- Stem cells are the body’s raw materials — cells from which all other cells with specialized functions are generated.
- Under certain conditions in the body or a laboratory, stem cells divide to form more cells called daughter cells.
- These daughter cells either become new stem cells (self-renewal) or become specialized cells (differentiation) with a more specific function, such as blood cells, brain cells, heart muscle cells or bone cells.
- No other cell in the body has the natural ability to generate new cell types.
Types of cells
Stem cells are of the following different types:
- Embryonic Stem Cells
- Adult Stem Cells
- Induced Pluripotent Stem Cells
- Mesenchymal stem cells
Embryonic Stem Cells
The fertilized egg begins to divide immediately. All the cells in the young embryo are totipotent cells. These cells form a hollow structure within a few days. Cells in one region group together to form the inner cell mass. This contains pluripotent cells that make up the developing foetus.
The embryonic stem cells can be further classified as:
- Totipotent Stem Cells: These can differentiate into all possible types of stem cells.
- Pluripotent Stem Cells: These are the cells from early embryo and can differentiate into any cell type.
- Multipotent Stem Cells: These differentiate into a closely related cell type. For eg., the hematopoietic stem cells differentiate into red blood cells and white blood cells.
- Oligopotent Stem Cells: Adult lymphoid or myeloid cells are oligopotent. They can differentiate into a few different types of cells.
- Unipotent Stem Cells: They can produce cells only of their own type. Since they have the ability to renew themselves, they are known as unipotent stem cells. For eg., Muscle stem cells.
Adult Stem Cells
These stem cells are obtained from developed organs and tissues. They can repair and replace the damaged tissues in the region where they are located. For eg., hematopoietic stem cells are found in the bone marrow. These stem cells are used in bone marrow transplants to treat specific types of cancers.
Induced Pluripotent Stem Cells
These cells have been tested and arranged by converting tissue-specific cells into embryonic cells in the lab. These cells are accepted as an important tool to learn about normal development, onset and progression of the disease and also helpful in testing various drugs. These stem cells share the same characteristics as embryonic cells do. They also have the potential to give rise to all the different types of cells in the human body.
Mesenchymal Stem Cells
These cells are mainly formed from the connective tissues surrounding other tissues and organs known as stroma. These mesenchymal stem cells are accurately called stromal cells. The first mesenchymal stem cells were found in the bone marrow that are capable of developing bones, fat cells, and cartilage.
There are different mesenchymal stem cells that are used to treat various diseases as they have been developed from different tissues of the human body. The characteristics of mesenchymal stem cells depend on the organ from where they originate.
What is stem cell therapy?
- Stem cell therapy, also known as regenerative medicine, promotes the repair response of diseased, dysfunctional or injured tissue using stem cells or their derivatives.
- Stem cells can then be implanted into a person. For example Mumbai baby boy was injected with 40 million stem cells and gradually the lungs began to repair. In this case, doctors used mesenchymal stem-cell therapy (these are adult stem cells and are different from Embryonic stem cells) on an experimental basis
Why it is an issue?
- In March 2019, the Union Health Ministry had notified the ‘New Drugs and Clinical Trial Rules, 2019’ which state that stem-cell derived products are to be used as “new drugs”. “This means that any doctor who uses stem-cell therapy needs to take permission from the government.
Advantages of Stem cell Therapy:
- Immense Medical Benefits: It offers a lot of medical benefits in the therapeutic cloning and regenerative medicine
- Treatment of Conditions and Disorders: It shows great potential in the treatment of a number of conditions like Parkinson’s disease, spinal cord injuries, Alzheimer’s disease, schizophrenia, cancer, diabetes and many others.
- A Better Knowledge of human growth: It helps the researchers know more about the growth of human cells and their development.
- The stem cell research can allow the scientists to test a number of potential medicines and drugs without carrying out any test on animals and humans. The drug can be tested on a population of cells directly.
- Cure development defects before they happen: The stem cell therapy also allows researchers to study the developmental stages that cannot be known directly through the human embryo and can be used in the treatment of a number of birth defects, infertility problems and also pregnancy loss. A higher understanding will allow the treatment of the abnormal development in the human body.
- Reduced risk of rejection: The stem cell therapy puts into use the cells of the patient’s own body and hence the risk of rejection can be reduced because the cells belong to the same human body.
Challenges in SCT
- Destruction of blastocysts: The use of the stem cells for research involves the destruction of the blastocysts that are formed from the laboratory fertilization of the human egg.
- Unknown side-effects: Like any other new technology, it is completely unknown what the long-term effects of such an interference with nature could be
- Limitations of adult cells: The disadvantage of adult stem cells is that the cells of a particular origin would generate cells only of that type, like brain cells would generate only brain cells and so on.
- Potential Rejection: If the cells used in the therapy are embryonic, then the cells will not be from the same human body and there are chances of rejection.
- Potential use in negative activities: It can be used to create bio-weapons or weapons of mass destruction
Applications of SCT
- Orthopedic injuries and musculoskeletal problems
- Wounds and incisions following surgeries
- Spinal cord injuries, brain trauma and spinal stenosis
- Cardiovascular diseases, including hypertension, coronary heart disease, stroke and congestive heart failure
- Hair loss
- Vision impairment
- Diabetes and other pancreatic dysfunctions
- Neurodegenerative diseases such as Parkinson’s, multiple sclerosis and Alzheimer’s
India and Stem Cell Therapy
- According to the Indian Council of Medical research, all stem cell therapy in India considered to be experimental except bone marrow transplants
- Stem cell therapy is legalized in India
- Umbilical cord and adult stem cell treatment are considered permissible
- Embryonic stem cell therapy and research is restricted
CHINA’S GENE EDITING RULES
China has decided to introduce new Gene-editing rules.
- Rules require researchers to obtain prior approval from the government before undertaking clinical trials.
- Those found violating the rules will be punished and this includes a lifetime ban on research.
- The rules would also require all future trials to be approved by administrative authorities as well as ethical committees.
- Last year, a chinese researcher, He Jiankui, has claimed that he used CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) to produce the world’s first gene-edited babies to make babies immune to infection by the human immunodeficiency virus (HIV).
- After the news of gene-edited babies came Chinese national health commission investigated and found that Dr. He had violated the national regulations against using gene-editing for reproductive purposes.
- China has now decided to come up with stricter norms regarding gene editing.
- Gene editing is also called as genetic modification, genetic manipulation or genetic engineering.
- Genome editing is a group of technologies that give scientists the ability to change an organism’s DNA (Deoxyribonucleic acid). These technologies allow genetic material to be added, removed, or altered at particular locations in the genome.
- Gene Editing is widely practised in agriculture, to increase productivity or resistance to diseases, etc.
What is CRISPR?
- Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) is a gene editing technology, which replicates natural defence mechanism in bacteria to fight virus attacks, using a special protein called Cas9.
- CRISPR-Cas9 technology behaves like a cut-and-paste mechanism on DNA strands that contain genetic information. The specific location of the genetic codes that need to be changed, or edited, is identified on the DNA strand, and then, using the Cas9 protein, which acts like a pair of scissors, that location is cut off from the strand.
- A DNA strand, when broken, has a natural tendency to repair itself. Scientists intervene during this auto-repair process, supplying the desired sequence of genetic codes that binds itself with the broken DNA strand.
- CRISPR-Cas9 is a simple, effective, and incredibly precise technology with potential to revolutionise human existence in future.
- Dr. He used the CRISPR–Cas9 gene editing technique to disable a gene called CCR5 (C-C chemokine receptor type 5), which encodes a protein that allows HIV to enter and infect cells.
- Though no guidelines have been drawn up so far regarding gene editing.
- There is a general consensus in the scientific and ethics communities that the CRISPR–Cas9 gene-editing technique should not be used clinically in embryos..
- Importantly, human clinical trials have not been carried out anywhere in the world to test whether disabling the gene completely prevents HIV infection.
- In the absence of any clinical trial data as well as consensus to use this tool to prevent HIV infection, performing it on babies as a form of medical intervention is unethical.
- C-C chemokine receptor type 5, also known as CCR5 or CD195, is a protein on the surface of white blood cells that is involved in the immune system as it acts as a receptor for chemokines.
- CCR5, which encodes a protein that allows HIV to enter and infect cells. The CCR5 gene protective role against the West Nile virus is well established.
- The CCR5 gene also helps to protect the lungs, the liver and the brain during certain serious infections and chronic diseases.
- The gene is known to prompt the immune system to fight the influenza virus in the lungs.
RNA INTERFERENCE (RNAi)
RNAi is a gene silencing technology that inhibits protein synthesis in target cells using double-stranded RNA. Same result is achieved by Antisense technology through single-stranded RNA.
- RNAi technologies are now known to formulate drugs capable of reducing cholesterol levels by half. The technology also finds immense importance in treating acute viral infections like acquired immunodeficiency syndrome (AIDS), because of the well-studied life cycle and pattern of gene expression of the human immunodeficiency virus (HIV).
- Promising results have been shown by Antisense technology in producing a variety of tomato with increased shelf-life commonly known as Flavr Savr.
- It can be said that, in the near future, antisense technology could be used in targeting cancer.
Constraints hampering the growth of these technologies in India:
- Very few companies working with these technologies in India.
- Poor translation of this nucleic-acid based therapy to clinical studies.
- Lack of efficient and targeted delivery vehicles for these potential RNA molecules. Though this is one of the objectives of a stand-alone programme on nano-biotechnology under department of biotechnology, research gaps continue to exist.
- The relatively minimal development of silencing reagents that ensure significant, specific, consistent and lasting knockdown of the target gene.
Gene Silencing Technique
- Gene silencing is a technique that aims to reduce or eliminate the production of a protein from its corresponding gene.
- It generally describe the “switching off” of a gene by a mechanism other than genetic modification
- It occurs when RNA is unable to make a protein during translation (gene expression).
- In the groundnut case, the researchers designed two small RNA molecules that silence the fungal genes which produce aflatoxin.
- When the fungus and plant come in contact with each other the small RNA molecules from the plant enter the fungus and prevent it from producing aflatoxin (protein) by its corresponding gene.
GENETICALLY MODIFIED AEDES AEGYPTI
What is the initiative?
- Aedes aegypti mosquito is the carrier of diseases such as Zika, dengue and chikungunya.
- A new initiative thus aims at reducing the population of Aedes aegypti mosquito.
- It comes from the Mumbai-based company, Gangabishan Bhikulal Investment and Trading Limited (GBIT).
What is the new gene?
- Diseases such as Zika, dengue and chikungunya are transmitted when an infected, pregnant female mosquito bites somebody.
- Males do not bite and are, therefore, harmless.
- So GBIT wants to introduce a new Genetically Modified (GM) male Aedes aegypti mosquito.
- This GM insect has been bred by Oxitec, an R&D biotech company with roots in the University of Oxford.
- Oxitec has bio-engineered a transgenic male Aedes aegypti mosquito.
- This carries a new gene fatal only to female mosquitoes.
What does it do?
- The idea is to release a large number of such GM male mosquitoes into the trial zone.
- These will then breed with normal females in the wild.
- In the next generation, only the males would survive and these would breed again, with normal females.
- After a few generations, the female population will be drastically reduced.
- Eventually this cycle will result in a reduction of the entire mosquito population.
- Zika virus is a mosquito-borne flavivirus that was first identified in Uganda in 1947 in monkeys.
- It was later identified in humans in 1952 in Uganda and the United Republic of Tanzania. Outbreaks of Zika virus disease have been recorded in Africa, the Americas, Asia, and the Pacific.
- Zika virus disease is caused by a virus transmitted primarily by Aedes mosquitoes and can be passed from a pregnant woman to her foetus.
- Sexual transmission of Zika virus is also possible.
- There is no vaccine or medicine for Zika. Instead, the focus is on relieving symptoms and includes rest, rehydration and acetaminophen for fever and pain.
- Dengue is transmitted by several species of mosquito within the genus Aedes.
- Symptoms include fever, headache, muscle, and joint pains, and a characteristic skin rash that is similar to measles.
- Dengvaxia is the first dengue vaccine but the Indian drug controller has yet to grant approval to it.
- India has reported 6,210 cases and six deaths from dengue until June 9, 2019.
- Chikungunya is caused by a mosquito-borne virus.
- It is transmitted by Aedes aegypti and Aedes albopictus mosquitoes.
- Its symptoms are characterized by abrupt fever and severe joint pain, often in hands and feet, and may include headache, muscle pain, joint swelling or rash.
- There is no specific antiviral drug treatment for chikungunya.
- There is no commercial chikungunya vaccine.
- An 11-year-old has become the first patient to receive CAR-T therapy (immunotherapy) that uses the body’s own cells to fight cancer.
- CAR-T is a personalized form of cancer treatment.
- CAR-T involves removing immune cells and modifying them in a laboratory so they can recognize cancer cells.
- Immunotherapy is treatment that uses your body’s own immune system to help fight cancer
- First, the patient has blood removed and the white blood cells are separated out, with the rest of the blood being returned to the patient.
- A harmless virus is used to insert genes into T-cells, a special type of immune cell.
- These genes cause the T-cells to add a hook on to their surface, known as a chimeric antigen receptor (CAR).
- These engineered CAR-T cells – programmed to recognize and destroy the patient’s cancer cells – are multiplied in huge numbers and then infused back into the patient.
DANGERS OF ARTIFICIAL RIPENING OF FRUITS AND VEGETABLES
- Fruits are a good source of vitamins and minerals and play an important role in preventing Vitamin C and A deficiencies.
- WHO recommends 5 servings of fruits and vegetables every day for a healthy living.
- However, the health benefits of fruits depend on how they are ripened.
- The best course will be to allow them to ripen on the plant itself.
- The fruits become soft, change in colour and develop aroma with an increase in sugar level and reduction in acid content.
- Many factors influence the process of ripening including temperature and relative humidity.
- It is not always possible to wait for the fruit to ripen naturally.
- More often than not, they need to be transported over long distances.
- If they had been harvested in a ripe stage, they get spoilt before reaching their destination.
- For such situations, farmers harvest them much before they get ripe.
- The traders then ripen them artificially at the destination using certain chemicals.
- Most fruits produce a gaseous compound called ‘ethylene’ that starts the ripening process.
- Its level in under-ripe fruit is very low, but as the fruits develop, they produce larger amounts of the chemical that speeds up the ripening process.
- These enzymes convert complex polysaccharides into simple sugars and make the skin of the fruits soft.
- In artificial ripening, this process is mimicked using chemicals.
- The most commonly used chemical is called ‘ethephon’ (2-chloroethyl phosphonic acid).
- It penetrates into the fruit and decomposes ethylene.
- Another chemical that is regularly used is ‘Calcium carbide’, which produces ‘acetylene’, which is an analogue of ‘ethylene’.
- It is, however, fraught with several problems.
- Studies have shown that it breaks down the organic composition of vitamins and other micronutrients.
- Besides, it changes only the skin colour, the fruit remains raw inside.
- Industrial grade calcium carbide is often found contaminated with traces of arsenic and phosphorus which are toxic chemicals.
- The symptoms of arsenic and
phosphorous poisoning include,
1) Vomiting, diarrhoea with/without blood, weakness, burning sensation in the chest and abdomen, eye damage, ulcers.
- According to studies, Calcium carbide can also affect the neurological system.
- FSSAI has banned calcium carbide under the “Prevention of Food Adulteration (PFA) Act, 1954”.
- To distinguish the artificially ripened fruit,
2) They will have uniform skin colour in fruits like tomato, mango, papaya, and in the case of banana,
3) The fruit will be yellow while the stem will be dark green.
4) If the fruits are available before season, it could mean they are artificially ripened.
- Washing and peeling the fruits before eating can minimise the risks of calcium carbide.
- Leucine-rich repeat kinase 2 (LRRK2) is a kinase enzyme that protects the body against viral and bacterial infections by triggering inflammation like swelling, redness, heat and pain.
- According to a recent study, this enhanced inflammation can lead to collateral damage to the body.
- Inflammation caused by mutation in a gene can raise the risk of Parkinson’s and Crohn’s diseases as well as leprosy.
- Leprosy caused by infections characterised by lesions in the nerve endings of the skin.
- LRRK2, which causes excessive inflammation to defend body against a type of mycobacterium infects peripheral nerves, is thought to be behind leprosy.
- The findings are also important for ongoing clinical trials of Parkinson’s drugs that can reduce excessive LRRK2 activity.
- However, total absence of LRRK2 function can make people more prone to infections.
LRRK2 was recently on science news portals, it is a
- Kinase enzyme
‘IndiGen’ GENOME PROJECT
The initiative was implemented by the CSIR-Institute of Genomics and Integrative Biology (IGIB), Delhi and CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad.
Significance, outcomes and benefits of the project:
The outcomes of the IndiGen will have applications in a number of areas including predictive and preventive medicine with faster and efficient diagnosis of rare genetic diseases.
The data will be important for building the knowhow, baseline data and indigenous capacity in the emerging area of Precision Medicine.
About Genomics for Public Health in India (IndiGen) programme:
IndiGen programme aims to undertake whole genome sequencing of thousands of individuals representing diverse ethnic groups from India.
The objective is to enable genetic epidemiology and develop public health technologies applications using population genome data.
Need for genome sequencing:
- Ever since the human genome was first sequenced in 2003, it opened a fresh perspective on the link between disease and the unique genetic make-up of each individual.
- Nearly 10,000 diseases — including cystic fibrosis, thalassemia — are known to be the result of a single gene malfunctioning.
- While genes may render some insensitive to certain drugs, genome sequencing has shown that cancer too can be understood from the viewpoint of genetics, rather than being seen as a disease of certain organs.
Genome India project:
- It is funded by the Department of Biotechnology (DBT) to sequence at least 10,000 Indian genomes.
- 22 partner organisations including public health institutions will be roped in that have obtained regulatory ethical clearances.
- Investigators in hospitals will lead the data collection through a simple blood test from participants and the information will be added to bio banks.
- The project will aim to make predictive diagnostic markers available for some priority diseases such as cancer and other rare and genetic disorders.
- The department has also initiated an outreach programme to provide genetic diagnosis and counselling to families affected by common genetic disorders in certain districts.
What is Gene Sequencing?
- A genome is the DNA or sequence of genes in a cell.
- Most of the DNA is in the nucleus and intricately coiled into a structure called the chromosome.
- Every human cell contains a pair of chromosomes, each of which has three billion base pairs or one of four molecules that pair in precise ways
- The order of base pairs and varying lengths of these sequences constitute the “genes”.
- Sequencing a genome means deciphering the exact order of base pairs in an individual.
- It has been known that the portion of the genes responsible for making proteins called the exome occupies about 1% of the actual gene.
- The genome has to be mapped in its entirety to know which genes of a person’s DNA are “mutated”.
- Golden Rice is a new type of rice that contains beta-carotene (provitamin A), which is converted into vitamin A as needed by the body and gives the grain its golden color.
- It is developed through genetic engineering and produces two new enzymes that complete the beta-carotene expression in the rice grain.
- Research has indicated that one cup of Golden Rice can provide up to 50% of the daily requirement of an adult for vitamin A.
- But presently, it has a low shelf life of not more than 3 months as it may lose its nutrients after that.
- Golden Rice can be grown just like ordinary rice and varieties containing the GR2E Golden Rice trait have the same yield and agronomic performance as their conventional counterparts.
- It is intended to complement current strategies in the fight against vitamin A deficiency (VAD) and is intended to supply up to 30-50 percent of the estimated average requirement for vitamin A for preschool age children and pregnant or lactating mothers.
Vitamin A Deficiency (VAD)
- Vitamin A is a fat-soluble vitamin that is good for healthy vision, skin, bones and other tissues in the body.
- Source: There are two types of vitamin A.
- Preformed vitamin A, also called retinol, is found in animal products. Good sources are fortified milk, eggs, meat, cheese, liver, halibut fish oil, cream and kidneys.
- Pro-vitamin A is found in plant-based foods such as fruits and vegetables. The most common type of pro-vitamin A is beta-carotene, a carotenoid that produces dark pigments in plant foods.
- As vitamin A affects a wide range of body functions, a deficiency can lead to a variety of problems. These include:
- night blindness
- a higher risk of infections, especially in the throat, chest, and abdomen
- follicular hyperkeratosis, leading to dry, bumpy skin.
- fertility issues
- delayed growth in children
International Rice Research Institute (IRRI)
- IRRI is an independent, non-profit, research and educational institute, founded in 1960 by the Ford and Rockefeller Foundations with support from the Philippine government.
- The institute, headquartered in Los Baños, Philippines, has offices in 17 rice-growing countries in Asia and Africa.
- It is the world’s premier research organization dedicated to reducing poverty and hunger through rice science; improving the health and welfare of rice farmers and consumers; and protecting the rice-growing environment for future generations.
INDIAN COBRA GENOME SEQUENCED
An international team of researchers have sequenced the genome of the Indian cobra, in the process identifying the genes that define its venom.
What is the significance?
- This genome sequence can provide a blueprint for developing more effective anti-venom.
- The cobra genome sequence is of really high quality.
- Sequence information of the genes that code for venom proteins is very important for the production of recombinant anti-venoms.
Are existing anti-venoms not effective enough?
- Their efficacy varies, besides producing side effects.
- In India, the challenge has
been producing anti-venom for the species known collectively as the “big
- The Indian cobra (Naja naja),
- Common krait (Bungarus caeruleus),
- Russell’s viper (Daboia russelii), and
- Saw-scaled viper (Echis carinatus).
- Common anti-venom is marketed for the treatment of bites from the “big four”, but its effectiveness came under question in a recent study.
- The common anti-venom worked against the saw-scaled viper and the common cobra.
- But this anti-venom fell short against some neglected species and also against one of the “big four” – the common krait.
- Facts – Accidental contacts with snakes lead to over 100,000 deaths across the world every year.
- India alone accounts for about 50,000 deaths annually, and these are primarily attributed to the “big four”.
Why has production of effective anti-venom been challenging?
- Venom is a complex mixture of an estimated 140-odd protein or peptides.
- Only some of these constituents are toxins that cause the physiological symptoms seen after snakebite.
- But anti-venom available today does not target these toxins specifically.
- Anti-venom is currently produced by a century-old process.
- In this process, a small amount of venom is injected into a horse or sheep, which produces antibodies that are then collected and developed into anti-venom.
What are the issues with this ‘horse technique’?
- This is expensive, cumbersome technique and comes with complications.
- Some of the antibodies raised from the horse may be completely irrelevant.
- The horse also has a lot of antibodies floating in its blood that have nothing to do with the venom toxins.
- One more problem with horse antibodies is that our immune system recognises it as foreign and when anti-venom is given our body mounts an antibody response. This leads to what is called serum sickness.
How does decoding the genome help?
- In the Indian cobra genome, the researchers have identified 19 key toxin genes, the only ones that should matter in snakebite treatment.
- They stress the need to leverage this knowledge for creation of safe and effective anti-venom using synthetic human antibodies.
- The next step would be obtaining the genomes and the venom gland genes from the other three of the “big four” and the deadly African species.
- However, there is a very long way to go from genomes to effective anti-snake venoms.
- It is world’s first patented heterogeneous catalytic process which converts multiple feed stocks into hydrocarbon liquid fuels, gas, carbon and water.
- The process is a closed-loop system and does not emit any hazardous pollutants into the atmosphere.
- Polycrack Plant can be fed with all types of plastic, petroleum sludge, un-segregated MSW (Municipal Solid Waste) with moisture up to 50%, e–waste, automobile fluff, organic waste including bamboo, garden waste etc., and Jatropha fruit and palm bunch.
How it works?
- The process is a closed-loop system and does not emit any hazardous pollutants into the atmosphere.
- The combustible, non-condensed gases are re-used for providing energy to the entire system and thus, the only emission comes from the combustion of gaseous fuels.
- The emissions from the combustion are found to be much less than prescribed environmental norms.
- This process will produce energy in the form of Light Diesel Oil which is used to light furnaces.
Advantages of Polycrack
Polycrack has the following advantages over the conventional approach of treating solid waste:
- Pre-segregation of waste is not required to reform the waste. Waste as collected can be directly fed into Polycrack.
- It has high tolerance to moisture hence drying of waste is not required.
- Waste is processed and reformed within 24 hours.
- It is an enclosed unit hence the working environment is dust free.
- Excellent air quality surrounding the plant.
- Biological decomposition is not allowed as the Waste is treated as it is received.
- The foot print of the plant is small hence the area required for installing the plant is less when compared with conventional method of processing.
- All constituents are converted into valuable energy thereby making it Zero Discharge Process.
- Gas generated in the process is re-used to provide energy to the system thereby making it self-reliant and also bring down the operating cost.
- There is no atmospheric emission during the process unlike other conventional methods except for combustion gases which have pollutants less than the prescribed norms the world over.
- Operates around 450 degrees, making it a low temperature process when compared with other options.
- Safe and efficient system with built-in safety features enables even an unskilled user to operate the machine with ease.
- Low capital cost and low operating cost.
- Fully automated system requires minimum man power.
- Food irradiation is a technology in which food products are subjected to a low dosage of radiation to treat them for germs and insects, increasing their longevity and shelf life.
- It is the application of ionizing radiation to food in which energy is transmitted without direct contact in the targeted food.
- The radiation can be emitted by a radioactive substance or generated electrically.
- The irradiated food does not become radioactive.
- Radioisotopes are used as the source for the gamma rays.
- Generally cobalt-60 radioisotope is used as a radioactive source for gamma irradiation.
- International Atomic Energy Agency (IAEA) recommends the irradiation doses for Food irradiation.
- Irradiation is equivalent to pasteurization for solid foods, but it is not the same as sterilization.
- It does not reduce the nutritional value of food products and does not change their organoleptic properties and appearance.
- The irradiation treatment of food and food grains preserves them for longer time, prevent the spread of invasive pests, delay/eliminate ripening or sprouting and reduce the risk of food borne illness.
BHARATIYA POSHAN KRISHI KOSH
The Union Minister of Women and Child Development (WCD) and Textiles along with Bill Gates, co-chair of Bill & Melinda Gates Foundation launched the Bharatiya Poshan Krishi Kosh (BPKK)
- The BPKK will be a repository of diverse crops across 128 agro-climatic zones in India for better nutritional outcomes.
- At the request of the Ministry of WCD, the Harvard Chan School of Public Health through its India Research Center and the Bill and Melinda Gates Foundation will document and evaluate promising regional dietary practices and the messaging around them and develop a food atlas on regional agro-food systems. Both efforts are aimed at mobilizing the diverse sectors of the society.
- In consultation with the Ministry of WCD and Bill & Melinda Gates Foundation, the project team will select around 12 high focus states which are representative of the geographical, social, economic, cultural and structural diversities of India.
- In each of the states or group of states, the team will identify a local partner organization which has relevant work experience in Social and Behavior Change Communication (SBCC) and nutrition for developing the food atlas.
MUKTOSHRI ARSENIC-RESISTANT RICE
West Bengal government’s rice research centre has come up with a new variety of rice called Muktoshri that can be grown in arsenic prone areas. It was developed jointly by the Rice Research Station at Chinsurah, coming under West Bengal’s Agriculture Department and the National Botanical Research Institute, Lucknow.
West Bengal has a high concentration of arsenic in groundwater, with 83 blocks across seven districts having higher arsenic levels than permissible limits.
Arsenic- Key facts:
Arsenic is naturally present at high levels in the groundwater of a number of countries. It is also present in rocks and soils.
Arsenic is highly toxic in its inorganic form.
World Health Organization’s provisional guideline value for arsenic in drinking water is 0.01 mg/l (10 μg/l). The permissible limit of arsenic in India in the absence of an alternative source is 0.05 mg/l (50 μg/l).
- Contaminated water used for drinking, food preparation and irrigation of food crops poses the greatest threat to public health from arsenic.
- Long-term exposure to arsenic from drinking-water and food can cause cancer and skin lesions.
- It has also been associated with cardiovascular disease and diabetes.
- In utero and early childhood exposure has been linked to negative impacts on cognitive development and increased deaths in young adults.
What’s the difference between organic arsenic and inorganic arsenic?
Atoms of arsenic bond with other elements to form molecules — if carbon is one of these elements, then the arsenic compound is an organic compound. If there is no carbon present, then the arsenic compound is in an inorganic compound.
Inorganic arsenic is a known human carcinogen — it is this form of arsenic that is linked with increased risks of cancer and other health effects.
GENOME SEQUENCING OF BASMATI RICE
The complete genome of two basmati rice varieties, including one that is drought-tolerant and resistant to bacterial disease, has been mapped by scientists.
- In 2016, the Agricultural and Processed Food Products Export Development Authority (APEDA) registered Basmati Rice as a product with Geographical Indication (GI).
- According to APEDA, a rice variety is eligible to be notified as Basmati if it has a minimum average precooked milled rice length of 6.61 mm and average precooked milled rice breadth of up to 2 mm, among other parameters.
Conditions for Rice cultivation:
- Temperature: Between 22-32°C with high humidity.
- Rainfall: Around 150-300 cm.
- Soil Type: Deep clayey and loamy soil.
- Top Rice Producing States: West Bengal > Punjab > Uttar Pradesh > Andhra Pradesh > Bihar.
- India is the second-largest producer of rice in the world after China.
- In Assam, West Bengal and Odisha, three crops of paddy are grown in a year. These are Aus, Aman and Boro.
- National Food Security Mission, Hybrid Rice Seed Production and Rashtriya Krishi Vikas Yojana are few government initiatives to support rice cultivation.
- As per the findings, basmati rice is a hybrid of two other rice groups.
- The researchers focused on two basmati rice varieties: Basmati 334 from Pakistan, known to be drought tolerant and resistant to rice-killing bacterial blight, and Dom Sufid from Iran, aromatic long-grain rice that is one of the most expensive on the market.
- The most genetic material in basmati comes from japonica —a rice group found in East Asia — followed by the rice group aus found in Bangladesh.
A team from the National Centre for Biological Sciences (NCBS), Bengaluru, has found that the rich colour in fruits and leaves of plants are indirectly controlled by specific micro RNAs, miR828 and miR858.
What is microRNA?
- A microRNA, also known as miRNA is a small non-coding Ribonucleic acid (RNA) molecule containing about 22 nucleotides.
- It is found in plants, animals and some viruses that functions in RNA silencing and post-transcriptional regulation of gene expression.
- miRNAs function via base-pairing with complementary sequences within mRNA molecules.
- As a result, these mRNA molecules are silenced, by one or more of the following processes
Cleavage of the mRNA strand into two pieces.
- Destabilization of the mRNA through shortening of its poly(A) tail.
- Less efficient translation of the mRNA into proteins by ribosomes.
How micro RNAs regulate the colour of fruits, leaves?
- Grape plants bear fruits having colours that can be deep purple or green.
- This colour is due to compounds called anthocyanins and flavonols, both of which are present in grape fruits.
- When the grape plant has a high amount of anthocyanin as compared to flavonol, the fruits are deep purple.
- When the reverse is true, the grapes are not brightly coloured.
- The relative abundance of anthocyanin and flavonol is controlled by genes known as the MYB transcription factors.
- They are also referred to as activators.
- When present in large amounts, they result in dark purple grape, as in the Bangalore Blue variety, and absence correlates with lack of bright colour but high incidence of flavonols as in the Dilkhush grape variety.
- Micro RNAs are regulators of gene expression, acting like switches.
- They decide which protein should be made and how much in a given cell or tissue or an organism.
- They are tiny, having some 20 to 22 digits of RNA.
- The miRNA inhibit target RNAs by cutting them into two bits in plants.
- The miRNAs partner with a protein called Argonaute to do this regulation.
- Bio fortification is the process by which the nutritional quality of food crops is improved through agronomic practices, conventional plant breeding, or modern biotechnology.
- Plants having anthocyanin and flavonol can be generated by controlling the microRNAs affecting them,which can be used in biofortification.
Recently, the World Health Organization (WHO) in a report held that Vaccine hesitancy is among the top 10 threats to global health in 2019.
WHO defines Vaccine hesitancy as a delay in acceptance or refusal of vaccines despite the availability of vaccination services. Vaccine hesitancy has been reported in more than 90% of countries in the world.
Instances of Vaccine Hesitancy
- Globally nearly 4,24,000 children have confirmed measles in 2019, as against a figure of 1,73,000 in the whole of 2018.
- In India, poor communities of Uttar Pradesh was reported to have taken five times low uptake of oral polio vaccine in the early 2000s.
Reasons for Vaccine Hesitancy
The main issue with Vaccine hesitancy is misinformation.
- Religious propaganda that the vaccine may contain microbes, chemicals and animal-derived products which is forbidden by religious laws.
- Social media is used in stirring fear in people by falsely blaming vaccines for unrelated diseases is the bedrock of the Vaccine hesitancy all across the globe.
- For example, recently some sections in India are refraining from the polio vaccine. This is due to the misconception that the polio vaccine caused illness, infertility and was ineffective.
- Vaccine-derived diseases: Oral Polio Vaccines (OPV) contains weakened but live poliovirus. This virus from the vaccine is excreted by immunized children which can move from one person to another.
- This allows the virus to stick around and mutate to a more virulent form, raising the threat of vaccine-derived poliovirus (VDPV).
- Inconvenience in accessing vaccines is also the leading cause of Vaccine hesitancy.