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Immortal Jellyfish; Is life without death achievable for humans?

To overcome death, start living again from the beginning. If the life secret of immortal Jellyfish, which has made the concepts of immortality and rebirth almost a reality, can’t human beings one day put dust in the eyes of death?

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Image for representation/Pixabay

The secret of immortality has been floating in the ocean all this time, in the form of a jellyfish, while we sifted heaven and science to the ends of the earth for the art of defeating death. Turritopsis dohrnii, also known as the immortal jellyfish, survives death at some point in their lives. Imagine the butterfly turning back into a moth. Or a chicken turning into an egg again. Otherwise, an old man will age and become a fetus again. Although none of these things are happening, this jellyfish will revert to infancy when faced with death. Then will live once more. To know how it is, you need to know the life cycle of the jellyfish.

Turritopsis dohrnii, a member of the Hydrozoa family, prefers warm oceanic habitats. At the same time, they are also found in areas with cold water. They are believed to have originated in the Caribbean and Mediterranean seas. But in recent decades, they have spread to oceans around the world.

Maria Pia Miglietta, a professor of biology at the University of Notre Dame, describes this global spread of jellyfish as a ‘silent invasion’. They have come all over the world clinging to the bottoms of cargo ships. Due to their exceptional ability to survive, in the future there will be no situation in which only immortal jellyfish will exist in the oceans.

Turritopsis dohrnii medusa/Credit: Wikimedia Commons

Their food is small insects in the sea and fish eggs. Turritopsis dohrnii is a very small creature, measuring only 4.5 mm in length and width. There are two stages in their life cycle. The hydroid stage, which grows and colonises through polyps, and the floating medusa stage. In general, everyone is more familiar with the jellyfish’s medusa stage form. A parachute-shaped figure with a balloon-like umbrella on top and fringes hanging down from it.

A jellyfish begins life as a larva called a planula. It is a very small cigar shaped one. They twist and float in the water to find a suitable place to cling to. If it sticks to one place, then the larva turns into a polyp. The polyp has the ability to clone itself. Thus, a colony of polyps is formed by self-replication. They can colonise the entire bottom of a canoe in days. If the conditions are right, the polyps will bloom and the baby jellyfish will emerge. This is where the medusa stage of the jellyfish life cycle begins.

Normally, the medusa of Hydrozoa species produces eggs and spores after they are fully grown. Fertilized ovules become planula. The planula again sticks somewhere and forms a hydroid colony. Polyps form from it and they produce more medusae. This is the typical life cycle of a jellyfish. After reproduction, the medusa will die.

Defeating death

The beginning of a jellyfish’s life is quite ordinary, but the end is quite extraordinary. When the medusa of the immortal jellyfish dies, it sinks to the ocean floor and begins to decompose. But then the miracle happens. From that the cells will be regenerated and thus they will come back to life. Not as new medusa or larvae. As polyps. New jellyfish will hatch from those polyps. This time, jellyfish skip the larval stage and start life as polyps.

Let the miracle of rebirth be there. What is the benefit of this to the jellyfish and why does it do this, these questions are more relevant here. Immortal jellyfish bring out this unique survival strategy and rebirth when faced with danger due to old age, illness, lack of food, or otherwise. Once this process begins, the umbels and fringes on the top of the jellyfish begin to die. It reverts to the polyp state and clings to any surface and comes back to life as a new jellyfish. Jellyfish can repeat this over and over again.

In 1988, Christian Sommer, a German student of marine biology, discovered this immortality of jellyfish completely by accident

How long can this jellyfish live? The answer is how long. These jellyfish were probably still in the oceans when the dinosaurs went extinct 66 million years ago. Biologically, a single immortal jellyfish can live for a long time without dying. Technically they can. But it has not been proved. Because the study of these jellyfish started after 1980s. So, we only have decades of knowledge about them. Moreover, if eaten by other creatures such as fishes, sea turtles, and other jellyfish, their lives will certainly end there.

Who discovered it?

In 1988, Christian Sommer, a German student of marine biology, discovered this immortality of jellyfish completely by accident. Sommer and another student, Giorgio Bavestrello, collected some hydrozoa, which they thought were turritopsis nutricula. Sommer kept the medusa in the lab and watched them until they emerged. Later he forgot about it. But a few days later, Sommer examined the jar in which they were stored and noticed something unusual. These jellyfish exhibit some unusual behaviours. Sommer couldn’t even imagine why that might be. In fact, it seemed to Sommer that they refused to die. A rare phenomenon that occurs backwards in life. They are getting younger and have reached their infancy. There it begins a new life cycle.

But even after a quarter of a century since Christian Sommer made that great discovery, we still haven’t been able to find the secret of the immortal jellyfish’s reincarnation

At the time, Sommer did not realize the significance or magnitude of his discovery. It was only after a century that the name immortal Jellyfish was given to this species. Sommer’s discovery was taken up by biologists. They learned more about this species. Several experimental observations were made. And, in 1996, they published their study under the name ‘Reversing the Life Cycle’. In the study, they explained how this category of jellyfish reverts to the initial polyp stage at some point in their growth. Thus, they escape death and attain immortality, a research paper on the topic says. The discovery challenged the world view that once born there is death.

Can that secret make man immortal?

To overcome death, start living again from the beginning. If the life secret of immortal Jellyfish, which has made the concepts of immortality and rebirth almost a reality, can’t human beings one day put dust in the eyes of death? Should be. Damaged cells in the body can be repaired and regenerated. It can be very crucial in treating and curing deadly diseases like cancer. But even after a quarter of a century since Christian Sommer made that great discovery, we still haven’t been able to find the secret of the immortal jellyfish’s reincarnation.

Immortal jellyfish and some other members of this genus put life into reverse gear when faced with environmental stressors or physical shocks. During this time, a process called cellular transdifferentiation takes place in the organism. It is an unusual phenomenon in which one type of cell changes into another (for example, a skin cell becomes a nerve cell). When this happens, cells produced by cell division change in shape, characteristics, and functions, and they become like sperm cells. In jellyfish, all cells of the medusa stage become cells of the polyp stage. Then the body structure itself changes completely. As seen in the movies. This process is called ontogeny reversal and inverted metamorphosis. An abnormal deviation in the normal life cycle. Each cell contains the information needed to build an organism as a whole. But only a part of this information is used by the jellyfish for ‘rebirth’. Understanding the molecular mechanism in jellyfish that causes ontogeny reversal, instructing all cells to return to infancy, could be the first step towards the ever-greater human goal of ‘immortality’.

Health

UFS study finds emerging pathogen inside brown locusts

Study Reveals Brown Locusts as Carriers of Pathogenic Yeasts Linked to Human Infections

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Prof Carlien Pohl-Albertyn is the NRF SARChI Research Chair in Pathogenic Yeasts at the UFS. By special arrangement

A new study conducted by researchers from the University of the Free State (UFS), the National Health Laboratory Service, and the University of Venda has revealed for the first time that common brown locusts can carry pathogenic yeasts, including Candida auris, a fungus capable of causing severe infections in humans, particularly in individuals with weakened immune systems or those seriously ill.

The study, titled South African brown locusts, Locustana pardalina, hosts fluconazole-resistant, Candidozyma (Candida) auris (Clade III), uncovers the presence of the disease-causing yeast C. auris in the digestive tracts of locusts. This discovery highlights the potential for locusts to spread this emerging pathogen. The research began in April 2022, with 20 adult locusts collected during a significant locust outbreak in the semi-arid Eastern Karoo region of the Eastern Cape, which lasted from September 2021 to May 2022. The study is currently under peer review.

According to Prof. Carlien Pohl-Albertyn, National Research Foundation (NRF) SARChI Research Chair in Pathogenic Yeasts, the researchers isolated three strains of C. auris from different locusts, two of which also contained strains of Candida orthopsilosis, another potentially pathogenic yeast. “The fact that we were able to isolate C. auris from 15% of the sampled locusts, using non-selective media and a non-restrictive temperature of 30°C, may indicate that C. auris is abundant in the locusts and that specific selective isolation is not mandatory,” said Prof. Pohl-Albertyn.

Brown locusts sold as food at a market in Nigeria. Credit: UFS

The study also found C. auris in both the fore- and hindguts of the locusts. The foregut, responsible for food intake and partial digestion, likely serves as the entry point for the yeast via the locust’s feeding activities. The hindgut confirmed that C. auris can survive digestion and may be excreted back into the environment through faeces.

While C. auris poses a significant risk to individuals with compromised immune systems, Prof. Pohl-Albertyn emphasized that healthy humans are not at great risk. “There is currently no proof that ingestion may be harmful to them,” she explained. However, she warned that the yeast could pose dangers to immunocompromised individuals, even though few people in South Africa are in direct contact with locusts.

One of the C. auris strains studied in-depth showed decreased susceptibility to fluconazole, a common antifungal drug, underscoring the need for new antifungal treatments. “This highlights the urgent need to discover and develop new antifungal drugs,” Prof. Pohl-Albertyn added.

The study also raises concerns about how locusts could potentially spread C. auris to other animals, such as birds, and, in some regions, even humans. “The fact that locusts are a food source for other animals could lead to eventual distribution of the yeast to people,” Prof. Pohl-Albertyn noted. In countries where locusts are consumed by humans, direct transmission could be more likely.

This research contributes to understanding the natural hosts of emerging pathogens and their role in spreading these diseases. Prof. Pohl-Albertyn emphasized the importance of understanding how C. auris emerged as a pathogen in multiple countries and how environmental factors may have shaped its evolution. “This has implications for the prevention of the spread of this specific yeast species, as well as our preparedness for new pathogenic yeasts that may be emerging from the environment,” she concluded.

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Health

IITK Researchers Unveils Key Receptor Structure for Cancer and Respiratory Treatments

The team successfully visualized the atomic structure of CXCR2, a crucial human receptor involved in the progression of cancer and respiratory diseases

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GPCR Lab. Image credit: By special arrangement

Researchers from the Department of Biological Sciences and Bioengineering at the Indian Institute of Technology (IIT) Kanpur have made a path breaking discovery that could pave the way for new treatments for cancer and respiratory diseases. The team successfully visualized the atomic structure of CXCR2, a crucial human receptor involved in the progression of these diseases. Their findings, published in the prestigious journal Molecular Cell, offer a new perspective on targeting this receptor for therapeutic intervention.

CXCR2 is a key receptor in the immune system, involved in directing immune cells to infection and injury sites through interaction with chemokines—small signaling proteins. CXCR2’s role in inflammatory disorders and cancers such as chronic obstructive pulmonary disease (COPD), asthma, atherosclerosis, and pancreatic cancer makes it a promising target for new drugs.

Using advanced cryogenic-electron microscopy (cryo-EM), the IIT Kanpur researchers captured unprecedented details of the receptor’s “lock-and-key” mechanism, shedding light on how CXCR2 interacts with multiple chemokines. This discovery addresses a fundamental question in biomedical science about how a single receptor can bind to various chemokines and trigger biological responses. The visualization also opens up opportunities for designing novel therapeutics.

“Our findings provide a molecular blueprint for designing next-generation therapeutics that can precisely target CXCR2 and potentially reduce its role in cancer and respiratory diseases. By visualizing this receptor in its active state, we now have the opportunity to develop highly specific inhibitors that can disrupt its function, potentially leading to significant advancements in treatment strategies,” said Professor Arun Kumar Shukla, the lead investigator of the study at IIT Kanpur.

The research team at IIT Kanpur includes Shirsha Saha, Saloni Sharma, Manisankar Ganguly, Nashrah Zaidi, Divyanshu Tiwari, Nabarun Roy, Nilanjana Banerjee, and Ramanuj Banerjee. Their work also involved collaboration with experts from the University of Tokyo, Japan—Fumiya Sano, Hiroaki Akasaka, Takaaki Kobayashi, Yuzuru Itoh, Wataru Shihoya, and Osamu Nureki—along with Andy Chevigne from the Luxembourg Institute of Health.

This study was funded by the DBT Wellcome Trust India Alliance, Science and Engineering Research Board (SERB), Indian Council of Medical Research (ICMR), and LADY TATA Memorial Trust.

Building on this discovery, the IIT Kanpur team is now developing small molecules and antibodies aimed at targeting CXCR2. These therapeutics will undergo laboratory testing, followed by animal studies, bringing the team closer to offering innovative treatments for cancer and respiratory diseases. This achievement further underscores IIT Kanpur’s commitment to pioneering research that has the potential to revolutionize global healthcare and biomedical innovation.

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Learning & Teaching

Canine Cognitive Abilities: Memory, Intelligence, and Human Interaction

Research on canine cognition shows that dogs have impressive memory retention, which helps them recognize faces, remember commands, and understand their environment.

Ajith Madhavan

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Image: Lazyboness from Pixabay

Dogs are renowned for their ability to adapt and respond to various situations. One of the key features of their intelligence is their memory and how they utilize past experiences to navigate new circumstances. Dogs not only remember specific events but also use those memories to make decisions in future situations. Research on canine cognition shows that dogs have impressive memory retention, which helps them recognize faces, remember commands, and understand their environment. When faced with a new scenario, they often recall previous similar experiences and apply those learnings effectively.

Understanding Human Cues: A Result of Evolution

Dogs’ remarkable ability to understand human cues—whether through body language, vocal tones, or facial expressions—is another significant aspect of their cognitive prowess. Over thousands of years of domestication, dogs have learned to interpret human signals, making them highly attuned to the needs and intentions of their human companions. This phenomenon is often attributed to the domestication hypothesis, which suggests that dogs have evolved alongside humans and, in doing so, developed the ability to read and respond to human cues.

Image: Zigmars Berzins from Pixabay

However, some researchers argue that dogs’ ability to understand human cues might not solely stem from domestication. There is a possibility that dogs’ social intelligence could be a result of convergent evolution, where dogs’ cognitive abilities have evolved similarly to those of social animals like primates, despite not sharing a direct evolutionary path. This perspective is still debated in the field, but it underscores the complexity of understanding the roots of canine cognition.

Cognitive Categories in Dogs: Classifying Intelligence

Dogs’ cognitive abilities can be broken down into various categories that reflect the diversity of their intelligence. These categories help researchers study the different aspects of how dogs think, learn, and behave. Some of the key categories include:

• Spatial Intelligence: Dogs possess a strong sense of spatial awareness, allowing them to navigate their environment effectively. They can remember the locations of objects such as toys, food bowls, and leashes. This spatial awareness also extends to their ability to assess distances and understand their surroundings. While most dogs develop this intelligence naturally, some may need training to enhance their spatial skills.

• Intrapersonal Intelligence: This refers to a dog’s ability to understand its own physical abilities, limitations, and needs. For example, a dog might avoid attempting an action, such as jumping over a large gap, if it perceives it to be beyond its capabilities. This form of intelligence reflects the dog’s self-awareness, although the level of this awareness may differ from that seen in humans. Dogs might not have conscious self-reflection, but their behavior indicates an understanding of their limits.

• Interpersonal Intelligence: Dogs are highly social animals, and their interpersonal intelligence is reflected in their ability to communicate with both humans and other dogs. They can interpret social cues and respond accordingly, forming strong bonds with their human families and understanding the dynamics of their social group. This intelligence is particularly evident in their interactions with humans, where they not only respond to verbal commands but also tune into human emotions, following social hierarchies and giving appropriate responses. For example, dogs can respond to human emotions by offering comfort or adjusting their behavior based on the emotional state of their human companions.

The Role of Human-Dog Interaction in Cognitive Development

Dogs’ cognitive abilities, including their ability to understand human emotions, are likely a product of their long history of living alongside humans. Studies show that dogs can often read the intentions of humans, making them exceptionally skilled at interpreting social cues. This human-dog bond has shaped dogs’ social intelligence, allowing them to be highly responsive to the emotional and social cues provided by humans. For instance, when a human expresses frustration or joy, a dog can often sense the change in mood and react accordingly, whether by offering comfort or simply adjusting their behavior.

Interestingly, some studies suggest that domestic dogs might lose some of their problem-solving abilities when raised solely in human environments. This loss might occur because dogs begin to rely on human intervention for problem-solving, rather than using their independent cognitive skills. However, with appropriate training and stimulation, many dogs can retain or even develop complex problem-solving abilities.

Variations and Training

Just as with humans, not all dogs display the same level of cognitive abilities. Some dogs might struggle with spatial awareness or might not respond to certain social cues as effectively as others. This is particularly evident in some breeds or individual dogs that may require additional training to enhance these skills. Spatial awareness, for example, might be challenging for dogs that were not raised in environments where they had to navigate complex spaces. Training exercises can help improve these cognitive areas, allowing the dog to become more aware of its surroundings and capable of responding appropriately.

The Kombai or Polygar is a breed of working dog native to Tamil Nadu in Southern India. Credit: Ajith Madhavan

Moreover, self-awareness or intrapersonal intelligence can also vary among dogs. While some dogs might instinctively understand their physical limitations (e.g., recognizing when they can’t jump a certain height), others may require repeated experiences to learn these boundaries.

Complex and Multifaceted

Overall, dogs exhibit a wide range of cognitive abilities that demonstrate both adaptive intelligence and social prowess. Their ability to learn, remember, and apply past experiences to new situations showcases their problem-solving skills, while their social intelligence allows them to communicate effectively with humans and other dogs. While there is still much to learn about the origins and evolution of canine intelligence, it is clear that dogs have evolved to become highly adept at interpreting the world around them, both physically and socially.

Image: Anja from Pixabay

The domestication of dogs, along with their interaction with humans, has contributed significantly to the development of their cognitive abilities. These abilities are not only a result of their domesticated lives but also a product of their evolutionary adaptation to social living, both with humans and other animals. Understanding these cognitive abilities in dogs helps deepen the bond between dogs and humans and enriches our appreciation for these remarkable companions.

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