A Brief Overview of the Human Immune System

An Overview of The Human Immune SystemThe human immune system is made up of two major components – the nonspecific (innate) immune system and the adaptive (targeted/specific) immune system. These two components of the immune system work in co-operation to defend the body against invading and harmful organisms such as parasites, fungi, bacteria and viruses.The First Line of Defense in the Anti-Disease SystemThe primary component of a person’s immunity (first line of defense) is made up further of two parts – the first being the skin and mucous membranes (physical barrier). If the external skin barrier has been compromised, the second layer of defense is then activated in response. The major indicator of the activation of the secondary defense system is inflammation – which is characterized by a localized redness and swelling wherever the invading organisms are present. It is also systemically marked by a raise in body temperature (fever) and the presence of pus around the infected area and possibly the presence of white blood cells in the urine.A raised body temperature (fever) is one of the ways that the body maintains its homeostasis (balance) so that all of the chemical reactions that take place in the body occur in a place of optimum efficiency, and this is necessary for achieving ultimate wellness and health. A raised body temperature aids in destroying foreign organisms.Parts of the Primary Defense SystemThe different constituents of the primary defense system include the following:Phagocytes – these include macrophages and neutrophils. Their job is to chiefly ingest and in doing so, destroy invading harmful pathogens. The process whereby a phagocyte emerges from the bloodstream and into the tissues to ingest invading organisms is called phagocytosis. This is done by the phagocyte recognizing the harmful organism, and locking onto it, and thereby ingesting it. Some bacteria mask their identities, and can confuse phagocytes; the immune system can overcome this by covering pathogens with opsonins. These are complement proteins that then give “handles” for the phagocytes to lock onto invading pathogens and thereby destroy them. In the case where certain pathogens are resistant to these, the immune system then reacts by providing additional supports – helper T cells release chemicals that stimulate the macrophages, which then release additional destructive enzymes that are lethal to these pathogens. Neutrophils also pierce the invasive organism’s membrane by using defensins. When phagocytes are unable to ingest the invading organisms, they release their toxic weapons into the extracellular fluid, which then destroys these pathogens. Neutrophils destroy themselves in the process of eradicating pathogens, but macrophages can continue to destroy invasive substances.Natural Killer Cells – are present in the bloodstream and also the lymphatic system. These cells can lyse and subsequently destroy cancer cells and virus infected body cells before the adaptive immune system is switched on. They are part of a group of cells called large granular lymphocytes. They can eradicate a large number of foreign harmful cells and organisms, and they are non-specific in their destructive targeting. Natural killer cells destroy harmful cells by contacting them and causing programmed cell death (also known as apoptosis). They also give off strong chemicals which promote the body’s inflammatory response.Inflammation is part of the primary defensive immune system. It is activated by the external trauma to body tissues, or via intense heat (resulting in burns), chemical irritation to the skin, or infection by fungi, viruses and bacteria. The inflammatory response results in several resultant effects: prevention of spread of infection; disposal of dead cells and destroyed pathogens; alert of immune system and foundation for tissue and cellular repair. It begins with a chemical alarm – chemicals being released into the extracellular fluid – these are released from injured or stressed cells. These can also be triggered by the release of certain proteins in the blood (histamine response). Macrophage cells (and certain other tissues) have special detection abilities which can then activate the immune system. The other effect of inflammation includes the dilation of the blood vessels around the infection, allowing more blood flow to the area, which promotes rapid healing. The blood vessels and surrounding tissues also become more permeable, allowing for the migration of immune system cells more rapidly to the affected body part. Exudate is the resultant fluid from the increased movement of cells and blood to the affected area, and this causes localized swelling. This fluid can press against nerve endings, causing the pain response. Phagocyte mobilization occurs as a result of inflammation, and invading organisms are destroyed.The Secondary Response SystemThe Adaptive (or Secondary) Component of a person’s immunity is the body’s built in specific immune response, which is acquired throughout a person’s lifetime of exposure to various invading organisms. The adaptive immune system is activated after the immediate response of the primary immune system response, and acts for longer than the primary immune defense. The theory of immunization, by the initial exposure of a person to a dead or disabled pathogen, and its resultant effect being that the immune system develops antigens specific to that pathogen operates within the secondary defense system.The secondary adaptive immune system is a targeted immunity to various organisms, and its activation causes the body to react and destroy any specific pathogen it has been programmed to respond to. It prevents reinfection by the same organisms. Often the secondary immune system will have been activated without a person being aware, they may have very mild symptoms of malaise for 24 hours or less, and that is the secondary immune system destroying a recognized pathogen.Immunisation programs are vital in helping to prevent the spread of many diseases, because it provides a targeted community wide response to the prevention of some very harmful diseases. Once an immune system has been programmed, it will destroy any recognized pathogen that it has been previously exposed to. This secondary targeted immunity takes time to develop, and that is why immunization programs are extremely effective in the prevention of disease.

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Behind the Notes – How to Read and Understand Piano Sheet Music

Have you ever tried to write down a piece of music for the piano?Even if you are not a composer, this is a task from which you could learn a lot. Among other things, it will show you how there is always a variety of ways to do it, even if all you want to do is to write simple notes. If you want to include instructions of touch, articulation or pedalling, the complications grow even more numerous.Through the centuries composers seem to have become more and more ambitious about this sort of thing – you only need to compare a score by Scarlatti or Bach with one by Debussy or Rachmaninoff to realise that. Of course, there are many exceptions to this, and one must not stop looking for all the subtle hints in early scores – this is the mistaken approach that led 19th century editors to feel the need to “fill in the gaps” left by their predecessors.If you know where to look for them, a composer like Mozart certainly gives you all the hints you need to play his music like he envisaged it. If the score sometimes allows for different approaches, that is because he leaves that particular decision to you. In that sense, nothing has really changed over the years, except that it would seem that modern composers tend to leave less to the taste of the performer. But quite possibly that is also partly a misunderstanding. The composer of early music probably trusted his performers more because he (at that time, composers were sure to be male) knew that they would recognise the conventions of the particular time and place. Of course he hoped that his art would survive his own circumstances, but he wrote it down for people of his own culture, with roughly the same sort of references and education.The composer of the 20th or the 21st century doesn’t belong to such a well-defined tradition. He or she often feels as if they are writing something entirely new, and for the whole world at once. Now, if you’re speaking to somebody on the other side of the globe about something that you just have invented, there are a lot more things to be explained than if you’re speaking to an old friend about a movie that you’ve both seen five times.So, what do we learn from this?Well, that it’s always important to look for the details of the score; that it’s important that you use reliable, urtext editions; that it’s important that you try to learn as much as possible about historical notation and performance practices. If you really want to understand a composer – Beethoven, Liszt, Chopin, Scriabin or anybody else – you need to reflect why they wrote their music down the way they did.

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Unsecured Personal Loans for Bad Credit: Getting the Best Terms

The fact that banks are rejecting more loan applications than in previous years is down to the poor state of the economy. But that is not to say that those of us with poor credit ratings are unable to get any form of funds. When the required criteria are met, then even unsecured personal loans for bad credit management are within reach.It might not seem unfair that traditional lending institutions are turning applicants down, but their policies have been tightened up because of the credit crisis of the last 4 years. But securing loan approval with bad credit is possible because there are alternative loan sources, not least online lenders.But as with all loans, the specific loan terms are what make it affordable or not. This is where chief attention should be paid, and should be the basis of your decision on whether to accept an unsecured personal loan package. But what are the best terms to seek and the important steps to securing them?1. Know Your Credit StandingThe first step towards getting the best terms on your unsecured personal loan for bad credit is to know what entitlements to expect. This is based on the credit score already secured, and how that affects the terms of the loan. For example, a very low credit score will mean a high interest rate is going to be charged.A credit score adjusts according to loan repayment habits, with those that fail to keep to a schedule seeing their score lower and interest applied on loans reach a much higher rate. However, the score can be reviewed, with any faults spotted in the score leading to an improvement, and a greater chance of getting loan approval with bad credit.However, it is important to note that credit scores are not the hugely influential facts that ensure an unsecured personal loan is approved. These aspects include the amount of guaranteed income, and the available space in the debt-to-income ratio.2. Avoiding Payday LendersThere is no denying that payday loans are the most reliable financing option, with repayment guaranteed directly from a paycheck. It means that lenders are fully confident they will get their money back. When it comes to getting an unsecured personal loan for bad credit purposes, then it is an good choice – at least in that regard.There are too many problems however, to make it an excellent choice all round. For a start, a payday loan causes more trouble than it solves. This is because the interest rate is very high (30%), and with the whole loan repaid in one go, a huge chunk of a paycheck is gone. So, even if loan approval with bad credit is all but guaranteed, there may not be enough to meet regular monthly obligations too.Another problem is that the loan sum is pretty small, usually limited to $1,500, so the impact it can make on a debt is minimal. Getting an unsecured personal loan means a larger sum to clear more debts, and a better repayment schedule.3. Choose Online LendersThe best deals are available online, and getting an unsecured personal loan for bad credit management from online lenders is pretty standard. That is because those lenders specialize in loans to people with low credit scores. The only issue is finding the right lender.The best terms can be easily found by searching through a comparison website, where analyzing the rates of interest and lifetime of the loans can be checked out quickly and easily.But even if a lender offers guaranteed loan approval with bad credit it is essential they are checked out on the BBB website. An unsecured personal loan is much better than a payday loan, but not if the lender is unscrupulous.

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