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ID & Characterization of Blood & Bloodstain
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BEFORE DNA THERE WAS: SEROLOGY
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Serology examination & analysis of body fluids
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Serology STAINS often deteriorated and degraded
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Serology Correct steps must always be followed - PROTOCOL
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Blood Facts The average adult has about FIVE liters of blood inside of their body, which makes up 7-8% of their body weight. Blood is living tissue that carries oxygen and nutrients to all parts of the body, and carries carbon dioxide and other waste products back to the lungs, kidneys and liver for disposal. It also fights against infection and helps heal wounds, so we can stay healthy. There are about one billion red blood cells in two to three drops of blood. For every 600 red blood cells, there are about 40 platelets and one white cell. http://www.bloodbankofalaska.org/about_blood/index.html
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Presumptive testing Negative result questioned stain is not likely blood Positive result questioned stain is likely blood
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Presumptive Screening Tests Presumptive tests produce a color reaction or release of light Tests rely on hemoglobin presence
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Catalytic Color Test Sample a stain with a clean, moist cotton swab Add a drop of reagent Add a drop of hydrogen peroxide Color will develop immediately
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Catalytic Color Test Examples: Benzidine Alder – blue-dark blue Phenolphtalein-Kastle-Mayer Test – pink O-Tolidine test – blue Leucomalchite Green (LNG) – green Tetramethylbenzidine- Hemastix – green –blue green
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CHEMILUMINESCENCE light is emitted as a product of the chemical reaction
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FLUORESCENCE light is emitted when a substance is exposed to a shorter wavelength of light
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Chemiluminescence & Fluorescence More sensitive than color tests May damage blood stain (no blood/DNA typing) Used to locate and define areas of blood old blood stains cleaned floor
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LUMINOL Method similar to color test combined with oxidant and sprayed over area thought to contain blood Emits a blue-white to yellow green glow Extremely sensitive – 8 paint layers
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FLUORESCEIN combined with oxidant and sprayed over area thought to contain blood Fluoresces when treated with a UV light includes a thickener makes it more effective on vertical surfaces Study showed no interference with DNA analysis
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Confirmatory test for Blood Confirms presence of blood Several test use crystal formation to detect hemoglobin 2 types of tests Teichmann test Takayama test
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SPECIES ORIGIN Most methods test for serum proteins Serum proteins are found in all animals, but are slightly different Species ID methods based on antigen/antibody interactions
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Microscopic Views Bird Blood Cat Blood Dog Blood Fish Blood Frog Blood Snake Blood Human Blood Horse Blood
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GENETIC MARKERS IN BLOOD If a stain is blood, and it is human blood, then whose is it? Blood Group Markers Protein/Enzyme Markers DNA
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Blood Group Markers ABO Markers Lewis System Rhesus System Many blood group markers, including:
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Genetic Markers in Blood Your blood group is genetically controlled and a lifelong characteristic Types of markers Antigen Marker Protein Marker Enzyme Marker
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BLOOD GROUP MARKERS ABO MARKERS Look at antigens on Red Blood Cells antigens are glycoproteins are attached to outside of cell
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Introduction to Blood ABO blood groups found on outside of cell
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Blood Group Markers ABO Markers (antigen and antibodies) person will have antibodies (A or B) to whatever blood group he/she doesn’t have Otherwise, a persons blood would clump up and cause death
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Blood Group Markers ABO Markers (antigen and antibodies) Blood Type Antigen (blood group) Antibody % population A B AB O
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Blood Group Markers ABO Markers (antigen and antibodies) Blood Type Antigen (blood group) Antibody % population AAAnti-B40 B AB O
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Blood Group Markers ABO Markers (antigen and antibodies) Blood Type Antigen (blood group) Antibody % population AAAnti-B40 BBAnti-A10 AB O
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Blood Group Markers ABO Markers (antigen and antibodies) Blood Type Antigen (blood group) Antibody % population AAAnti-B40 BBAnti-A10 ABA & Bnone5 O
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Blood Group Markers ABO Markers (antigen and antibodies) Blood Type Antigen (blood group) Antibody % population AAAnti-B40 BBAnti-A10 ABA & Bnone5 OHAnti-A & Anti-B 45
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BLOOD GROUP MARKERS ABO MARKERS Testing is similar to species test An anti-A, anti-B, or anti-AB antiserum (containing antibodies) is reacted with blood stain to detect blood cells A, B, or AB blood cells are reacted with blood stain to detect antibodies
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BLOOD GROUP MARKERS ABO MARKERS Tests can get complicated with absorbing and releasing cells Final step is usually testing for agglutination (blood clumping)
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BLOOD GROUP MARKERS ABO MARKERS A cells clump with anti-A B cells clump with anti-B AB cells clump with both O cells do not clump
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How common is your blood type?
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Rh Factors Scientists sometimes study Rhesus monkeys to learn more about the human anatomy because there are certain similarities between the two species. While studying Rhesus monkeys, a certain blood protein was discovered. This protein is also present in the blood of some people. Other people, however, do not have the protein. The presence of the protein, or lack of it, is referred to as the Rh (for Rhesus) factor. If your blood does contain the protein, your blood is said to be Rh positive (Rh+). If your blood does not contain the protein, your blood is said to be Rh negative (Rh-). A+ A- B+ B- AB+ AB- O+ O- http://www.fi.edu/biosci/blood/rh.html
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Blood Transfusions A blood transfusion is a procedure in which blood is given to a patient through an intravenous (IV) line in one of the blood vessels. Blood transfusions are done to replace blood lost during surgery or a serious injury. A transfusion also may be done if a person’s body can't make blood properly because of an illness. Who can give you blood? People with TYPE O blood are called Universal Donors, because they can give blood to any blood type. People with TYPE AB blood are called Universal Recipients, because they can receive any blood type. Rh + Can receive + or - Rh - Can only receive - Universal Donor Universal Recipient
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