In 1981, scientists discovered ways to derive embryonic stem cells from early mouse embryos. Since then, they have been the subject of intense scrutiny, controversy, and advocacy.

They are unique cells, which can be derived from human embryos and can be differentiated into virtually any kind of different cells. In humans, there are about 200 different types of cells including bone, muscle, and nerve cells, and within these cells there are about 20 different types of structures or organelles. Essentially, stem cells can be derived from human embryos, and with the right enzymes, can be stimulated. For instance, bone cells can originate from osteocyte cells, or liver tissues can come from hepatocytes.

Stem cell types and research

There are three types of stem cells:

• Embryonic stem cells
• Adult stem cells
• Induced Pluripotent Stem Cells (iPSC)

Embryonic stem cells are derived from human embryos. Adult stem cells are undifferentiated cells (meaning “clean slates” with the potential to change into another cell variant) found throughout the body after development; they multiply via cell division to replenish dying cells and regenerate damaged tissues. Induced Pluripotent Stem Cells (iPSC), which were discovered in 2006, are derived from skin or blood cells that have been reprogrammed back into an embryonic-like pluripotent state that enables the development of an unlimited source of any type of human cell needed for therapeutic purposes. While these types of cells are interesting and certainly worthy of research, this article will focus on embryonic stem cells as they are consistently the most well-known and discussed type by the general public.

Embryonic stem cells are potent and often sought after due to their abilities to proliferate without limit and contribute to any cell type. However, with great power comes great responsibility and stem cells are no exception. Poorly processed cells have been documented to mutate into cancerous tumors that can wreak havoc upon people’s bodies. Bearing this in mind, scientists also do not believe that this should derail stem cell therapies considering that there are DNA tests to check if stem cells will turn out to be problematic or not.

The stem cell project is regularly a subject of ethical debate in both the academic and public sectors. Most embryonic stem cells are derived from embryos that develop from eggs that have been fertilized in vitro—in an in vitro fertilization clinic—and then donated for research purposes with the informed consent of the donors. People willingly donate their eggs for this research, and this process does not constitute child-killing since the eggs are near their zygote phase, not a whole mature embryo. Scientists obtain those types of cells from an embryo which has not yet completed its formation to develop into a human being. Researchers then use these cells for various treatment and research purposes. It is important to stress that they are not derived from eggs fertilized in a woman’s body and that they are produced in a plastic laboratory culture via clinics in vitro.

Some examples of embryonic stem cells being used in research include the following:

1. UCLA stem cell gene therapy cures bubble baby disease

Researchers at UCLA (University of California, Los Angeles) have developed a cure for babies born with Bubble Baby Disease, a rare and life-threatening condition that can be fatal within the first year of life, by using stem cells from multiple patients and gene therapy to correct the genetic mutation of these patients.

2. Asterias biotherapeutics restores some independence to those suffering from paralysis caused by spinal cord injuries

Asterias Biotherapeutics spent much of 2016-2017 developing a stem cell therapy to restore upper body motor function to quadriplegic spinal cord injury victims. Through lengthy and rigorous testing in human clinical trials, the therapy was found to be safe for use in people with all patients treated reporting at least some improvements. Asterias is now expanding its clinical trials to include patients with sub-acute injuries.

3. UC Irvine scientists engineer stem cells to destroy cancer

In a study conducted by University of California, Irvine researchers, a stem cell-based technique was devised to find and destroy breast cancer cells that had already metastasized. The cells “feel” the stiffness of the surrounding tissues and destroy the cancer-causing cells.

Embryonic stem cells can remain undifferentiated when they are grown in a well taken care of culture that is under stable conditions. Problems primarily begin to arise if cells are allowed to clump together to form embryoid bodies in which they begin to differentiate, or change into more specific cell variants, spontaneously. Although spontaneous differentiation is a good indication that shows which cultures of embryonic stem cells are healthy, the process is uncontrolled and, therefore, an inefficient strategy to produce cultures of specific cell types.

The ability of stem cells being able to differentiate into hundreds of other types of cells continues to amaze scientists as this is no small discovery. Researchers believe that the possibilities with stem cells are near endless, especially in regard to “regenerative medicine,” the process of “replacing, engineering, or regenerating human cells, tissues, or organs to restore or establish a new function.” It is even believed that even whole organs could be synthetically grown by using them.” Additionally, stem cells have the potential to rebuild healthy tissues, help people with heart disease, diabetes, ALS, Alzheimer’s disease, liver disease, Parkinson’s disease, cancer, and many more illnesses.

In a stem cell transplant, embryonic stem cells are first specialized into the necessary adult cell type. Then, those mature cells replace tissue that is damaged by a disease or injury. This type of treatment could be used to:

• Replace neurons damaged by spinal cord injury, a stroke, Alzheimer’s disease, Parkinson’s disease, or other neurological problems.
• Produce insulin that could treat people with diabetes and heart muscle cells that could repair damage after a heart attack
• Replace virtually any tissue or organ that is injured or diseased.

Sometimes scientists use stem cells as a drug. For example, it is possible to inject a stem cell into joints to reduce swelling and pain, or in order to promote the healing processes of soft tissues. Stem cell therapy is performed by injecting the patient’s own stem cells to stimulate the body to repair and replace damaged tissue in any joint or soft tissue structures – such as knees, shoulders, hips, wrists, ankles, elbows, tendons, ligaments and non-healing bone fractures. Cellular Dynamics, a large biotechnical company, sells human heart cells called cardiomyocytes that are derived from induced pluripotent stem (IPS) cells. Pharmaceutical companies are adapting to this new and innovative trend on a day-to-day basis. Stem cells can also be used to test the quality and safety of investigational drugs by testing them on stem cells that have been transformed into tissue-specific cells. Researchers are able to monitor the side effects before exposing the drug to a patient and thus have a greater expectancy of how their body may respond to the drug. This allows us to test for cures for potentially fatal diseases in ways that would otherwise be risky or unethical.

With all of the aforementioned advantages, stem cells are a fairly new, but exceptionally promising, research area. For some people, it may seem unethical to use stem cells on the grounds that extracting stem cells damages the blastocyst, which is a structure formed in the early development of mammals, more specifically the sixth or the eighth day of the development of an embryo. In 2006, President Bush vetoed the Stem Cell Research Enhancement Act stating that the federal government should not support “the taking of innocent human life.” Although stem cells are very promising for science and can open new doors to many new treatments in the medical field, it looks like there are still differences of opinion on their ethical use. This is perhaps because there is need for more convincing evidence or people are not informed accurately on the details of this research area.

References

• https://stemcells.nih.gov/info/Regenerative_Medicine/2006Chapter1.htm
• https://www.healthline.com/health/stem-cell-research
• https://www.statnews.com/2017/04/26/stem-cells-cancer-mutations/
• https://plato.stanford.edu/entries/stem-cells/
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5398703/
• https://www.mayoclinic.org/documents/the-amazing-stem-cell/doc-20249792
• https://www.unmc.edu/stemcells/educational-resources/history.html
• https://www.cirm.ca.gov/patients/power-stem-cells
• https://www.nature.com/news/stem-cells-take-root-in-drug-development-1.10713
• https://hsci.harvard.edu/examining-ethics-embryonic-stem-cell-research#:~:text=Opponents%20argue%20that%20the%20research,taking%20of%20innocent%20human%20life.%E2%80%9D

Think of yourself as a desert ant. You leave your nest to search for food early in the morning in the deserts of Tunisia, except you do not know where to find food. You, therefore, walk randomly in the desert in a circuitous outward path from your nest until you find food. If you would find food, how do you get it back to your home? How do you go back without having left for yourself any traces or signs in the wasteland, without knowing where you located, and most importantly, without ending up stranded in the scorching heat of the desert? Could you accomplish coming back each day with food? Well, desert ants can.

To find out how ants can do this, scientists observed their behavior, and surprisingly they have found that ants did not follow back on the same trail they randomly took after they left their nests. Instead, ants took a direct route as if they already knew where the nest exactly located. How do these ants find the closest way and shortest distance to their nest from their current locations? Former studies had found that red and forest ants secrete a chemical substance to mark their paths. They leave a trail of chemical scents or visual traces behind them—like leaving a trail of breadcrumbs to help you find your way home. However, the structure of desert sands and conditions are not consonant with containing chemicals that will carry an odor or leave visual cues. Even if such markings have made, it is hard to guarantee that they will remain intact long enough considering the harsh conditions of the desert. As in Hansel and Gretel fairy tale kids who could not return home for the breadcrumbs they had left on the trail eaten by birds. Therefore, these desert ants must be equipped with another cognitive mechanism so that they can return to their nests before succumbing to the midday heat.  

Black desert ants (Cataglyphis fortis) emerge from their nests in the heat of desert sand, which rises to 70 degrees with the rise of the morning sun, to search for the remains of other insects that were not as heat resistant as they are. They can only survive for one hour on the hot sand and under the blazing sun, which means that within an hour, they must find their food and bring it back home without getting lost. The journey is quite arduous and dangerous each day. If the slightest confusion occurs and they are not able to return to their nest in time, then it could cost them their lives.

Scientists conducted a series of research in the scorching deserts of Tunisia to find out how desert ants take their food to their nests in the shortest route possible. Researchers first determined an anthill and plotted the terrain around it to set up a coordinate plane. They observed that the ants left their nests very early in the morning to begin their daily search for food, and many of them eventually found grubs that had been planted by the scientists. However, researchers moved the ants to locations that they had not previously been to after the ant began carrying the food back to their nests. The attempt was to understand whether there was a “sign placement system” within the ants. This system would encourage the ant to find its last known location, in this instance where it had picked up, then find its way back home. However, the ant instead began heading directly to its nest. It was as if the ant determined its position concerning its nest and set off for it immediately. This experiment was repeated on many ants numerous times and with the same consistent results. The ants, as soon as they had placed on the ground, moved to the nest relative to there. With a wondrous intrinsic coding of some neurons in their nervous systems, they traveled the distance between their new location and the nest in the shortest way possible. In addition to this, the margin of error was very nominal; they found their nests with a ten percent error in the average distance of 500-meters and with an error of only two degrees in angle. Additionally, a fascinating discovery revealed that the ants could calculate errors in their navigation systems. As they approach their destination, they would make adjustments if they need to by moving back and forth in parallel lines to reach the nest with minimum error.

Scientists determined that desert ants have about a thousand lenses in their compound eyes (remember that a human eye has only one lens) and 80 lenses in each of their eyes that can detect polarized light that comes from different points in the sky. Polarized light occurs when sunlight enters the atmosphere of Earth, hits air molecules and other particles, and then scatters in all directions. This dispersion leads to polarization, and the light that starts to vibrate in many planes begins to vibrate in only one plane. Therefore, the strongest of them is a distinct polarization that always makes a 90-degree angle towards the sun. The lens system in the eyes of desert ants uses this polarization to form a kind of Sky Map. These ants will occasionally stop and robotically move their heads while returning to their nest. This brief period allows the ants to make this sky map by surveying the sky and making a mental note of its layout. Researchers believe that ants can then calculate the direction that they need to travel to return to their nest. They repeat this movement along the way to continually update their sky maps. If they cannot find their home, then they utilize a patterned search method with a set of circular motions. It means that each ant knows how far it is from their nest at every point of their journey.

Then, how do ants find their direction to the nest? Perhaps they were guided by the position of the sun in the sky is. To test this hypothesis, researchers placed a set of mirrors to make ants perceive the sun in a different state than where it ordinarily would be. It observed that the ants changed their directions according to the new state of the sun. However, this finding raised another question; researchers wondered how the time of day would affect the ants since the sun moves across the sky during the day. However, this finding raised another question; researchers wondered how the time of day would affect the ants since the sun moves across the sky during the day.

In another part of the experiment, the researchers caught the ants after they found the bait, closed a box over them, and kept them inside the box for several hours so that they could not see the sun and its movements. It expected that the ants would have trouble finding their way back after they were released since a long time had passed, and the sun was in a drastically different position in the sky. However, they once again returned home by using the shortest distance possible. It understood that the desert ants were aware that time was passing even though they could not see the sun.

We now understand that ants determine their direction home by using the sun, but we still do not know how they figure out the distance they must travel to return to their nest. Researchers have developed three hypotheses to explore this phenomenon. The first hypothesis was the energy hypothesis. According to this hypothesis, the ants were able to know how much energy they needed on the way back by calculating it they had spent until they reached their food. The depletion of their energy meant the end of their journey. An ant loaded with extra weights to test this hypothesis as soon as it reached its food. The scientists thought that if their body weight increased, then they would not be able to strike reach the nest since they would spend more energy on the return trip. However, in this case, it did not affect the ants, and they returned home in the shortest way possible regardless of their weight.

The second hypothesis was the optical-flow hypothesis. In this hypothesis, it believed that the ants had visual memory, and this was how they remembered the way back. To prove this, scientists prevented the ants from seeing their surroundings by blindfolding the ants when they found their food source. However, the blindfold did not prevent the ants from obtaining the shortest distance back home. As a follow-up to this experiment, the researchers placed an extensive television screen in front of the ants showing an endless desert on the television screen to make the ants feel as if they had crossed the entire desert in this simulation. They used various types of simulations, but the result did not change; the ants found their way.

The last test involved the pedometer hypothesis. It surmised that ants could be counting their steps to determine how far they had traveled. To test whether they were doing so, researchers attached stilts made of hair strands to the legs of one group of ants after they found the food. As their legs now extended, they could move with longer scale steps. Another group of ants had their legs cut below the knee, thus shortened to increase the number of steps needed to walk the required distance back. They then observed the return journey of both groups of ants. The results were astounding; the ants with shorter legs had concluded their course before reaching the nest, while the ants with longer legs ended up passing the nest. Thus, it understood that the ants counted their steps according to the distance they traveled.

The findings reveal that the ants are created with an internal system that keeps track of the steps they take and re-calibrates itself on the way back. People make these complex calculations with measuring instruments and by knowing the laws of trigonometry. However, these small creatures find their way directly back without using any tools or computer applications. They do not use their perception to find direction, and they do not use any other directional methods because they all remember direction and distance as they move forward. If you look at this situation, what would be your simplest explanation? You can only have one definition: These little creatures can measure distances and angles precisely by applying mathematical calculations and trigonometry within their conditions. Since the first day of their existence, these creatures show only a few of the shreds of evidence of the divine power created them out of nothing with wondrous systems and superior abilities in their bodies.

I have put my trust in God, my Lord, and your Lord. No living creature is there, but He holds it by its forelock and keeps it under His complete control. Undoubtedly, my Lord is on a straight path (He governs all that exists and carries out His decrees rightly and with absolute justice). (Surah Hud, 56)

Nose cells as the key COVID-19 entry point

Sungnak et al. SARS-CoV-2 entry factors are highly expressed in nasal epithelial cells together with innate immune genes. Nature Medicine, April 2020.

The coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Detection of the virus was first reported in Wuhan, China and has since spread worldwide and emerged as a global pandemic. COVID-19 primarily affects the lungs and airways and has a wide range of symptoms including fever, coughing, and sore throat. One of the scariest aspects of the virus is that some people may not manifest symptoms but can still carry and spread it. In severe cases, the virus causes pneumonia that can ultimately lead to death. Studies suggest that the virus is thought to be spread through respiratory droplets produced when an infected person coughs or sneezes and appears to be easily transmitted within affected areas. COVID-19 has spread to more than 184 countries and claimed more than 190,000 lives so far. One of the major questions scientists around the world are trying to understand is how the virus spreads, how we can prevent transmission, and how we can develop an effective vaccine. To discover the target cells involved in COVID-19 transmission, scientists analyzed the gene expression profiles of thousands of cells from 20 different human tissues including the lung, nasal cavity, eye, gut, heart, kidney, and liver. They specifically looked for individual cell types that expressed both of two key COVID-19 entry proteins – the receptor protein ACE2 and the TMPRSS2 protease. These analyses revealed that mucus-producing goblet cells and ciliated cells on the inner lining of the nose have the highest level of COVID-19 virus proteins of all cells in the airways. While there are many external and internal factors that contribute to the virus’ transmissibility, these findings are consistent with the rapid infection rates of the virus. The location of these cells on the surface of the inside of the nose makes them highly accessible to the virus and also may assist with transmission to other people. Interestingly, ACE2 and TMPRSS2 were also found in cells in the cornea of the eye and in the lining of the intestine. This suggests another possible route of infection via the eye and tear ducts, and also revealed a potential for fecal-oral transmission. These findings have important implications for understanding viral transmissibility and could have critical translational implications. For example, given that nasal carriage is likely to be a key feature of transmission, drugs and vaccines administered intra-nasally could be highly effective in limiting the spread of the virus.

Neutrinos Could Explain Why the Universe Has So Much More Matter Than Antimatter

The T2K Collaboration. Constraint on the matter–antimatter symmetry-violating phase in neutrino oscillations. Nature, April 2020

The current laws of physics propose that 13.8 billion years ago, at the time of the Big Bang, every particle of matter had been created with a counterpart called antimatter. Antimatter is precisely the same as matter but with an opposite physical property such as an electrical charge. The great mystery for physicists is why there is so much more matter than antimatter in the universe. If there had been equal quantities in the beginning then each particle would have wiped each other out in a blaze of energy and left the universe full of just photons and dark matter. To understand the mystery behind this asymmetry, scientists have utilized an experiment known as “T2K.” T2K is a collaboration between 500 international scientists that employs a proton accelerator in Japan that generates beams of subatomic particles called muon neutrinos and antineutrinos which then travel 295 km to the gigantic Super-Kamiokande detector, located in a tank filled with 50,000 tons of water under a mountain in Kamioka on Japan’s west coast. During this trip, the muon neutrinos and antineutrinos change in flight to electron neutrinos and antineutrinos, demonstrating the phenomenon of neutrino oscillations. The team observed for the first time that there is a significant difference between neutrino and antineutrino oscillations. Neutrinos were found to turn into electron neutrinos at a much higher rate than their antineutrino counterparts and, as a result, would propagate regular matter at a higher rate than antimatter. These results show that although matter and antimatter look so similar to each other, they can behave completely different. Previously, scientists have found some differences in behavior between matter and antimatter versions of other subatomic particles called quarks, but the differences observed did not seem to be large enough to account for the dominance of matter in the universe. This new data indicates that subatomic particle neutrinos might be the very reason the universe is dominated by matter. While the scientific community is very excited about these results, most experts suggest collecting a lot more data in order to get the confidence level of their results up over the current ratio of 95%.

Humans Tend To Go With Our “Gut Feelings” Over Evidence-based Decisions

Konovalov& Krajbich. Mouse tracking reveals structure knowledge in the absence of model-based choice. Nature Communications, April 2020.

A new study showed that when faced with a decision, humans prefer to follow their “gut feeling” or habits instead of taking all facts into account. In the study, participants played a simple computer game in which identifying patterns could make them more money. While following the patterns led to success most of the time, there was still a 10-40% chance that it would not give the best outcome. The researchers observed that 56 of the 57 participants were able to identify the pattern to make the decision that gave them the highest chance of success. However, only about 20% of players consistently went with that choice after it failed them. The other 80% of players diverged and made choices based upon their gut feelings. The researchers suggest that participants decided to go with their gut feelings when making in-game decisions because choosing the best pattern only led to a slightly higher chance of success. This study highlights how decision-making works in real life. People can learn what choices lead to the best outcomes; but putting that knowledge into practice can often be difficult as it likely takes a lot of mental and sometimes physical energy to always make decisions based upon your knowledge of your current environment. Moreover, the rewards of following the best strategy aren’t always obvious in real life. Following a familiar strategy may increase your success by only a small percentage. In our decision making, there is always the dilemma – what we should do from a statistical perspective versus what worked out well recently, typically in an anecdotal manner.

Andersen KG et al. The proximal origin of SARS-CoV-2. Nature Medicine, March 2020.

Cases of Covid-19 first emerged in December 2019, when a mysterious illness was reported in in the city of Wuhan, China. The cause of the disease was soon confirmed as a new kind of coronavirus, and the infection has since caused a large-scale epidemic and spread to more than 70 other countries. Coronaviruses are a large family of viruses that are related to a broad spectrum of illnesses, the first of which was the 2003 Severe Acute Respiratory Syndrome (SARS) epidemic in China. A second outbreak of severe illnesses began in 2012 in Saudi Arabia with the Middle East Respiratory Syndrome (MERS). On December 31 of 2019, Chinese authorities alerted the World Health Organization of an outbreak of a novel strain of coronavirus named SARS-CoV-2 causing severe illness. As of February 20, 2020, nearly 167,500 Covid-19 cases have been reported, though many milder cases have likely gone undiagnosed. More than 6,600 people have already died as a result of contracting this virus – and the numbers will be much higher when you will be reading this article. Chinese scientists sequenced the genome of SARS-CoV-2 very shortly after the epidemic began and made the data available worldwide. The analyses of genomic sequence data have shown that Chinese authorities rapidly detected the epidemic and that the number of Covid-19 cases have been increasing because of human to human transmission after a single introduction into the human population.

Recently, a group of scientists used this sequencing data to explore the origins of SARS-CoV-2 and how it has become the version that it is now. The scientists specifically focused on the genetic codes for spike proteins, the mechanical framework on the outside of the virus that it uses to grab and penetrate the outer walls of human and animal cells. There are 2 major parts of the spike proteins: the receptor-binding domain (RBD), a molecular hook that grips onto host cells, and the cleavage site, a molecular can opener that allows the virus to crack open and enter host cells. The scientists found that the RBD portion of the SARS-CoV-2 spike proteins mutated to effectively target a molecular feature on the outside of human cells called ACE2, a receptor normally involved in regulating blood pressure. The SARS-CoV-2 spike protein was exceptionally effective at binding to human cells, and the scientists concluded this could only be a product after a natural selection process and not the product of human-designed genetic engineering. This evidence was further strengthened by data on SARS-CoV-2’s backbone molecular structure. If someone were to engineer a new coronavirus as a pathogen, they would have constructed it from the backbone of a virus known to cause illness. But the scientists found that the SARS-CoV-2 backbone differed substantially from those of already known coronaviruses and mostly resembled related viruses found in bats and pangolins. These two features of the virus, the mutations in the RBD portion of the spike protein and its distinct backbone, basically ruled out laboratory manipulation as a potential origin for SARS-CoV-2. Based on their genomic sequencing analysis, scientists came up with two possible scenarios as the most likely origins for SARS-CoV-2.

In the first scenario, the current pathogenic state of SARS-CoV-2 has emerged naturally in non-human hosts such as bats or pangolins and then jumped to humans. Coronaviruses are well known to undergo genetic recombination. In fact, this is exactly how previous coronavirus outbreaks have emerged, with humans contracting the virus after direct exposure to civets (SARS) and camels (MERS). The researchers proposed horseshoe bats as the most likely reservoir for SARS-CoV-2 as it is very similar to a bat coronavirus. There are no documented cases of direct bat-human transmission so far, suggesting that an intermediate host was likely involved between bats and humans.

In this particular scenario, both of the distinctive features of SARS-CoV-2’s spike protein and the cleavage site would have mutated to their current pathogenic state prior to entering humans. In this case, the current epidemic would probably have emerged rapidly as soon as humans were infected, as the virus would have already equipped with the features that make it pathogenic and able to spread between people.

In the second proposed scenario, a non-pathogenic version of the virus jumped from an animal host into humans and after a mutation process it has acquired its current pathogenic state within the human population. For instance, some coronaviruses from pangolins, armadillo-like mammals found in Asia and Africa, have a spike protein very similar to that of SARS-CoV-2. A coronavirus from a pangolin could possibly have been transmitted to a human, either directly or through an intermediary host such as civets or ferrets.

In this scenario, only the cleavage site could have mutated within a human host, possibly via limited undetected circulation in the human population for months or maybe years prior to the beginning of the epidemic. The researchers found that the SARS-CoV-2 cleavage sites have similarities that resemble strains of bird flu that can transmit easily between people. In the case of SARS-CoV-2, such a virulent cleavage site could have been formed in human cells and soon the current epidemic got initiated, as the coronavirus would possibly have become far more capable of spreading between people.

At this point, it is almost impossible to know for sure which of the scenarios is most likely. If the SARS-CoV-2 entered humans in its current pathogenic form from an animal source, it raises the probability of future outbreaks, as the illness-causing strain of the virus could still be circulating in those animal populations and might come back to humans again. It is still noteworthy that a non-pathogenic coronavirus entering the human population and then acquiring properties similar to SARS-CoV-2, the second scenario, is less likely than the first scenario.

In conclusion, this study brings an evidence-based view to the baseless rumors and conspiracy theories that the SARS-CoV-2 was deliberately manufactured in a lab and concludes that the virus has emerged after a natural process that took place in multiple hosts over time. These genetic findings are also consistent with how SARS-CoV2 is currently behaving. The virus has a low fatality rate (1% to 3.4%) and does not seem to act like a bioweapon compared to pathogens such as anthrax or Ebola. Given the previous coronavirus epidemics and the persistence of the culture of eating exotic mammals in China and other parts of the world, the current COVID19 epidemic is unfortunately not a big surprise for scientists and experts. We have to take necessary measures to be more prepared for such outbreaks that may take place in future.

Hsueh MF et al. Analysis of “old” proteins unmasks dynamic gradient of cartilage turnover in human limbs. Science Advances, October 2019.

Humans may not be able to regrow amputated limbs, but a recent study showed that damaged cartilage may regrow through a process similar to that of animals such as salamanders and zebrafish. Scientists collected 18 specimens of joint tissue from the hips, knees, or ankles of patients who underwent surgery. They then placed the tissue in a mass spectrometer and measured the age of the cartilage proteins in the sample. These analyses showed that the age of cartilage largely depended on where it resided in the body. Cartilage in ankles is young, middle-aged in the knee, and old in the hips. This correlation between the age of human cartilage and its location in the body suggests that limb repair occurs in humans in a similar fashion to certain animals in which tissue regeneration takes place at the furthest tips such as the ends of legs or tails. This finding also helps to explain why injuries to people’s knees and, especially, hips take a long time to recover and often develop into arthritis, while ankle injuries heal quicker and less often become severely arthritic. The researchers further identified the molecules that are instrumental in the regulation of this region-specific regeneration process. They are called microRNAs and, not surprisingly, are present at very high levels in animals that are known for limb, fin, or tail repair including salamanders, zebrafish, and lizards. Scientists believe that these regulator microRNAs can be utilized in the regeneration of degenerated cartilage of an arthritic joint to reverse arthritis. Regeneration of part or all of an injured human limb may even be possible by finding components salamanders have and we don’t. Finally, it is also possible that this could be a fundamental mechanism of repair that could be applied to many tissues, not just cartilage, which might open up many new avenues in the regenerative medicine.

The universe might have many Earth-like exoplanets

Doyle AE et al. Oxygen fugacities of extrasolar rocks: Evidence for an Earth-like geochemistry of exoplanets. Science, October 2019.

New astrophysical and geochemical evidence suggests that Earth may not be that unique, and Earth-like planets may be common in the universe. All of the planets in our solar system orbit around the Sun. Planets that orbit around other stars are called exoplanets.  The first exoplanets were discovered in the early 1990s. Since then, thousands of exoplanets have been revealed with over 4,000 confirmed and a further 4,495 potential candidates. There have been major efforts to narrow down the exoplanets that may have properties similar to Earth with conditions suitable for life. This includes being a rocky planet that is not too hot or cold so that liquid water can exist. When searching for exoplanets that are similar to Earth, astronomers typically look for worlds in orbit around a type of star called a red dwarf or an M-dwarf. These types of stars are somewhat similar to our sun and make up about 70% of the stars in our galaxy. However, a new study shows that rocky exoplanets in orbit around a different type of star, a white dwarf, can have interiors that are surprisingly similar to our planet. White dwarf stars are dense remains of normal stars that have exhausted their nuclear fuel. These stars are typically composed of light elements such as hydrogen and helium, but in some cases they attract heavier elements such as magnesium, iron, and oxygen in their atmospheres due to their extreme gravity. These heavy elements are thought to be introduced when a rocky exoplanet crashes into a star, which gives astronomers evidence of what the exoplanets were like before they were destroyed. In this recent study, scientists looked at six white dwarfs located 200 to 665 light-years from Earth and rocks from the planets that once orbited it. Their analyses showed that five out of the six white dwarfs had sucked up fragments whose chemical composition is similar to rocks on Earth, Venus, and Mars. While the conditions suitable for life depend upon many additional factors, this study points towards the idea that many rocky planets are likely very familiar in terms of their general composition and, therefore, structure and behavior. This study also made a substantial leap forward in being able to make inferences for bodies outside of our own solar system and indicates that it is very likely that there are truly Earth analogs out there.

Artificial leaf points to a sustainable path to carbon-neutral fuels

Andrei V et al. Bias-free solar syngas production by integrating a molecular cobalt catalyst with perovskite–BiVO4 tandems. Nature Materials, October 2019.

An artificial leaf from which a “clean” fuel alternative to petrol could be produced has been developed. Synthetic gas can be obtained from the lead by using only sunlight, carbon dioxide, and water.

Synthetic gas, also called syngas, is typically a mixture of carbon monoxide and hydrogen. It is largely produced by exposing fossil fuels such as coal or natural gas to high temperature steam and pressure, and the process releases carbon dioxide. Syngas is broadly used in a wide range of commodities including fuels, plastics, and fertilizers. While the utilization of fossil fuels has enabled large-scale industrial development in human history, the burning of fossil fuels is the largest source of emissions of carbon dioxide, which is one of the greenhouse gases that contributes to global warming. For decades scientists have been trying to discover new ways to produce syngas in order to close the global carbon cycle and to establish a sustainable chemical and fuel industry. In a recent study, researchers got inspired by leaves. These perfect little machines use sunlight to convert carbon dioxide and water into fuel for plants through photosynthesis. An artificial leaf has been designed to have two light absorbers, similar to the molecules in plants that harvest sunlight, and a catalyst made from the naturally abundant element cobalt. When the leaf is immersed in water, one light absorber uses the catalyst to produce oxygen and the other one carries out the chemical reaction that reduces carbon dioxide and water into carbon monoxide and hydrogen, thus forming the syngas mixture. The scientists are now searching for ways to use their technology to produce a sustainable liquid syngas that could serve as an alternative to petrol. Although major efforts to generate renewable energy sources are being made, the development of synthetic petrol is critical as electricity can currently fulfill about 25% of our total global energy demand. There is a huge demand for liquid fuels to power heavy transport, shipping, and aviation sustainably.

The parable of those who take to them other than God for guardians (to entrust their affairs to) is like a spider: it has made for itself a house, and surely the frailest of houses is the spider’s house. If only they knew this! (Qur’an, 29:41)

A prehistoric Greek fairytale says a young girl named Arachne was a superb spinner and knitted the most gorgeous cloth. She dared the goddess Athena to a competition. When Athena saw Arachne’s stunning work, she ripped the cloth and hit the young girl. Disgraced, Arachne committed suicide by hanging herself. Athena regretted and transformed Arachne into a spider, so that she could whirl repeatedly and endlessly. Arachnida is the scientific name for spiders. It comes from the young girl in the famous Greek fairytale.

Although usually feared and disliked by people, spiders in fact make life easy for us by feeding on mosquitoes, flies, and locusts, thus saving our crops and eliminate the need for man-made insecticides which pose environmental problems. Besides, spiders are much less dangerous than people think they are; most spiders are keen to avoid interaction with people and will bite only when wounded or scared. Even poisonous spiders are rarely as dangerous as popular myths would have us believe: though black widows are poisonous, and their bites painful, they rarely kill people. If handled properly and quickly the adverse consequences of a black widow’s bite typically diminish in a few hours, and, after a couple of days’ rest or cessation of activities, the victim will fully recuperate [1].

There are countless features of spiders. But their silk is exceptionally unique and this article covers its various aspects.

Spider silk

Biomaterials, having developed over millions of years, frequently surpass man-made substances in their properties. Spider silk is an exceptionally stringy biomaterial which is made almost completely of substantial proteins. Silk fibers have stretchy powers similar to steel and some silks are practically as elastic as rubber on a weight-to-weight basis. In uniting these two properties, silks disclose a hardiness that is two to three times that of artificial fibers like Nylon or Kevlar. In addition, spider silk is also antimicrobial, hypoallergenic, and completely biodegradable [2].

The power of spider silk, so fragile in manifestation, is astonishingly great. A filament can be outstretched as much as one half its normal length before breaking, and has a tensile strength exceeded only by fused quartz fibers. Fine fibers are sturdier than others, the power to some degree depending on the velocity with which they are pulled out of the spider’s body. The higher the speed, the superior the strength.

Most of the silken fibers are not single fibers but are made up of two or more strings. A thread may be as fine as a millionth of an inch in width but, frequently, it is ten or twenty times as dense, and the assemblage of these threads unsurprisingly creates larger threads of a diversity of thicknesses. Furthermore, some threads are gluey whereas others are not.

Scientific research demonstrates that a single thread of spider silk, thick as a pencil, could stop a 747 Jumbo Jet in flight, and that on an equivalent footing, the spider’s silk is stronger than steel, per unit weight. It has been shown that the dragline silk of the golden orb spider is one of the planet’s hardest threads.

Spiders employ silk for webs, but also for trap lines, draglines, ballooning lines, for egg pouches and nursery nets, for compartments in which to sleep through winter or to copulate, and for entrapping and wrapping their victims. Silk for all these objectives is not accomplished with one kind of gland; there are at least seven distinct kinds. A few distinctive spiders have as many as six kinds and probably have more than six hundred independent glands; others have fewer than this [1].

Mechanism behind the formation of spider silk

A batch of scientists headed by researchers from the RIKEN Center for Sustainable Resource Science (CSRS) have scrutinized spider silk and discovered that a formerly undiscovered organizational constituent is critical to how the proteins form into the beta-sheet conformation that gives the silk its extraordinary power [3]. If humans can cultivate equivalents to spider silk, they could be applied in industrial and medical applications. It is well-known that the beta-sheets in spider silk are significant to its strength, but how the sheets are created is scantily comprehended, making it difficult to produce synthetic variations. It is hard to comprehend the process: the silk is originally produced as soluble proteins, which very swiftly crystalize into a solid form.

To explain this, the CSRS scientists obtained silk proteins using genetically altered bacteria that can generate silk from a golden orb-web spider (Nephila clavipes) and then executed multifaceted examinations of the soluble proteins. They discovered that the reiterating area is comprised of two designs – unsystematic spirals and a design called polyproline type II helix. Their investigations confirmed that the polyproline type II helix is critical for the creation of the stiff construction, which can then be rapidly converted into beta-sheets, letting the silk be swiftly intertwined. Fascinatingly, it was discovered that pH – which is supposed to be significant for the molecular exchanges of the N- and C- terminus areas – does not play a significant role of the foldup of the recurring areas, and that it is rather the elimination of water and mechanistic forces through the silk gland.

According to Keiji Numata, who is a project leader of JST ImPACT and led the research group, “Spider silk is a wonderful material, as it is extremely tough but does not contain harmful substances and is readily biodegradable, so it does not exert any harmful load on the environment” [4]. Numata hopes that this discovery may lead to the production of artificial silk that will prove useful for society.

Analysis of silk

The silk itself is a material identified as a “scleroprotein.” When created in the glands it is a fluid; only when dragged outside the body does it solidify into thread. Once it was believed that contact with air produced the toughening, but it currently looks that the drawing-out activity alone is accountable for the change.

To carry out the exertion done by the glands, a spider is armed with spinnerets, usually six in number. These are as accommodating as fingers; they can be prolonged, compacted, and overall be applied like human hands. In the “spinning field,” where the spinnerets are congregated, single threads are joined into numerous compound threads, and some of the dehydrated threads may be covered with a gluey substance. Thus, a completed thread may be thin or thick, dry or sticky. It may also have the look of a bead-trimmed necklace. For the last kind, the spider spins rather unhurriedly and, drawing out the gluey thread, lets it go with a jolt. The liquid thus is organized in beads spread out lengthwise across the completed line.

The strand known as the dragline may be understood as a spider’s “life line” because it performs as a lifeguard in all kinds of situations. The dragline goes along with the spider, no matter where or how far it journeys, winding out from spinnerets at the back of the body. It forms a portion of the building of webs, it grips its tiny builder firmly in problematic places, and it helps in absconding from adversaries. When a spider is inactive in a web, the dragline enables a rapid descent and escape. It allows energetic chasing spiders to jump from buildings, cliffs, or any tall position with absolute security. [1]  

Benefits of spider silk to us

The silk of the silkworm could be very profitable and marketable. There are, however, challenges. One is the changing thickness of a spider’s strand; the other is that it doesn’t well endure the interweaving process. Housing and feeding large numbers of silkworms is not difficult. But housing and feeding large numbers of spiders? There are enormous difficulties.

Native inhabitants of New Guinea have used spider silk in a variety of conditions. They make fishing nets, traps, and such objects as bags, headdresses that will keep away rain, and caps. These are not formed from single threads but from tangled, warped threads. The aboriginals of North Queensland, Australia, look to spiders for their angling supplies.

Spider silk has been valuable to the manufacturers of such complex instruments as astronomical telescopes, guns, and engineers’ levels. The threads, being exceedingly fine but nonetheless robust, are outstanding for sighting marks. Throughout the Second World War, there was a significant demand for spider thread for surveying and laboratory instruments. Black widow spiders were utilized for the manufacture of this silk.

One drawback to the use of spider silk in industry is that it might slump in a moist environment. To overcome this problem, strands of platinum or etching on glass plates take its place in such instruments as periscopes and bombsights. [1]

Spider’s silk also might have healing properties. Due to its antibacterial properties and because the silk is abundant in vitamin K, it may be efficient at clotting blood. Because of the problems in obtaining and handling extensive amounts of spider silk, the largest known piece of cloth made of spider silk is an 11 by 4-foot (3.4 by 1.2 m) fabric made in Madagascar in 2009. Eighty-two persons labored for a period of four years to gather over one million golden orb spiders and extract silk from them. [5]  

Applications of spider silk

As mentioned, human beings have been using spider silk for thousands of years.

The manufacture of contemporary synthetic super-fibers such as Kevlar (bulletproof material) includes petrochemicals, which adds to pollution. Kevlar is also strained from concentrated sulphuric acid. In comparison, the manufacture of spider silk is totally ecologically sustainable. It is created by spiders at ambient temperature and pressure and is strained from water. Furthermore, silk is totally biodegradable. If the manufacture of spider silk ever becomes industrially practical, it could be a substitute for Kevlar and be used to create a varied extent of articles such as: bulletproof vests, wear-resistant lightweight clothing, ropes, nets, seat belts, parachutes, rust-free boards on motor vehicles or boats, biodegradable bottles, bandages, surgical thread, artificial tendons or ligaments, and backings for weak blood vessels. [6]

Synthetic spider silk [5]

Duplicating the multifaceted settings needed to make threads that are similar to spider silk has been difficult to both research and manufacture. Through genetic engineering, Escherichia coli bacteria, yeasts, plants, silkworms, and animals have been utilized to produce spider silk proteins. Yet, these synthetic threads have diverse, simpler features than those of a spider. Manmade spider silks have lesser and unsophisticated proteins than natural dragline silk, and have subsequently half the diameter, strength, and flexibility.

One tactic is to remove the spider silk gene and utilize additional life forms to generate the spider silk. Canadian biotechnology company Nexia effectively produced spider silk protein in transgenic goats that passed the gene for it; the milk made by the goats comprised noteworthy amounts of the protein: 1-2 grams of silk proteins per liter of milk. To make spider silk, Nexia utilized damp whirling and pressed the silk protein across minor extrusion cavities in order to mimic the performance of the spinneret, but this process was not adequate to duplicate the sturdier characteristics of innate spider silk.

In March 2010, investigators from the Korea Advanced Institute of Science and Technology was able to produce spider silk by means of the bacteria E. coli, altered with definite genes of the spider Nephila clavipes. This tactic removes the necessity of milking spiders.

It should be noted that the manufacture of spider silk is not easy and there are intrinsic difficulties. First of all, spiders cannot be cultivated like silkworms since they are flesh-eaters and will merely eat each other if in proximity to each other. The silk produced is very slight, so 400 spiders would be required to make only one square yard of cloth. The other problem is, silk also toughens when subjected to air, which makes working with it problematic.

A different tactic is to study how spiders whirl silk and then replicate this process to make artificial spider silk. The silk itself would also have to be synthetically produced. Chemical production of spider silk is not feasible at present due to the absence of information about the makeup of silk. Randolph V. Lewis, Professor of Molecular Biology at the University of Wyoming in Laramie, has introduced silk genes into Escherichia coli bacteria so that the recurring sections of spidroin 1 and spidroin 2 efficaciously come to form. Others theorize about the likely gene introduction into fungi and soya plants. It may also be possible to modify the silk genes for precise intentions.

Why a spider’s house is the frailest of houses

Spider silk is stronger than steel, but the Qur’an (29:41) states that the flimsiest of houses is the spider’s house. The per unit weight of the dragline silk of the golden orb spider is one of the world’s hardest fibers. Webs are combinations of many kinds of spider silk, all able to be produced by the same spider. The web radials are strong, but the somewhat feebler circumferential (quasi-circular concentric) fibers are flexible and gluey to absorb the energy of a flying insect and hold it in place. The strongest of all is the fiber, which the spider uses for transport, the dragline silk. In summary, the spider fabricates both sturdy as well as feeble fibers and the web it weaves to catch flying insects is weaker; this may be the reason why it is referred to in the Qur’an as the “frailest” of houses.

Conclusions

Scientists are foreseeing many potential uses for biosilk. Textile usages are noticeable one. The flexibility and potency of prevailing merchandises such as spandex and nylon have to be improved. Since it is lightweight, hardy and flexible, biosilk may also have uses in satellites and aircraft. More prominently, the new group of progressive things that spider silk investigation may cause has the prospective to alter our lives in innumerable manners that we can barely imagine. More than 72 years have passed since the inventions of Wallace and Carothers that gave the world nylon that led us into the age of polymers. Artificial spider silk may help produce super-performing clothes of the future. Earthquake resistant suspension bridges hung from cables of synthetic spider silk fibers may someday be a reality. [1]

References

1. Syed, I. B. : Spider Silks http://www.irfi.org/articles/articles_1_50/spider_silks.htm
2. Romer, L and Scheibel, T.: The elaborate Structure of spider silk, PRION, Oct-Dec. 2(4) 154-161, 2008. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2658765/
3. RIKEN Center for Sustainable Resource Science (CSRS). Scientists discover key mechanism behind the formation of spider silk. Materials Science. May 29, 2018, https://phys.org/news/2018-05-scientists-key-mechanism-formation-spider.html

4. Nur Alia Oktaviani, Akimasa Matsugami, Ali D. Malay, Fumiaki Hayashi, David L. Kaplan, Keiji Numata, “Conformation and dynamics of soluble repetitive domain elucidates the initial β-sheet formation of spider silk”, Nature Communications, 10.1038/s41467-018-04570-5 https://en.wikipedia.org/wiki/Riken
5. Service, Robert F. (18 October 2017). “Spinning spider silk into startup gold”. Science Magazine, American Association for the Advancement of Science. Retrieved 26 November 2017. https://en.wikipedia.org/wiki/Spider_silk
6. Vivienne Li, University of Bristol, Spider Silk and Venom. Molecule of the Month – July 2002. http://www.chm.bris.ac.uk/motm/spider/page4.htm

Global Climate Report. NOAA National Centers for Environmental Information (http://www.ncdc.noaa.gov). July 2019.

It’s summer, and it is hot out there; but if it feels like record-breaking temperatures are becoming more common globally, they are. The National Oceanic and Atmospheric Administration and European Copernicus Climate Change Service announced that July 2019 was the hottest month across the globe ever measured since measurements began, in 1880. Global temperatures averaged 16.73°C in July, which is 0.95 °C higher than the 20th-century average of 15.78°C . Average Antarctic sea-ice coverage was 8.5% below the 1981-2010 average. And sea ice coverage was 10.5% below the overall average, which is based on records beginning in 1979. The scientists also released geographical data, showing that the regions where temperatures varied furthest from averages, were Alaska, Central Europe, Northern and Southwestern parts of Asia, and certain regions in Africa and Australia. These findings corroborate scientific predictions regarding the effects of man-made climate change. Human activities, primarily from burning fossil fuels, emit carbon dioxide and other greenhouse gases that trap heat in the atmosphere. Increasing greenhouse gas emissions are associated with warmer global surface temperatures. The planet’s 10 hottest years on record have all fallen in the past two decades. Scientists and policymakers around the globe are also feeling this heat.

Unless significant measures to curb greenhouse gas emissions are adopted, scientists expect temperature records to keep falling. Scientists say global temperatures could increase by at least 3°C this century, which will create conditions on Earth that have not been seen in more than 2 million years. Given the notable trends in higher temperatures and natural disasters, we might be pushing the climate system toward states that we haven’t seen in our societal experience – and even in our species’ experience.

Manipulation of brain circuits using smartphone-controlled device

Qazi R et al. Wireless optofluidic brain probes for chronic neuropharmacology and photostimulation. Nature Biomedical Engineering, August 2019.

Scientists recently designed a device that can regulate brain circuits using a tiny brain implant controlled by a smartphone. This bluetooth-enabled device utilizes replaceable lego-like drug cartridges to target neurons with drugs and light. Existing methods to deliver drugs and light to the brain typically involve metal tubes and optical fibers. These tools are rigid and can substantially damage the brain’s soft tissue over time. Moreover, this bulky equipment often limits the patient’s movement because of the wired connections, making them unfit for long-term use. To achieve chronic remote-controlled drug delivery without exhaustion and evaporation of drugs, scientists invented a neural device with a replaceable drug cartridge, which could allow neuroscientists to study the same brain networks for several months without depleting the drug supply. These “plug-n-play” drug cartridges were integrated into a brain implant for mice with a soft and ultrathin probe (about the thickness of a human hair), which consisted of microfluidic channels and tiny LEDs (smaller than a grain of salt), for unlimited drug doses and light delivery. The implant is regulated via a smartphone, allowing researchers to trigger precise combinations and sequences of drug and light delivery. In animal models, these stimuli can be triggered with the target outside of the laboratory, allowing researchers to wirelessly instill changes in the animal’s brain while in its natural habitat. Using these neural devices, researchers are now able to perform fully automated animal studies where the behavior of one animal could positively or negatively affect behavior in other animals by conditional triggering of light and/or drug delivery. This device will allow researchers to better dissect the neural circuit basis of behavior and how specific neuromodulators in the brain tune behavior in various ways. In addition, the device can be utilized in complex pharmacological studies to develop potentially new therapeutics for pain, addiction, and emotional disorders.

The secret weapon of E.Coli 

Melson E. at al. The sRNA DicF integrates oxygen sensing to enhance enterohemorrhagic Escherichia colivirulence via distinctive RNA control mechanisms. Proceedings of the National Academy of Sciences, June 2019.

Scientists have revealed how E. coli (Escherichia coli) bacteria seeks out the most oxygen-free parts of your colon to cause the worst infection possible. E. coli normally live in the intestines of healthy people and animals. Most varieties of E. coli are harmless or cause relatively brief diarrhea. But a few particularly nasty strains can cause cramps, diarrhea, vomiting – even kidney failure and death. Children are particularly at risk. A new study uncovers how this foodborne pathogen knows where and when to begin colonizing the colon on its way to making you sick. Bacterial pathogens typically colonize a specific tissue or organ in the host. Therefore, as part of their infection strategies, bacterial pathogens precisely time deployment of proteins and toxins to these specific colonization niches in the human host. This allows the pathogens to save energy and avoid detection by our immune systems and ultimately cause disease. The researchers in this study identified how E.Coli detects low oxygen levels in the large intestine and then produces proteins that allow it to attach to host cells and establish infection. Oxygen actually diffuses from the intestinal tissue into the gut, and there are comparably higher levels in the small intestine than the large. Remarkably, E. coli specifically waits until it has reached the-low oxygen large intestine before striking. E. coli controls this process via a small form of RNA that activates particular genes when oxygen levels are low. This is the point when the infection really gets established and the bacteria are able to begin to manufacture harmful Shiga toxins. The researchers predict that other bacterial pathogens, such as Shigella and Salmonella, likely utilize a similar control mechanism. Researchers suggest that if we can find a way to block oxygen sensing, we may be able to prevent the infection by allowing E. coli to pass harmlessly through the body.

Artificial photosynthesis transforms CO₂ into liquefiable fuels

Yu and Jain. Plasmonic photosynthesis of C1–C3 hydrocarbons from carbon dioxide assisted by an ionic liquid. Nature Communications, May 2019.

Scientists have recently established a reliable “artificial photosynthesis” paradigm to produce fuels from water, carbon dioxide, and visible light. With the help of sunlight, chemical reactions between water and CO₂ are catalyzed in plants to generate and store solar energy in the form of glucose. This process is called photosynthesis. In the new study, the researchers developed an artificial process that uses the same mechanisms of natural photosynthesis to convert CO₂ and water into liquid fuel by using electron-rich gold nanoparticles as a catalyst. Gold nanoparticles function in the same role as chlorophyll in natural photosynthesis in the absorbing of light and transferring electrons and protons to catalyze the chemical reactions between CO₂ and water. They are known to be efficient at absorbing light and do not break down or degrade like other metals. The energy stored in the bonds of the hydrocarbon fuel can be freed by the conventional method of combustion or by new-generation, environmentally-friendly power fuel cells, thus producing electrical current. By converting CO₂ into more complex molecules like propane, green-energy technology is now one step closer to using excess CO₂ to store solar energy for use when the sun is not shining and in times of peak demand. While the development of this CO₂-to-liquid fuel may be exciting for proponents of green-energy technology, the artificial photosynthesis process is nowhere near as efficient as it is in plants. New methods should be developed to increase the efficiency of the catalysts and downstream chemical reactions at much higher scales.

Brain area that watches for walls identified

Henriksson et al. Rapid Invariant Encoding of Scene Layout in Human OPA. Neuron, May 2019.

Neuroscientists have identified the part of the human brain whose duty is to help us perceive the barriers which define the navigable space around us, such as walls or ceilings, so that so we can avoid bumping into things and navigate safely through our environment. By way of vision we have an almost instant sense of where we are in space. Although this process feels effortless, it requires the coordinated activity of multiple brain regions and neurons working together to give us this sense of our surroundings. This process has remained unknown. But thanks to a new study, we are a step closer to solving the puzzle. Using cutting-edge brain-imaging technologies, researchers examined the mental responses of volunteers as they were shown images of various three-dimensional scenes. The images depicted a typical room with three walls, a ceiling, and a floor, but then were abruptly changed by the removal of a wall or a ceiling. By doing this repeatedly, the team could pinpoint how the participant’s brain encoded every scene. In the brain scans of the volunteers, one brain area called the occipital place area (OPA) clearly stood out. OPA activity represented the geometry of the scenes and activity patterns, reflected the presence or absence of each component, such as a ceiling or a wall, and projected a detailed picture of the overall configuration. Interestingly, OPA seemed to ignore the surface appearance of the various components such as colors or textures in order to focus only on the geometric patterns. The OPA managed to perform all the necessary computations needed to get a sense of a room’s layout extremely fast – in just 100 milliseconds. In the future, the research team plans to incorporate virtual reality technology to create more realistic 3D environments for participants to experience, hopefully achieving much deeper insights into how our brains process and makes sense of the visual information.

Gut segments are organized by function

Esterházy D. et al. Compartmentalized gut lymph node drainage dictates adaptive immune responses. Nature, April 2019.

As food enters our intestine, it goes through a windy and lengthy journey. A new study provides new insights into how our intestines maximize nutrient uptake while protecting the body from potentially dangerous invading microbes. At first glance, the intestines appear to have a uniform tissue structure. But when scientists looked at them closer, they found that our food-processing canal seems to consist of multiple compartments that pace the immune system’s reactions to the food passing through. Scientists uncovered these functional intestine segments in mice when they examined the intestinal structures called gut draining lymph nodes, which orchestrate immune responses. The researchers found that nodes in different parts of the intestines had different cell composition, and they saw different immune responses between segments when they challenged the mice with a pathogen. They observed less aggressive defenses in the first segments where nutrients are absorbed, and more forceful responses at the end, where pathogens are eliminated. Researchers plan to exploit these immunological differences between the gut segments for treating gastrointestinal disorders. For example, by targeting immune-suppressing drugs to the specific gut segment where they’ll have the most effect, it might be possible to dampen their side-effects. The spectrum of immune responses along the intestines could also be used to make new and better oral vaccines. Thus far, scientists’ efforts to design oral vaccines have been hampered by the difficulty of generating a robust immune response; it is possible that the muted immune response at the beginning of the intestines might be part of the reason why oral vaccines tend to be less effective than injections. Thus, targeting the distant end of the intestine might be much more efficient way of inducing the immune response required.

We live in a magnificent world inhabited by approximately 8,700,000 species. This number includes only general species, not subspecies. Scientists discover around 2,500 new species every year, and the number is soon estimated to reach 10 million.

All living organisms are blessed with unique bodies, systems, and organs, defense and protection mechanisms to survive and protect themselves, and special features to help them forage for food.

When people get ill due to environmental effects or malnutrition they usually consult a doctor. They try to find a cure by using the medicine prescribed by doctors. However, animals living in the wild don’t have this option. When animals living in nature or on the street get ill what can they do if nobody takes them to a vet? How do millions of species get well and find cures for their ailments?

You might think that animals who become sick in the wild must simply live with their symptoms, but this is not the case. In fact, we have given a clue at the introduction: each organism is equipped with features to lead a self-sustaining life. Either their bodily functions perfectly enable them to live in their habitat or their unique metabolisms protect them from harmful external factors. Animals also can use some plants whose health benefits have only recently been discovered by humans.

In recent decades, there has been a growing interest for herbal products such as walnut leaf, cherry stalk tangerine rind, grenadine red, and celery root to find cure for diseases.

Animals perform amazing tasks with mind-blowing adroitness as if each were an expert chemist. Wondrous mechanisms are activated when a need arises to protect animals from harm.

Some plants with healing properties:

Lupine, quassia, bitter wood, hemlock, fishberry, roselle, henbane, giant fennel root, pistachio, resin, pine turpentine, mistletoe, cumin, hibiscus, hibiscus flower, alkanet, flos elaeagni, camphor, cardamom, St John’s wort, French lavender, Flaxseed, linseed oil, henna tree, quillaia, wall germander, cranberry, aspand, daffodil, water lily, common balm and eucalyptus.

Animals have been consuming and finding cures in these plants since the dawn of time. They are also equipped with many surviving capabilities under extremely severe conditions. Here are a few examples:

Antibiotics expert

With a height of up to five meters, the giraffe is the tallest land animal. Scientists who investigated the scent emitted by the giraffe found 11 separate chemical substances in its fur. The chemicals turned out to have antibiotic properties, having an increased efficiency when combined. Only after a series of experiments can these incredibly complex chemicals be extracted in the laboratory. The giraffe has been using these chemicals to prevent fungi and bacteria, repel ticks, and stop the growth of germs. Where did these tall creatures study chemistry to know how to produce antibiotics such as indole?

The stubborn doctor

The bezoar ibex is a type of mountain goat native to Turkey, Iran, Turkmenistan and Pakistan. It has a motley coat of black, brown, grey, reddish-gold, and white. Both the male and female have horns and a goatee. The name means “cure” in Persian, and the locals must have noticed its habit of eating spurge whenever bitten by a snake. Scientists have identified the substance called euphorbone in the spurge plant. Amazingly, an analysis of this substance reveals that certain chemical reactions triggered by euphorbone neutralize the effects of venom. The poisoned creature looks for splurge from among the vegetation, self-medicates, and treats itself free of charge. It sure is no wonder when one realizes that the goat, the snake, and the plant are all created by the same hand.

The master of diving

Divers who ascend too quickly to the surface run the high risk of experiencing the bends, an intense pain that is likely to kill because of the gasses coming out of the bloodstream. But how do billions of creatures that lack oxygen tubes lead their entire lives in the sea without experiencing the bends?

Dolphins and whales, for example, descend to depths humans can’t reach on their own and then rise like it is no big deal. Human lungs cannot endure the pressure under such depths, but the bronchi and air sacs in the lungs of dolphins, however, are placed inside a protective cover of special cartilage. To avoid suffering the bends, dolphins release all the air in their lungs before diving deep. But how then do they breathe? The answer is hidden in their muscles, or rather in the myoglobin protein that is available in much higher amounts than in humans. These proteins have the ability to hold in high amounts of oxygen molecules. The much needed oxygen is provided from this source, enabling dolphins and whales to dive as deep as possible.

Poison for one, food for another

The macaw is an inhabitant of American tropical regions with an average wing span of 80 cm. It is known to be a tough creature that lives as long as 60 years. The macaw feeds on plants that produce a chemical called strychnine (C₂₁H₂₂N₂O₂), a powerful poison intended to ward off enemies. How can a substance that kills some living things nourish others? Immediately after eating the nutritious but poisonous seeds, the macaw flies to the rocky cliffs in a certain area. When they get there, they gnaw at and swallow some clay-based rock pieces. The fact that the bird ingests clay without any apparent reason is quite an interesting behavior. The reason was revealed only after research into the origins of the behavior. It turns out that the rocks that have clay in them include a substance called kaolinite (Al₂O₃.2SiO₂.2H₂O) that can absorb the poison in the seeds. The macaw can digest the normally poisonous seeds thanks to this absorption and live on with its life safely. There is no way the macaw can know about the substances present in the clay, so how does it know to eat the clay that can eliminate toxins?

The antifreeze expert

The arctic beetle survives against the inhospitable cold of the arctic thanks to a type of alcohol produced in its body that works as antifreeze. The glycerol (C₃H₈O₃), also called glycerin, produced by the insect prevents the blood and other fluid molecules from freezing and thus ice crystals from killing the cells and destroying cellular bonds. Furthermore, the shorter the days and the colder the weather, the more resistant the bodily mechanisms of the arctic beetle become. As the temperature drops, the volume of water in their body is reduced and antifreeze substances such as glycerol and sorbitol are produced in greater amounts. Research on this amazing creature has revealed that it can survive in temperatures as low as -87 degrees Celsius due to glycerol. It is beyond reason to expect an insect to know how to produce an organic compound with the complex formula of C₃H₈O₃ and thus protect itself from extreme cold.

The radiation expert

Scientists analyzed a surviving scorpion after an atomic bomb test, yet they couldn’t find a satisfying answer to how this animal survived the radiation shower that exterminated all other living organisms. Note that scorpions which came into existence millions of years ago are basically living fossils. Thanks to the protective system they are blessed with, in the past they have survived more powerful solar explosions and harmful radiation from outer space and the sun, and handed down these features to future generations.

The creature that never feels cold

The tardigrade, or water bear, is one of the most resistant organisms in nature.

The size of a pinhead, these microorganisms have pin-shaped hoses in their mouth.  These microorganisms have a brain, a pair of eyes, and a digestion system, but they do not have a heart or lungs.  600 different subspecies of the animal have been discovered so far. They feed mostly on moss and lichens and can survive in any environment including space.

They have been observed to survive a temperature of 120 ⁰C and a pressure of 1000 atm. In dry environments they contract, causing the water in their tissues to evaporate. During this process, the oxygen consumption of the tardigrade virtually stops. The wind carries the dried tardigrades to other places and when they find a suitable environment (wet moss or humid places) they can come back to life again.

According to Ingemar Jönsson from Kristianstadt University in Sweden who participated in studies on this organism, it is a mystery how these animals survive even when they are subjected to conditions in outer space.

Animals perform amazing tasks with mind-blowing adroitness as if each were an expert chemist. Wondrous mechanisms are activated when a need arises to protect animals from harm. It is wondrous to see how animals can carry out these complex chemical procedures as if they have been instructed at birth.

Agrochemical control of plant water use via engineered abscisic acid receptors
Park et al. Nature, February 2015.

A recent breakthrough study reported that scientists successfully engineered drought-tolerant plants by adding a new piece of DNA to their genomes. Crops and many types of plants are increasingly challenged by hostile environmental conditions such as globally warming temperatures and diminishing water sources. Plants have very small openings called “stomata” that let carbon dioxide in and oxygen out. Each stoma is surrounded by two guard cells that control opening and closing using osmotic pressure. During daytime, the stomata lets plants allow carbon dioxide in and oxygen out. Since the air around the leaves is often drier than inside, water molecules also move out through the stomata – a process called transpiration. Under the stress of drought, plants produce a hormone called abscisic acid (ABA). When ABA is released, it makes guard cells close the stomata and in turn keeps the plant from losing the water. Scientists previously thought that if they could spray ABA on a whole field, plants would survive a drought. However, since ABA is very expensive and highly sensitive to light, this strategy never became an option. Then, scientists decided to take the commonly used fungicide mandipropamid and genetically engineered the plants to respond to mandipropamid as if it were ABA. By adding a new piece of DNA into genomes, plants ended up having slightly different ABA receptors, which can be efficiently activated by mandipropamid.  Researchers tried this approach on two different plants: tomatoes and Arabidopsis. When mandipropamid was sprayed, genetically engineered plants stopped transpiration, and hence were able to survive for 12 days without water. The next challenge is to test this strategy in real world crops. This approach potentially opens new avenues for crop improvement that could highly benefit a growing world population.

3D Vaccines to Cure the Cancer

Injectable, spontaneously assembling, inorganic scaffolds modulate immune cells in vivo and increase vaccine efficacy
Kim J et al. Nature Biotechnology, December 2014.

Cancer is a devastating disease.  The World Health Organization (WHO) predicts that global cancer incidence rates will grow by nearly 60% to 22 million cases per year over the next two decades. The effective cure for cancer has not been developed yet, mostly due to its ability to escape the body’s immune system. Unlike infectious reagents like bacteria and viruses, cancer cells are actually our own cells that are broken and misplaced; they cause trouble as they grow. Scientists have been trying hard to develop vaccines that activate the immune system to recognize tumor cells as foreign and attack them. In a recent study, scientists reported that they designed a “3D vaccine” to effectively provoke the immune system to fight cancer. The 3D vaccine is composed of many microsized, porous silica rods submersed in liquid, where any combination of tumor antigens and immune-stimulating reagents can be loaded into.  Once the 3D vaccine is injected under the skin, it forms into a dime-sized scaffold that creates an “infection-mimicking microenvironment.” The scaffold then attracts the dendritic cells that patrol the body for harmful pathogens. When the scaffold was tested in mice, it showed over a 90% survival rate in animals that would normally die from lymphoma within 25 days. Further analyses in mice showed that the 3D vaccine can recruit, house, and manipulate immune cells to initiate a powerful immune response against cancer. As much as the discovery is promising, one should keep in mind that much more evidence will be required to establish 3D vaccines as a feasible way of combating human cancer.

Smoking Shrinks the Brain

Cigarette smoking and thinning of the brain’s cortex
Karama S et al. Molecular Psychiatry, February 2015.

Smoking is regarded as the single most preventable cause of disease, disability, and death. Past studies strongly linked smoking to cancer and lung diseases. A recent study now shows that smokers have a thinner brain cortex than non-smokers. The cortex is the outer brain layer in which critical cognitive functions such as memory, language, and perception take place. It is well known that the cortex becomes thinner with normal aging and cortical thinning is associated with cognitive decline and dementia. The study found that smoking accelerates this thinning process. Researchers analyzed brain MRI scans of 244 males and 260 females with an average age of 73, around half of whom were former or current smokers. Participants who had given up smoking for the longest time had a thicker cortex compared with those who had given up recently. Researchers cautiously suggest that the cortex might regain some thickness once smokers quit but the recovery is very slow and incomplete. For example, heavy smokers who had quit more than 25 years before still had a thinner cortex.