Saliva and saliva spot inspection

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Transcript Saliva and saliva spot inspection

Saliva and saliva spot
inspection
钟树荣(PhD,副教授)
昆明医科大学法医学院
Cell Phone:18213823198
E-mail:[email protected]
What are the objects found saliva stain easily
?
bite mark
一、The characteristics of the
saliva and saliva stain
• (一)、saliva
• (saliva) is secretion of the salivary glands,
saliva is colorless, tasteless, and is close
to neutral liquids.
water (99.4%)
无机
物质
Sodium, potassium, chloride, calcium
Phosphoric acid
Carbonic acid
rhodanic acid
saliva
Blood type thing
有机
物质
Mucin, ball eggs
Amino acids, urea, urine
淀粉酶
麦芽糖酶
• Fall off in addition, the saliva and oral
mucosa epithelial cells, a large number of
bacteria, a small amount of white blood
cells, and food scraps, etc
(二)、Saliva spot
• Saliva stain is saliva drying after the
formation of the spot mark, saliva spot is
more common in forensic inspection of
one of the biological material inspection
• Saliva spot on a white background with
pale yellow, Pale blue fluorescence under
ultraviolet light
二、Saliva and saliva spot inspection purpose
个人识别
(Individual Identification)
亲权鉴定
(parentage testing)
Confirm the saliva spot
三、Saliva
stain proof
Confirm whether or not
Saliva spot
Salivary amylase Check
out the test
Fall out of the oral mucosa
epithelial cells Check out the test
(一)、Saliva amylase detection test
Starch iodine turned blue
theory
iodine
starch
Flecked leaching liquid
The same blue
Change the blue
氯化三苯基
四氮唑
In the spot amylase
碱性铜
Prove the existence
of sugar
In the spot amylase
matters need attention
Flecked unchanged leaching liquid
reaction with starch and iodine blue, can
only prove flecked contains amylase,
doesn't mean the blackspot is saliva.
(二)、Fall off oral mucosal epithelial cells of the inspection
cell membrane
Flat, polygons, the
shape is not very regular
Cytoplasm
nucleus
HEDyeing
Acid fuchsin methylene blue staining
Cell membranes are
thin, coloring shallow in the
cell membrane is the
cytoplasm, dyed deep
shape larger is the nucleus.
attention:
Because saliva spot check material often appear in People's Daily
supplies Or items, such as cups, cigarette butts, stone, etc., so
confirmed Saliva after the spot, can be directly used to identify
the individual, don't have to Species identification.
But when determining the bite of saliva spot, first
of all want to make sure Is a person or animal bites.
四、Saliva of personal identification
Determination of saliva secretion spot ABO blood group
and the state
Polymorphisms of proteins and enzymes in saliva spot
detection
Sex identification of saliva
Saliva of DNA polymorphism analysis (individual identification, paternity test)
Carrier Type
DNArelative
amount
About the data
Fresh saliva
many
0.8ug/ml
Sterile
physiological
salt Water
gargle water
more
1.5ug/ml
Saliva swabs
few
0.26ug/cm2
Saliva spot
less
0.16ug/cm2
cigarette end
less
12-120ng/个
The PCR technology can enlarge the existing DNA is extremely
limited to 2 ng, Reason for common saliva (spot) for examination for
DNA testing is absolutely Practical and feasible.
The extraction of DNA specimens
1.
Biological samples and the
separation
of
biological
components (carrier)
2.
DNA extracted from cells
and
cells
components
概述
with
other
How to obtain nuclear
DNA ?
summarize
Raw material cells
SDS
hypotension
Nuclear DNA extraction principle
nucleus
SDS
Heated to boil
Nuclear membrane rupture, released
from within the nuclear DNA
Proteinase
Hydrolysis of DNA binding proteins,
DNA free in solution
Magnetic beads,
silica gel
Phenol and
chloroform, ethanol
Impurity removal, collecting
DNA
概述
The ideal DNA extraction
(1)Maximum remove the RNA in the sample DNA solution,
the composition such as proteins, polysaccharides
and lipids molecules;
(2)As
far as possible keep the integrity of the extracted
DNA molecules;
(3) to reduce or eliminate the possible of enzyme inhibition
substances, such as organic solvents, detergents,
metal ions, and dyes, and other enzyme activity by
inhibiting DNA analysis.
summarize
五、Saliva and saliva of extraction
(1)、Fresh saliva collection :
First gargle, gauze or cotton swabs to be
included in the oral cavity, take out after soaking,
dry in ventilation places immediately cool,
package equipment inspection, respectively.
If gathering flow of saliva, because it
contains blood enzymes, shall be immediately
put in boiling water bath (bath boil 10 min)
inactivated enzyme type material.
(2). Saliva (spot) extract
on the site
Found at the scene of the
cigarette butts, paper towels,
cups, etc should be wearing
gloves or with tweezers
collection, packaging,
respectively.
 The scene suspected phlegm
article such as stains, skin and
bite marks, soaked with saline
water gauze wipe patches,
transferred to dry patches on
the gauze shade, mark
Second step transfer
method
• Key to the success of saliva spot transfer :
Drink or jelly contact people in the sales
process, the scene of the mug is not only the
criminals used, large area extraction line won't
work for sure. This requires inspection case
personnel should through the simulation
experiment in extraction for examination or normal
life habit that target area.
Several kinds of common carrier transfer of saliva
on the spot
With a handle mug
(1)pouring cup
Cup without handle
(2)Mineral water bottle
(3)butt
(4)Jelly shell
(5)bite mark
Generally associated with traces of saliva when occlusion, so it cannot be
ignored Wound saliva spot inspection. Found after a bite, use dry first Net
gauze to cover, to prevent pollution. Then wipe with two step method Pass
the effective components in saliva stain. Do not use hand before inspection
Wipe, also don't blot out drugs.
(6)Sunflower seeds
Due to the different people's habits, into hard seeds with shell on the
adhesion of the mouth How much cavity epithelium also will be different.
But according to the habits of most people , is to use teeth clacking, so it
contains relatively few components . Sunflower seeds in the fiber and has
strong adsorption, should not be so Should use the method of transfer cells,
direct access to the sunflower seeds. In addition, Sunflower seeds on the
surface due to contain pigments, add baking in the process of making And
have serious effects on amplification so using chelex extracted to The DNA
to do further purification and enrichment.
(7)Gum or coffee candy
Summary
Saliva and saliva spot inspection:
• perusal
• Saliva stain proof
(amylase,
shedding of the oral mucosa epithelial
cells)
• DNA polymorphism analysis (individual
identification and paternity tests)
• draw