Circadian Rhythm Prof

2 Science Horizon Volume 2 Issue 10 October, 2017 President, Odisha Bigyan Academy Editorial Board Prof. Sanghamitra Mohanty Prof. Rama Shankar Rath Chief Editor Er. Mayadhar Swain Prof. Niranjan Barik Prof. G. B. N. Chainy Editor Dr. Trinath Moharana Prof. Tarani Charan Kara Prof. Madhumita Das Managing Editor Prof. Bijay Kumar Parida Dr. Prafulla Kumar Bhanja Secretary, Odisha Bigyan Academy Dr. Shaileswar Nanda CONTENTS Subject Author Page 1. Editorial : Neuroplasticity - An Overview Prof. Tarani Charan Kara 1 2. Nobel Prize in Physiology or Medicine, 2017 Dr. Niraj K. Tripathy 3 3. Circadian Rhythm Prof. G.B.N. Chainy 6 4. Timeline of Nobel Prize in Physiology and Medicine Abhaya Kumar Dalai 9 5. Loss of Memories "Alzheimer" Prof. (Dr.) Saileswar Nanda 11 6. Health Problems of Elderly Persons Dr. Kalyanee Dash 13 7. Nanomedicine : An Overview Binapani Mahaling 16 Aumreetam Dinabandhu 8. Nutritive Value of Poultry Egg Dr. B. C. Das 21 Dr. K. K. Sardar 9. Human Agenda for Twenty First Century Dr. Soumendra Ghosh 25 10. Protected Cultivation : Scope and Importance Mir Miraj Alli 27 Anwesha Dalbehera 11. The Red Pearl on the Greenery Prof. Animesh K. Mohapatra 32 Saptabarna Mukherjee 12. Artificial Light Pollution : A Problem for All Dr. Tapan Kumar Barik 36 13. Science in Search of Missing Netaji Dr. Nikhilanand Panigrahy 40 14. Galileo Galilei - The Father of Modern Science Prof. Ramsankar Rath 43 15. Detection of Evidence for the Existence of New Planets Dr. Sadasiva Biswal 45 16. Quiz : Computer Science & Information Technology Sri Sai Swaroop Bedamatta 47 The Cover Page depicts : Structure of Brain and Neural Synapsis Cover Design : Sanatan Rout neutron star EDITORIAL NEUROPLASTICITY - AN OVERVIEW Brain, the centre of the nervous system in all are not fixed, but appearing and disappearing vertebrates, is perhaps the most complex of biological dynamically throughout the life. Brain needs training to structures. It has multiple components that together maximize its potential. Now it has been recognized that regulate, both, the emotive as well as the higher functions engagement in thinking, acting and learning result in i.e. cognitive once. significant changes of both the physical structure and The seat of these higher functions is not confined function of the brain. When one activity is repeatedly to a single part of the brain. Many parts of the brain are performed, neuronal circuits are being formed, leading responsible for them, but together they constitute a single to better ability to perform the particular task. subsystem called the limbic system, which includes the During the first few years of our early life, the brain hippocampus and the amygdala. The amygdala, which grows rapidly. As each neuron matures, it sends out is as little as an almond, is located deep within the brain multiple branches (axons and dendrites), increasing the below the hippocampus. While the hippocampus is number of synaptic (neuronal junctions) contacts from associated with complex cognitive processing, learning neuron to neuron. However, with advancing age, the and memory, the amygdale is involved in complex ineffective or weaker synaptic connections are deleted emotional responses, such as fear, anxiety, aggression through synaptic pruning, while connections that have and long-term memories. Although major advancements been activated most frequently are strengthened and have been made in the understanding of how the brain preserved. There are several underlying mechanisms that functions, a lot more are yet to be revealed. regulate the synaptic plasticity which is supposed to be It was earlier believed that in youth, the human an important neurochemical basis for learning and memory. mind achieved its maximum growth and thereafter it Further, research on brain development indicated starts declining with age, illness and injury and as we that there are stem cells in the brain which remain active grow old, neural networks of the brain become fixed. throughout life. These stem cells produce neural or glial However, the research work conducted in the last three progenitor cells that migrate into the cerebral white or decades has revealed that the brain never stops changing and it adapts itself to new changes due to Neuroplasticity. gray matter, even in adult stage. There, these cells remain Neuroplasticity is the ability of our brain to change its quiescent for extended periods but can convert into either structure and functions in response to outer experiences, neuron and/or glia on activation. These cells form the new learning and even to inner aspirations (as mentioned basis of postnatal neurogenesis, especially after the brain by Sri Aurobindo, Paramahansa Yogananda and others). injury. In addition, the mammalian brain, can generate When anyone learns a novel skill, new neural pathways neurons that are destined to form the olfactory lobe, are formed in their brain leading to a structural change. hippocampal and possibly other negions even in adulthood. Further, if a particular part of the brain gets damaged Another special feature is that dendrites and its due to injury or illness, then other areas of the brain spines show remarkable degree of plasticity in response takeover that function with equal proficiency. to experience and can form new neural connections Our brain is constantly changing i.e. both within hours and possibly even minutes after some neurogenesis and neuronal death occur throughout life. experiences. The brain does continue to form synapses However, during fetal development structural changes throughout the lifetime and these synapses are actually such as neurogenes is and neuronal migrations are necessary for the process of learning and memory. dominant. While in adult brain the functional neuroplasticity Thus the experiences gained during the life period is dominant, allowing the brain to constantly adapts to of an individual are changing the neural networks by environment and injury. Thus brain has a possibility of both adding and pruning synapses leading to remodeling its own neural circuits to regain the lost neuroplasticity. Scientific research in neuroplasticity is functions caused by neurologic deficit or brain damage. still in its early stages and perhaps we are not yet aware Neuroplasticity is the lifelong ability of the brain of the potential of our brain. Once we learn to exercise to change and reorganize for better adaptability to new the power of our mind a lot of negative emotions, unhealthy situations. It is a functional reorganization within neural habits and psychological disorders can be eliminated, tissue, mediated by changes in neural networks which helping the humanity to lead a Godly life on earth. Prof. Tarani Charan Kara e-mail : [email protected] OCTOBER, 2017 NOBEL PRIZE IN PHYSIOLOGY OR MEDICINE, 2017 Dr. Niraj K. Tripathy The Nobel Committee of Karolinska genetically controlled patterns of sleep and Institute on the 2nd of October, 2017 has wakefulness in Drosophila melanogaster. He announced the Nobel Prize in Physiology or has elucidated the function of period gene, Medicine for this year. It has been awarded to necessary for the fly to exhibit normal sleep three American biologists jointly. They are cycles. All the three of them were elected to Professor Jeffrey Connor Hall, Michael the National Academy of Sciences and were Morris Rosbash and Michael Warren Young recipients of Gruber Prize in 2009, Shaw prize for their work on molecular mechanisms and Wiley Prize in 2013 besides receiving controlling the circadian rhythm. several other awards. A circadian rhythm is a biological process that displays an endogenous, entrainable oscillation of about 24 hours. The term circadian comes from the Latin words circa, meaning "around" (or "approximately"), and diem or dies, meaning "day". The term Jeffrey C. Hall Michael Rosbash Michael C. Young "circadian" was coined by Franz Halberg in Jeffrey Hall (72), a Geneticist and the late 1950s. The earliest known account of Chronobiologist, is a Professor Emeritus at a circadian process dates back to the 4th Brandeis University, USA. At the time of century BC, when Androsthenes, a ship award he was affiliated to the University of captain serving under Alexander the Great, Maine, USA. described diurnal leaf movements of the Michael Rosbash (73), also a Geneticist tamarind tree. and Chronobiologist, is a Professor at The first recorded observation of an Brandeis University and an investigator at the endogenous circadian oscillation was made Howard Hughes Medical Institute. He had by the French scientist Jean-Jacques d'Ortous cloned the period gene in Drosophila in 1984 de Mairan in 1729 who observed that the and proposed the transcription translation leaves of Mimosa plants open towards the negative feedback loop. sun during daytime and close at dusk. He Michael Young (68), a biologist and observed that the leaves of this plant followed geneticist is affiliated to Rockefeller their normal daily oscillation independent of University, USA. For over three decades he daily sunlight and thus opined that these has dedicated himself to the study of plants have their own biological clock. It has Science Horizon 2 OCTOBER, 2017 been shown that not only plants but also Rockefeller University isolated the period animals including humans have biological gene. Hall and Rosbash discovered PER, the clocks which help them make physiological protein encoded by the period gene. They adjustment in accordance with the fluctuations showed that PER protein levels oscillate over of the day light. Thus they exhibit circadian a 24-hour cycle, in synchrony with the rhythm. Patterns of activity, with periodicities circadian rhythm and that it was accumulated of approximately 24 hours appear to be during night and degraded during the day. universal components of animal behaviour They hypothesised that the PER protein blocks (Pittendrigh, 1974). Circadian rhythms the activity of the PER gene through an influence behaviour and many physiological inhibitory feedback loop which prevents its processes. These rhythms are created by an own synthesis.Thus it regulates its own level endogenous circadian clock that persists in a continuous cyclic rhythm.

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