1. Antibiotic resistance
  2. Super-spreading of Dengue
  3. Humanised mice
  4. RNTCP (Revised National TB Control Programme)
  5. Reproduction
  6. Spicy food and Tears
  7. G-protein–coupled receptors (GPCRs)
  8. Pineapple itching
  9. Blank Slate Cells / Reprograming Cells / Disease in Dish
  10. ENCODE project
  11. Single-dose drug cure for malaria
  12. HIV drops in India
  13. Linear No Threshold (LNT) concept
  14. Tobacco law & WTO
  15. Mock Questions
  16. Mains/Descriptive

Antibiotic resistance

  • It is the ability of certain microorganisms to withstand attack by antimicrobials drugs
  • Main factor for the rise and spread of resistant microbes= Overuse and misuse of antimicrobials drugs.
  • The spread of drug resistance is faster in India due to many reasons — lack of infection control practices in hospitals, absence of antibiotic policy, sanitation issues in the community etc.

Super-spreading of Dengue

  • Super spreading means, one infected person passes on a disease to lots of others,
  • This is an important factor driving dengue transmission in places.
  • Since mosquitoes are concentrated in only a couple of homes in each locality, an infected individual in those houses or in their immediate vicinity was likely to get bitten and pass on the virus to a large number of mosquitoes, who then pass it on to many other humans
  • mosquito Aedes aegypti carries the virus for Dengue.

Humanised mice

  • It is engrafted with human liver cells.
  • It’ll help research liver-to-blood stage infection of Malaria.
Why Humanized Mice? (Click to Enlarge)

RNTCP (Revised National TB Control Programme)

  • Meant for 2012-2017
  • It aims to involve private sector into the fight against Tuberculosis.
  • Nearly one lakh new multidrug resistant (MDR) TB cases are estimated to occur every year.
  • The only way of reducing mortality and morbidity is by engaging the private sector

Reproduction

Q. Why does the immune system in females not attack sperms (foreign bodies) that enter the female body?

  • human immune system is that it can differentiate ‘self’ from ‘others.’ This allows the body to fight off any foreign cells which it encounters. That is why it is difficult to transplant organs without suppressing the immune system
  • However, when it comes to reproduction, the human body not only ignores the sperm, but also fails to recognise the foetus (which has half of its material from a ‘foreign’ donor) as a foreign body
  • Studies have confirmed the presence of markers on the surface of the human sperm
  • These markers on the sperm are universally recognised by any woman’s immune system, and trick the immune system into believing that the sperm is harmless. That is why reproduction can occur between any two people.

Spicy food and Tears

  • Why are tears produced in our eyes when we eat something which is spicy or spicy over our limits?
  • When we eat food the sensory nerve endings on our tongue are stimulated.
  • This nerve also serves as the sensory nerve to the surface of the eye and face.
  • When we eat very spicy food the sensory nerve endings on the tongue are irritated and an overload of noxious stimulus is carried to the eyes as well, hence tears.

G-protein–coupled receptors (GPCRs)

  • Human cells have these receptors
  • It enables them to sense chemical substances — hormones, poisons and drugs — in their environment.
  • 2012 Noble Prize in Chemistry is given for this topic.

Pineapple itching

  • Why do we get an itching sensation in our mouth when we eat too much of pineapple?
  • Pineapple, botanically, is not a single fruit berry. It is a collection of individual fruits (each fruit, marked on the surface by the near-hexagonal demarcation)
  • Pineapple contains a proteolytic (protein hydrolyzing) enzyme
  • When we have eaten the pineapple, this enzyme temporarily stays on the tongue and interiors of the mouth and starts attacking the proteinous muscle parts of the tongue and the mouth while sensitizing the nerve endings there.
  • These neurological signals, when transmitted to the brain, make us feel the pricking and itching sensation.

Blank Slate Cells / Reprograming Cells / Disease in Dish

  • Terms associated with stem cell research done by Gurdon and Yamanaka (they got Noble-2012 for it).
  • Once created, these “blank slate” cells can be used for developing into other cell types.
  • For example, Skin cells can ultimately be transformed into brain cells.
  • This Reprogramming allows scientists to create particular kinds of tissue they want to study, like lung tissue for studying cystic fibrosis, or brain tissue for Huntington’s disease.
  • By reprogramming cells from patients with a particular disease, they can create new tissue with the same genetic background, and study it in the lab. That can give new insights into the roots of the problem.
  • In addition, that approach allows them to screen drugs in the lab for possible new medicines.
  • (more discussed in earlier guest article by Mr.Manikandan)

ENCODE project

  • ENCyclopedia Of DNA Elements, which was started in 2003.
  • The goal is to find all functional elements in the human genome.
  • Until recently, the majority view has been that much of the DNA is “junk”—DNA that is never transcribed and has no biological function and only 1% of the DNA is actually responsible for everything.
  • But ENCODE project has found that not one per cent but more than 80 per cent of the genome has an active role or function.

Single-dose drug cure for malaria

  • Scientists claim to have discovered a drug that could cure all strains of malaria with a single oral dose and also block transmission of the deadly parasite from person to person.
  • Will be made from synthetic molecule from the aminopyridine class.

HIV drops in India

  • HIV — which causes AIDS — was detected in India nearly 25 years back. Though more than 2 million people are affected by the virus, India is said to be one of the few countries which has actually made significant reductions in HIV infections.
  • India had witnessed a sharp decline in the number of new HIV cases — a 56 per cent drop — in the past 10 years, because of the National AIDS control Programme.
  • Antiretroviral therapy (ART) =Used for HIV treatment.

Linear No Threshold (LNT) concept

  • means that harmful effects of radiation increase with radiation dose and even small radiation doses can cause some finite harm.
  • Some scientists challenge the validity of LNT concept.
  • They say, in low dose radiation we would be fine, and would not have any cellular damage.
  • (then it leads to debate on mobile phone radiation etc. we already saw it in an earlier article.)

Tobacco law & WTO

  • Australia enacted world’s toughest law on cigarette promotion, meaning tobacco companies will be prohibited from displaying their logos on cigarette packs that will instead feature images of cancer—riddled mouths, blinded eyeballs and sickly children.
  • But Australia faces a potential challenge to its laws through the World Trade Organization,
  • Three tobacco growing countries Ukraine, Honduras and the Dominican Republic making official requests for consultation on plain packaging.
  • Consultations are the first stage of the WTO’s dispute resolution process.

Mock Questions

Which of the following statements are correct?

  1. Aedes aegypti carries the virus for Dengue.
  2. India launched national antibiotic policy in 2007
  3. Pineapple  is a single fruit berry.

Mains/Descriptive

  1. What are the salient features of National Aids Control Programme. Evaluate its success. What steps should be taken in future, to reduce the spread of HIV even further? (25m)
  2. Write a note on the Revised National TB Control Programme (10m)
  3. Examine the need for a National policy on Antibiotics? 10 marks
  4. Examine the ethical issues involved in Stem cell research. What is the policy of Government of India, regarding Stem cell research?

Ref:
The Hindu, S&T section, September-October 2012