What causes aging and how can it be altered? According to University of Toronto researchers, the loss of our tissues’ ability to develop and repair itself can be manipulated, leading to claims that the removal of TIMPs — tissue inhibitors of metalloproteinases — could direct us toward a Fountain of Youth.
Simplified, metalloproteins are responsible for destroying and rebuilding the body’s tissue, and TIMPs control metalloproteins.
Researchers at U of T bred mice without TIMPs. They experimented with mice that had various combinations of the four TIMPs expressed.
What they found was that removing TIMP1 and TIMP3 from mice resulted in breast tissue that remained youthful in aged mice.
What was happening, the scientists discovered, was that stem cells, which usually decline with age, remained functional and abundant during the full life of the mice, so tissues maintained their ability to develop and repair.
This also resulted in less risk of breast cancer in the mice. Because the mammary glands did not degenerate as they normally would, the healthy cells were less susceptible to cancer.
Also relevant, the researchers found no increased risk of cancer, despite the larger amount of stem cells present.
The team will next attempt to push their research toward the realm of new therapeutic treatments for cancer patients through tissue remodelling.
In a finding that scientists are calling “beyond surprising,” the decades-long series of outbreaks of leukemia among clams on the eastern North American coast has been attributed the spreading of cancer from one clam to another. The finding has prompted scientists to reassess the assumption that contagious cancers are rare occurrences in nature.
“I think the story is a great example of remarkable biology lying hidden right under our noses — we just have to go looking,” Dr. Stephen Goff of the Howard Hughes Medical Institute and Columbia University told The Speaker. “It reminds us that there are many surprising aspects of nature yet to be discovered. And today we have very powerful new tools that allow us to make these discoveries.”
The team based their conclusion — that a single incidence of cancer was the root of the decades of leukemia outbreaks that have occurred off of the American and Canadian eastern coasts — on findings that the genotypes of the tumor cells come from a single line of tumor cells, not from the host animals own cells. This “rogue clonal cell line,” as the researchers put it, grew, divided, and broke free from the ground zero Steamer clam to infect others.
Dr. Stephen Goff
“That was the biggest surprise, for sure,” Dr. Goff told us. “An earlier, less exciting, surprise was the finding of the huge increase in the copy number of the Steamer retroelement in the tumors,” he added. “It’s the biggest increase in copy number of a mobile element in nature that I know of.”
The team is continuing their research, pushing to understand more about how the cancer became contagious. It is not yet known where the disease began not how the disease transmits between clams.
Locations of clam collection sites along the eastern coast
“We are actively seeking answers to the following questions: What are the mutation(s) that allow the tumor line to do this? Did the Steamer element cause these mutations? When did the original tumor arise? How long has it been spreading? Is this line restricted to the species of origin (the soft-shelled clam) or can it spread to other species? Do other species have similar tumor lines of their own?”
The transmissible cancer studied by the team is not the only known wild case, but the existence of transmissible cancer in nature has previously been considered a rare occurrence.
“We would normally expect this to be rare,” Goff told us. “We know of only two other examples in all of nature: the facial tumors of the Tasmanian Devil, and a canine venereal tumor — both are discussed in the paper, and you can read their histories. We think examples like this are rare — in vertebrates — because the adaptive immune system would recognize an invading tumor cell as foreign and reject it. The Devils do not reject these tumors for a special reason: the animals are almost all genetically identical, having gone through a small bottleneck — they almost went extinct. The dog tumor is special in lacking the surface markers that would mediate the rejection.
“But we suspect these transmissible cancers could well be more common (than we would ever have imagined) in invertebrates. They have only a primitive innate immune system, and the tumor cells must be able to evade this system and invade the new host.
Steamer clam
“For this to happen, the tumor has to have evolved to be able to exit from one diseased animal, find its way into a healthy animal — in this case, in the sea — and colonize the new animal. It’s an extreme version of metastasis, where a tumor sheds cells that seed new locations within an individual. Here the tumor is moving into an entirely new animal — not just within an animal.
“The recent research expands our conception of transmissible cancers — they exist not only on land but in a marine environment as well — and this has prompted the researchers to suspect that contagious cancers are more common in nature than we had thought.”
Women more likely to avoid harming even a single person, even if it results in thousands of deaths, research finds
Although females rationally evaluate the outcomes of actions the same as males, females make different decisions about their actions, according to recent research. Females are more strongly influenced by emotional aversion to causing immediate harm than are males, even when they believe their less harmful actions will result in greater overall harm, such as in hypothetical situations about stopping mass killers by killing or torturing them first.
“Gender differences on moral dilemmas which pit utilitarianism against deontology, seem to be driven primarily by differences in affective reactions to harm-doing, and very little, if at all, by differences in terms of cognitive evaluations of outcomes,” Dr. Rebecca Friesdorf of Wilfred Laurier University in Ontario, Canada told The Speaker.
“In other words, in this context, men and women seem to differ little in terms of how much they rationally consider the end result, but much more in terms of their emotional response to harming a single victim.”
The team of scientists, which also included members from the University of Cologne and the University of Texas, looked at data from 6,100 participants who had participated in research about high-stakes moral dilemmas, which included decisions that would result in death, lies, abortion and animal research. They team sought for differences in moral judgements between the sexes.
The team used a statistical procedure to rate and quantify the nature of the judgments.
In the recent research, the team found that females were less willing to support the killing of Adolf Hitler or torturing a bombing suspect to find explosives, although they reasoned that the actions would save more lives overall.
The researchers suspect that the reason for this is that females are more emotionally averse to the idea of themselves causing harm than are men.
“Thus, a wide range of evidence supports the dual-process model of moral judgment where affective reactions to harm motivate harm rejection regardless of the outcomes — consistent with deontological ethics — and cognitive evaluations of outcomes motivate harm acceptance when harm leads to better overall outcomes — consistent with utilitarian ethics.”
Although not the subject of their recent work, Friesdorf offered us some thoughts about how the differences in female and male decision-making might have effects in the real world.
“Although I’m not currently aware of any research which investigates gender differences in these inclinations (deontological/utilitarian) in more every-day type scenarios/dilemmas, I suspect that it is possible that they do generalize to some situations. For example, perhaps in an employment context, female managers might be more likely than male managers to be empathic/sensitive toward the potential suffering of a single employee, and therefore less likely to make a choice which greatly benefits a large group of employees, if it involves dealing great harm to the single individual.”
The report, “Gender Differences in Responses to Moral Dilemmas,” was completed by Drs. Rebecca Friesdorf, Paul Conway, and Bertram Gawronski, and was published in Personality and Social Psychology Bulletin.
Researchers at Tokyo University have added a new sense to the brains of rats. The procedure was relatively simple and the rats integrated the new sense — a geomagnetic compass — quickly. Blind rats given the new sense were soon able to navigate laboratory mazes almost as well as sighted rats. Because of the ease with which the new sense was added, researchers think many other senses can be added to the mammal brain, expanding the “colorfulness” of our experience and abilities.
“Perhaps we do not make full use of our brain.” Dr. Yuji Ikegaya of the University of Tokyo told The Speaker. “The limitation does not come from our lack of effort, but it does come from the poor sensory organs of our body. The body restricts the brain; that is, the brain has over-evolved compared to the current performance level of the body. The real sensory world must be much more ‘colorful’ than what you are currently experiencing.”
The research team added a geomagnetic compass to the senses of blind mice, and the mice were able to navigate a lab maze almost as well as mice that were not blind.
Dr. Yuji Ikegaya
“Although I do not believe that the brain is always plug-and-play ready, the brain seems to be highly adaptive and flexible so that it can perceive and use even non-inherent sense,” said Ikegaya.
The connectivity point for the new sense did not have to be specific, Ikegaya told us.
“We arbitrarily inserted two electrodes into the visual cortex. The locations of stimulation seemed unlikely to be important, because stimulation of other brain areas also worked similarly. Our head-mountable geomagnetic sensor device was designed to connect a digital compass, a microchip used normally in smart phones, to two tungsten microelectrodes for intrabrain stimulation. It is also equipped with a manipulator of stimulation intensity and a rechargeable battery. The device weights 2.5 g and thus head-mountable. During exploration of an animal, it automatically detects the head direction and thereby generates electrical stimulation pulses — for example, when the animal faces the geomagnetic north or the south.”
Ikegaya pointed to the latent, incredibly flexible potential of the mammal brain — potential that has so far been largely untapped. He expressed hope that there were many abilities that could be added to our brains.
Schematic for the process
“We expect that humans can expand their senses through artificial sensors — ‘supersensory’ organs — including geomagnetism, ultraviolet, radioactive rays, humidity, ultrasonic, radio wave, pheromones etc. Sensing sunlight UV may be important for reducing skin cancer. Also, ultrasonic and radio wave may enable a next-generation form of human-to-human communications.”
One of the most notable possibilities suggested by the study is improvements in the navigation abilities of blind people.
Usually, sound reflects off of the objects it encounters, bouncing some sound waves back in the direction from which they came — this phenomenon is familiar in the application of sonar. No technology has yet been developed that can provide sonar invisibility to any object, but a team of Singaporean researchers recently proposed a novel material surface that could do just this by directing sound waves around an object to be sent off in one direction on the other side.
The technology shares some features with topological insulators, which direct the flow of electrons along a surface, and builds on recent advances in our understanding of a class of electronic waves called “topological edge states.”
Dr. Baile Zhang
“‘Topological edge states’ are a kind of state originally found in electronic topological insulators and quantum Hall systems,” Dr. Baile Zhang of Nayang Technological University, who led the research, told The Speaker. “They are technologically promising because they are immune to backscattering from defects and disorders, similar to superconductors. But later it was found that topological edge states can also be constructed with classical waves, like electromagnetic waves and mechanical vibrations.
The proposed surface prevents sound waves from propagating through the middle of a two-dimensional triangular lattice of spinning metal cylinders. The periodic pattern of the lattice creates a sonic band gap, like other topological insulators, but it creates something else, too.
The edges of the proposed material support propagation in only one direction around the perimeter of the object. Thus, the edge states can guide sound waves with high precision.
Triangular acoustic lattice with lattice constant. Inset: unit cell containing a central metal rod, surrounded by an anticlockwise circulating fluid flow in a cylinder region of radius
“The circulating fluids can break time reversal symmetry, meaning that a wave moving forward will perceive differently from another wave moving backward,” Zhang told us.”So, we can utilize it to realize waveguiding only in one direction without reflection, no matter how large the defects are.”
That is what is key for creating stealth technology of this sort, said Zhang — the regularity of the material and guiding the flow of sound waves. “An irregular protrusion is one of the biggest headaches for stealth engineers,” he said, but coating any object with an acoustic topological insulator would guide sound waves around it in a single direction and hide that object from sonar.
“I think the most important thing is a picture of acoustic waves that can circumvent any defect or disorder, immune to backscattering from them,” said Zhang of the research.
The report, “Topological Acoustics,” was completed by Zhaoju Yang, Fei Gao, Xihang Shi, Xiao Lin, Zhen Gao, Yidong Chong, and Baile Zhang, and was published online on APS Physics.
The Ebola virus, which has taken the lives of over 4,000 people in Liberia over the past year, could be wiped out completely by the beginning of summer. It is not a foregone conclusion, but it is a realistic possibility, according to the researchers responsible for a new forecast based on new highly inclusive models.
“I think the elimination of human-to-human transmission of Ebola in Liberia by summer is probable and can be expected,” Dr. John Drake, the associate professor at the UGA Odum School of Ecology who led the project, told The Speaker. “However, as with all infectious diseases near elimination, the last mile will be one of the toughest and it would be foolish to count on elimination before it has been finally achieved.”
The work was undertaken by a joint team of ecologists from the University of Georgia and Pennsylvania State University.
“Our new method of model fitting — called the ‘method of plausible parameter sets’ — aims to quickly provide a back-of-the-envelope working model that primarily rules out inconsistent scenarios rather than quantifying the relative likelihood of alternative consistent scenarios,” Drake told us.
Their model not only estimates Ebola’s reproductive number (the number of new cases that could result from currently infected people), but also infection and treatment setting, variations in individual infectiousness, hospital capacity and burial practice changes.
Dr. John Drake
“The factors in our study are inter-related. Hospital capacity and a willingness of infected persons to be admitted are mutually reinforcing as hospitals can do nothing to isolate patients if infected persons are unwilling to be recognized and a willingness to be treated is useless without facilities that can safely treat. The safe, dignified burial of the deceased was also crucial to reducing the average number of secondary infections from a case. I believe all three were necessary for containment.”
It does not include some other factors, however. The team limited their model to what they felt was most important, ignoring superfluous data in order to achieve a usefully “intermediate complexity.”
The models used data from earlier Ebola outbreaks, factored for underreporting, in-hospital and burial transmission, and infection control effectiveness. They then added data from July through September about new cases and changes in the factors of transmission. Branching processes — a mathematical formulation that provides for all possible outcomes based on the proportion of their probabilities — was used in the models.
“Branching process theory is an area of mathematics that can be used to model contagion, reproduction, and other population dynamic phenomena that have a probabilistic component to them,” Drake explained. “We found it to be useful in this case because we could derive many of the properties of interest — like the average change in infection — from considerations about the constituent processes — like transmission from nursing care or during funeral preparations and proceedings.”
One of the biggest takeaways from the Liberian outbreak, Drake commented, was the decisions and actions of those who undertook to fight it.
“Containment required collective coordinated action. Governments, non-governmental organizations and the Liberian people are to be commended for acting swiftly and assertively. Our model predicts that if they had not, things might have gotten much worse very quickly.”
The researchers expect that their model will also be useful for future outbreak scenarios, as will their new method for model fitting.
The report, “Ebola Cases and Health System Demand in Liberia,” was completed by John M. Drake, RajReni B. Kaul, Laura W. Alexander, Suzanne M. O’Regan, Andrew M. Kramer, J. Tomlin Pulliam, Matthew J. Ferrari, Andrew W. Park, and was published in the journal PLOS Biology.
According to recent work conducted by a joint team of researchers from James Cook University, Charité-Universitätsmedizin Berlin, the Max Planck Institute for Infection Biology, the University of Heidelberg, and the National Institutes of Health, the body’s cells not only learn from the infections they encounter, becoming better able to deal with various infections throughout life, but can also remember numbers.
Dr. Andreas Kupz
“For a very long time we have tried to classify memory immune cells on overall function and morphology and have tried to group them based on such features,” James Cook University’sDr. Andreas Kupz, co-author on the study, told The Speaker. “Although this might make the wealth of information and detail more digestible, it becomes more and more clear, not just from our study, that such ‘average’ is just not good enough anymore. There is a huge heterogeneity even within individual memory immune cell subsets and in the future the focus must be much more directed towards the single cell level.”
T-helper cells, which were the focus of the recent research, help other immune cells by releasing cytokines, messenger substances.
“Our findings demonstrate that every individual T helper cell stably memorizes not only the type but also the amount of a certain cytokine it produces based on the information it receives during an initial infection,” Kupz told us. “Although we did not test the effect of this quantitative cytokine memory on a different infection, it is likely that the amount of cytokine produced will not change because the level of cytokine is predetermined through the amount of a ‘master transcription factor’ within the nucleus of the cell.”
However, T-helper cells don’t learn in the same way we understand people to learn.
“‘Learning’ in this situation is probably best translated with ‘memorizing,’ which in itself is a feature of learning. The learning occurs through maintaining a defined amount of the transcription factor that controls the production of certain cytokines. The cell-specific fine adjustments of this process is still not entirely understood but may involve the control of cytokine receptor expression and/or the activity of downstream signal transduction molecules.”
“Furthermore, we found epigenetic modifications at both the locus of the cytokine and the controlling transcription factor. Hence, we hypothesize that a combination of multiple permissive and repressive epigenetic modifications at several regulatory sites imprints the stable cytokine memory.”
Although dealing with infections does strengthen the body’s ability to deal with later infections — which might be information that could factor into arguments in the current vaccination debate — Kupz was clear that his comments were not to be on the debate, and that vaccination is something he believes is very important and necessary.
“The immunological memory that is generated through exposure to vaccines does in fact often rely on similar ‘learning’ mechanisms. ”
“In my opinion the most important take home message from this study is not so much the applicability of our findings for health and disease but more the gain in overall knowledge about T cell biology,” Kupz speculated on how his work could contribute to the growing body of information about the role of T cells, and how it could potentially lead to strengthening specific immune reactions and to reducing the misdirected immune responses that cause inflammation.
The report, “Individual T helper cells have a quantitative cytokine memory,” was completed by Caroline Helmstetter, Michael Flossdorf, Michael Peine, Andreas Kupz, Jinfang Zhu, Ahmed N. Hegazy, Maria A. Duque-Correa, Qin Zhang, Yevhen Vainshtein, Andreas Radbruch, Stefan H. Kaufmann, William E. Paul, Thomas Höfer, and Max Löhning, and was published in the journal Immunity.
A cognitive bias, the “illusion of causality,” has been explored by a joint team of scientists who found that the bias isn’t limited to false beliefs about whatever was originally learned; later on, the bias can prevent new information from being learned — even when the original information is false and the newer information is true.
Dr. Helena Matute
“Our ability to associate causes to effects is quite fallible,” Dr. Helena Matute, Professor of Psychology and Director of the Experimental Psychology Laboratory at Universidad de Deusto and lead researcher on the study, told The Speaker. “It often works well, but it very often is subject to illusions.”
The study involved two sets of student volunteers. The two groups witnessed drug treatment of different medical patients. The first group (called “high illusion”) witnessed many patients who had taken a drug — most of the patients recovered. The second group (“low illusion”) witnessed many patients who had not taken the drug — most of the patients recovered.
Both groups saw some patients who took the drug and some that didn’t, but each set saw more of one or the other. Across the board, around 70 percent of patients recovered, regardless of whether they took the drug or not.
The high illusion group more frequently concluded the drug had a helpful effect.
In a second round of experiments, both groups witnessed the same thing: half the patients received the drugs and half didn’t, and those who received the drug recovered 90 percent of the time, while those who didn’t receive the drug had only a 70 percent rate of recovery.
The high illusion group was less likely to recognize the drug’s effectiveness. The high illusion group thought that the recovery was due to the drug they had witnessed in the first phase of the study.
The researchers suspect that the high illusion group’s belief that the first drug was effective prevented the group from learning new information from the second round of experiments.
This study has relevance for false medical practices. It is important that people have exposure to true medical information early — before quackery gets a chance to reach them — Matute thinks.
“Yes, it is very important. But it might be even more important to provide people with excellent training on cognitive biases and cause-effect illusions, so that they will be interested in learning scientific methods, in general, not just related to medicine. And ideally, this should start quite early in life — maybe before 10 — and continue through life. The reason is that you cannot teach people all the details about medicine, present and future, and all the details about all other things they will need to know in their life. That is impossible. But if you teach them to think scientifically they have the tools to protect themselves against quackery and against many other frauds.
They convinced a group of teenagers that a metal wristband improved physical and mental abilities and that the teenagers should by the wristband.
The researchers next ran some the teenagers through a crash course on what had just happened. They told them about the weaknesses of the arguments in favor of the wristbands, explained the principle of baseline comparison, and taught them about causality illusion.
Afterwards, the researchers had the teenagers play a computer simulation in which the teenagers could administer a drug to patients to see if it was effective. The teenagers who had received the crash course ran more drug trials without the drug to see if the drug really was effective.
“Teaching scientific methods and scientific thinking to every one. Showing people that we are not ready to detect cause-effect relations on bare eyes, showing them that we all suffer illusions, that we often believe that A causes B when they are just co-occurring. Thus, teaching people that we need the help of controlled experiments to test whether a treatment is working. If there is no evidence supporting it, we should be aware we should not trust our personal experience, it is too biased.”
However, the illusion of causality can effect not just patients, but doctors, too.
“They are humans and are subject to identical cognitive biases as other people. They might feel that a treatment is working when it is not. But they have the scientific literature and reviews of current research to make sure whether treatment is supported by evidence.
“We need to be aware of these mistakes in order to be able to protect ourselves against them,” Matute concluded. “The only protection that we humans have developed about these cause-effect illusions is the scientific method. So, lets use it. And let’s teach everybody how to use it!”
A type of African fish that lives for only 4-6 months — ideally suited to its perpetually disappearing temporary habitat — has become a new model organism for the study of aging. Researchers at Stanford University are using new technology that allows them to edit specific genes in a series to understand some of the biggest challenges of modern biology, such as how complex characteristics like aging are encoded by genomes.
Dr. Anne Brunet
“We have created a resource to test the impact of genes on aging and age-related diseases in a rapid and high throughput manner,” Dr. Anne Brunet of Stanford University’s Brunet Lab, lead researcher of the study, told The Speaker.
“Our pipeline should allow rapid screening for genes that are important for modulating the aging process in an organism that shares a lot of characteristics with us.”
Traditionally, aging researchers have worked much with short-lived yeast, worms and other invertebrates in order to study effects across lifespan and across generations. But these creatures have little in common with humans, the primary consideration of the work of many researchers. Among the species more similar to humans, even the laboratory mouse lives 1 1/2 to 3 years.
The team used the African turquoise killifish, in which are combined both features shared with other vertebrates and relatively short lifespan — the fish complete the full course of their lives in only 4-6 months within temporary ponds of water that dry up when the seasons change in southeastern Africa.
The researchers used new genetic tools to create mutant killifish, which they have since made available to the entire research community.
“We decided to use the recently developed gene-editing technology called CRISPR/Cas9 to manipulate genes in the African killifish because this technology allows us to not only specifically delete genes, but also to precisely change a specific base pair in the genome. These are key steps in transforming an organism into a model system because they allow us to abrogate or specifically modify the function of key genes (aging and longevity genes) and then test the consequences of this on characteristic of interest (lifespan).”
The ability to edit and observe the changes of single genes is so important because a single gene can be the key to understanding the expression of many other genes.
“Lifespan is likely determined by a complex network involving many genes. That being said, it is also interesting to note that mutations in just one gene can drastically alter the aging process, which suggests that some genes are pivotal “nodes” in the network. It will be interesting to systematically dissect this network and identify the ‘hubs.'”
The wide variety of mutable killifish made available will provide scientists with fish they can screen for particular genes that may slow or speed up — or reverse — aging and age-related diseases.
“We have also developed this African killifish into a model organism that hopefully will be used by many, both in academia and industry, for potential therapies for aging or age related diseases,” Brunet told us. “Furthermore, there is an explosive amount of variations or mutations being identified in the human genome given the rise in personalized medicine (also known as precision medicine). So there is a need to understand the function of these variants at the organismal level, and this fish model could help do that in a rapid and high throughput manner.”
The sixth taste has been identified — fat. Deakin University scientists put fat through a series of tests to see if it met the strict requirements of a taste, and found conclusive evidence that fat made the grade. The findings could hold new promise in the fight against obesity.
“Research from animal and human studies provide conclusive evidence that there is fat taste,” said lead author Dr. Russell Keast, head of the Centre of Advanced Sensory Science at Deakin University. “For fat to be considered a taste it must meet some strict criteria, and it does.”
The last new taste to be recognized was umami in 1985.
Dr. Russell Keast
“Five are widely accepted: sweet, sour, salty, bitter and umami,” Keast told The Speaker. “I am saying fat has convincing evidence to be called a taste.”
Keast explained how a taste “makes it” onto the list, and how fat passed the tests conducted at his lab.
“There must be a class of stimuli — fats or the breakdown products, fatty acids — that activate receptors on taste cells. A signal must be sent from the taste cell to taste processing regions of the brain. The signal that is decoded as a perception must be independent of the other tastes — not a combination of sweet and salt or any other possible combinations.
“We have established a test to evaluate people’s threshold for fatty acid — we present 3 solutions, one of which contains a fatty acid. The task is to identify which solution contains the fatty acid. If the subject is incorrect the concentration of fatty acid is increased and the test rerun. This continues until the correct solution is identifid multiple times.”
But fat is a taste that is different from the five more familiar tastes. It is unconscious. “No actual concious taste, so no ‘sweet’ or ‘salty.’ We know fat is there, but we cannot describe what it actually is.”
That is, food with fat can be sensed, as was demonstrated in the tests, but the difference of fatty food from food without fat is difficult to describe.
This unconscious taste is not fully understood. “We know it is different from a solution without the fatty acid, but cannot describe why,” Keast said.
Keast expects more tastes will follow fat onto the list.
“There will be others, kokumi, carbohydrate, and potentially many others. As we learn more about the molecular basis of taste, perhaps we have to revise the scope and defintion for taste.”
Keast pointed to the fight against obsesity as one of the most important areas where the research could be applied.
“This has important potential in applied research — particulary the development of foods that could be lower in energy (fat) yet still deliver the important taste effects of fat. We think that the taste component of fat, which was missing in many low fat foods developed prior to the current day, did not take advantage of this knowledge.”
Animal rights activists will welcome this news with enthusiasm: the Wyss Institute at Harvard University has developed a chip that could save the lives of millions of laboratory animals. The chip would imitate the operation of complete organs and thus predict more effectively the effects of treatment on humans.
Animal experimentation is subject to much debate on the bases of both ethics and quality. Indeed, the results are rarely transferable to humans and therefore become merely the objects of a further set of tests. These experiments often create much unnecessary suffering by animals bred or kept in laboratories.
“For every dollar spent, we are getting less and less medication on the market,” Geraldine Hamilton, scientist at the Wyss Institute, commented on the current state of animal research affairs.
With the new smart chip, it could be that this waste (financial and in terms of animal lives) becomes a memory.
About the size of a coin, the new chip is composed of the cells of different organs (kidney, stomach, liver) related by small channels acting as blood vessels. In these channels, a nutritional liquid replacing blood is propelled by small pumps, reproducing the actual flow of the heart. It is an electro-organism copying reality very closely, and can therefore be used to test various substances for how they would effect the human body.
The system is not fixed, so scientists can integrate different types of cells according to the research.
The molecule to be tested is introduced into the system as if it were introduced into a body. For now, cell samples used for the first tests belong to men and women of different ethnic groups.
This new system has not yet been used in the development of any new drugs and is still in the control stage.
The research team has been distinguished by the awarding of an Animal Safety Research Prize, which recognizes innovations offering alternatives to animal testing.
In this “win-win” approach to fighting against animal and human suffering, the two are no longer opposed –they are parallel.
The prevailing assumption about dark matter is that has no interaction with light, but European physicists who investigated a possible signature of dark matter at the edges of theM101 Pinwheel galaxy now believe that light may be interacting with dark matter to produce “light halos” — detectable glows around the edges spiral galaxies.
“Dark Matter can be a lot more interactive than previously thought,” Dr. Jonathan Davis of the Institut d’Astrophysique de Paris, an author of the report, told The Speaker. “So people usually think of Dark Matter particles as neutral and so devoid of any interactions with light, but we show that this need not be the case. Also, that it is important to be creative with ways of looking for Dark Matter as no one really knows how it should behave, or where a signal will show up first.”
Dr. Jonathan Davis
“I think the idea of Dark Matter interacting with light is quite an exciting new field,” Davis told us. “Some people have looked on the effect of these interactions on the early universe. I think it would be interesting if there were future studies looking at other wavelengths of light with sensitive instruments, particularly the longer wavelengths where background light from stars should be less bright.”
The team observed the diffuse halos of light that are apparent at the outer edges of spiral galaxies — particularly the M101 Pinwheel galaxy, which they used as an example in the report.
The team theorized that light radiating from stars in that galaxy, if it was bouncing off dark matter on the outer periphery, would scatter around the galaxy in a particular way. An example used to convey the idea is that of a lamp glowing in fog.
“[The light] should be visible everywhere,” Davis stated. “The reason we focus on the edges of the galaxy is that this is where the light from stars should be dimmest. So although the DM glow is everywhere, it’s easiest to see at the edges as there is less competition with star light.
Scientists do not possess information by which the theory could be proven as of yet, and the observable patterns could also be explained as coming from other sources, Davis noted.
“At the moment there is no way of knowing if any glow is due to DM or stars. So we’re not claiming to have discovered anything yet. The galaxy we look at in our paper has a halo of older stars which make looking for a DM glow halo difficult. Indeed the glow in this case is probably due to those stars, but then you can’t rule out a DM contribution, which is what we show. However I think the emphasis should be on future dedicated searches for this light from DM scattering. If a dedicated search can separate the DM glow from other sources then they can really look for this signal, if indeed it’s there.”
Illustration of the basic principle of the team’s method. A light ray from the inner parts of the disc, where the luminosity is expected to be larger, can scatter with a Dark Matter particle in the halo, thereby altering its propagation vector. Hence, for example, the dashed blue light ray will appear to originate from the outer parts of the disc. This will compete with light which does not scatter on its way to Earth, as shown by the orange arrow. There will also be emission from a stellar halo and scattering from dust outside of the disc, which we do not show here, but whose morphology may be degenerate with our DM scattering signal.
There are several possible ways that the theory could be proven in the future, Davis explained.
“There are a few ways one could actually discovery DM-photon interactions for sure. Just through observations of galaxies if we saw a signal which had a very different dependence on the wavelength of light, compared to from stars or gas, then that would be interesting. Additionally if we discovered a signal of Dark Matter at the Large Hadron Collider or in Direct Detection experiments, that would be a big step forward.”
