Blood History

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Blood History

• Different blood types were recognized in 1875,
  but it wasn't until 1901 that Karl Landsteiner
  named and standardized the groups.
• In 1940, Landsteiner also discovered the rhesus
  factor in blood, labeling it Rh if the antigen
  was present in the red blood cells and Rh- if
  not. 
• Today, blood typing also includes different types
  of enzymes and proteins that perform specific
  activities in the body, which helps to
  individualize the blood.  (More than 150 serum
  proteins and 250 cellular enzymes have been
  isolated, as well as many more antigens

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What is in Blood?

• The three types of cellular elements in the blood
  are erythrocytes (red blood cells), leukocytes
  (white blood cells), and platelets.
• Plasma is the other portion that is in blood.

3
What is in Blood

• The plasma is the liquid part of the blood, which
  is 90 water. The other 10 contains proteins,
  waste products, gases, and nutrients.
• Plasma makes up 55 of blood.

4
Blood Volume

• On average, accounts for 8 of total body
  weight- 5 to 6 liters of blood for males
• 4 to 5 liters of blood for females
• A 40 percent blood volume loss, internally or/and
  externally, is required to produce irreversible
  shock (death).
• A blood loss of 1.5 liters, internally or
  externally, is required to cause incapacitation

5
Red Blood Cells

• Red Blood Cells transport oxygen on molecules
  called Hemoglobin.
• Erythropoiesis is the production of new red
  cells.
• They are made at 2-3 million a second.
• Average lifespan is 120 days.

6
White Blood Cells

• Leukocytes are the mobile units of the bodys
  immune system. They are also called white blood
  cells.
• They defend against the invasion of pathogens.
• They identify cancer cells.
• They remove the bodys litter by phagocytosis.
• They can leave the circulation and go to the
  sites of invasion and tissue damage.
• There are five kinds of leukocytes.
• 5-10 million/ml of blood normal.

7
Platelets

• They remain functional for about 10 days.
• 1/3 stored in spleen
• 250 million/ml of blood
• They begin the clotting to a wound.

8
Blood Typing

• Red blood cells carry a substance called an
  antigen, which produces antibodies to fight
  infection, and several different types.
• Types of A, B, O. This is based on which antigen
  is present and which is absent.

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Blood Typing

• RH factor is an antigen on blood that may or may
  not be on the red blood cell. It is labeled as
  or -.
• Rare blood types exist in addition to the basic
  ABO system.

10
Blood Types and Race

• The "O" type is most common among indigenous
  people (like Aborigines and Native Americans) and
  Latin Americans. 
• The "A" type is most common among Caucasians and
  those of European descent.
• The "B" type is most common among
  African-Americans and certain Asians (e.g.
  Thai).  The "AB" type is most common among the
  Japanese and certain Asians (e.g. Chinese). 
• An interesting phenomenon is that Middle
  Easterners are somewhat likely to have nucleated
  red blood cells, whereas normally, red blood
  cells contain no nucleus .

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Blood Forensics

• Determination of the type and characteristics of
  blood, blood testing, bloodstain examination, and
  preparation of testimony or presentations at
  trial are the main job functions of a forensic
  serologist, who also analyzes semen, saliva,
  other body fluids and may or may not be involved
  with DNA typing.
• Blood is the most common, well-known, and perhaps
  most important evidence in the world of criminal
  justice today.
• There's no substitute for it, whether for medical
  or forensic purposes. Its presence always links
  suspect and victim to one another and the scene
  of violence. 

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Blood Presence Determination

• The first test is simply the use of a powerful
  light moved across every surface of a crime
  scene.  That yields possible traces for visual
  inspection.
• If nothing is seen, but there is reason to
  suspect blood had been present, a chemical called
  luminol is sprayed across the scene because it
  reacts to blood by making it luminescent.  It
  only takes about five seconds.
• There is one problem with this test luminol can
  destroy the properties of the blood that
  investigators need for further testing.
• The Kastle-Meyer Color Test uses a solution of
  phenolphthalein and hydrogen peroxide on a piece
  of filter paper, and when blood of any quantity
  is present, it turns pink

13
Blood in the Courtroom

• Bloodstain patterns tell a lot about position and
  movement during the crime, who struck whom first,
  in what manner, and how many times.
• This destroys most alibi and self-defense
  arguments for crime, and at the very least, trips
  most suspects up in their explanation of what
  happened.

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Blood Forensics

• When a darkish substance is found at a crime
  scene, it must first be determined to be blood.
• There are several testspresumptive tests used
  strictly for screening---that will differentiate
  between blood and other substances

15
Animal versus Human

• Investigators use the precipitin test to
  determine whether the blood is of animal or human
  origin. In summary, rabbit serum is combined with
  the sample and if there is a reaction then it is
  human blood.
• Animals have different antigens than humans do.

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Blood Forensics

• After determining that the blood is human,
  analysts can go ahead and determine blood type
  with an ABO test, and then work on the gender of
  the person from whom the blood came.
• These days, thanks to discoveries in 1985, DNA
  technology has replaced the tests for specific
  enzymes and proteins. 
• It's more accurate to match DNA from a blood
  sample at a crime scene to a source than to draw
  up an entire blood profile

17
Blood Loss History

• Blood may be dripped out, sprayed from an artery,
  oozed out through a large wound, or flung off a
  weapon raised to strike another blow. 
• In the 1930s, Scottish pathologist John Glaister
  classified blood splashes into six distinct
  types
• Drops on a horizontal surface
• Splashes, from blood flying through the air and
  hitting a surface at an angle
• Pools around the body, which can show if it's
  been dragged
• Spurts from a major artery or vein
• Smears left by movement of a bleeding person
• Trails, either in form of smears when a bleeding
  body is dragged, or in droplets when it is
  carried

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Blood Pattern Forensics

• Blood pattern analysis plays an important role in
  the reconstruction of many crime scenes.
• The various types of bloodstains indicate how the
  blood was projected from the body via several
  factors
• Type of injuries
• The order in which the wounds were received
• Whose blood is present
• The type of weapon that caused the injuries
• Whether the victim was in motion or lying still
  when the injury was inflicted
• Whether the victim was moved after the injury was
  inflicted
• How far the blood drops fell before hitting the
  surface where they were found.

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Blood Drop Forensics

• The shape of a blood drop can reveal a lot about
  the conditions in which it fell.
• Examples
• If blood falls a short distance--around twelve
  inchesat a 45-degree angle, the marks tend to be
  circular. 
• If blood drops fall several feet straight down,
  the edges may become crenellated, and the farther
  the distance from the source to the surface, the
  more pronounced the crenellation. 
• A height of six feet or more can produce small
  spurts that radiate out from the main drop. 
• If there are many drops less than an eighth of an
  inch across, with no larger drop, then it may be
  concluded that the blood spatter probably
  resulted from an impact.
• If the source was in motion when the blood leaked
  or spurted, or if the drops flew through the air
  and hit an angled surface, the drops generally
  look like stretched-out exclamation marks.  The
  end of the stain that has the smallest size blob
  indicates the direction in which the source was
  moving. 

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Surface Tension

• The elastic like property of the surface of the
  liquid that makes it tend to contract, caused by
  the forces of attraction between the molecules of
  the liquid.The cohesive forces tend to resist
  penetration and separation.

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Passive Blood Stains

• Passive Bloodstains are drops created or formed
  by the force of gravity acting alone.
• Types drips, drops, pools, and clots

22
Transfer Bloodstains

• A transfer bloodstain is created when a wet,
  bloody surface comes in contact with a secondary
  surface.
• Types smear, wipe, smudges

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Projected Blood Stains

• Projected bloodstains are created when an exposed
  blood source is subjected to an action or force,
  greater than the force of gravity. (Internally
  or Externally produced)
• The size, shape, and number of resulting stains
  will depend, primarily, on the amount of force
  utilized to strike the blood source.

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Types of Projected Blood Stains

• Arterial Spurt
• Cast-off Stains
• Impact Slatter

25
Impact Angle Determination

• These are found by using math formulas measuring
  angles. For Example

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• http//nobelprize.org/educational_games/medicine/l
  andsteiner/index.html
• This site is in MHS Science called Blood Type
  Game
• Go there, play the game, take notes on blood
  typing so you can run tests on the Lois McArthur
  suspects.

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