Immune Response, Toxins, & Nutrition

Immune Response to Microorganisms Immune system – the body system that protects against pathogens and cancer Immunity – the ability to resist disease The immune system has 3 lines of defense:

Immune Response 1st line of defense (nonspecific): skin, ciliated cells, mucus membranes – act as barriers and traps

Immune Response 2nd line of defense (nonspecific): increased body temperature (fever) to create conditions unsuitable for pathogen growth; increased blood flow to injured or infected site resulting in inflammation; blood brings white blood cells called macrophages that engulf and kill pathogens

Immune Response 3rd line of defense (specific): macrophages activate helper T cells that (1) activate other T cells that destroy infected cells and (2) activate B-cells to make antibodies; antibodies attach to pathogens, clumps them, and signals them for destruction.

Passive vs. Active Immunity Active Immunity – body’s own immune response is activated and produces antibodies; occurs when a pathogen or a vaccination is introduced into the body; long-term effect; once you get exposed to pathogen, you retain those antibodies for awhile, explaining why some diseases are only contracted once in a lifetime

Active Immunity Memory B cells keep antibodies “on file” in case of future exposure to antigen

Passive vs. Active Immunity Passive Immunity – antibodies are introduced into the body (not a result of immune system response); example – mother transfers her immunity to infant during breast-feeding; effects are short-term

Vaccines Made from weakened pathogens, pathogen parts, dead pathogens Injections, nasal sprays, ingested Causes body to make antibodies that can be used if it is exposed to the “real deal”; will shorten or prevent illness There are risk factors – allergic reactions, actually getting disease from vaccine, etc.

Vaccines now available for:

Toxins

Effects of Environmental Toxins Toxin – poisonous substance that can cause disease Symptoms depend on dose, how long you’ve been exposed, the way it got in the body, and body response.

Effects of Environmental Toxins Mercury Sensory impairment (vision, hearing, speech), lack of coordination, disturbance in sensations (pins and needles), muscle weakness, skin rash, mood swings, memory loss, mental disturbance Damage to central nervous system, liver, digestive tract, kidneys, prolonged exposure leads to brain damage and death Major sources – ingestion of contaminated food (mainly fish) and water, air pollution, improper use of items such as thermometers and fluorescent light bulbs

Mercury From 1932 to 1968, the Chisso Corp. dumped nearly 27 tons of mercury waste into Minamata bay, Japan. In the mid-1950’s, a strange disease emerged that seemed to affect cats, birds, and people. http://science.education.nih.gov/supplements/nih2/chemicals/activities/lesson5.htm or http://aileenarchive.or.jp/minamata_en/slides/swf.html

Effects of Environmental Toxins 2. Lead Major sources – lead paint (1978), toys, lead bullets, sinkers, plumbing, air (when we used leaded gas), pewter Symptoms: Child: irritability, weight loss, sluggishness, abdominal pain Adult: pain/tingling in the extremities, muscle weakness, headache, abdominal pain, memory loss, mood disorders, reduced sperm count, abnormal sperm

Lead Lead Paint chips

Nutrition

Nutrition Good Nutrition – can maintain good health and prevent disease Nutrients are substances the body needs to obtain energy and build and replace tissue Carbohydrates – energy Fats – store energy, insulation, building cell membranes Proteins – chemical reactions, body structure, traits Vitamins – naturally occurs in plant and animals; help body with specific functions Minerals – not made by living things (ex. Calcium, iron) Good nutrition is a balance of all of the above

Nutrition 2. Bad Nutrition – can lead to: Obesity – the wrong amounts of sugars/carbohydrates and fats coupled with lack of or too little exercise; also has genetic component; can lead to other complications such as diabetes

Nutrition Malnutrition – an overall deficiency of most or all the nutrients; can lead to other complications including decreased immunity Malnourished child with dysentery

Nutrition Specific deficiencies – not enough of certain vitamins and minerals can lead to specific health problems Examples: Scurvy – deficiency of Vitamin C; causes inflammation of the tongue, spongy gums, blue and black spots on skin, sunken eyes, pallor, corkscrew hair, nosebleeds; was common among sailors

Nutrition Goiters – deficiency of iodine; causes swelling of the thyroid gland (in your neck), tight feeling in your throat, coughing, trouble swallowing and breathing; not a problem in U.S. since iodized salt.

Nutrition Osteoporosis – disease caused by lack of enough calcium in the diet over many years; causes brittle bones, and hunched/stooped over appearance. For more about vitamin & mineral needs/deficiencies: http://www.changingshape.com/resources/references/vmchart.asp