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christina koch nick hague

Female NASA astronaut to make new record by spending extended time in spaceflight

NASA announced that astronaut Christina Koch will break a space record of the longest continuous spaceflight by a woman which is currently held by astronaut Peggy Whitson. As of now, she holds the record with 288 days but Koch who went to the space with Nick Hague and Alexey Ovchinin will be staying in the orbit for 328 days. She will return back to Earth in the month of February 2020. Though she will not be breaking the record set by astronaut Scot Kelly of the longest continuous spaceflight at 340 days.

Doctors are quite excited by this announcement as they will be able to learn a lot from it. During her time in space, Koch will monitor the changes taking place in body. It will provide researchers with the much needed valuable data of dangers of spaceflight and how well can human bodies cope with it. This data has been quite difficult to obtain as space flights usually last for six and a half months, but only few astronauts have been able to stay more than 200 days in one spaceflight. This situation presents a problem to NASA, as they aspire to send human beings to Mars within a decade, which is spaceflight lasting for six to eight months in each direction. Koch’s journey in the orbit of Earth will be able to inform us of the hardships of such long spaceflights and how differently male and female bodies react to the changes.

It is significant to note that till date, only three NASA astronauts have been able to remain in space for a continuous 200 days. They are Scott Kelly who holds the record at 340 days, Peggy Whitson, 289 days and Michael Lopez-Alegria at 215 days. It is interesting to note that Soviet Union and Russia combined have sent a dozen men on spaceflights for more than 200 days.

About 12% of the astronauts on spaceflights have been women, hence this mission will provide a more profound understanding of how gender differences affect the response of the body. A coincidence is that this updated flight schedule was announced just a week after the Twin Study was published. This revealed how cells of genetically identical individuals differed in responses, when one brother was in spaceflight and the other on Earth.

Koch will be taking part in several projects such as VECTION for studying how the vestibular system processes the movements of individuals in gravity. Besides this, there will also be experiments checking the stiffness of muscles, elasticity, ability of the brain in controlling blood flow.

Scientists want large sample size of astronauts for spaceflight studies, but since it is not possible they want to utilize the data from every individual who makes long stays.

soft total artifical heart

For the first time scientists successfully create a complete heart by 3D printing

A team of researchers at the Tel Aviv University has managed to successfully 3D print a small heart by using human tissues which includes blood vessels, biological molecules and collagens. This is considered to be a remarkable achievement as the scientists hope that with the help of this, they can make organ donation to be a thing of the past.

This achievement was reported by head researchers from TAU’s Faculty of Life Sciences, Professor Tal Dvir, Dr. Assaf Shapira and his doctoral student Nadav Noor in the Advanced Science journal.

The 3D printed heart is the size of a rabbit’s and it is not fully functional yet. However, the team has pointed out that the technology involved in 3D printing the heart for a human body is essentially the same. There are several steps of improvement left in the heart as the cells need to possess the pumping ability, a crucial working of the heart. Currently, the group of cells can contract but they need to work together. The scientists believe that they can succeed in increasing the efficiency of the method.

So the next step in the line is to make the printed heart grow and mature in the laboratory and make it learn how to function like an actual heart. Only after then can scientists take the decision to use it for transplant in animals for testing their functionality. This is a very time-consuming process and it may take years before this technology can create actual functioning organs that are ready to transplant. Nevertheless, this is a significant progress, as three-dimensional printing has managed to print tissues but not the blood vessels, which is very important for its working.

Dr. Dvir said that this is the first time, a team has successfully managed to engineer and print an entire heart with all the components inside it, the cells, blood vessels, chambers.

Scientists have previously printed cartilage and aortal tissues, but the main challenge was not accomplished, which is to create tissues with complete vascularization, blood vessels, capillaries. In the absence of these, the organs would not survive.

The scientists began the process with fatty tissues extracted from the human body and then they separated the cellular components from the non-cellular components. After that, they programmed these cells to undifferentiated stem cells which can be nudged to form cardiac cells or endothelial cells. The non-cellular materials such as the proteins galore were processed to form a personalized hydrogel which served as printing ink.

Organ printing basically involves three stages. The first stage is called the pre-print stage, which involves scanning the organ. The second stage is printing the organ and the third stage is maturing the organ in a proper environment.

Callao Cave Philippines

Researchers discover fossils in Calleo Cave indicating a new hominid species

Scientists have reported the discovery of an unknown species of human beings who resided in the Philippines almost 50,000 years before. The recently found evidence shows that new species, Homo luzonensis was very small in size and maybe even smaller than the Hobbit species which was discovered in the Flores island back in 2004.

This discovery has made the timeline of human evolution very messy but nonetheless fascinating due to the discovery of the species which was previously not known. Small pieces of bones and teeth were found from the Callao Cave in the Philippines island of Luzon. The fossils found in the Callao Cave give clues of many features which have been totally unknown to the researchers. Hence it makes the statement for the declaration of a new human species, Homo luzonensis. This discovery was reported in the Nature journal.

This is a breakthrough discovery as it is not regular to find about new human species. The discovery of Homo luzonensis can reveal facts about human evolution and what happened to the ones who left Africa thousands of years before.

In 2010, a single human foot bone was discovered in Calleo Cave which was dated at 67000 years old. This was the first evidence that humans have been present in Philippines for quite some time. We have known that hominins, the group of primates who are more closely related to us than chimpanzees lived in Philippines as early as 700,000 years ago.

The hominins are not exactly our direct ancestors but they can be considered as close relatives. Each species had their own evolutionary journey as they adapted to changing environments and circumstances. Around 50,000 years ago in Africa, there were many human species in Africa and Eurasia.

The team of scientists led by Florent Détroit, National Museum of Natural History located in France and Armand Mijares, University of the Philippines who found the foot bone in Philippines have tried to gather more evidence around Calleo Cave. The excavations have led to the discovery of 12 hominin elements in all which includes a thigh bone, and several bones of hands and feet. Scientists have identified them belonging to two adults and one child. Unfortunately, there was no genetic evidence present in these specimens.

Analysis of the specimens gives rise to the conclusion that the species, Homo Luzonensis have been very small compared to the present size of human beings. Scientists suspect that they may have been subjected to insular dwarfism, a condition where the size of a species gets significantly reduced due to very less to the resources needed for development.

Although some of the scientists feel it is too soon to declare the luzonensis a new species and that only another set of fossils complemented by DNA and mark them as a new Homo member.

Toxoplasma gondii

A chlorophyll containing microorganism found which does not photosynthesize

Researchers have been able to find an organism for the first time which can create chlorophyll but still does not participate in photosynthesis. This organism is named as ‘corallicolid‘ as it is found in almost 70 percent of the corals all over the world. This finding can provide clues on how to protect the ‘coral reefs’ in future.

Patrick Keeling, a researcher and botanist at the University of British Columbia said that this organism is the second most frequent cohabitant of coral in Earth but it has not been observed till now. It gives rise to several different questions related to biochemistry. A very unusual fact is that it produces chlorophyll but it is not photosynthetic at all.

Chlorophyll is a green pigment which has been found in the plants, cyanobacteria and algae and it is responsible for capturing energy from the sunlight during photosynthesis. They absorb the maximum amount of light in the blue and red regions of the electromagnetic spectrum. On the other hand, it is a poor absorber of the green and the regions in the spectrum closer to the green, because of which it is reflected in the form of green colours in tissues containing chlorophyll. It is of two types in plants, chlorophyll a and chlorophyll b. 

In the photosynthetic process, chlorophyll in range of several hundred molecules per photosystem absorbs light and then it transfers the light energy to a very specific chlorophyll pair in the reaction centre in the way of resonance energy. Now for corallicolids, it is quite dangerous to have chlorophylls in the cells but not performing photosynthesis in any manner as the energy which has been absorbed is not released and thus it is like a trapped explosive in the cells.

These organisms reside in the cavity of a wide range of corals that are responsible for constructing coral reefs, black and fan corals, mushroom corals and anemones. They belong to the vast group of parasites which have a cellular region called plastid and are called apicomplexans. Malaria causing parasite is a big example of an apicomplexan.

The ecological information reveals that although the coral reefs contain many apicomplexans, the most recently discovered corallicolids have been not noticed until now. The most puzzling thing is that it not only possesses plastid but also the four plastid genes used in chlorophyll production, yet does not participate in photosynthesis.

Researchers hope future research on these organisms will allow us to reveal the mystery behind them and also preserve them in a better way.

Bacteria 3D Double Helix

Scientists able to create an entire genome set using programming algorithms

A team of researchers from ETH Zurich has reported about the creation of a bacterial genome entirely with the help of a computer algorithm. This report was published in the Proceedings of the National Academy of Sciences. The genome is named as Caulobacter ethensis-2.0. Although it is not yet a living microorganism it exists as a DNA bundle.

This new genome was created from the naturally occurring bacteria, Caulobacter Crescentus. It is usually found in spring waters, rivers, and several lakes. It is inherently harmless and thus used as a model creature in the laboratories. The bacteria’s genome has 4000 genes, but most of them are considered as “junk DNA” and around 680 are considered as essential to support its survival.

Apart from this, the gene set also contains several redundancies as many combinations of the amino acids and proteins which are assembled by the DNA often give the same result. As a result of this scientists created a program to find out the ideal DNA combination. The algorithm was able to fully rewrite the genome as a different DNA sequence which did not resemble the original one at all but was still able to perform the biological functions.

This research work is built on the work of Craig Venter, pioneer of American genetics. He was the first person to chemically synthesize the bacterial genome. This work took almost a decade to finish. The main difference between the work of Venter and the genome created by the algorithm is that the latest one contains a totally new set of genes whereas the former one was an exact copy.

Creating an entire set of bacteria genome totally from the beginning is a very complicated task to achieve. It requires very accurate calculations. The team started with a minimal gene set of the Caulobacter, and it created 236 genome segments from it. After this, the segments were tied together. This sounds like an easy task but it is very difficult to execute. It is very challenging as the DNA molecules can easily get stuck to each other and become twisted and messed up.

The natural world has inbuilt genetic redundancies because of which multiple genes can encode for a single protein. Because of this, the researchers used to rewrite the genome using absolutely unrelated genetic sequences and it still provided the same biological functions.

For testing the genome set, the team created several strains of bacteria using both the natural Caulobacter and the segments of the artificially created genome. When they removed the natural genes, it was found that 580 of the genes were still functional. Hence there is still some room for improvement before a fully functional artificial genome is produced.

Mark and Scott Kelly at the Johnson Space Center

NASA’s Twin Study reports changes in human body during spaceflight

Spending a year on the space station has a great impact on the human body but the normal body functions get restored after returning to Earth. Human beings were not evolved to be able to float in microgravity or to survive under the influence of radiation levels in space.

NASA astronaut, Scott Kelly spent almost an year on International Space Station in a mission launched in 2015. His body was subjected to incredible stress, accumulation of fluids in upper body and head led to the swelling of these parts, his genes were activated in unusual ways and his immune system went to overdrive compared to his identical twin brother, Mark Kelly. Both the brothers have been in space, but Mark remained on Earth during Scott’s mission. As time passed, Scott experienced reduced body mass, genome instability, major swelling in his blood vessels, shifts in metabolism and changes in his microbiome and also a increase in the length of telomeres.

A group of ten teams were working on NASA‘s Twin Study which included 84 researchers from 12 universities. They followed the brother duo, during and after the flight got over and tracked the change in the bodies of the brothers over the entire course of the study. Though the scope of the research was limited, this data will be very valuable when scientists plan to send astronauts on long duration spaceflights.

Because of the small sample size, there was no interest in the Twins’ Study for many years after both of them got selected as astronauts in 1996. But after Scott Kelly’s record breaking stay in space station, the discussion gathered steam and a proper study was undertaken whose full report will be soon published. Mike Snyder, the head of genetics at Stanford University and a co-author of the Twins’ Study said that this will be the first in-depth study of the people in space at a biochemical level.

A lot of interesting changes have been noticed in the twins’ genes. There are no changes in the DNA, but there have been changes in the genes which are activated to synthesize proteins. Researchers did not compare the genes of the brothers directly but rather compared the changes in the genes’ expression. As soon as Scott went into space, there was a huge shift in the over 1000 genes which change dynamically. This shows the response of the body to a completely different environment.

The most curious finding was that of the lengthening of telomeres. Telomeres are the chromosome ends which shorten as we get older. Although the telomeres returned to the same average length on his return to Earth.

The integrated report from the Twins Study researchers was released in the Science journal.

Sperm whales off Mauritius coast

Discovery of four legged whale ancestors is an evolutionary missing link

A research published in the Current Biology, reveals the discovery of a new species of ancestral whale that walked the land and sea in Peru. We may consider them as smooth, two-limbed marine mammals that even struggled to survive the Thames, but the whales originated more than 50 million years ago from land-dwelling, hooved mammals called artiodactyls. The ancestors of the whales resembled a small deer. A fossilised “missing link” discovered in India claimed that the last whale precursors took to the water when danger dawned upon them but would come onto land for reproduction and feeding.

They would generally spend a considerable amount of time slopping in shallow water, quenching for aquatic vegetation and invertebrates.

The oldest whale fossils date back 53 million years ago and were found at numerous sites located in the northern Indian Himalayas. The fossils talk of the gradual transition from simple slopping to life long living in deeper water, while retaining the ability of locomotion on land.

42 million years ago, the freshly discovered Peregocetus pacificus started an epic journey to the other side of the world. In the Middle Eocene era (roughly 48 to 38 million years ago) when Africa and South America were far apart these animals who were smaller than 3m swam their way across, not used to marine life back then.

The hind limbs were not as small as its forelimbs, and it had really tiny hooves, suggesting that it was still quite capable of hoisting itself out of the water and then trotting about on land, that is capable of getting out of water and walking on land. However, the skeleton suggested that it was well adapted to an aquatic life that was about to become dominant. It was carnivorous, as demonstrated by its scissors- like teeth. It ate large bony fish, just as the whales do now. However, P. Pacificus had teeth which resembled that of the modern carnivores.

By using microfossils, the sediment layers where the skeleton was claimed to be positioned were precisely dated and then the details of the skeleton allowed them to conclude that the animal was capable of carrying its body both on land and in the water. However, over the millennia, their pelvic bones unattached themselves from the spine to enable more efficient swimming while increasing the time in buoyant, the gravity-easing water reduced the evolutionary resources to strong, weight-bearing legs that they possessed. Forelimbs morphed into flippers, while hind limbs shrunk and disappeared.

Representation of dna body strand

Researchers find evidence of DNA and RNA even before life on Earth

Scientists have found a piece of strong evidence that both DNA and RNA might have been formed from the same precursor molecules even before the evolution of life on Earth. The research published in Nature Chemistry shows that the first living beings on our planet might have had both RNA and DNA like all other cellular-based life forms. This is in contrast to the current understanding that the earliest life forms only possessed RNA and DNA was formed with the evolution of life. This is commonly known as the RNA World Hypothesis. After this new finding, scientists should not fully rely on the RNA World Hypothesis for carrying out investigations on the origin of life on Earth.

RNA and DNA are chemically quite similar but chemists have not been able to show how one could have been converted to the other in earliest stages of our planet without the help of enzymes which are produced by the organisms. Because of this reason, researchers have always concluded that RNA is the basic component of the earliest life forms. RNA can store genetic information like DNA and also store catalyse biochemical reactions like protein enzymes. Hence it could have performed the basic biological functions in the earliest forms of life.

Ramanarayanan Krishnamurthy, a chemistry professor at Scripps Research along with his colleagues found a compound which was present in pre-biotic Earth and performed the essential task of linking RNA blocks to larger RNA strands and could have done the same for proteins and DNA.

Scientists have identified a compound named thiouridine which was likely to be present on Earth before the formation of life and it could have been a chemical precursor to the nucleoside blocks of the early RNA. It was found that by means of few chemical reactions this compound could be transformed to deoxyadenosine, a basic building block of DNA. They could also convert thiouridine to deoxyribose which is very closely related to deoxyadenosine.

These findings are a strong indicator that both RNA and DNA developed together and were present in the earliest life forms. Scientists have also suggested that both RNA and DNA might have been combined to form the first genes.  Although no such organism has occurred naturally but a  paper by Scripps Research described an engineered bacteria which can survive with genes formed by a combination of RNA and DNA.

Irrespective of the ways in which life formed, both RNA and DNA with their respective strengths and weaknesses would have arranged themselves into a proper division of labour as evident in the cells today.

Blood vessels 3D rendering

Scientists develop functional blood vessels from cadaver tissues

Blood vessels can be damaged in many conditions such as trauma, cardiac disorders. If they are not repaired in time, it can lead to serious complications. So they can be repaired in two ways, either make a new one or replace it with a vessel from a different body part.

Both the options have their own limitations. Hence researchers are working on a third option, use the blood vessels from a dead body. Humacyte, a medical research company based in North Carolina is working on a new method for replacing blood vessels from tissues of its deceased donors. Their recent trials involving patients with kidney failure have shown positive results. Instead of swapping a damaged vessel with the one from the cadaver, they have developed a model in which the donated cells work in making a protein framework for the patient’s cells to grow.

This method has some great advantages over the the existing methods. If the blood vessels of the body did not work doctors usually found a replacement for them from another body part. The replacement must match the right size and shape, and this involves lot of work. But even then, the replaced vessel might not work and proper grafting may not take place. In some cases, a synthetic vessel can also work if it is replaced for a larger blood vessel, but it gets very risky for smaller blood vessels.

Hence, a midway approach is to make a frame for the blood vessel and let it be populated by the tissues from the patient’s body. This can be either a synthetic one or a framework of proteins from a cadaver.

Superficial blood vessels of the head and neck

Superficial blood vessels of the head and neck( Credits – Wikimedia Commons)

The challenge in this method is to make sure the host cells move into their new ‘home’ and gets repopulated there. It is very crucial to identify which cells take part in the re-population of the implanted material and whether it is successful or not in the patient’s body.

The team at Humacyte seeded smooth muscle cells from cadavers onto a biodegradable mesh. The cells were fed nutrients and it produced a a 3D network of collagen proteins. After the disintegration of the mesh, a protein tube of 420 mm length and 6mm diameter formed. This was termed as human acellular vessel(HAV). All the foreign cells in the HAV were removed as they can be recognised as foreign substance and initiate immune response in the body.

This HAV was implanted in the upper arms of 60 persons with kidney failure. These blood vessels did not generate any significant immune response. Samples of HAV were obtained after a couple of years and it was found that the HAVs were populated with smooth muscle and endothelial cells and microvessels which supplied nutrients to the implant.

Thus the procedure was successful and researchers feel this can now be implemented in hundreds of patients and in future can be used in more complicated injuries such as cardiac injuries.

 

photosynthetic artificial cells

Scientists make photosynthetic artificial cells

Associate professor Yutetsu Kuruma led by his team has created artificial cells that can produce chemical energy that helps synthesize parts of the cells themselves. This research was carried out at the Earth Life science institute located in Tokyo and affiliated to the Tokyo Institute of Technology. This development marks an important revolution in constructing fully photosynthetic artificial cells and may shed light on how primitive and embryonic cells used sunlight as an energy source early in life.

Scientists build artificial cells as models of primitive cells, as well as to appreciate and comprehend how modern cells function. Many sub-cellular systems have been built by simply mixing cell components together. Real living cells construct and consolidate their own components. It is a goal of research to build artificial cells that can also synthesize and their own constituents using the energy available in the environment.

Cell Membranes:
The lipid membranes contain the proteins ATP synthase and bacteriorhodopsin, which is cleansed and purified from living cells. They are designed to work in a cycle, to use light energy to create an energy modification inside the cell, and then to use that energy difference to construct more molecules and more protein.

Throughout the experiments, the photosynthesis process happened as the scientists had anticipated. The artificial cells impersonated and simulated real cells by making messenger RNA (mRNA) from DNA, and then making protein from mRNA. The protocells might have been able to use sunlight to evolve into modern cells only if two of these membrane proteins could produce enough energy to drive gene expression.

Extended Central Dogma with Enzymes

An overview of the central dogma of molecular biochemistry with all unusual flows of information included (in green) (Credit: Dhorspool/ Wikimedia)

The key feature that exists here is the cells’ ability to produce that energy and do their own producing, potentially leading to the conception of independent artificial cells that can be sustained on their own. Although the study wasn’t able to duplicate the full range of proteins that an actual cell can, the researchers think that might happen with an upgraded setup.

The scientists say their work could also be important in the study of protocells, which are evidently thought to have come before modern cells. How did these protocells produce energy to create their own metabolism? This new type of artificial cell might articulate the theory.

Other findings of the research could cover everything from drug delivery to the development of super-smart sensors, and there’s lots more to come yet. And so as the research endures, we might be able to reach and witness the cell development tipping point that happened on the Earth.

So, if scientists build a machine which could produce artificial fruits and vegetables with this technique, would you like to buy it? Tell us with a quick comment.