Transcript MEDICOLEGAL ASPECTS OF BLOOD AND OTHER STAINS [PPT]
Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Blood Seminal fluid Vaginal discharge Saliva Faecal stain Urine Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Main cellular content RBC – Haemoglobin which possess peroxidase activity Haemoglobin and other proteins of blood has antigenic properties – produces antibodies when injected into animals Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
May establish a link between offence, offended and offender May establish link between offence and offensive agent Fictitious charges by presenting an animal stain as human In poisoning, poison chemically detected Time since death may be estimated by chemical and enzymatic study Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
• • • • • Whether the stain is actually a blood stain Physical Chemical Microscopic Spectroscopic Micro chemical Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
• Whether the blood stain is of human or other than human Precipitin test If human, which blood group Sex, source Indication as to cause of death Whether belong to victim or accused Whether bleeding antemortem or postmortem Any disease process Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Vegetable stains
ammonia greenish yellow color Bleached by chlorine water M/E vegetable cells and fibers
Rust stains
Does not fall off in scale on being heated Positive reaction for iron Dissolved in dil. Hcl Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Mineral stains Synthetic dye stains
Nitric acid
yellow
strong alkali original color
Other stains
Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Highly sensitive Positive reaction even with faint traces of blood Principal factor – peroxidase activity liberating nascent oxygen which leads to colour change Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
1.
BENZIDINE TEST stain extract ┼ benzidine ┼ 10 vol in hydogen peroxide glacial acetic acid
Blue colour
Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
2.
KASTLE MAYER TEST 3.
Phenolphthalein in alkaline medium Pink colour ORTHOTOLIDINE TEST (4% orthotolidine in ethyl alcohol)+ glacial acetic acid + H 2 O 2 Green colour 4.
5.
LEUCHOMALACHITE GREEN TEST Bluish green colour LUMINAL TEST Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
RBC’s- confirmatory Species Sex Disease Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
HAEMIN CRYSTAL TEST/ TEICHMAN’S TEST Sod. Chloride + strain extract + glacial acetic acid
Yellowish brown rhombic crystals of haemin
HAEMOCHROMOGEN CRYSTAL/ TAKAYAMA TEST takayama reagent + stain extract
Salmon pink hemochromogen crystals
Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Detects blood where RBC structure is lost and hemoglobin has undergone chemical composition Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
PRECIPITIN TEST When human serum is injected in an experimental animal, antibodies develop.
When any human serum is brought in contact with this animal serum, the antibodies and protein will react and a visible precipitate will develop Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
- Barr bodies in > 3% of polymorphs - Y chromosome is fluorescent to quinacrine Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
• Blood grouping red cell antigen • White cell antigen • Se protein polymorphism • Red cell enzyme polymorphism Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
ABO system Rh system MNSs group system Lutheran Duffy Lewis Kidd Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Agglutinogens in water soluble form Secrete ABO antigens into body fluids and secretions Agglutinogens in lipoidal form Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
Human Leucocyte Antigen (HLA)- the MHC in humans Present on Chromosome 6 and encode cell surface antigen presenting proteins 4 types – HLA-A, HLA-B, HLA-C, HLA-D Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
• • • Occurrence in the same population of two or more alleles at one locus, each with appreciable frequency, where the minimum frequency is taken as 1% Se. proteins subject to genetic variation are Se. haptoglobins Se lipoproteins Abnormal haemoglobins Dr. Shiuli, Forensic Medicine & Toxicology, KGMU
• • > 250 proteins & enzymes found in red cell Established value in paternity testing Phopho glucomutase Adenylate kinase Dr. Shiuli, Forensic Medicine & Toxicology, KGMU