Tag: HYT Module

Tumor Protein 53

TUMOR PROTEIN 53 (TP53)


TUMOR PROTEIN 53/TP53

INTRODUCTION:

  • One among “Tumor suppressor gene”.
  • A Phosphoprotein, barely detectable in nucleus of normal cells.
  • Also referred to as “Molecular policeman”/“Guardian angel of genome” 
    • Due to its protective role in cell cycle.
  • Hallmarks of cancer.
  • In non-stressed, healthy cells has short half-life~20 mins
    • Due to its association with MDM2.
    • MDM2 – Negative regulator of p53 tumor suppressor gene.

STRUCTURE:

  • Located on chromosome 17
  • Encodes d on gene TP53 coding 53k Da protein
  • Has seven domains.

FUNCTIONS:

1. Acts as “Tumor suppressor gene”.

  • Anti-cancer effects due to,
    • Enhances DNA repair, thus preventing mutations.
    • Activates quiescence (temporary cell cycle arrest).
    • Induces senescence (permanent cell cycle arrest).
    • Promotes apoptosis of genetically defective cells.

2. Effects of p53 on cell cycle:

  • Arrests cell cycle in G1phase by inhibiting Cyclin-Dependent Kinase (CDK).
    • Damaged DNA repairs during this time.
    • Normally when DNA damage is repaired by GADD45, p53 destructs itself & relieves cell cycle block.
  • If DNA is unrepaired, p53 along with activated BAX & BAK gene induces apoptosis.
    • Also induces senescence through LINC RNA.

3. Effects of p53 on cell repair:

  • On cell stress/injury,

DNA assaulted due to anoxia/inappropriate oncoprotein activity

DNA damage sensed by (ATM & ATR) protein kinases

Kinases phosphorylate p53 & liberate it from MDM2.

p53 accumulates & suppresses neoplastic transformation.

EFFECTS OF p53 MUTATION:

  • No cell cycle arrest.
  • No DNA repair.
  • Limitless replication leads to cancer.
  • Increases susceptibility to cancers 
    • Li-Fraumeni syndrome.
  • HPV encodes protein E6 binding to p53 thus, inhibiting its action.

Exam Important

  • p53 encodes 53k Da protein
  • p53 is located on Chr. 17
  • p53 arrests cell cycle at GI phase
  • Half-life of p53 protein in normal cells is 20 minutes
  • “Policemen gene’ or ‘Guardian gene’ is the name given to P53
  • P53 is the most common oncogene mutation causing malignancy in humans
Don’t Forget to Solve all the previous Year Question asked on TUMOR PROTEIN 53 (TP53)

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CNS DEPRESSANTS: Barbiturate poisoning & Chloral hydrate

CNS DEPRESSANTS: Barbiturate poisoning & Chloral hydrate


Barbiturate  poisoning

  • It  is  mostly  suicidal, sometimes  accidental.
  • Manifestations  are due  to  excessive  CNS  depression.
  • patient  is  flabby  and  comatose  with shallow  and failing  respiration  cyanosis.
  • fall  in  BP and  cardiovascular  collapse.
  • Renal shut  down,  pulmonary complications,  bullous eruption  (barbiturate  blisters).
  • Hypothermia ,  Finally  there  is  coma.
  • Individuals treated with drugs such as barbiturates show hypertrophy of the smooth endoplamic reticulum (ER) in hepatocytes

Important  specific  features  are

  • constricted  pupil (there  may  be  alternate  constriction and dilatation,  i.e. happus reaction).
  • liquid  gold  urine.

 Treatment  includes  :

  • Gastric  lavage
  • Haemodialsis
  • Supportive  measures (O2, assissed  respiration,  maintenance  of BP).
  • Forced  alkaline  diuresis.

Chloral Hydrate

  • Chloral  hydrate  is  a colourless,  crystalline  substance  having  peculiar  pungent  odor  and pungent bitter test.
  • It  is  a powerful  hypnotic in doses  produces  natural  sleep,  but in  larger  doses  depresses  CNS  and paralyses  vital centers.
  • It  is  given  in  food  or drink  to  make person  helpless,  called  knock out drops.
  • Mickey finn is  a  combination  of alcohol and chloral  hydrate.
  • Chloral  hydrate  is  also  called  dry  wine.

Exam Important

Barbiturate  poisoning:

  • patient  is  flabby  and  comatose  with shallow  and failing  respiration  cyanosis.
  • fall  in  BP and  cardiovascular  collapse
  • Hypothermia ,  Finally  there  is  coma.
  • Individuals treated with drugs such as barbiturates show hypertrophy of the smooth endoplamic reticulum (ER) in hepatocytes.

Chloral Hydrate:

  • crystalline  substance  having  peculiar  pungent  odor  and pungent bitter test.
  • It  is  given  in  food  or drink  to  make person  helpless,  called  knock out drops.
  • Mickey finn is  a  combination  of alcohol and chloral  hydrate.
  • Chloral  hydrate  is  also  called  dry  wine
Don’t Forget to Solve all the previous Year Question asked on CNS DEPRESSANTS: Barbiturate poisoning & Chloral hydrate

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Phosphorus Poisioning

Phosphorus Poisioning


PHOSPHORUS  POISONING:

  • Phosphorus is  a protoplasmic  poison  affecting  cellular  oxidation  and causing  anoxic  necorbiosis,  classically  affecting liver.  
  • It increases  fat  deposition  and  inhibits  glycogen  deposition  in  liver.  It is  used  in  fire  works  (Diwali  poisoning)  and as  rat  poison. Lethal dose  is  60-120  mg.
  • Earliar CuSO4 was used as an antidote for phosphorous poisoning.

Phosphorus  occurs  in  two  forms:

White/yellow phosphorus:

  • It  is  white,  and  becomes  yellow  on  exposure  to  air.  
  • It  is  translucent, luminous and  crystalline cylinders.
  • It has garlic like  odor. It is  insoluble  in  water  and  luminous  in  dark. 
  • Its  fumes  show  phosphorescence.

Red phosphorus:

  • It is  reddish  brown,  inert,  odourless  and  tasteless. 
  • It  is  nontoxic  (thus  poisoning  occurs  only  due to white phosphorus.
  • It is  put  on  the  sides  (striking  surface)  of match box  (along  with  powdered  glass).

Acute  poisoning

First stage: (GI  irritation): There  is  nausea,  vomiting,  diarrhea and  garlic odor.  This stage lasts  for  8 hours to  3 days.

Second Stage (Asymptomatic) : This  stage lasts  for  3 days.

Third  Stage:

  • There is liver  and  kidney  damage due  to  absorbed  phosphorus.
  • Initially  liver  is  enlarged  due  to  acute  fatty infiItration.
  • Later  liver  shrinks  due to  necrosis,  i.e.  Acute yellow atrophy.

Chronic  poisoning

  • Toothache  is  the  first  symptom  which  is  associated  with  loosening  of  teeth,  necrosis  of  gums  and osteomyelitis  of  jaw.
  • Therefore  chronic  phosphorus poisoning  is  also  known  as  Phossy  jaw or  glass  jaw.

Postmortem appearance

  • There is  garlic odor.  viscera  and  stool  glow in  dark  (due  to  luminosity).
  • To preserve  luminosity,  viscera  are  preserved  in  saturated  saline solution  Rectified  spirit  is  not  used  as it  causes loss  of Iuminosity.

Exam Important

  • Acute yellow atrophy.
  • liver  and  kidney  damage
  • Phossy  jaw or  glass  jaw.
  • There is  garlic odor.  viscera  and  stool  glow in  dark  (due  to  luminosity)
Don’t Forget to Solve all the previous Year Question asked on Phosphorus Poisioning

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Vegetables, Cantharides and Scorpion Poisons

Vegetables, Cantharides and Scorpion Poisons


VEGETABLE  POISONS

Abrus  precatorius  (Ratti)

  • Abrus  seeds  are odourless,  tasteless,  oval  (egg  shaped),  bright  red coloured  with a black spot at  one  pole.  They  contain abrin  a toxalbumin  as its  active  principle,  which  is  similar  to  viper  snake  venom.
  • Raw  or cooked  seeds,  when  swallowed  are  non-poisonous.  But  if  extract  is  injected  into  wound or under  skin, poisonous  symptoms  occur  which resemble  viper  bite.
  • This  method  is  used  to  poison  cattle’s  by means of needle,  known as sin needle.

Semicarpus anacardium (marking  nut  or  bhilawan):

  • Its seed  are  heart  shaped, conical  and black with acrid  oily  juice  which is  brownish  but  turns  black  on  exposure  to  air.
  • Active princiltles  are  semecarpol and  bhilawanol.
  • Juice applied  to  skin  produces  irritation,  painful  blisters  followed  by  itching  and  eczema.
  • Therefore  it  is  used to  produce artificial  bruises.
  • It is  also  used  by  washerman  to  mark clothes.

Croton  tiglium (jamalgota or  nepala)

  • It contains crotin, crotonoside,  cortonoleic  acid  and  methyl  crotonic  acid;  which  act as vesicating  resins  and  irritants.
  • It  produces  blisters  on skin and  sever  GI irritation  with  abdominal  pain,  vomiting  and  purging.
  • Fatal dose is  4-5 seeds or 1-2 ml (20  drops of  oil).
  • Fatal period  is  4-6  hours  (but  may be  upto  6 days). 

Cantharides (spanish fly  or  blister  beetle)

  • Cantharides  produces  a  poison  called  contharidin  which  has  following  effects  :
  • Skin: Local  inflammation  and blister  (vesicle)  formation.
  • If  ingested:  GI inflammation  with formation  of  blister  in  mouth and GI tract. This causes  burning  sensation  with intense  thirst, difficulty  in  swallowing,  blood  stained  vomiting  and  diarrhea.
  • Genitourinary  tract  inflammation:  Loin  pain, nephrotoxicity,  priapism,  and  engorgment  of vulva in  female.
  • Convulsion and  coma.

Scorpion poisoning

  • Haemolytic : If the scorpion has haemolytic venom, the symtoms of scorpion bite simulate the vasculotoxic snake (viper).
  • Neurotoxic : If the scorpion has neurotoxic venom, the symptoms of scorpion bite simulate the neurotoxic snakes (cobra and krait)
  • The toxicity of scorpion venom is more than that of snakes, but only quantity is injected.
  • The mortality, except in children, is negligible

Exam Important

  • Rati: Raw  or cooked  seeds,  when  swallowed  are  non-poisonous.  But  if  extract  is  injected  into  wound or under  skin, poisonous  symptoms  occur  which resemble  viper  bite.
  • used to  produce artificial  bruises.
  • It is  also  used  by  washerman  to  mark clothes.
  • Fatal dose of croton is  4-5 seeds or 1-2 ml (20  drops of  oil).
  • Cantharides  produces  a  poison  called  contharidin.
Don’t Forget to Solve all the previous Year Question asked on Vegetables, Cantharides and Scorpion Poisons

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Corrosives Poisoning: Magenstrasse

Corrosives Poisoning: Magenstrasse


Introduction

  • corrosives  Poisoning: Magenstrasse(the gastric cannal or furrow)
  • It is a groove in the stomach along the lesser curvature that is the route food and liquids tend to take in moving toward the pylorus and that is a frequent site of peptic ulcer formation.

Corrosives  fix,  destroy  and erode  the  surface  with which  they  come  in  contact.  They mainly  act locally  by 

  1. Hygroscopic: Extraction  of  water from  tissues,
  2. Coagulation  of proteins  and
  3. Conversion  of haemoglobin  into  hematin.

As  a  rule  there  is  no  remote  systemic  action  with  exception to  shock.  Corrosives  are:

  1. Mineral  acid:  Sulphuric  acid (H2SO4),  nitric acid, hydrochloric acid.
  2. Organic  acid: Oxalic  acid,  carbolic  acid,  salicylic acid,  acetic  acid.
  3. Vegetable  acid:  Hydrocyanic  acid.
  4. Alkalis:  Caustic  potash,  caustic  soda,  ammonium  hydroxide.
  • Magenstrasse  is  the  term  applied  to  the  pathway  acidic  agents  follow  in  stomach.
  • The  pathway  of  acids and alkalis  in  food  filled  stomach  starts  along  the  lesser  curvature  of  the  stomach  and leads  to  the  pylorus.
  • This  explains  the location  of greatest damage in  food  filled  stomach.
  • Stomach  without  food  have significant  injury  in  the  lower  half  of  two thirds and  may  have sparing  of fundus.

Exam Important

  • Magenstrasse  is  the  term  applied  to  the  pathway  acidic  agents  follow  in  stomach.
  • The  pathway  of  acids and alkalis  in  food  filled  stomach  starts  along  the  lesser  curvature  of  the  stomach  and leads  to  the  pylorus.
  • This  explains  the location  of greatest damage in  food  filled  stomach.
  • Stomach  without  food  have significant  injury  in  the  lower  half  of  two thirds and  may  have sparing  of fundus.
Don’t Forget to Solve all the previous Year Question asked on Corrosives Poisoning: Magenstrasse

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Laws of poisoning

Laws of poisoning


The  laws  related  to  poisoning  are  :

(A) The drugs  and  cosmetic  act  1940:

  • The main aim  is  to  control  quality,  purity  and strength  of drugs. 
  • The act  has  been further  amended  by  drugs (Amendment) act  1964to  include  ayurvedic  and  unani  drugs.
  • The  label  or container of medicine  should  display  the  formula  or a list  of ingredients  contained  in  the  drug.

(B) The drug  and  cosmetic  rules  1945  :

  • It was formed  to  regulated  drugs,  the  functions  and procedures  of central drug  laboratory,  appointment  of licensing  authorities  and  manufacture, distribution  and  sale  of drugs.
  • These  rules  have classified  drugs  into  schedules  as follows:

Schedule

Drugs

Schedule C

Biological and special products

Schedule E

Poisons

Schedule F

Vaccine and sera

Schedule G

Hormone preparations, Anti histamines, Anti-cancer

Schedule H

Drugs and poisons to be sold only by prescription of a Registered medical practitioner

Schedule J

List of diseases for the cure and prevention of which, no drug should be advertised (cataract,

epilepsy, hydrocele, blindness etc)

Schedule I

Antibiotics and other recent chemotherapeutic agents

(C) Narcotic drugs  and psychotropic  substances  (NDPS)

  • It  was amended  in  1989  and 2001. It  repeals  three  acts (i)  The  opium  act  1857,  (ii)  The opium  act  1878, (iii) The dangerous drug  act  1930.
  • An amendment  has  diluted  and  made the  punishment  less  severarr2)  for  drug  offenders.
  • It  provides  identification,  treatment  and rehabilitation  of  drug addicts
  • Important  drugs/substances under  Narcotic  Drugs  and Psychotropic  Substances  (NDPS)  Act +  1985, Natcotics: Coca  leaf  (Cocaine), cannabis,  opium,  (including heroin), poppy  straw.

ii) Psychotropic  substances;  LSD, amphetamines, tranquilisers,  barbilurates,  benzodiazepines, methaqualone, psilocybine,  phencyclidine,  mescaline  etc.

Prevention  of  illicit  trffic  in  narcotic  drugs  and  psychotropic  substances  act  1988

Exam Important

  •  schedule H is for Drugs and poisons to be sold only by prescription of a Registered medical practitioner.
  • (NDPS) It  was amended  in  1989  and 2001. It  repeals  three  acts (i)  The  opium  act  1857,  (ii)  The opium  act  1878, (iii) The dangerous drug  act  1930.
  • An amendment  has  diluted  and  made the  punishment  less  severarr2)  for  drug  offenders.
  • It  provides  identification,  treatment  and rehabilitation  of  drug addicts
  • Important  drugs/substances under  Narcotic  Drugs  and Psychotropic  Substances  (NDPS)  Act +  1985, Natcotics: Coca  leaf  (Cocaine), cannabis,  opium,  (including heroin), poppy  straw.

 

Don’t Forget to Solve all the previous Year Question asked on Laws of poisoning

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Hair: Examination, Importance, & difference between Human Hair Vs. Animal Hair

Hair: Examination, Importance, & difference between Human Hair Vs. Animal Hair


Introduction:

Hair Examination Importance

  • Identification: Identification  of  individual  which may  be  accused, mutilated body etc.
  • Source:  Source of origin, whether  animal  or human.
  • Sexual  offences: Rape and  unnatural  sexual  offences.
  • Crimes: Hair or fibers  found  at  the  scene  on  weapons  or clothes  helps in identification  of  accused.
  • Hit and  run case: When  specimens  of hair removed  from  various  parts of the  motor car  are  sent by authorities  for comparison  with victim’s hair.
  • Chronic  poisoning  by metals: Arsenic, antimony  radium  and  thallium. 

Examination Of Hair can be done by:

  • Temporary Mount
  • Scale Casting    (i) Cellulose Acetate Method     (ii) Polaroid Coater Method
  • Permanent Mount Cross
  • Sectioning Micrometry.

ldentification  of race  by hair

Human  hair Vs Animal hair

Exam Important

*4-+

Hair Examination Importance

  • Identification: Identification  of  individual  which may  be  accused, mutilated body etc.
  • Source:  Source of origin, whether  animal  or human.
  • Sexual  offences: Rape and  unnatural  sexual  offences.
  • Crimes: Hair or fibers  found  at  the  scene  on  weapons  or clothes  helps in identification  of  accused.
  • Hit and  run case: When  specimens  of hair removed  from  various  parts of the  motor car  are  sent by authorities  for comparison  with victim’s hair.
  • Chronic  poisoning  by metals: Arsenic, antimony  radium  and  thallium.
Don’t Forget to Solve all the previous Year Question asked on Hair: Examination, Importance, & difference between Human Hair Vs. Animal Hair

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Seminal stains.

Seminal stains.


Introduction.

  • Sensabaugh in 1977 reported the event of isolation of p30 in human seminal  fluid.  It is a glycoprotein of prostate origin.
  • Detection  of seminal  stains  becomes  important  in cases  of  rape, attempted  rape, sexual  murders of  female, kidnapping, sodomy, bestiality, adultery  and  indecent  assault  etc.
  • Seminal  stains  are  generally found  on  the  clothing, but  may be present  on  the  body  of  the  victim  or  accused,  on  the  bed  clothes,  site of offence,  seat  of motor car; on the  floor  or on  the grass.
  • Normal semen reference pH range is 7.2 to 7.8. Variations in volume and low pH may be  due to congenital abnormalities of the genital tract or to obstruction.

Tests  to  detect  semen are  :

A) Chemical  tests  :These tests  are  divided  into  :

1) Microchemical  tests  :

Florence  test:

  1. This test was discovered by Dr.Florence in the year 1886.
  2. When Florence reagent (PotassiumIodide+Iodine+Water) is applied to the slide it produces rhomboidal shape  dark crystals of choline periodide.
  3. choline can be detected if swab is collected within one day of sexual act,

Barberio’s  test:

  1. Invented by Barberio in the year 1905.
  2.  When the questioned stain is  allowed to react with picric acid it leads to the formation of yellow needle shaped  spermine picrate crystals.

2) Enzyme tests: Since spermatozoa contain gram positive protein, the  presence of spermatozoa will be confirmed by microscopic appearance of purple bodies

Acid phosphatase & specific glycoproteins:

  1. This test is adopted because of high acid  phosphatase activity of semen.
  2. Stability of  acid phosphatase activity in seminal stain depends on temperature

3) Ammonium  molybdate  test:  lt  gives  deep  yellow  colour, due to  presence  of phosphorus. 

B)  Microscopic examination : It  is  done  to  demonstrate the  presence of  spermatozoa in  the  vaginal fluid  or in  stain. 

C)  Biological  examination:

  • Precipitin  test  :  To  know  the  species  to  which  semen  belongs.
  • Blood  group  can  be  known  from  semen

D)  UV light:

  • Invisible,  softened  and dry  semen  stains of the  clothes can  be  rendered  distinct  by  the  filtered UV light which  produces  bluish  fluorescence.
  • A mercury lamp inside of the unit produces a high intensity of UV (320-400nm) and visible light (400-700 nm) which was developed  to detect biological stains even in daylight.

E) Testes  for  determination  of  specific protein  component (e.g. LDH  isoenzyme):

  • These are  immunoelectrophoresis,  gel  diffusion  precipitation, gel  electrophoresis,  immunodiffusion,  isoelectric focusing  and TLC (thin  layer  chromatography).

Exam Important

A) Chemical  tests  :These tests  are  divided  into  :

1) Microchemical  tests  :

Florence  test:

  1. This test was discovered by Dr.Florence in the year 1886.
  2. When Florence reagent (PotassiumIodide+Iodine+Water) is applied to the slide it produces rhomboidal shape  dark crystals of choline periodide.
  3. choline can be detected if swab is collected within one day of sexual act,

Barberio’s  test:

  1. Invented by Barberio in the year 1905.
  2.  When the questioned stain is  allowed to react with picric acid it leads to the formation of yellow needle shaped  spermine picrate crystals.

2) Enzyme tests: Since spermatozoa contain gram positive protein, the  presence of spermatozoa will be confirmed by microscopic appearance of purple bodies

Acid phosphatase & specific glycoproteins:

  1. This test is adopted because of high acid  phosphatase activity of semen.
  2. Stability of  acid phosphatase activity in seminal stain depends on temperature

3) Ammonium  molybdate  test:  lt  gives  deep  yellow  colour, due to  presence  of phosphorus. 

B)  Microscopic examination : It  is  done  to  demonstrate the  presence of  spermatozoa in  the  vaginal fluid  or in  stain. 

C)  Biological  examination:

  • Precipitin  test  :  To  know  the  species  to  which  semen  belongs.
  • Blood  group  can  be  known  from  semen

D)  UV light:

  • Invisible,  softened  and dry  semen  stains of the  clothes can  be  rendered  distinct  by  the  filtered UV light which  produces  bluish  fluorescence.

 

Don’t Forget to Solve all the previous Year Question asked on Seminal stains.

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Thermal injuries: chemical, electric and Lightening burns.

Thermal injuries: chemical, electric and Lightening burns.


Introduction:

Chemical burns:-

  • Chemical burns are produced by corrosive acids and alkalis.
  • Acids with a pH less than 2 precipitate proteins causing coagulation necrosis.
  • Nitric acid gives a yellow-brown scab, sulphuric (vitriol) a black-brown scab,
  • Hydrochloric acid (spirit of salt) a white to grey scab, and carbolic acid (phenol or Lysol) gives a light grey to light brown scab.
  • Alkalis with a pH above 11.5 cause more tissue damage than acids because they induce liquefactive necrosis, which facilitates ever deeper penetration of the alkali.
  • The caustic alkalis, such as sodium hydroxide (caustic soda or lye) and ammonium hydroxide, leave a grey-white mucoid burn.
  • Vesicles  and blisters, Charring  (soot)  and  singeing  are absent, except  in  cases  of mineral  acids  where  they  are present.
  • The most serious alkali burns of the eye are produced by: Strong liquid ammonia.

Electric burns:-

  • High tension electrical burns from overhead electric lines can cause Myoglobinuria and Acute renal failure.
  • Electric  burns  are  at  times,  also  referred  to  as joule  burns.
  • Regarding high-voltage electrical burns to an extremity.  Evaluation for fracture of the other extremities and visceral injury is indicated.
  • Ulceration  is  present, Coagulative necrosis  is  seen  at the  site of contact  except  for  hydrogen  fluoride  which chelate  calcium.
  • Calcium  phosphate  of bones  may also  melt and  is  radiologically  seen  as  bone pearls  (wax  dripping), Muscles  show  Zenker’s  degeneration.
  • commonest  cause  of  death in electric injury  is  ventricular  fibrillation.
  • The skin may get coloured due to metallic pigment :- green (in brass electrode), black (in iron electrode), blue (in copper electrode) and grey (in aluminium electrode).
  • In high-voltage (more than 1,000 volts) electrical burns the contact injury of exit often appears as a blow-out type of wound.
  • Alternating current (AC) is more dangerous than direct current (DC).

Lightening  burns

  • Lightening refers  to  discharge  of current  between  a negatively charged  cloud and  positively  charged  article  on  earth.
  • Direct  effect  of high voltage  current.
  • Heat,  i.e.  super  heated  air causing  burns.
  • Expanded  and displaced  air, which acts as  a  blast wave
  • Sledge  hammer  blow  by compressed  air pushed before.
  • The  characteristic  finding  in  lightening  burns is  filigree  burns.

Exam Important

  • Chemical burns are produced by corrosive acids and alkalis.
  • Acids with a pH less than 2 precipitate proteins causing coagulation necrosis.
  • Nitric acid gives a yellow-brown scab, sulphuric (vitriol) a black-brown scab,
  • Hydrochloric acid (spirit of salt) a white to grey scab, and carbolic acid (phenol or Lysol) gives a light grey to light brown scab.
  • Alkalis with a pH above 11.5 cause more tissue damage than acids because they induce liquefactive necrosis, which facilitates ever deeper penetration of the alkali.
  • The caustic alkalis, such as sodium hydroxide (caustic soda or lye) and ammonium hydroxide, leave a grey-white mucoid burn.
  • Vesicles  and blisters, Charring  (soot)  and  singeing  are absent, except  in  cases  of mineral  acids  where  they  are present.
  • The most serious alkali burns of the eye are produced by: Strong liquid ammonia.
  • High tension electrical burns from overhead electric lines can cause Myoglobinuria and Acute renal failure.
  • Electric  burns  are  at  times,  also  referred  to  as joule  burns.
  • Regarding high-voltage electrical burns to an extremity.  Evaluation for fracture of the other extremities and visceral injury is indicated.
  • Ulceration  is  present, Coagulative necrosis  is  seen  at the  site of contact  except  for  hydrogen  fluoride  which chelate  calcium.
  • Calcium  phosphate  of bones  may also  melt and  is  radiologically  seen  as  bone pearls  (wax  dripping), Muscles  show  Zenker’s  degeneration.
  • commonest  cause  of  death in electric injury  is  ventricular  fibrillation.
  • The skin may get coloured due to metallic pigment :- green (in brass electrode), black (in iron electrode), blue (in copper electrode) and grey (in aluminium electrode).
  • In high-voltage (more than 1,000 volts) electrical burns the contact injury of exit often appears as a blow-out type of wound.
  • Alternating current (AC) is more dangerous than direct current (DC)
Don’t Forget to Solve all the previous Year Question asked on Thermal injuries: chemical, electric and Lightening burns.

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Hanging: Postmortem findings,Strangulation,Medico-legal aspects of hanging.

Hanging: Postmortem findings,Strangulation,Medico-legal aspects of hanging.


Introduction

Postmortem findings

  • Ligature  mark is  above  thyroid  cartilage,  inconplete,  bitaterally  symmetrial  and  directed  obliquely  upward extending  to  the  angles  of  mandible,  then  to  mastoid  and  finally  to  occipital protuberance.  Ligature  mark is  an example  of  imprinted/pressure/patterned  abrasion.
  • There is  dribbling of saliva  from  the  angle  of the  mouth  which  is  confirmatory sign  of antemortem
  • Hanging. This is  due to  irritation  of submandibular  and parotid  glands  by  ligature.
  • There  may  be intimal  tear  of carotid  arteries.
  • In  case  of pressure  of ligature  on cervical  sympathetic  ganglia,  the  eye on that  side is  found  open  (La  facie sympathique) .
  • Fracture  of hyoid  is  usually  not seen (may be  seen  only in  l0%). Fracture of thyroid  cartilage
  • (20-30 %  cases)  and fracture  of tracheal  rings  (5-l0 %)  may  be  seen.
  • There  may  be  congestion  and ecchymosis (hemorrhage)  in trachea’ larynx, epiglottis  and esophagus. 
  • All these  injuries  are more  common  in  strangulation  because  strangulation is  more violent  than  hanging causing  more severe  injury  to  neck structures.
  • Tardieu spots (petechial  hemorrhage) are  not as  Pronounced  as  in  strangulation.

STRANGULATION

  • Strangulation  is  the  form  of asphlxia  caused by  constriction  of  neck  by ligature  or some  other method,  but  without suspension  of  the  body.  So the  force  constricting the  neck is  external  force  (not  the  weight  of  the  body as  occurs  in hanging).

Depending upon  the  method  used  to  constrict  the  neck,  strangulation  can  be  divided  into:

  1. Ligature strangulation  :  Neck  is  compressed by  a  ligature  of  which  usually  multiple rounds  are  given  and  no  knot is  tied.
  2. Throttling  (manual  strangulation)  : Neck  is  compressed  by  one or both  hands. When neck  is  compressed by  two  palms,  it  is  known  as  palmar  strangulation.
  3. Bansdola: Compression  of neck with  one or two  wooden sticlcs  or  bamboo.
  4. Garrotting: It  is  compression  of  neck  by  a rope  thrown  from  behind.  Spanish windlass  is a type  of  garrotting,  which used  to  be  the  official  mode  of  execution  in  spain.  In  this,  an  iron  collor  around  the  neck was tightened  by a  screw for  strangulation.
  5. Mugging  (choke  hold) :  It  is  compression  of neck by  forearm  or in  the  bend  of elbow.
  6. Strangulation  by  knee/foot :  In  this,  neck  is  compressed by  knee  or foot.

Medico-legal aspects of hanging:

  • Hanging is invariably suicidal, until unless otherwise proved. In a suicidal hanging, any  material available at that moment of time can be used for the act. A foot stool may be  found at the scene of the death  which is used for reaching the point of suspension.
  • Tragic cases of accidental hanging are also reported where children play dangerous  games including simulation of hanging.
  • Lynching is a form of homicidal hanging  where an accused  of murder  or rape is hanged in a public square by a mob as a part of carrying out justice.
  • Judicial hanging:  In some countries, including India, hanging is the mode of carrying  out  capital punishment or legal execution of death sentence. The rope is allowed to drop 5 to 7 metres  according to the height and weight of the person. Bilateral fracture of the pedicle of the  second-third or third-fourth cervical  vertebrae occurs which is called hangman’s fracture.
  • Sudden stop causes fracture dislocation usually at level of C2-C3 or C3-C4 vertebra, and injury to spinal cord and brainstem (pons and medulla).
  • the dislocation of the atlanto occipital joint or the odontoid process of  the axis vertebra causes pulping of the spinal cord and transaction of the cervical cord. There even can be rupture of the brain stem with proper judicial hanging.
  • Postmortem hanging:  Sometimes the victim may be murdered by some other means  and then hanged postmortem in order to mislead the police. thorough and meticulous postmortem examination, the original cause of death can also be established.

Exam Important

  • Hanging. This is  due to  irritation  of submandibular  and parotid  glands  by  ligature.
  • There  may  be intimal  tear  of carotid  arteries.
  • In  case  of pressure  of ligature  on cervical  sympathetic  ganglia,  the  eye on that  side is  found  open  (La  facie sympathique) .
  • Fracture  of hyoid  is  usually  not seen (may be  seen  only in  l0%). Fracture of thyroid  cartilage
  • (20-30 %  cases)  and fracture  of tracheal  rings  (5-l0 %)  may  be  seen
  • Lynching is a form of homicidal hanging  where an accused  of murder  or rape is hanged in a public square by a mob as a part of carrying out justice.
  • Judicial hanging:  In some countries, including India, hanging is the mode of carrying  out  capital punishment or legal execution of death sentence. The rope is allowed to drop 5 to 7 metres  according to the height and weight of the person. Bilateral fracture of the pedicle of the  second-third or third-fourth cervical  vertebrae occurs which is called hangman’s fracture.
  • Sudden stop causes fracture dislocation usually at level of C2-C3 or C3-C4 vertebra, and injury to spinal cord and brainstem (pons and medulla).
  • the dislocation of the atlanto occipital joint or the odontoid process of  the axis vertebra causes pulping of the spinal cord and transaction of the cervical cord. There even can be rupture of the brain stem with proper judicial hanging.
  • Postmortem hanging:  Sometimes the victim may be murdered by some other means  and then hanged postmortem in order to mislead the police. thorough and meticulous postmortem examination, the original cause of death can also be established.
Don’t Forget to Solve all the previous Year Question asked on Hanging: Postmortem findings,Strangulation,Medico-legal aspects of hanging.

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