Medical Microbiology

What does it mean?

Microbiology refers to the study of organisms that are too tiny to be seen by the naked eye. Medical microbiology thus refers to the study of these organisms in relation to humans. Perhaps those who do not have science background may find it difficult to appreciate this concept.

Once upon a time, before the microscope was invented, mankind was not able to see or to understand the existence of these organisms. With the invention of the microscope, the eye was able to sight the innumerable microorganisms and thus man was able to study them.

A microbiologist (a graduate with a degree in microbiology) is one who specializes in microbiological science. A medical doctor usually consults the microbiologist in making treatment-related decisions when there is a suspected infection.

Therefore, a clinical microbiologist has two roles:

1. Identify the microorganism responsible for the patient's infection.
2. Recommend the appropriate anti-microbial agents to alleviate the infection.

Why is it important?

Infection is a common disease due to the invasion by microorganisms. In order to treat infections effectively, the knowledge of medical microbiology is important.

Do you know the difference between a bacteria and a virus? Both are very small but the virus is even smaller. You can see a bacteria with a microscope but you may need a electron-microscope (expensive equipment) to see a virus.

Antibiotics are meant to kill bacteria and not virus. So, if you happen to have a mild cold without fever or sore-throat; the cause is normally due to some virus. So, will taking antibiotics help? Of course not. We need antibiotics to kill bacteria and we need anti-viral to kill virus. Point taken?

Recommended link:

http://en.wikipedia.org/wiki/Microbiology

Human Biochemistry

What does it mean?

Human biochemistry is the study of chemistry in the living human body.
Molecular biology refers to the study of molecular structures particularly the correlation of genes and the functional characteristics these produce.

The story of molecular biology:
Since the beginning of the 'Human Genome Project' (genome means the complete set of genetic material in a living thing i.e. human, in our context) to map out the entire sequence of the DNA (De-oxyribo-Nucleic-Acid) of mankind, this subject has been receiving a lot of publicity. Therefore, allow me to share with u some basic knowledge of this subject.

Our body is like a map of sorts. Each cell carries with it a 'master blueprint' containing the unique characteristics of every individual being. You could equate that with the 'operating system' or 'master software' of a computer. The 'blueprint' is encoded in a molecule called 'DNA'.

Sounds confusing? Don't worry. DNA is the chemical at the centre of the cells in living things. The chemical controls the structure and purpose of each cell and carries genetic information during reproduction.

The message carried by the DNA will determine the functions of each cell. Indeed, the capacity of one single DNA alone is enormous - it causes an overwhelming storage of information determining our individual perceptions and characteristics!

But wait! How does the DNA affect the person called "you"?
Aha! Each specific portion of the DNA carries with it a specific message or instruction. This can be quantified as a unit called 'gene'.
Mutation occurs when DNA sequences are altered by radiation or other mutagenic agents, causing abnormalities in the genes. These are linked to human diseases.

So, what does molecular biology have to do with you? Plenty! It can tell a thousand things about your genes. Since science invented the knowhow and technology in molecular biology science, the world has taken a dramatic leap forward. Consequently, there has been tremendous impact to the medical community and mankind.

Today, DNA testing can be made from surprisingly tiny samples of semen, hair, skin or blood - making it a boon for identification and research purposes. With it, the application possibilities of molecular biology are as unlimited as the variety of DNAs.

To know more about the human genome project, surf online and visit: http://www.ornl.gov/TechResources/Human_Genome/home.html

Why is it important to know medical biochemistry?

Chemical changes within the body can be normal or abnormal. However, there may be certain abnormalities requiring urgent attention and treatment. This could be an instance of high plasma potassium (hyper-kalaemia) level.
Monitoring biochemical changes is also one of the main reasons why a doctor would need to test your blood, especially when you are admitted to a hospital. Though the taking of blood may involve slight needle-prick pain, but it can do you a world of good and help the doctor in understanding your condition, faster and better.

The other area of importance in understanding human biochemistry is in drug treatment and drug research. Many discoveries have been made studying the natural bio-chemicals that exist within the body. Some drugs are based on molecular modifications of natural bio-chemicals. Further, new chemical entities or new molecules with potential benefits, when found, will be further tested and developed to determine the therapeutic effects.

Links:

(Basic to mid-level: suitable for public and medical students):
Biochemistry made easy:
http://www.angelfire.com/biz3/easybiochemistry/biochemistry.html

http://en.wikipedia.org/wiki/Biochemistry

Great! You're doing well.

What is Human Pathology?

What does it mean?

Pathology is the study and analysis of 'diseases'. In layman's terms, these are ailments or health problems. Medically, disease refers to the alteration of 'structure' (anatomy) or/and function (physiology) of the human body. It is like a combination of changes in the human body caused by specific factors. This could simply mean an abnormal change e.g. growth or an abnormal function e.g. high blood pressure. The correlation of these is considered pathological and pathology is the study of these changes.

There's more to pathology than this. Check out the following!

• Histo-pathology refers to changes seen under the microscope.
• Cytology refers to the study of individual cells in order to determine the abnormality.
  

A disease is not just any disease. Look around you, read the papers. You may observe that there can be so many causes that bring about a certain condition or ailment:

• Physical Trauma e.g.: motor vehicle accidents, radiation.
• Chemical agents e.g.: poisons, toxic chemicals.
• Microbial agents (so tiny you can't see them) eg: pathogenic bacteria, virus and fungus.
• Nutritional deficiency e.g.: lack of vitamins.
• Deprivation of oxygen e.g.: arterial obstruction leading to stroke or heart attack.

and

Abnormal reactions of the body due to unknown or undetected causes:

• Leading to abnormal inflammation e.g.: rheumatoid arthritis.
• Leading to abnormal growth e.g.: cancer.

and

• Genetic error: e.g. Down's syndrome.

Too much to swallow? The above are just categories to make you understand the complexity of diseases and how the mind set of the healthcare professionals in making a diagnosis of your problem, if you are sick.

Why is the study of pathology important?

Knowledge of pathology can help doctors to accurately diagnose various problems and determine the best possible solutions for the particular problem. Usually, a pathologist will provide the doctor the most possible or exact cause of a medical condition.

So what exactly does a pathologist do? Here are some examples.

The pathologist is also the specialist who will decide whether a particular breast lump is cancerous or not. The surgeon will take out the lump and send to the pathologist for histo-pathological examination. The pathologist will then prepare a report for the surgeon after inspecting the sample.

A forensic pathologist is a pathologist specializing in medico-legal investigations, conducting various scientific tests on objects or substances left at the scene of the crime. He or she must have a sound knowledge in pathology in order to help the police force to confirm the circumstances surrounding the cases.

Links:

(Basic to mid-level: suitable for public and medical students)
http://en.wikipedia.org/wiki/Pathology

(Advanced level: optional)
The next site is also a haven for doctors-to-be! (Be warned! These contain in-depth information on the subject matter and may seem dreary with a jargon of terms!):
http://www-medlib.med.utah.edu/WebPath/webpath.html#MENU

Your brains racking and having fun? Ready to soak up more stuff? Great! Please wait for our next article.

What is Human Physiology?

What on earth does that mean?

"Physiology' is the study of the 'functions' of the human body. For easier comprehension, the body is usually categorized using the 'systems' approach again (as in article 1):

1. cardiovascular system
2. gastrointestinal system
3. nervous system
4. respiratory system
5. endocrine system
6. urino-genital system
7. musculo-skeletal system
8. hematological system

You have an overview of what and where these systems are in article 1, now you will need to know the functions (why, when and how) of each of these systems.

This will be quite useful in understanding the breadth and depth of medicine. For something, which is as complicated as the human body, it is easier to divide the body (figuratively) into various parts or systems in order to understand it better.

That's like having a big cake and cutting it into pieces before we can eat it. For example an automobile has a suspension system, engine system, air-conditioning system, car-stereo system, cooling system etc.

Similarly with the human body, we have various systems each with their own functions and inter-connectivity as well. It's actually quite interesting to discover the functions of each system and how they work.

Why is it important?

Imagine someone is unwell. Before the doctor diagnoses the patient's ailment, he needs to know how the body functions normally before he can gauge what is abnormal. You need to understand the physiology of the cardiovascular system, to understand how high blood pressure affects the various parts of the body. You need to know what a normal blood pressure is before one can say whether a blood pressure is high or low. Stress? Don’t worry. No exam. Just take your own sweet time to surf on the recommended link that we have recommended below. In no time, you will speak like a healthcare professional.

Physiology is also an important basic subject for pharmacology (coming soon). An in-depth understanding of how the body functions is necessary to develop a drug that will act at the particular organ and subsequently will influence the function of the human body.
A medical practitioner needs to know the functions of the various systems and the possible problems if a particular system breaks down. This will help the doctor to narrow down to a particular system and then further narrow down to a specific part of the system (therefore, the importance of knowing anatomy).

Vice versa, a doctor has to know what problems relate to what system. Say a patient comes with a problem, a doctor will have to know which system to focus on.

Recommended link for you to navigate:
(Basic to mid-level: suitable for public and medical students)
Click on to this link (also designed for medical student) and zoom right into the autonomic nervous system. Find out how drugs can influence this system and the consequences:
http://physioweb.med.uvm.edu/301/

Also:

http://en.wikipedia.org/wiki/Human_physiology

What is Human Anatomy?

"Human Anatomy" refers to the study of the human structure. Knowing the physical structure of the human body inside out is essential, especially for a surgeon.

In order to know 'where' to cut and 'what' not to cut, the poor surgeon has to know not only the external structure but also the internal structure and most importantly the relationship of one part to another. That's not easy, if you know what I mean. One needs to know as well, the meaning of specific terms. Such understanding is essential before we move on to other topics later.

Let us begin with the most basic structure of the body, the 'cells'. Since the microscope was first invented, cell studies were made possible. Simple life forms e.g. the amoeba, is a one-cell life form.

With the invention of more powerful tools, we can now studying human cells at the molecular level. Every human cell contains DNA, which is like the 'master software' of a computer system. Not only are we looking at the structure of the DNA (the 'blueprint' of a human) but we are mapping out the sequence of the DNA as well.

Easy?

From the micro (small) level, we now move on to the macro (big) level. A group of cells is referred to as 'tissue', and a group of different tissue is referred to as an 'organ'; and a group of organs with a specific function is referred to as a 'system'. Remember:

1. THE MOST BASIC PART OF THE BODY = CELL
2. GROUP OF CELLS = TISSUE
3. GROUP OF TISSUE = ORGAN
4. GROUP OF ORGANS = SYSTEM

For example, the 'cardiovascular system' is a combination of the heart (a collection of cardiac muscles, connective tissues and nerves) and all the blood vessels in the human body with a specific function 'to deliver oxygen and nutrients to the cells and also clear bodily wastes'.
The foundation of the human body is the skeletal system. Overlying the skeletal system are soft tissues and organ systems. There are various other systems in our body. It will be useful to know what the systems are, as medical knowledge is specific according to the systems approach. If you know that, you will appreciate the various medical specialists and the areas they specialize in. The system classifications are useful for understanding the complexity of the human body in an orderly manner.

Why is it important for me to know?

So that you could communicate correctly with your doctor and it will also help you to narrow down the possible causes of your problem. If you suffering from pain, the first question a doctor would normally ask is where it is? Location of the pain e.g. upper part of the body and the lower part of the body means different internal organs are affected.

For a good overview of the human anatomy in graphical format, try visiting the following websites: (hyperlinks provided)

EASY GOING FOR BEGINNERS! (Basic level: suitable for public)
http://www.innerbody.com/htm/body.html

http://en.wikipedia.org/wiki/Human_anatomy

If your thirst for more information is overwhelming, you may also want to surf on sites with more technicalities) (Advanced level: optional)

The electronic version of Gray's anatomy (not the Grey’s anatomy as in the famous movie TV series) textbook is here: http://www.bartleby.com/107/

More for you to digest!
The visible human project:
http://www.nlm.nih.gov/research/visible/visible_human.html

Enjoying yourself? Go on, move ahead and proceed to the next article (what is human physiology?).