Viruses
H7N9
- avian flu virus.
- currently in some regions in China.
- H7N9, H1N1 and H5N1= All three viruses are influenza A viruses
- but they are distinct from each other.
- H7N9 and H5N1 are considered animal influenza viruses that sometimes infect people.
- while H1N1 viruses can be divided into those that normally infect people and those that normally infect animals.
- Influenza viruses are not transmitted through consuming well-cooked food. Because influenza viruses are inactivated by normal temperatures used for cooking.
- It is safe to eat properly prepared and cooked meat, including from poultry and game birds.
- But Diseased animals and animals that have died of diseases should not be eaten.
- No vaccine for H7N9 available at the moment.
- An animal influenza virus that develops the ability to infect people could theoretically carry a risk of causing a pandemic.
- However, whether H7N9 virus could actually cause a pandemic= still unknown.
H3N2
- The H7N9 bird flu virus has been sporadically infecting people in China, Some experts fear it could gain the ability to spread easily among humans, thus setting off another influenza pandemic like H1N1 pandemic of 2009.
- But American researchers have found a possible threat from a different direction — H3N2
- H3N2 viruses are currently found in birds and pigs.
- A H3N2 virus caused a pandemic during 1967-68, but now scientist fear that human immune system might have lost the ability to recognize that virus and thus H3N2 could easily jump back to humans now that immunity to it has dropped
SARS like Coronavirus
- 2002: SARS (‘severe acute respiratory syndrome’) appeared in China and next year exploded across the world. SARS was caused by a coronavirus.
- 2012: Another coronavirus (hCoV-EMC), emerged in Middle East, causing severe respiratory problems, kidney failure and even death.
- As with the SARS virus, the new hCoV-EMC coronavirus appears to have originated in bats. However, unlike the former, the latter is still able to infect bat cells.
Drug research
Influenza Vaccine
- Presently, the scientists are ill-equipped to immediately develop an effective vaccine when an influenza virus strikes. for e.g. when the H1N1 pandemic struck in 2009.
- Current strategy for vaccine Development = start from scratch based on the strain causing the epidemic or pandemic = takes lot of time.
- Now American researchers are using a new strategy for vaccine Development.
- They selected F16 (an antibody to influenza A), and introduced it into an adeno-associated virus (AAV) vector to deliver the antibody into the body.
- To achieve the best results, the researchers introduced the antibody at the site of infection, in this case, the nasal route.
- This will be equally effective against influenza strains — H5N1 and H1N1.
Monoclonal antibody: curing blood cancer
- Leukaemia is largely incurable in adults. Why?
- Because the cancer-associated proteins are safely secured inside cells, and are beyond the reach of currently available drugs.
- now scientists are developing a new monoclonal antibody (ESK1) that can target those cancer-associated proteins.
- more on monoclonal antibodies covered here click me
Gold nanoparticles for drug delivery
- gold nanoparticles can be used as carriers for delivering anti-cancer drugs and also for diagnosing the disease, particularly lung and breast cancer
- In Ayurveda. More than 1,000 years ago, gold was used as a nanoparticle (swarnabhasma).
- At that time, there were no sophisticated instruments and that is why people did not know that it was a gold nanoparticle.
- gold nanoparticle was bio-compatible, easy to synthesize and multiple cancer drugs could be loaded. It could reduce the toxicity of the anti-cancer drug,
- Scientists are now using an eco-friendly green chemistry approach- via leaf extracts of Bhringaraj (a herbal plant) to create the biocompatible nanoparticles.
- Bhringaraj-extracted bio-compatible gold nanoparticle was used to deliver an anti-cancer drug —Doxorubicin into lung and breast cancer cell lines.
- If you add fluorescent molecule in these gold nanoparticles, it could be used to detect the position of the tumor.
ELQ-300 new Antimalarial drug
- nearly 200 million people in the world suffer from malaria every year, and the mortality is as high as 1.2 million. To make matters worse, resistance to currently available drugs is emerging.
- ELQ-300 is a new anti-malarial drug, undergoing trials.
- capable of treating and preventing malaria infection, target both the liver and blood stages.
- works against both drug-resistant species (Plasmodium falciparum and Plasmodium vivax).
- Schizont is a matured malaria parasite that contains many merozoites, which is the parasite stage that infects red blood cells. ELQ-300 was effective against this Schizont.
Induced pluripotent stem cells (iPSC)
Stem cell controversy?
- Stem cells can be used in treating variety of diseases.
- But they were sourced from human embryos in the beginning.
- Religious organizations consider this as murdering a child and hence oppose stem cell research.
Nobel 2012: solution for stem cell harvesting?
- 2012: Nobel prize for medicine given to John B. Gurdon and Shina Yamanaka
- for their discovery that discovery that differentiation of cells is a reversible process.
- In other words, normal cells can be reconverted into stem cells. and then those stem cells could be used for treatment of various diseases.
- thus, Gurdon and Yamanaka’s research could settle the stem cell controversy (because we don’t need human embryos for harvesting stem cells anymore. We can do it by converting normal cells into stem cells.)
Induced pluripotent stem cells (iPSC)?
- iPSCs are body (somatic) cells which have been reprogrammed to function like embryonic stem cells
- This is done by introducing four regulatory factors (pieces of DNA) into the cells.
- However, the efficiency of iPSC production is traditionally quite low. Only about 0.01 per cent of the cells successfully become iPSC.
- Chinese researchers are now working to improve this performance.
Zebrafish zygote
- Zygote is the initial cell formed when two gamete cells (from male and female) are joined
- zygote is special because this single cell is capable of developing into an embryo and ultimately an entire organism, unlike an already-differentiated cell like a skin cell which can only develop into skin tissue. This property of the zygote is called ‘totipotency’.
- embryo cell=undifferentiated cell the embryo cell
- egg cell and the sperm cell= differentiated cells
- Diseases like cancer cause cells that get arrested at an early stage of differentiation, or cells that go backwards and become undifferentiated like embryo cells.
- Scientists carried out research on Zebrafish eggs to understand this mechanism of totipotency.
Equipment/ devices
3Nethra: eye testing device
- The World Health Organization estimates that 39 million people in the world are blind. Of those, over 15 million are in India.
- Most of that blindness can actually be prevented.
- But people do not realise they have an eye disease and that they are losing their vision because their better eye compensates for the loss in one eye.
- solution = conduct regular eye tests.
- Problem= only 15,000 eyedoctors in India and only ~30 per cent of them practice in the rural areas.
- + conducting mass eye tests in remote locations is difficult because the traditional equipment for eye tests are bulky and expensive.
- here 3Nethra comes to help
What is 3Nethra?
- a portable and less expensive pre-screening device for eyes
- 3nethra can fit into a suitcase and weighs about 15 kg= lighter than traditional equipment.
- costs ~ five lakh rupees = cheaper than traditional equipment.
it takes a picture of the eye and can detect the five major ailments that lead to 90% of blindness.
- diabetic retinopathy,
- cataract,
- glaucoma,
- cornea problems
- refractive errors.
- The machine is also non-mydriatic (does not need dilation of the pupil) and can take images in a matter of minutes.
- doesn’t require highly trained ophthalmologist, even a semi-skilled person with a working knowledge of the anatomy of the eye can operate this machine.
Eye-PAC computing technology
- by IIT Madras
- It is based on the principle of capturing the image of the eye, digitising it before transferring the information to a computing system.
- The technology teases out specific information from the images and provides a computer-assisted screening decision
- technology can process the image obtained without dilating the eye, thus saving time both for the operator and patient.
- When used as a diagnostic solution, the computer-assisted decision saves the ophthalmologists’ time
- This technology has been used in the 3Nethra device we saw earlier.
Cholangioscope
- pancreatic cancer is the third most prevalent gastro-intestinal cancer in India while liver cancer is the most common.
- All these years, most patients used to consult a physician when the disease was in an advanced stage.
- cholangioscope is an equipment with a video camera for detection of cancers of bile duct, liver and pancreas.
- jointly developed by by Indian and Japanese healthcare researchers.
- another latest device, called ‘spycam,’ was now enabling doctors to look into the liver, which was not possible earlier.
- the two technologies would help in diagnosis and treatment of gall bladder stones, jaundice, pancreatitis and pancreatic pain. Very huge stones could be identified and crushed using laser.
E-cigarette
- Cigarette lighting up and burning leads to smoke. And the smoke is a health hazard. It produces carbon monoxide (CO), a blood poison, nitrogen oxides (which can destroy molecules in the body), and the tar produced during incomplete burning (it is the tar which is the major cancer-culprit).
- Smoke is not only bad for the user, but also for the bystander- through what is called secondary smoking
- In an electronic cigarette, you do not light up and produce smoke.
- You do not even use tobacco. You take nicotine (the addictive), dissolve it in glycols (which are acceptable to the human body) and using an electronic method, produce an aerosol mist and inhale the vapour.
- There is no smoke, no Carbon Monoxide, no nitrous mix, no tar, no yellow teeth.
- They are better than the nicotine patch or gum; and they can help smokers quit. (atleast that what the companies claim)
LED’s effect on sleep
- Modern light-emitting diodes (LEDs) used in energy-efficient lighting as well as television and computer screens, laptops, tablets and various handheld devices.
- electric light has had a powerful impact on the body’s clock, known as the circadian rhythm.
- light affects our circadian rhythms more powerfully than any drug.
- eye’s retina also contains light-sensitive cells help synchronise the body’s circadian rhythm to the natural day and night cycle.
- When artificial light strikes those cells, the body gets misled and responds by promoting wakefulness and inhibiting sleep.
- many people are still checking e-mail, doing homework or watching TV at midnight, with hardly a clue that it is the middle of the solar night, driving us to go to bed later.
- Children become hyperactive rather than sleepy when they don’t get enough sleep, and have difficulty focusing attention, so sleep deficiency may be mistaken for attention-deficit hyperactivity disorder (ADHD), an increasingly common condition now diagnosed in American teenagers.
Gene patenting, BRCA, Angelina Jolie
Gene Patenting case
- BRCA1 and BRCA2 human genes used for diagnosing breast and ovarian cancers. (BRCA= BReast CAncer). If a woman has mutation (fault) in BRCA 1 or 2= higher risk of breast/ovarian cancer.
- U.S. Patent and Trademark Office has been awarding patents on genes for about 30 years.
- In the mid-90s, Myriad Genetics ltd. got patents for the BRCA genes.
- Thanks to this patent, Myriad genetics company got monopoly for selling BRCA gene testing. Each test costs >3000$.
- 2009-10: The American Civil Liberties Union (an NGO) challenged this patent in court. Their point= Nobody can “patent” human genes because genes are products of nature.
- 2013: Matter going in US Supreme Court.
Angelina Jolie’ double mastectomy
- Angelina Jolie had a “faulty” gene, BRCA1=> had higher risk of getting breast cancer.
- Doctors advised her to undergo a surgery known as “preventive double mastectomy”, to remove her breasts and hence reduce the risk of getting Brest cancer in future.
- she got that surgery in 2013, and also wrote an article about her experience in New York Times (click me)
Conspiracy/criticism
- A gene patent holder has the right to prevent anyone from studying, testing or even looking at a gene. As a result, scientific research and genetic testing has been delayed, limited or even shut down due to concerns about gene patents.
- Only Myriad can sell BRCA gene test, which gives them a monopoly on a highly profitable business.
- Angelina Jolie’s move was a mere PR/marketing campaign for Myriad genetics, with inflated statistics.
- Now Many women will now take that expensive BRCA testing (for >3000$) undergo the surgery just out of fear and panic, because Jolie opted for it. And thus Myriad Company will make truckload of cash for holding patents to BRCA genes.
- President’s Obama’s “Affordable Care Act” mandates taxpayers to pay for BRCA1 genetic testing- thus increasing Myriad’s profit even further.
- BRCA is not the only gene patented, some other companies and universities also have patented genes for Tay-Sachs disease, Cystic fibrosis, Colorectal cancer, Hearing loss etc. at this rate, future medical treatments will become prohibitively expensive. Therefore, the whole idea of Gene Patenting is against the interest of patients.
Oily Skin
- Why is skin oiliness restricted only to the face?
- skin of the face is oily because of the presence of sebum
- Sebum is an oily secretion produced by the sebaceous gland.
- These glands are present throughout the body except the palms of hand and soles of feet.
- Sebaceous glands are more commonly found in hair-covered areas, where they are connected to hair follicles.
- Hence the maximum concentration of this sebaceous gland is in the face and scalp.
- Acne and black heads are conditions associated with these sebaceous glands and they are common in face.
factors
- secretion of the gland is influenced by the sex hormones, temperature, stress and genetic factors.
- Sebum production increased during adolescence, pregnancy and menopause due to hormonal changes.
Function of Sebum?
- provides anti- bacterial lipids, anti- oxidants,
- hydrates the superficial layers of skin, supply of vitamin E
- also has temperature regulation properties.
Mock Questions at the end of third part. For more on science-tech, visit Mrunal.org/snt
sir,do we need to prepare haelth related affairs for mains?it has been removed from syllabus.it is there only for prelims.please tell me?awaiting anxiously for your reply.
“Issues relating to development and management of Social Sector/Services relating to Health,
Education, Human Resources.”
So health related affairs esp. govt schemes are still important.
Sir u simply are awesme!!
Hi,
Anyone got UP PCS Pre admit card ?
you can download after 16 june
Hello,
Shall be grateful if you could return to your original style of quality(in terms of conciseness & lucidity) over quantity.
Many of us readers are baffled over the dramatic sea change in topics taken & content presented.
Hope you revert to your old issue-based blogs. Waiting eagerly for it!!! :)
Thanks a ton in advance!
Hey guys! do we still need to prepare those FIRST-AID portions.
Link of
more on monoclonal antibodies covered here click me
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Wow that was unusual. I just wrote an extremely long comment but after I clicked submit my comment didn’t show up. Grrrr… well I’m not writing all that over again. Anyhow, just wanted to say superb blog!