1 / 19

CHROMATOGRAPHY

BIOCHEMISTRY

mprasadnaidu
Download Presentation

CHROMATOGRAPHY

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. IRON M.Prasad Naidu MSc Medical Biochemistry, Ph.D,.

  2. Iron (Fe) • 2 types of body iron • heme iron • hemoglobin, myoglobin, catalases, peroxidases, cytochromes (a, b and c – involved in electron transport), cytochrome P450 (involved in drug metabolism) • non-heme iron • ferritin, hemosiderin, hemofuscin, transferrin, ferroflavoproteins, aromatic amino acid hydroxylases • food iron is also classified as heme and non-heme

  3. Food iron heme iron • meats • poultry • fish 20-23% of heme-iron is absorbable non-heme iron • vegetables • fruits • legumes • nuts • breads and cereals only ~ 3% on non heme iron is absorbed

  4. Iron absorption • occurs in upper part of small intestine • about 10% of food iron is absorbed • requires gastric HCl (releases ionic iron) • also requires copper • ferrous is better absorbed than ferric form • Fe++ forms chelates with ascobic acid, certain sugars and amino acid

  5. Iron distribution and storage • carried in blood stream via transferrin (a b globulin) • stored in 2 forms: • ferritin (a water soluble complex consisting of a core of ferric hydroxide and a protein shell (apoferritin) • hemosiderin (a particulate substance consisting of aggregates of ferric core crystals) • stored in liver, spleen, bone marrow, intestinal mucosal cells and plasma

  6. Iron elimination • there is no mechanism for excretion of iron • iron is normally lost by exfoliation of intestinal mucosal cells into the stools • trace amounts are lost in bile, urine and sweat (no more than 1 mg per day) • bleeding (vaginal, intestinal) is a more serious mechanism of elimination

  7. IRON DEFICIENCY Initial symptoms are vague and ill-defined • easy fatigability • lack of appetite • headache • dizziness • palpitations then: hypochromic-microcytic anemia • microcytosis (small RBCs) • hypochromia (poor fill of hemoglobin) • poikilocytosis (bizarre shapes) • anisocytosis (variable sizes)

  8. IRON DEFICIENCY Causes: • excessive blood loss (parasitic, accidental, menstrual): is most common cause • rapid growth in children with limited intake of iron • malabsorption • gastric resection • sprue • increased metabolic requirement • pregnancy, lactation or neoplasia

  9. Diagnosis of iron deficiency • hematology (microcytic hypochromic cells) • low serum iron • low serum ferritin( indicates low body stores) • in some conditions (inflammation, hepatitis) ferritin may be high • low hemosiderin • high total iron binding capacity (TIBC)

  10. Iron absorption • average diet contains 10 - 15 mg of iron perday • a normal person absorbs 5 -10% of this iron or 0.5 - 1.0 mg daily • iron absorption increases in response to low iron stores • menstruating women: 1 - 2 mg per day • pregnant women: 3 - 4 mg per day • absorption is via active process

  11. Different types of iron • Ferrous sulfate 20% • Exsiccated ferrous sulfate • ferrous gluconate 11.6% • ferrous fumarate 33% • ferrocholinate 12% • polysaccharide-iron complex • iron dextran (Imferon)

  12. Treatment of iron deficiency • give 200 - 400 mg of iron per day • up to 25% of the iron preparation may be absorbed • 50 - 100 mg of iron may be utilized in case of deficiency • give on an empty stomach • enteric coated iron tablet should not be used since we want absorption to occur in the stomach and proximal duodenum

  13. Treatment of iron deficiency • parenteral iron is used in patients who have had bowel resections or in cases of inflammatory bowel disease • normally given IM (painful) Z-track minimizes tatoo • oral iron causes black stools, constipation, cramping • do not administer with antacids or metal chelators (tetracyclines)

  14. Acute iron toxicity common in small children ingesting large doses of soluble iron compounds toxicity is usually divided into 4 phases: 1. 30 - 60 min. following ingestion • abdominal pain • nausea and vomiting • signs of acidosis and cardiovascular collapse may be seen

  15. Acute iron toxicity 2. Period of improvement - last about 8 to 16 hours 3. Period of progressive cardiovascular collapse (about 24 hrs after ingestion) • convulsions • coma • high mortality 4. Gastrointestinal obstruction from scarring of stomach and small intestine

  16. Deferoxamine mesylate (DFOM) A chelating agent which reacts with ferric ion to form a 1:1 chelate known as ferrioxamine Marketed as Desferal Injection (Ciba) Produced by Streptomyces pilosus

  17. Chronic iron toxicity • causes • hereditary hemochromatosis • hemosiderosis • symptoms • cirrhosis: iron deposition in the liver • diabetes: iron deposit in the pancreas (damage to beta cells) • skin pigmentation • cardiac failure • treatment: phlebotomy ( 1 unit of blood removes about 250 mg of iron

  18. THANK YOU

More Related