Forensic Extracts by Dr. Sunil Duchania

  Crime Scene Investigation The crime scene investigation is based upon certain principles and procedures. The crime scenes are inconsistent and based upon their diversity, crime scenes can be classified as follows: The site of the first criminal activity is the primary crime scene and any later crime scenes are the secondary crime scenes. Objectives: To find the sequence of events, decide the mode of operation, to find out what all the criminals may have done, to recover physical evidence from the scene of crime. Every effort should be undertaken to preserve the crime scene as Locard’s exchange principle states that when­ever an object meets another, there is an exchange of material between them. This implies that traces from the scene can be continued the body or tools of the criminal and traces from any of these may be left at the scene. Steps of the Crime Scene Investigation 1.        Find Scene Dimensions. 2.        Establish Security 3.        Create a Plan & Co

  Surrogate birth Surrogate birth means hiring of another woman who is artificially inseminated with the barren woman’s husband’s sperms and is called the surrogate. When the child is born, he is handed over to the biological father and his wife. Usually, it is the surrogate who is biological as well as gestational mother of the child but when the wife’s ovum is fertilized with the husband’s semen in the labo­ratory and then implanted in the surro­gate, she remains only the gestational mother. A surrogate is a woman who conceives, carries, and gives birth to a child for another person or couple (intended parent/s). Altruistic surrogacy: It involves no monetary compensation to the surrogate mother other than the medical expenses and insurance coverage during the pregnancy. Commercial surrogacy: It includes surrogacy or its related procedures undertaken for a monetary benefit or reward (in cash or kind) exceeding the basic medical expenses and insurance coverage. Indications:

  Artificial insemination Artificial insemination is a process when the sperms are deposited in the female genital tract artificially when the female cannot conceive through the sexual intercourse with her husband. The sperms may be introduced in the cervical canal or inside the uterus . Less common techniques are intrafallo­pian and intraperitoneal insemination when the sperms are placed near the mouth of the fallopian tube and ovaries, respectively. Indications:   (i) Incurable defects in the husband’s semen rendering him incapable of procreation.   (ii) Premature or retrograde ejacu­lation.   (iii) Hereditary disease in the husband as to contraindicate paternity.   (iv) Rhesus incompatibility resulting in failure of children to survive because of erythroblastosis foetalis and husband being homozygous rhesus positive (v) When the hus­band is impotent making sexual intercourse impossible (vi) Abnormalities of penis such as epispadias or hypospadias etc. (vii) When the h

  Toxic Honey (mad honey):  Honey produced from the nectar of Rhododendron ponticum contains alkaloids that can be poisonous to humans, while honey collected from Andromeda flowers contains grayanotoxins, which can cause paralysis of limbs in humans and eventually leads to death. Grayanotoxin is derived from the leaves, twigs, or flowers of rhododendron and also from secondary products such as honey. It is the latter that has brought attention to this natural toxin as there are many reported cases of poisoning due to ‘mad honey.’ Many plants like Rhododendron, Pieris, Agarista and Kalmia, contain diterpene grayanotoxins. Consumption of grayanotoxin containing honey may result in intoxication specifically characterized by dizziness, hypotension, and atrial-ventricular block. Mechanism of action:   Symptoms are caused by an inability to inactivate neural sodium ion channels resulting in continuous increased vagal tone. Grayanotoxin only binds to the activated conformation of sodium

  Phosphorus Phosphorus is used in the manufacture of matches, fireworks, rodenticide, and fertilizers. Three forms of phosphorus are available white, red, and black. Yellow phosphorus is formed by a small amount of red phosphorus resulting discoloration of white phosphorus. Mechanism of action: It affects cellular oxidation, and it is highly corrosive and is also a general cellular poison. Cardiovascular collapse occurring after ingestion results not only from fluid loss caused by vomiting and diarrhea but also from a direct toxic effect on the heart and vascular tone. Sign and symptoms: Ingestion of elemental white or yellow phosphorus typically causes severe vomiting and diarrhea, having a garlic-like odor. Other signs and symptoms of severe poisoning are dysrhythmias, coma, hypotension, and death. It can also cause liver become swollen, fatty, and soft suggestive of acute liver atrophy etc. Fatal dose: 60-120 mg Fatal Period: 2-8 days Treatment: Gastric lavage using

  Ergot Ergot is dried sclerotium of the parasitic fungus claviceps purpurea that grows on cereals like wheat, rye, oat, barley and bazra etc. The spores of ergot contaminate the grains through insects or wind.   The spores then replace the grain and form dark purplish bodies larger than the original grain.     Dried sclerotium of the ergot   Alkaloids Amino-acid alkaloids (i) Ergo­toxine (ii) Ergotamine Lysergic acid and amino-alkaloids (i) Lysergic acid (ii) Lysergic and diethylamide Mechanism of action: Ergot acts on smooth muscles of intestine, uterus and arterioles and it is commonly used in obstetrics for its ecbolic action. It is also used in the treatment of migraine, as aborti­facient and in veterinary practice. Ergot derivatives directly stimulate vasoconstriction and uterine contraction, antagonize alpha-adrenergic and serotonin receptors, and may dilate some blood vessels via a CNS sympatholytic action. Signs and Symptoms   (i) Dryness and irritation of th

  Sulphuric acid (oil of vitriol) It is colourless with no fumes and it chars and blackens the skin. Sign and symptoms: Pharyngeal pain is the most common presenting symptom. There will be intense burning pain in mouth, throat, oesophagus and up to the stomach. Dribbling of acid mixed with saliva on the angles of mouth and chin causing corrosion and brownish discolouration of skin over angles of mouth, chin and over the chest. Frothy eructation, retching and vomiting; vomited matter is acid, contains blood, mucous and shreds of mucous membrane Oral cavity: Mucosa of mouth and lips are softened, excoriated, corru­gated and cove­red with dirty white necrotic mem­brane that assumes brownish black discolouration. Tongue is swollen, excoriated and dis­coloured with white coating that becomes dark later. It may get disorganized in to a shapeless, pulpy mass. Teeth are dead chalky white deprived of polish; Breathing is difficult and noisy due to swollen and inflamed fauces and tender

  Traumatic Brain Injuries (TBI):  The injury can be penetrating, such as a gunshot wound, or a non-penetrating injury, such as being struck in the head in a car accident. Anyone can experience a TBI, although nearly 80% of them happen to males. TBIs are also more common among older people. The severity of the head injury is decided by several different factors, such as loss of consciousness, certain neurological symptoms that happened at the time of the injury, loss of memory for the injury and time surrounding it, and abnormalities on head CT or brain MRI. Diffuse axonal injury is the shearing (tearing) of the brain's long connecting nerve fibers (axons) that happen when the brain is injured as it shifts and rotates inside the bony skull. DAI usually causes coma and injury to many different parts of the brain. The changes in the brain are often microscopic and may not be clear on computed tomography (CT scan) or magnetic resonance imaging (MRI) scans. On microscopic examinatio