usual care arm nor in the protocol-based standard therapy arm. Similarly, the NQF-endorsed measures of SSC do not set targets for these variables so credit is given for simple collection of the results. (8)

The Surviving Sepsis Campaign looks forward to additional evidence regarding the optimal resuscitation of patients with severe sepsis and septic shock. Given the existing evidence supporting early targeted resuscitation in these patients, SSC continues to recommend all elements of the current bundles.

References:

      1. Yealy DM, Kellum JA, Juang DT, et al: A randomized trial of protocol-based care for early septic shock. N Engl J Med 2014; DOI: 10.1056/NEJMoa1401602

 

      2. Dellinger RP, Levy MM, Rhodes A, et al: Surviving Sepsis Campaign: International guidelines for management of severe sepsis and septic shock: 2012. Crit Care Med 2013; 41:580–637

 

      3. Lilly CM. The ProCESS Trial –a new era of sepsis management. N Engl J Med 2014; DOI: 10.1056/NEJMe1402564

 

      4. Rivers E, Nguyen B, Havstad S, et al. Early goal-directed therapy in the treatment of severe sepsis and septic shock. N Engl J Med 2001; 345:1368-1377

 

      5. Asfar P, Meziani F, Hamel JF, et al. High versus low blood-pressure target in patients with septic shock. N Engl J Med 2014; DOI: 10.1056/NEJMoa1312173

 

      6. Jones AE, Shapiro NI, Trzeciak S, et al. Lactate clearance vs central venous oxygen saturation as goals of early sepsis therapy: a randomized clinical trial. JAMA 2010: 303:739-746

 

      7. Jansen TC, van Bommel J, Schoonderbeek FJ, et al. LACTATE study group:

 

      Early lactate-guided therapy in intensive care unit patients: A

 

      multicenter, open-label, randomized controlled trial. Am J Respir Crit Care

 

      Med 2010; 182: 752-761

 

      8.

www.Qualityforum.org

Electronic whiskers could help robots navigate.


Photograph of several electronic whiskers used to map airf low

Researchers at the University of California, Berkeley have made highly sensitive, lightweight “electronic whiskers” that can detect the lightest of touches or a gentle breeze. Made from a mixture of carbon nanotubes and silver nanoparticles, the whiskers could be used to create “skin” for robots and in interfaces between humans and machines, says the team.

Animals use their whiskers to gauge the wind and to navigate around obstacles. The new electronic whiskers, or e-whiskers, made by Ali Javey’s team could be the next best thing to their natural counterparts in terms of size and weight. The researchers made the whiskers by painting composite films of carbon nanotubes and silver nanoparticles onto thin elastic fibres made of the polymer PDMA. The carbon-nanotube “paste” forms a conductive matrix that can be bent and unbent at will without suffering any damage. The silver nanoparticles further increase the conductivity of the composite and also make it highly sensitive to strain.

“The strain sensitivity and electrical resistivity of our composite film is readily tuned by changing the composition ratio of the carbon nanotubes and the silver nanoparticles,” explains Javey.

When the e-whiskers experience a light touch or a gentle breeze, they bend and their resistance changes dramatically. The structures are sensitive to changes in pressure of just 8% – the highest value reported to date for such tactile sensors.

Better-balanced robots

If mounted into arrays, the whiskers could be placed on robotic e-skin so that the machines are better able to navigate. They could also be used in human–machine interfaces, says team member Zhibin Yu. “They might even be ideal for some medical applications, for example in devices that monitor heartbeat and blood pressure,” he says.

The Berkeley team says that it is now looking to make the devices using different printing processes and produce them on a larger scale.

Structures such as these whiskers that mimic biological systems could help in the development of so-called smart and user-interactive electronics, explains Yu. Researchers have already made rudimentary e-skin and electronic eyes on thin, flexible substrates. Such devices are capable of “feeling” and “seeing” their local environment. “Electronic whiskers are another important class of sensor, capable of monitoring surrounding air flow and touch,” he says. “They can also spatially map nearby objects (just like naturally occurring whiskers) – a property that might help improve balance in robots of the future.”

Deficits caused by workweek sleep loss not totally recouped by sleeping in on the weekends


In many modern societies, adults often sacrifice sleep during the workweek to make time for other demands, then snooze longer on the weekends to recoup that lost sleep. Research has shown that even a few days of lost sleep can have adverse effects, including increased daytime sleepiness, worsened daytime performance, an increase in molecules that are a sign of inflammation in the body, and impaired blood sugar regulation. These last two could be partially responsible for why sleeping less negatively affects health in other ways and shortens the lifespan. Though many people believe they can make up sleep lost during the workweek by sleeping more on the weekend, it’s unknown whether this “recovery” sleep can adequately reverse these adverse effects.

To help answer this question, researchers led by Alexandros N. Vgontzas of the Penn State University College of Medicine, placed 30 volunteers on a sleep schedule that mimicked a sleep-restricted workweek followed by a weekend with extra recovery sleep. At various points along this schedule, the researchers assessed the volunteers’ health and performance using a variety of different tests.

The researchers found that the volunteers’ sleepiness increased significantly after sleep restriction, but returned to baseline after recovery sleep. Levels of a molecule in blood that’s a marker for the amount of inflammation present in the body increased significantly during sleep restriction, but returned to normal after recovery. Levels of a hormone that’s a marker of stress didn’t change during sleep restriction, but were significantly lower after recovery. However, the volunteers’ measures on a performance test that assessed their ability to pay attention deteriorated significantly after sleep restriction and did not improve after recovery. This last result suggests that recovery sleep over just a single weekend may not reverse all the effects of sleep lost during the workweek.

The study is entitled “The Effects of Recovery Sleep After One Workweek of Mild Sleep Restriction on Interleukin-6 and Cortisol Secretion and Daytime Sleepiness and Performance.” * It appears in the American Journal of Physiology-Endocrinology and Metabolism, published by the American Physiological Society.

Methodology

The researchers recruited 30 healthy adults who were normal sleepers and put them on a 13-day schedule that involved spending nights in a sleep lab. For the first four nights, the subjects were allowed to sleep for 8 hours, setting a baseline for a healthy, normal amount of sleep. For the next six nights, the researchers woke the subjects up 2 hours earlier. For the following three nights, the subjects were allowed to sleep for 10 hours. The researchers monitored the volunteers’ brain waves during these sleep sessions. At three points during the 13-day schedule, the volunteers spent whole days at the lab taking part in various tests: after the 4 days of baseline sleep, after 5 days of restricted sleep, and after 2 days of recovery sleep. On these days, the subjects had catheters inserted into their arms, and the researchers sampled blood every hour, testing it for levels of interleukin-6 (a marker of inflammation) and cortisol (a hormone secreted during stress). They also participated in a test of how quickly they fell asleep when allowed to nap several times during those days (an objective measure of sleepiness) and filled out questionnaires to assess how sleepy they felt (a subjective measure of sleepiness). To assess their performance, they participated in a test in which they were asked to press a button whenever a dot appeared on a screen, which measured how well they were able to pay attention.

Results

Not surprisingly, the researchers found that after 5 days of restricted sleep, the subjects were significantly sleepier on both objective and subjective tests compared to baseline levels. Their interleukin-6 levels increased sharply during restricted sleep, though their cortisol levels remained the same. Their performance on the attention test deteriorated. After 2 days of recovery sleep, both objective and subjective tests showed that the volunteers were less sleepy. Their interleukin-6 levels reduced, and their cortisol levels decreased significantly compared to baseline, possibly suggesting that the volunteers were sleep deprived before the study started. Notably, their performance on the attention test didn’t improve after recovery sleep.

Importance of the Findings

Though many indicators of health and well being improved after recovery sleep, these findings suggest that extra sleep may not fix all the deficits caused by lost sleep during the workweek.

“Two nights of extended recovery sleep may not be sufficient to overcome behavioral alertness deficits resulting from mild sleep restriction,” the authors write. “This may have important implications for people with safety-critical professions, such as health-care workers, as well as transportation system employees (drivers, pilots, etc.).”

The authors also suggest that even though these results provide some insight on the health effects of a single week of sleep loss and recovery, reliving the cycle over and over again may have more significant health effects that this study wouldn’t show.

“The long-term effects of a repeated sleep restriction/sleep recovery weekly cycle in human remains unknown,” they write.

United Nations to Adopt Asteroid Defense Plan.


Earth is not prepared for the threat of hazardous rocks from space, say astronauts who helped formulate the U.N. measures.

Illustration of asteroid impacting earth

When a meteor exploded over Chelyabinsk, Russia in February, the world’s space agencies found out along with the rest of us, on Twitter and YouTube. That, says former astronaut Ed Lu, is unacceptable—and the United Nations agrees. Last week the General Assembly approved a set of measures that Lu and other astronauts have recommended to protect the planet from the dangers of rogue asteroids.

The U.N. plans to set up an “International Asteroid Warning Group” for member nations to share information about potentially hazardous space rocks. If astronomers detect an asteroid that poses a threat to Earth, the U.N.’s Committee on the Peaceful Uses of Outer Space will help coordinate a mission to launch a spacecraftto slam into the object and deflect it from its collision course.

Lu and other members of the Association of Space Explorers (ASE) recommended these steps to the U.N. as a first step to address at the long-neglected problem of errant space rocks.  “No government in the world today has explicitly assigned the responsibility for planetary protection to any of its agencies,” ASE member Rusty Schweickart, who flew on the Apollo 9 mission in 1969, said at the museum. “NASA does not have an explicit responsibility to deflect an asteroid, nor does any other space agency.” The ASE advocates that each nation delegate responsibility for dealing with a potential asteroid impact to an internal agency—before the event is upon us.

The next step in defending Earth against dangerous asteroids is to find them, Lu said. “There are 100 times more asteroids out there than we have found. There are about 1 million asteroids large enough to destroy New York City or larger. Our challenge is to find these asteroids first before they find us.”

Early warning is important because it increases the chance of being able to deflect a threatening asteroid once it is found. If a spacecraft struck an asteroid 5 or 10 years before the rock was due to hit Earth, a slight orbital alternation should be enough to make it pass Earth by; if the asteroid wasn’t detected soon enough, evacuating the impact zone may be the only option available. “If we don’t find it until a year out, make yourself a nice cocktail and go out and watch,” Schweickart quipped.

The B612 Foundation, a non profit Lu founded to address the problem of asteroid impacts, is developing a privately funded infrared space telescope called Sentinel, which it hopes to launch in 2017. The telescope would begin a systematic search for hazardous near-Earth objects.

The ASE astronauts are also asking the United Nations to coordinate a practice asteroid deflection mission to test out the technologies for pushing a rock off course should the need arise. The meteor in Chelyabinsk, which injured 1,000 people but killed none, was an ideal warning shot across the bow, said American Museum of Natural History astronomer Neil deGrasse Tyson, who hosted Friday’s event—now, it’s time for Earth’s citizens to take action.  Lu agreed: “Chelyabinsk was bad luck,” he said. “If we get hit again 20 years from now, that is not bad luck—that’s stupidity.”

6 months versus 12 months of adjuvant trastuzumab for patients with HER2-positive early breast cancer (PHARE): a randomised phase 3 trial.


Background

Since 2005, 12 months of adjuvant trastuzumab has been the standard treatment for patients with HER2-positive early-stage breast cancer. However, the optimum duration of treatment has been debated. We did a non-inferiority trial of a shorter exposure of 6 months versus the standard 12 months of trastuzumab for patients with early breast cancer.

Methods

We did an open-label, randomised, phase 3 trial in 156 centres in France. Patients with HER2-positive early breast cancer who had received at least four cycles of chemotherapy, had breast-axillary surgery, and had received up to 6 months of trastuzumab (administered by intravenous infusions over 30—90 min every 3 weeks; initial loading dose 8 mg/kg; 6 mg/kg thereafter) before randomisation were eligible. Patients were randomly assigned via central randomisation procedure with web-based software to continue trastuzumab for another 6 months (12 months total duration; control group) or to discontinue trastuzumab at 6 months (6 months total duration; experimental group). Randomisation was stratified by concomitant or sequential administration of trastuzumab with chemotherapy, oestrogen-receptor status, and centre using a minimisation algorithm. The primary endpoint was disease-free survival, with a prespecified non-inferiority margin of 1·15. Analyses were done in the intention-to-treat population. This study is registered at ClinicalTrials.gov, number NCT00381901.

Findings

1691 patients were randomly assigned to receive 12 months of trastuzumab and 1693 to receive 6 months of trastuzumab; 1690 patients in each group were included in the intention-to-treat analyses. After a median follow-up of 42·5 months (IQR 30·1—51·6), 175 disease-free survival events were noted in the 12-month group and 219 in the 6-month group. 2-year disease-free survival was 93·8% (95% CI 92·6—94·9) in the 12-month group and 91·1% (89·7—92·4) in the 6-month group (hazard ratio 1·28, 95% CI 1·05—1·56; p=0·29). 119 (93%) of the 128 cardiac events (clinical or based on assessment of left ventricular ejection fraction) occurred while patients were receiving trastuzumab. Significantly more patients in the 12-month group experienced a cardiac event than did those in the 6-month group (96 [5·7%] of 1690 patients vs 32 [1·9%] of 1690 patients, p<0·0001).

Interpretation

After 3·5 years follow-up, we failed to show that 6 months of treatment with trastuzumab was non-inferior to 12 months of trastuzumab. Despite the higher rates of cardiac events, 12 months of adjuvant trastuzmab should remain the standard of care.

Source: Lancet