Some Qs. people asked me on science and my replies to them - Part 67

                                                              Interactive science series

Q: What is a virulence  factor?

Krishna: Virulence factors are molecules synthesized by micro-organisms like viruses, bacteria, fungi and protozoa to become more effective in causing a disease in their host. This is done in several ways. 

• colonization of a niche in the host - this includes attachment to cells by using sticky molecules for attachment. For example many bacteria use adhesins, a surface protein, to remain attached to the host cell.
• immunoevasion, evasion of the host's immune response - by using tough structures. For example capsules help many pathogenic bacteria to survive phagocytosis (the ingestion of bacteria or other material by phagocytes).
• immunosuppression, i.e., inhibition of the host's immune response - some bacteria use enzymes like immunoglobin proteases to break down antibodies.
• entry into and exit out of cells (if the pathogen is an intracellular one)
• obtain nutrition from the host

 Some bacteria, such as Streptococcus pyogenes, Staphylococcus aureus and Pseudomonas aeruginosa, produce a variety of enzymes which cause damage to host tissues. Enzymes include hyaluronidase, which breaks down the connective tissue component hyaluronic acid; a range of proteases and lipases; DNases, which break down DNA, and hemolysins which break down a variety of host cells, including red blood cells. Virulence Factors basically Include the Antigenic Structure and The Toxins produced by the organisms.

A major group of virulence factors are bacterial toxins. These are divided into two groups: endotoxins and exotoxins.

Endotoxins trigger intense inflammation. They bind to receptors on monocytes causing the release of inflammatory mediators which induce degranulation. As part of this immune response cytokines are released; these can cause the fever and other symptoms seen during disease. If a high amount of LPS is present then septic shock (or endotoxic shock) may result which, in severe cases, can lead to death. Endotoxins are non-immunogenic, and therefore do not have an acquired immune response.
Exotoxins are actively secreted by some bacteria and have a wide range of effects including inhibition of certain biochemical pathways in the host. The two most potent known exotoxins[2] are the tetanus toxin (tetanospasmin) secreted by Clostridium tetani and the botulinum toxin secreted by Clostridium botulinum. Exotoxins are also produced by a range of other bacteria including Escherichia coli; Vibrio cholerae (causative agent of cholera); Clostridium perfringens (common causative agent of food poisoning as well as gas gangrene) and Clostridium difficile (causative agent of pseudomembranous colitis). A potent three-protein virulence factor produced by Bacillus anthracis, called anthrax toxin, plays a key role in anthrax pathogenesis. Exotoxins are extremely immunogenic meaning that they trigger the humoral response (antibodies target the toxin).

Exotoxins are also produced by some fungi as a competitive resource. The toxins, named mycotoxins, deter other organisms from consuming the food colonised by the fungi. As with bacterial toxins, there is a wide array of fungal toxins. Arguably one of the more dangerous mycotoxins is aflatoxin produced by certain species of the genus Aspergillus (notably A. flavus). If ingested repeatedly, this toxin can cause serious liver damage.

Q: You answer others' questions. Who will answer your questions?

Krishna: Great! I felt like answering this question. This is mischievous! And I loved it!

I only put questions to myself  to find out new things and fact -filled innovative answers.

I just wanted to remove misconceptions, irrational and baseless beliefs, negate pseudo-science, educate people and show them a new wave of thought process. That is why I answer these questions people ask me. But I am honored to find out even some scientists and professors are asking me questions!

Some admire my answers, some condemn. Who cares?!

But I know I am different from several others. And the world progresses because of the people who have the courage to think and go differently.

Anyone cares to follow me?! :)

Q: What do you think of the people who are spreading pseudoscience and other misinformation such as science is a Western ideology? Shouldn't such people be kicked out of civilized societies?  

Krishna: In democracies, they say, people have the right to say anything they want.

But, democracy doesn’t work like that in science. Science is the field where democracy means "rule by the scientists , of the scientific methodology and for everyone's welfare"! (Yes, these are my words).

But The problem with “I’m entitled to my opinion” is that, all too often, it’s used to shelter disastrous beliefs that should have been abandoned long back. It becomes shorthand for “I can say or think whatever I like” – and by extension, continuing to argue is somehow disrespectful. And this attitude feeds, I suggest, into the false equivalence between experts and non-experts that is an increasingly pernicious feature of our public discourse. Perhaps that’s one reason why enthusiastic amateurs think they’re entitled to disagree with climate scientists and immunologists and have their views “respected.” And do you respect ignorance, misconceptions and superstitions in the same way as facts based on evidence and true knowledge? How silly that looks!

In democracies it is increasingly becoming difficult to stop anybody saying that vaccines cause autism, no matter how many times that claim has been disproven by medical science. And anti-vaccinationists keep saying it over and over again to mislead people.

But if ‘entitled to an opinion’ means ‘entitled to have your views treated as serious candidates for the truth’ then it’s a serious condition in science. Democracy doesn't work like that in this domain. You are entitled to have your opinions only if they don't harm the society you are living in. If you try to tell and mislead people that vaccination is a Government's conspiracy to sterilize you like Taliban does in Pakistan or spread rumours like vaccination causes autism like people of religion do in some countries, that right should have a re-look. Because we are unable to eliminate Polio from Pakistan, Afghanistan and Nigeria ( it is eliminated from rest of the world) because of religious fundamentalism that opposes science.

In the US, courts intervened to vaccinate some children when their parents refused to get them vaccinated because of their religious beliefs some time back. When the world is suffering by this backwardness, what should we do?

Keep quiet? Definitely not.

Educate them? We tried our best despite our inadequacies.

Try to open closed minds? We are doing our best.

But what do you do when people absolutely refuse to listen to you? When they are endangering the lives of others too with their adamant attitude?

How do you deal with a person who doesn't even know what a scientific evidence is? What a peer-reviewed paper is? And treat it as an 'opinion' of a person?

How do you deal with a person who cannot distinguish between an expert and a lay man on the street?

How do you deal with a person who refuses to even consider your evidence? How do you deal with a completely closed mind? How do you deal with a person who is blinded by baseless beliefs?

How do you deal with a person who is highly emotional and hits you, trolls you and uses abusive words while dealing with you?

How do you deal with a person who refuses to see reason no matter how much you tried?

How do you deal with a person who uses unscientific methods to convince you that s/he is right?

How do you deal with a person whose mind is still lodged in ancient times?

How do you deal with a person who tries to undermine, undo and make your efforts, mission and good intentions ineffective?

How do you deal with wrong circuits formed in a human brain?

If communicators fail to convince,
In order to solve the problems we face
There is no other go but to use force
The field that is getting maligned in this process is Science!

That is why they say science works better in communist countries! Not in democracies.

Like Plato said ... We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light!

Nobody can stop light, truth and facts from entering the public arena. When science fights back, nobody can win. We are on the right side.

Science wins in the end but it takes time. Have patience. 

Q: Can you name a dual purpose thing in science?

Krishna: This is the story told by Dr. APJ Abdul Kalam:

''Once I was working for Agni missile. I saw a professor come into my laboratory and he was seeing some materials which was light in weight and very hard. I was using this material for Agni missile. He asked me to come with him and took me to a hospital and showed me around 40 children. All of them were under 15 years. And none of them had two complete legs and they used calipers whose weight was around 4kg. They faced difficulty during walking; then professor suggested me to make calipers by the material which is used in Agni missile. After making calipers by that material, the weight of calipers was around 300g.''

Lightweight callipers was made up of glass filled polypropylene . These  lightweight callipers were lighter, sturdier, easier to make and cheaper. The cost of traditional leather and metal polio callipers at that time was between Rs. 3,500 and Rs. 4,000 but the new ones were just Rs. 500.

And there is a Kalam - Raju stent. The cost of the earlier stent was between Rs. 1 lakh and Rs. 1.75 lakh. Kalam managed to develop a new stent for just Rs. 10,000 using defense technology.

Q: Recently when I went to a medical shop and asked for a probiotic, they gave me a prebiotic plus a probiotic. What is a prebiotic?

Krishna: Prebiotics are non-digestible carbohydrates which become a food source for probiotics and induce the growth of bacteria and fungi which contribute to the well-being of the host. Prebiotics exist throughout the body, particularly in the gastrointestinal tract, where they alter the distribution of organisms within the gut.  Prebiotics increase the number and activity of two specific types of bacteria, bifidobacteria and lactic acid bacteria.

Food sources that contain prebiotics, including unrefined wheat, unrefined barley, whole wheat flour, raw oaks, raw honey, raw bananas, raw asparagus and raw garlic. Both raw or cooked onion contain prebiotics. The riches natural resources with prebiotics include acacia gums and inulin sources, such as jicama, chicory root and Jerusalem artichokes. Prebiotics are added to many different types of foods and are also available as dietary supplements.

When prebiotics combine with probiotics, they form a synbiotic, which includes live bacteria and sufficient fuel to thrive. Yogurt and other fermented dairy products are synbiotics. 

Probiotics supplements actually replace or add to natural bacteria already in a person's digestive system. People take probiotics to improve stomach and intestine health and to prevent conditions such as diarrhea, cramping and gas. These conditions are often caused by antibiotics. Studies are ongoing  about possible probiotic benefits in treating irritable bowel syndrome and colon cancers.

 The main probiotic  genera: Lactobacillus, Bifidobacterium, Saccharomyces, Enterococcus, Streptococcus, Pediococcus, Leuconostoc, Bacillus, Escherichia coli. 

Lactobacillus species include Lactobacillus plantarum, L. johnsonii, L. acidophilus, L. sakei, L. bulgaricus, L. salivarius .

Bifidobacterium species: Bifidobacterium infantis, B. adolescentis, B. animalis subsp animalis, B. animalis subsp lactis, B. bifidum, B. longum, B. breve

Saccharomyces bayanus (used for making wine) and Saccharomyces boulardii

Lactococcus lactis 

Enterococcus durans  and Streptococcus thermophilus also used for the production of yogurt alongside Lactobacillus delbrueckii subsp. bulgaricus)

Enterococcus faecium 

Bacillus species:B. subtilis, B. coagulans, B. subtilis, B. cereus.

Escherichia coli Nissle 

As the work is still in the research stage don't take these things without your doctor prescribing them.

Q: Who is the most brilliant scientist in the world?

Krishna:  You cannot pin point one like that. All knowledge is interdependent and important. Each person who contributes to this knowledge bank is important in his/her own way. Anybody who says one is important/ brilliant than the other really doesn’t know how the field of science works.

Some people take earning lots of money as brilliance.

Some think ‘being popular’ is brilliance.

Some take helping the world more as brilliance. Some take selflessness as brilliance. Some think solving a difficult problem is brilliance (don’t all scientists do these things except for the first two? The first two don’t count much any way for scientists).

All scientists are brilliant. That is why they have chosen to do difficult things.

Q: What is an indicator organism?

Krishna: Indicator organisms are microorganisms whose presence in any media indicates probable presence of pathogens.

Monitoring for specific bacterial pathogens is usually complex, expensive and time consuming. The AWQC tests for a select group of organisms known as indicator organisms, which are used to verify water quality.

Indicator organisms can be divided into two groups, those which are used as indicators of faecal contamination and those used as indicators of the efficacy of treatment.

Q: If an organ donor has cancer, will the recipient get it? 

Krishna: There have been some instances  in which organ transplants from people with cancer have been able to cause cancer in the person who got the organ. But there’s a major factor that makes this possible – people who get organ transplants take medicines that weaken their immune systems. This must be done so their immune system won’t attack and destroy the transplanted organ. This seems to be the main reason that cancer in a transplanted organ can, in rare cases, give cancer to the person who gets the organ. Organ donors are screened to reduce this risk.

Recent studies have shown that cancer is more common in people who get solid-organ transplants than in people who don’t – even when the donor doesn’t have cancer. This also appears to be due to the drugs that are given to reduce the risk of transplant rejection. Research has shown that the longer and more intensely the immune system is suppressed after transplant, the higher the risk of cancer. The drugs that allow the body to accept the organ also make the immune system less able to recognize and attack pre-cancer cells and the viruses that can cause cancer.

Q: If a pregnant woman has cancer, will it effect the foetus?

Krishna: If a woman has cancer during pregnancy, the cancer rarely affects the fetus directly. Some cancers can spread from the mother to the placenta (the organ that connects the mother to the foetus), but most cancers cannot affect the foetus itself. In a few very rare cases, melanoma (a form of skin cancer) has been found to spread to the placenta and the foetus.

Some cancer treatments are safe for the foetus during pregnancy or only during certain times of pregnancy. Others are not safe for the foetus at any time. Recent improvements in treatments and careful monitoring provide safer conditions for pregnant women with cancer so that it is more likely that the baby will be successfully delivered with good outcomes. It is important to know that a pregnant woman with cancer can give birth to a healthy baby.
Pregnancy can uncover cancer earlier than it would otherwise have been found. For example, a Pap test done as part of routine care during pregnancy can find cervical cancer. An ultrasound done during pregnancy may find ovarian cancer at an early stage.

 Q: At what age should we start vaccinating an infant?

Krishna: As the mother confers a measure of immunity to the child by transferring antibodies actively from from the maternal blood stream to the child during the last trimester the child will have a measure of protection during the first six months of its life. After this point the amount of maternal antibodies will be decreased to give any effective defense against pathogens. This means that most vaccines are designed to give the child their own immunity to the disease before the maternal supply of antibodies runs out. This is why we begin most vaccines at about two or three months of age.

However, some vaccines like hepatitis B V are given within 24 hours of birth.

Q: If we can't test Stephen Hawking's theories, is he really a scientist?

Krishna: Being a scientist is a state of mind. Yes, Hawking is a scientist in that sense. His mind works like that of a scientist’s.  

Q: Why do we have two nostrils rather than one big one?

Krishna: Oh, for double nose piercing! Jokes apart, we also have two eyes, two ears and two nostrils but only one trachea connecting them to two lungs.

We need our doubles for 1. stereoscopic vision - because the few inches of space between the eyes allow us to sense depth and perceive the world in three dimensions; 2. stereo sound, we have two ears because the difference in time between a sound reaching one ear over the other allows us to localize the source of the noise; and 3. super smelling - our nostrils are separated by a septum, in effect giving us two noses. Most of the time, one nostril allows less air to pass through than the other, with the nasal flow switching every few hours. This is called 'nasal cycle'. The slower airflow is caused by the tissue inside swelling with increased blood flow. While we don't consciously notice it, we breathe predominantly through one nostril at a time, and the other side becomes a bit congested and rests. You can test this yourself: try breathing through one nostril and then the other, and you'll probably find that one becomes stuffier than the other. This automatically changes over about four to six hours, so then the other side relaxes.

We smell using sensory cells high up in the nose, and some odour chemicals need more time than others to bind to these receptors. So a low-airflow nostril gives slow-acting odours more time to be detected, giving us a greater range of smell. So two nostrils provide a better ability to detect scents than one.

Also according to some experts, human development is responsible for this. This happens because early on, when the human body develops, it forms almost from a flat plate that folds itself in two.