keith scott-mumby

Hypersensitivity (a heightened state of extreme sensitivity) is another word you will hear applied to allergy. There are four distinct types of hypersensitivity: Types I to IV. These divisions are useful for discussion but may not necessarily occur as single entities in an individual. There is good evidence that Types I and III hypersensitivity can cause food-allergic symptoms, and some evidence that Type III mechanisms can be associated with gut disorders such as colitis. However, it is vital for doctors to appreciate that reactions to food and environmental substances may occur, proven empirically, without any of these mechanisms appearing to be invoked.

Hypersensitivity (a heightened state of extreme sensitivity) is another word you will hear applied to allergy. There are four distinct types of hypersensitivity: Types I to IV. These divisions are useful for discussion but may not necessarily occur as single entities in an individual. There is good evidence that Types I and III hypersensitivity can cause food-allergic symptoms, and some evidence that Type III mechanisms can be associated with gut disorders such as colitis. However, it is vital for doctors to appreciate that reactions to food and environmental substances may occur, proven empirically, without any of these mechanisms appearing to be invoked.

When an infective organism invades the tissues, a precise series of events are set up to limit spread of the foreigner and ultimately to destroy it. First a macrophage will encounter the intruder. It engulfs it and then ‘displays’ its characteristic proteins on the surface of the cell as a kind of “flag” or gotcha trophy. We call this chemical flag the antigen, since it generates the rest of the reaction. By means of chemical language (a sort of local hormone called a lymphokine), the macrophage attracts nearby T-helper lymphocytes. They ‘read’ the antigenic matter and go off to program B-cells to produce antibodies to this pattern. The antibody is our own, the good guys’ response, to lock onto antigen carriers and cripple them.

When an infective organism invades the tissues, a precise series of events are set up to limit spread of the foreigner and ultimately to destroy it. First a macrophage will encounter the intruder. It engulfs it and then ‘displays’ its characteristic proteins on the surface of the cell as a kind of “flag” or gotcha trophy. We call this chemical flag the antigen, since it generates the rest of the reaction. By means of chemical language (a sort of local hormone called a lymphokine), the macrophage attracts nearby T-helper lymphocytes. They ‘read’ the antigenic matter and go off to program B-cells to produce antibodies to this pattern. The antibody is our own, the good guys’ response, to lock onto antigen carriers and cripple them.

eyeNetra eyeNetra’s invention is a way to measure refractive errors (near or far-sightedness) by combining a simple optical attachment with software on a mobile phone. With billions of people in the developed and developing worlds alike needing glasses to stand any chance of being able to read, you can imagine the impact on illiteracy, unemployment and poverty. eyeNetra points out that the cost of providing eye glasses is down to $3, but the cost of an eye exam is still far too expensive.

eyeNetra eyeNetra’s invention is a way to measure refractive errors (near or far-sightedness) by combining a simple optical attachment with software on a mobile phone. With billions of people in the developed and developing worlds alike needing glasses to stand any chance of being able to read, you can imagine the impact on illiteracy, unemployment and poverty. eyeNetra points out that the cost of providing eye glasses is down to $3, but the cost of an eye exam is still far too expensive.

Let’s see how much you know. Pretend I came to you with this symptom and asked you what to do! Here’s the story: the patient is me (truly, this happened to me yesterday afternoon). I was sitting in a restaurant on the shores of lovely Lake Lucerne (photo), eating a plate with Parma ham and melon salad–a mix of watermelon, canteloupe and honeydew, drizzled with a balsamic dressing. It was delicious. Suddenly, there came a sharp pain in the side of my cheek. Gosh, I thought, a fish bone spike! Then I realized that was silly; but it could have been a spicule of bone from the ham. I felt it with my tongue and it seemed soft and small.

Let’s see how much you know. Pretend I came to you with this symptom and asked you what to do! Here’s the story: the patient is me (truly, this happened to me yesterday afternoon). I was sitting in a restaurant on the shores of lovely Lake Lucerne (photo), eating a plate with Parma ham and melon salad–a mix of watermelon, canteloupe and honeydew, drizzled with a balsamic dressing. It was delicious. Suddenly, there came a sharp pain in the side of my cheek. Gosh, I thought, a fish bone spike! Then I realized that was silly; but it could have been a spicule of bone from the ham. I felt it with my tongue and it seemed soft and small.

Learning something about the functioning of the immune system is essential to understanding the classic view of allergy. For those of you who want to know a little about this fascinating defense mechanism, take a deep breath and here goes!

Learning something about the functioning of the immune system is essential to understanding the classic view of allergy. For those of you who want to know a little about this fascinating defense mechanism, take a deep breath and here goes!

It is implicit in the body load model that you will be able to tolerate a definite level of each stressor and only by exceeding that do you move into overload. These limits may shift under different circumstances but there is always a line, drawn somewhere, which you must not cross if you want to remain well Bad allergens, then, are the ones of which even a tiny quantity puts you over the limit. Mild allergies are those which need a big dose of an allergen to come into effect. Probably mild allergies would not arise at all if the allergens were encountered in normal quantities, but several together can add up to trouble. It is even possible to imagine a scale and assign arbitrary numerical values. If your threshold limit is, say 10 points, a 12 allergy would put you straight into symptoms. But one or two 3s taken together would still have no effect; two 4s and a 3 might, so on. This can be represented diagrammatically.

It is implicit in the body load model that you will be able to tolerate a definite level of each stressor and only by exceeding that do you move into overload. These limits may shift under different circumstances but there is always a line, drawn somewhere, which you must not cross if you want to remain well Bad allergens, then, are the ones of which even a tiny quantity puts you over the limit. Mild allergies are those which need a big dose of an allergen to come into effect. Probably mild allergies would not arise at all if the allergens were encountered in normal quantities, but several together can add up to trouble. It is even possible to imagine a scale and assign arbitrary numerical values. If your threshold limit is, say 10 points, a 12 allergy would put you straight into symptoms. But one or two 3s taken together would still have no effect; two 4s and a 3 might, so on. This can be represented diagrammatically.