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Post by adapted on May 30, 2005 6:51:55 GMT -5
Title: Nutrition and the Immune Response -- a Review Author: Dreizen, S.; 1979 Journal: Int J Vitam Nutr Res; V. 49; Issue: 2; Pages: 220-8 Abstract: This compacted overview of the nutrition-immune response connection underscores the role of nutrition as a deterrent to infection. Malnutrition enhances the propensity to and heightens the intensity of infections by weaknening the various host defense mechanisms. Thus: 1. Deficiencies of vitamin A, niacin, riboflavin, folic acid, vitamin B12, pyridoxine, ascorbic acid, iron and protein disrupt the tissue barriers to infection. 2. Protein-calorie, folate, iron, pyridoxine and zinc deprivations markedly depress the cell-mediated immune system. 3. Deficiencies of protein, pyridoxine, folic acid, pantothenic acid, thiamine, biotin, riboflavin, niacin-tryptophan, vitamin A and ascorbic acid inhibit humoral antibody formation in mammalian systems. 4. Vitamin A lack prevents the formation of lacrimal, salivary and sweat gland lysozymes. 5. Complement, properdin, interferon and transferrin concentrations are reduced in those nutritional deficiencies that interfere with protein synthesis. 6. Protein-calorie, iron and folate deficiencies impair phagocytosis by interfering with phagocyte microbial killing power or with phagocyte production. 7. Protein, ascorbic acid and zinc deficiencies retard wound healing that prevents spread of infectious lesions. Notes: Journal Article Review So, is everybody eating a well balanced diet, consisting of the recommended, proportionate, three meals-a-day, and getting all the appropriate balances of vitamins & minerals? Cuz if not, it shore couldn't hoit!
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Post by bugsalive2 on May 30, 2005 19:27:21 GMT -5
The Integumentary System - The Skin
Consists of the skin and its derivatives including glands, hair and nails. The skin is also referred to as a keratinized epithelial membrane.
Structure of Skin
I. The Epidermis – Consists of a keratinized stratified squamous epithelium.
Cell Types – The epidermis contains a number of different cell types:
A. Keratinocytes – Most abundant cell type. Produce keratin, a tough, fibrous protein. Cells are held together by desmosomes. Organized into layers.
Stratum germinativum – Cells found just above the basement membrane which undergo rapid cell divisions. Also called the stratum basale. Basal cell carcinoma originates here.
Stratum spinosum is a middle portion of the epidermis several cells thick. The name derives from the appearance of these cells after they are fixed and processed for sectioning. The cells shrink but remain attached to each other by desmosomes giving the cells a "spiny appearance".
Stratum granulosum is a layer just above the spinosum in which large amounts of keratohyalin is being synthesized. Granules of this basophilic protein can be seen in stained sections.
Stratum lucidum - The keratinocytes in this layer are filled with keratohyalin and a fibrous protein, keratin. Keratin is tough, durable and water resistant. Keratin is also the chief component in hair and nails.
Stratum corneum is the outermost layer of the epidermis composed of flattened, dead, keratin-filled cells. These dead cells are constantly being flaked off and replaced from below by cells dividing in the germinativium. This dead layer provides protection from abrasion, strong chemicals, microbial invasion and dehydration.
B. Other cell types in the epidermis include:
Langerhans cells are T lymphocytes (cells that mount an immune response) located within the stratum spinosum. These cells will initiate an immune response against microbes and epidermal skin cancers.
Merkel cells are located among the cells of the germinativium. They are sensitive to touch.
Melanocytes are also located in the germinativium often under the basal cells just above the basement membrane. They manufacture a brown pigment called melanin. Melanin is packaged within vesicles called melanosomes in the cytoplasm of the melanocytes. These vesicles are transferred into the overlying keratinocytes, darkening the skin. Melanin is a helpful material in the skin. It tends to surround the nucleus of the keratinocyte protecting the DNA of that cell from damage due to ultraviolet light from the sun. It also seems to neutralize damaging chemicals called free radicals that accumulate in traumatized tissues. Cancer of the melanocytes, melanoma, is an extremely dangerous and malignant neoplasm.
Changes in Human Skin Color
Tanning Effect – see previous comments concerning the action of melanocytes.
Reddening of skin occurs due to an increased blood flow in the underlying dermis. The increasedblood flow may be caused by:
The release of the vasoactive chemical Histamine due to trauma in the skin (inflammation).
An increase in body temperature which leads to a vasodilation of blood vessels in the dermis. Strong emotional states will lead to an increase in blood flow in the dermis.
3. Blanching of Skin ("turning pale") occurs due to decreased blood flow to the skin. This decreased blood flow may be caused by:
A sudden drop in blood pressure – shock. Hypothermia Emotional states – fear, panic.
4. Cyanosis – bluish color in skin due to sustained reduction in blood supply to the skin. Hemoglobin in blood becomes depleted of oxygen and appears blue through the layers of skin.
5. Jaundice – When liver function is interrupted due to cirrhosis, liver cancer or blockage of bile flow, yellow bile pigments and bilirubin accumulate in the skin and whites of the eyes.
6. Tumor of the pituitary gland or Addison’s disease leads to an over production of melanocyte stimulating hormone (MSH). MSH darkens the skin.
7. Vitiligo – In this condition an individual loses their melanocytes. It is thought to be due to an autoimmune disease in which the immune system mistakenly attacks and destroys the body’s melanocytes.
Bugs Alive
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Post by susiebelle on May 30, 2005 20:35:48 GMT -5
This is a little it off subject but, I have experienced the upper part of my body dripping with sweat while my feet and lower legs ar freezing. Can anyone explain this? It has happened when I am sitting and when I'm up and moving around. I have also noticed my feet and ankles change from white to blue and sometimes greenish black. I don't have varicose veins or high bloodpressure. A couple of times I had a stinging sensation in my leg around the knee area and then a big bruise appeared. Any info would be appreciated.
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Post by adapted on May 31, 2005 3:09:44 GMT -5
Susiebelle, I don't see that you've mentioned any swelling in your legs and feet, but even so, it sounds as though you could have a circulatory problem. Lower back problems can also cause symptoms, but the stinging, and bruising, sounds to me like a broken vein, or maybe, a minor, superficial blood clot. I don't know about the profuse upper body perspiration, other than knowing that some menopausal ladies experience symptoms such as that. Sorry I can't be of any better assistance, but maybe others will see your post and have your answers. I'd recommend seeing a doctor. Good Luck & God Bless You
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