ANTIPYRETICS

 Dear students...

This post discuss about antipyretics and anesthetics.

Antipyretics:

A drug that prevents or reduces fever by lowering the body temperature from a raised state. They work by influencing the body's hypothalamus(which keeps the body balanced in a stable state called homeostasis) the region responsible for regulating temperature. During an infection or illness, the body releases certain chemicals called pyrogens, which trigger the hypothalamus to increase the body's temperature as a defense mechanism. Antipyretic drugs intervene in this process, helping to bring down the elevated temperature and provide relief from associated symptoms like discomfort, chills, and body aches.

Some of the common antipyretics used in daily life are discussed here.

Aspirin:

Aspirin is a nonsteroidal anti-inflammatory drug (NSAID). It was the first of this class of drug to be discovered. Also known as acetylsalicylic acid (ASA) is a commonly used drug for the treatment of pain and fever due to various causes. Acetylsalicylic acid has both anti-inflammatory and antipyretic effects. This drug also inhibits platelet aggregation and is used in the prevention of blood clots stroke, and myocardial infarction

Therapeutic uses:

Fever

Head ache

Inflamation

  

Paracetamol:

It is a class of para-aminophenol derivatives. It has both antipyretic and analgesic effects. It occurs as white crystalline powder, odourless and soluble in alcohol and sodium hydroxide solution.  It is also soluble in boiling water and the solution is acidic in nature. It is used in the form of tablets, suspensions, syrups. The usual dose is 0.5 to 1.0 g for every four hours.

Therapeutic Uses:

Joint and muscle pain

Ibuprofen (Brufen):

Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID) derived from propionic acid. It was first launched against rheumatoid arthritis.  Ibuprofen is insoluble in water, but very soluble in most organic solvents like ethanol.

Synthesis:

It is synthesized by the acylation of iso-butylbenzol by acetyl chloride. The resulting iso-butylbenzophenone (3.2.21) is reacted with sodium cyanide, giving oxynitrile (3.2.22), which upon reaction with hydroiodic acid in the presence of phosphorus is converted into 2-(4-iso-butylphenyl)propionic acid (3.2.23), which subsequently undergoes phases of dehydration, reduction, and hydrolysis.

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ANTIBIOTICS -II

 Dear students,

Here we are going to see about the next two antibiotics.

Chloramphenicol

Chloramphenicol is an antibiotic and is in the class of antimicrobials that inhibits protein synthesis. Chloramphenicol is a synthetically manufactured broad-spectrum antibiotic. It was initially isolated from the bacteria Streptomyces venezuelae in 1948 and was the first bulk produced synthetic antibiotic. It can be used against Gram-positive, Gram-negative, and anaerobic bacteria. It works by inhibiting protein synthesis thereby preventing the formation of bacterial protein.  Chloramphenicol can be administered topically ear drops, or as an eye ointment. It can also be given intravenous injection or taken as oral capsules. 

Structure:

It is a dichloro-substituted acetamide containing a nitrobenzene ring, an amide bond and two alcohol functions.  In 1949 a team of scientists at Parke-Davis including Mildred Rebstock published their identification of the chemical structure and their synthesis.

         

Therapeutic Uses:

1. Typhoid

A life-threatening infection caused by the bacterium Salmonella Typhi. Without treatment, there is a small chance of death from typhoid fever complications.

2. Whoophing cough:

Whooping cough (pertussis) is a highly contagious respiratory tract infection. In many people, it's marked by a severe hacking cough followed by a high-pitched intake of breath that sounds like "whoop." Once you become infected with whooping cough, it takes about seven to 10 days for signs and symptoms to appear, though it can sometimes take longer.

 

3. Urinary Tract Infection:

 

A urinary tract infection (UTI) is an infection in any part of the urinary system. The urinary system includes the kidneys, ureters, bladder and urethra. Most infections involve the lower urinary tract — the bladder and the urethra. Women are at greater risk of developing a UTI than are men. Urinary tract infections are often treat with antibiotics.

II Streptomycin:

Streptomycin is the first discovered aminoglycoside antibiotic, originally isolated from the bacteria streptomyces griseus. It is now primarily used as part of the multi-drug treatment of pulmonary tuberculosis. It has additional activity against several aerobic gram-negative bacteria.  It interferes with ribosomal peptide/protein synthesis. It binds to bacterial ribosome, inhibiting its functionality and halting further protein synthesis through inhibition of peptide bond formation. 

Selman Waksman and eventually Albert Schatz were recognized with the Nobel Prize in Medicine for their discovery of streptomycin and its antibacterial activity. 

Structure: 

Streptomycin is a amino cyclitol glycoside that consists
 of streptidine having a disaccharyl moiety
 attached at the 4-position. 

Therapeutic Uses:

1. Tuberculosis

Tuberculosis (TB) is an infectious disease that most often affects the lungs and is caused by a type of bacteria. It spreads through the air when infected people cough, sneeze or spit. Certain conditions can increase a person’s risk for tuberculosis disease:

diabetes (high blood sugar), weakened immune system (for example, HIV or AIDS), tobacco use.

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DRUG (MEDICINE)

 Hi....

This post deals with some drugs and their therapeutic applications

What are drugs? 

Pharmacology defines drug as any substance (other than food) that is used to prevent, diagnose, treat, or relieve symptoms of a disease or abnormal condition. Drugs can also affect how the brain and the rest of the body work and cause changes in mood, awareness, thoughts, feelings, or behavior. Some types of drugs, such as opioids, may be abused or lead to addiction.

Today, medicines come from a variety of sources. Many were developed from substances found in nature, and even today many are extracted from plants. Some medicines are made in labs by mixing together a number of chemicals. Medicines can be delivered in many ways, such as:

• liquids that are swallowed
• drops that are put into ears or eyes
• creams, gels, or ointments that are rubbed onto the skin
• inhalers (like nasal sprays or asthma inhalers)
• tablets that are placed under the tongue (called sublingual medicines; the medicine is absorbed into blood vessels and enters the bloodstream)
• injections (shots) or intravenous (inserted into a vein) medicines

Most Important Drugs

Insulin, Ether, Polio vaccine, Aspirin, Antibiotics.

What are Antibiotics?

Antibiotics are medicines that are used to treat as well as prevent bacterial infections. They inhibit growth and sometimes destroy the microorganisms that cause infections. 

Antibiotics use is encouraged because it is fairly harmless to human beings and animals. There are two main ways in which antibiotics target bacteria. They either prevent the reproduction of bacteria, or they kill the bacteria, for example by stopping the mechanism responsible for building their cell walls.

Antibiotics

 

Some common examples of antibiotics are as follows:

PENICILLIN

STREPTOMYCIN

CHLORAMPHENICOL

First we are going to see about Penicillin. It is a group of antibiotics (medications used to treat bacterial infections) that work in a specific way to destroy bacteria in your body. Types of penicillin and drugs closely related to them are called “penicillins.” They’re a subclass of beta-lactam antibiotics. Penicillin antibiotics come in oral form (pills or liquid you swallow) and IV form (liquid that a provider injects directly into your vein).

How does penicillin work?

Penicillin works by attaching to the wall of bacteria cells. It damages the cell wall and eventually destroys the bacteria.

Sir Alexander Fleming 
a Scottish physician and microbiologist
discovered penicillin in 1928

 

What is penicillin used for?

Pneumonia is inflammation and fluid in your lungs caused by a bacterial, viral or fungal infection. It makes it difficult to breathe and can cause a fever and cough with yellow, green or bloody mucus. 

  

Meningitis is an inflammation of the protective layers
surrounding your brain and spinal cord (meninges).

Diphtheria - a serious bacterial infection that usually affects the mucous membranes of the nose and throat.

Diphtheria is a highly contagious, infectious disease caused by a bacterium called Corynebacterium diphtheriae. People with diphtheria have serious breathing and swallowing problems, and they may develop sores on their skin.

Tetanus - Tetanus is a serious disease of the nervous system caused by a toxin-producing bacterium. The disease causes muscle contractions, particularly of your jaw and neck muscles. Tetanus is commonly known as lockjaw. There's no cure for tetanus. Treatment focuses on managing symptoms and complications until the effects of the tetanus toxin resolve.

Rheumatic fever occurs after infections with a  bacteria called Streptococcus pyogenes or group A streptococcus. This bacteria  attacks healthy tissues in the body. These tissues become swollen or inflamed. It can cause severe illness in the heart, joints, skin, and brain. It’s a relatively serious illness that usually appears in children between the ages of 5 and 15.

Dear students, this post shares some idea about drugs and their applications. Though there are wide variety of antibiotics, only penicillin is discussed here. The other two antibiotics will be discussed in a different post.

Thank You.

How Polymers react to heat??? Thermal properties of polymers

 Hello....

We know that water has the three physical states of solid, liquid, and gas. And we are likely familiar with the state changes such as melting, freezing, boiling (vaporization), and condensation. The large molecules of polymers do not follow the classical physical states and phase transitions observed by small molecules. 

Below is an overview of how polymers change as heat is applied.

Soften: as heat is added, polymers change from a stiff solid at low temperatures to a soft pliable material at the glass transition temperature, Tg.

Melt: similar to the wax of a candle, crystalline polymers can melt when heated but usually at relatively high temperatures. Some polymers are amorphous and do not show a clear melt transition, Tm.

Decompose: polymers do not vaporize (become a gas) after melting, they breakdown or depolymerize into smaller molecules (fragments) at high temperatures.

Burn: for many commodity polymers the fragment vapors will burn in the presence of oxygen and heat (ignition source)

Soot: some polymers produce large amounts of soot when they burn

Here is the study material about glass transition temperature Download

METHODS OF POLYMERIZATION

Dear students...

In this post I have shared video link about various methods of polymerization. Hope this will be useful to you. You can also view the study materials form the link given at the end.

Polymerization reaction may take place in any of the three states of matter- solid, liquid, gas. The solid state reactions are usually slow, they are not considered practical for this reason. The gas-phase reactions do take place but normally they require maintenance of high temperatures, a condition in which almost all high molecular weight polymers become unstable. Hence almost all commercial process of polymerization are liquid phase reactions.

LIQUID-PHASE REACTIONS:

→ Homogenous type

 Bulk Polymerization

 Solution Polymerization

→Heterogeneous type

 Emulsion Polymerization

 Suspension Polymerization/Pearl/Bead Polymerization

The homogenous or heterogeneous terms refers only to initial conditions of the system and are not to the subsequent conditions 

Methods of polymerization: Video Part 1

Study material to downlod