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Messages - Farhana Israt Jahan

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Very informative post. But if you mention the source it will be more authentic.

Thanks for sharing the information.

Medicinal Chemistry / Accidental discovery of some drugs
« on: February 05, 2020, 01:45:29 PM »
Accidental discovery also known as 'Serendipity', has played a pivotal role in the discovery of many drugs used today. Many important discoveries in medicinal chemistry are due to serendipity. Some Examples are given below:

Penicillin: It is the first discovered antibiotics. By 1927, Fleming was investigating the properties of staphylococci. On 3 September 1928, Fleming returned to his laboratory having spent August on holiday with his family. Before leaving, he had stacked all his cultures of staphylococci on a bench in a corner of his laboratory. On returning, Fleming noticed that one culture was contaminated with a fungus, and that the colonies of staphylococci that had immediately surrounded it had been destroyed, whereas other colonies farther away were normal. Fleming showed the contaminated culture to his former assistant Merlin Price, who reminded him, "That's how you discovered lysozyme. Fleming grew the mould in a pure culture and found that it produced a substance that killed a number of disease-causing bacteria. He identified the mould as being from the Penicillium genus, and, after some months of calling it "mould juice", named the substance it released penicillin on 7 March 1929.

Vaccine of Chicken Pox: Serendipitous connection of dots led to the discovery that vaccination is a general method for preventing infectious diseases.  It occurred during Pasteur’s struggle to establish the germ theory of disease, specifically in the case of chicken cholera.  To demonstrate that chicken cholera was caused by germs and not some toxins in the blood, it was important to isolate germs from toxins, which was very difficult in those early days.  To purify germs, Pasteur extracted them from diseased chickens, grew them in cultures outside the body, and injected the culture into healthy chickens, which would become sick and a new source of germs, hopefully less contaminated with toxins.  An autumn day in 1879, he injected a culture into some chickens and found them to be hardly affected.  Later, because of a mix up or shortage of supply, the “used” chickens were recycled, together with some new chickens, in experiments to test a fresh virulent culture.  This time the new chickens all died but the lucky recycled chickens remained unscathed.  A colleague recalled that when Pasteur heard of this surprising development, he “remained silent for a minute, then exclaimed as if he had seen a vision: ‘Don’t you see that these animals have been vaccinated!

Sildenafil: Researchers at Pfizer had worked for years on sildenafil, an inhibitor of the PDE5 enzyme, which they hoped would be effective in relaxing coronary arteries and relieving chest pain.  Their hope was dashed by 1992.  Only one out of ten candidates entering clinical trials successfully passes through the gauntlet and reaches consumers, but statistics is little consolation for those who see their projects falling on the heap of nine.  Gloomily, the researchers terminated the trial and asked participants to return the unused drug.  Many men refused, clutching to the drug as if it was gold.  Idiosyncrasies being present in all clinical tests, researchers gave the objection little thought until they heard rumors about the drug’s side effects on sex life and, more important, read a paper on the role of PDE5 in the chemical pathway of erection.  Gloom evaporated in the excitement that sildenafil may be a blockbuster after all.  This time, their expectation was confirmed by new clinical tests on impotent men.  They stumbled on an effective drug for erectile dysfunction Pfizer would market as Viagra.

Medicinal Chemistry / ORPHAN DRUG and ORPHAN DISEASE
« on: February 05, 2020, 01:36:34 PM »
An orphan drug is a pharmaceutical agent that has been developed specially to treat a rare medical condition; the condition itself being referred to as an orphan disease. Orphan disease is a disease that affects a small percentage of the population.

Examples of orphan disease & drugs:
Wilson’s disease: Penicillamine was developed to treat wilson’s disease, a rare hereditary disease that can lead to a fatal accumulation of copper in the body. The drug was later found to be effective in treating arthritis.
Cystic fibrosis: Cystic fibrosis is an autosomal recessive genetic disorder affecting most critically the lungs & also the pancreas, liver & intestine. In the 1980s, cystic fibrosis patients are rarely found. Drugs like pulmozyme & tobramycin both developed that significantly improve their quality of life.

Medicinal Chemistry / What is Smart drug and Sentry drug?
« on: February 05, 2020, 01:34:57 PM »
Sentry drug is also called Arbor drug. It was founded by Eugene Applebaum and Bruno Manni in 1974.
A sentry drug is a drug which is administered alongside another drug to enhance the latter's activity. The role of sentry drug is to guard or assist the principal drug. Many sentry drugs protect their partner drug by inhibiting an enzyme which metabolizes the latter (e.g. carbidopa and levodopa).
Sentry drugs have also been used to localize the site of action of local anaesthetics and to increase the absorption of drugs from the GIT (e.g. adrenaline & procaine), adrenaline constricts the blood vessels in the surrounding area of the injection and so prevents procaine being rapidly removed from the area by the blood supply.

Smart drugs are drugs, supplements, nutraceuticals, functional foods or any chemical ingested that may improve mental function. Some of these drug improve overall IQ while others are more focused e.g. on memory boosting or attention span or creativity. These substances are also called neuro enhancers, cognitive enhancers, intelligence enhancers or "nootropics."
"Nootropic" comes from Greek - "noos" means mind and "tropos" means changed, toward, turn.

Smart drugs are thought to work by altering the availability of the brains supply of neurochemicals (neurotransmitter, enzymes & hormones) by increasing blood flow to the brain (flooding) thus improving brain’s oxygen supply or by stimulating nerve growth.

Examples of Smart Drugs
Traditional herbs: Vitamin B & D, omega-3, isoflavones
Prescription drugs: Methylphenidate and Dextroamphetamine: Stimulants used to treat attention deficit hyperactivity disorder.
Nutrients: Choline and derivatives: precursor to acetylcholine. eggs, meat and milk are good sources of choline.
Recreational agents: Tetrahydrocannabinol (THC), amphetamine, tobacco.

Allied Health Science / Re: Prevention from Dengue
« on: February 05, 2020, 01:22:39 PM »
Time needed post. Thanks for sharing

Cold / Flu / What is adenoiditis & its treatment?
« on: March 31, 2019, 01:32:39 PM »
What is adenoiditis?:
Everyone gets a sore throat from time to time, and sometimes the tonsils in your mouth can become infected. However, tonsils are not the only vulnerable glands in your mouth. Adenoids, located higher up in the mouth -- behind the nose and roof of the mouth -- can also get infected. Enlarged and inflamed adenoids -- called adenoiditis -- can make breathing difficult and lead to recurring respiratory infections.

What Are Adenoids?
Adenoids are a mass of tissue that, along with our tonsils, help keep us healthy by trapping harmful germs that pass through the nose or mouth. Adenoids also produce antibodies to help body fight infections.
Even though adenoids help filter out germs from our body, sometimes they can get overwhelmed by bacteria and become infected. When this happens they also get inflamed and swollen. This condition is called adenoiditis. It is most commonly seen in children, but sometimes affect adults.
Child's doctor may also recommend the tonsils be removed at the same time since adenoiditis and tonsillitis often go hand in hand. Surgery to remove the tonsils is called a tonsillectomy.

Source: WebMd

What Are the Symptoms of Adenoiditis?
Symptoms of adenoiditis can vary depending on what is causing the infection, but may include:

sore throat
stuffy nose
swollen glands in the neck
ear pain and other ear problems

How Is Adenoiditis Treated?
Adenoiditis is treated with antibiotics. However, if the child has frequent infections, including ear and sinus infections, or antibiotics do not help, or if child has ongoing breathing problems, surgery may be needed to remove the adenoids. This procedure is called an adenoidectomy.
Child's doctor may also recommend the tonsils be removed at the same time since adenoiditis and tonsillitis often go hand in hand. Surgery to remove the tonsils is called a tonsillectomy.


Faculty Sections / Re: Proper diet can help fight cancer
« on: March 31, 2019, 09:49:43 AM »
Nice post

Pharmacy / Re: Several foods... essential for anemia
« on: March 30, 2019, 12:34:34 PM »
Informative post

Good to know.

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