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Forensic Dermatopathology

by: Harina Vin

Forensic science, as defined by Wikipedia, is “the application of a broad spectrum of sciences to answer questions of interest to a legal system.” One such science, currently undeveloped for use in forensics, is dermatology and dermatopathology. Examination of the skin is a critical part of the forensic examination, as the skin has the potential to reveal signs of internal disease or external trauma, an approximate time of death or injury, or clues to the identity of an individual.

Detection of Drug and Chemical Use

The simplest way to detect drug and chemical use of an individual in forensic cases is to analyze hair and nail samples. This method is particularly useful because it is easily and non-invasively collected.3 Biological substances accumulate in hair and nail, where they can be measured even in small sample sizes. The hair and nails may also give a history of drug intake and abuse, as well as toxin exposure. The nail on the large toe reflect body exposure to toxins up to 12 months previous.3 In the same way, long scalp hair may provide retrospective information of the previous 5 to 7 years. In fact, the basic chemical composition of the hair shaft and nail plate is not influenced by changes in the blood chemistry or by exposure to chemicals which occurred after hair and nail formation.9, 10

Transverse leukonychia, also known as Mee’s lines, are nail abnormalites caused by toxins like arsenic and thallium.13, 16 Fingernail clippings of victims have been utilized in looking for the DNA of aggressors in cases where the victims struggled to defend themselves.8 The identification, however, may be difficult due to the fact that the aggressor’s DNA is often too low in quantity to be detected. Certain hair loss patters are indicative of some poisoning which may lead to the diagnosis.5

In a case study, a 16-year-old girl was admitted to a hospital for weakness and weight, and was found to have white, transverse, and nonpalpable lines on each of her nails. Dermatology was consulted regarding the patient’s abnormal nails, consistent with Mee’s lines. The patient’s hair and nails were analyzed and arsenic was found, initiating a criminal investigation. The investigation uncovered the following:

“Upon taking further history, her father had died recently. His body was exhumed and arsenic was found. It was then discovered that the previous husband of the child’s mother had died in middle age. His body was exhumed and arsenic was again found. About that time, the mother disappeared. She was found several years later and charged and convicted of murder and attempted murder.”3 In this case, dermatologic symptoms allowed the discovery of a legal incident using hair and nails.

Detection of Abuse

In living patients, certain chronic and recurring dermatologic symptoms can occur in patients following psychologic trauma events. Examples are cutaneous sensory flashbacks, autonomic hyperarousal (with symptoms such as profuse sweating or flare-up of an underlying stress-reactive dermatosis), conversion symptoms (such as numbness, pain, or other medically unexplained cutaneous symptoms), and cutaneous self-injury (manifesting in many forms, including trichotillomania, dermatitis artefacta, and neurotic excoriations— tension-reducing behaviors in patients who have posttraumatic stress disorder).4 These dermatologic symptoms can be indicative of psychological abuse and pursued by forensic scientist.urn victims also exhibit certain skin characteristics. In electrical lesions, cell cytoplasm appears homogeneous often with a peculiar white color in hematoxylin-eosin stained sections, and overall morphology of the cells are affected, likely because of pH shifts in the cells.15

Interestingly, forensic dermatology can also be used to rule out abuse. A case study was conducted of an 82-year-old man in a nursing home receiving treatment for colon cancer. One night, he unexpectedly dies. His right cheek is described as “red with blisters” and his family is concerned that he had experienced a burn to his face due to neglect or abuse from the nursing home staff. An autopsy is performed which confirms a diagnosis of metastatic adenocarcinoma of the colon. Skin biopsies are also performed, and cells of the epidermis stain positively for antivaricella zoster antibody. Afterward, the viral tissue culture grows varicella zoster virus. The findings established “herpes zoster as the cause of the man’s right cheek erythematous-based blisters and excluded the possibility of a burn, neglect, or abuse by the nursing home staff.”2

Time of Death

Attempts to estimate age of skin bruises is of considerable importance in forensic pathology. One way age is estimated is using time-dependent changes of color. For example, a bruise older than 18 hours is predicted to appear yellow in light-microscope histology. 6 Apoptosis activity found in the post-mortem skin is most probably reliable way of determining age of an injury.12 In general, the apoptotic process is associated with condensation of cytoplasm followed by phagocytosis and digestion by surrounding cells, the steady state mass of a tissue being related to the balance between cell formation (mitosis) and cell destruction (via apoptosis).7 Thus, the relationship betweenapoptosis and physical injury in skin, can aid forensic dermatologist in identifying time of death. mass of a tissue being related to the balance between cell formation (mitosis) and cell destruction (via apoptosis).7 Thus, the relationship betweenapoptosis and physical injury in skin, can aid forensic dermatologist in identifying time of death.

Victim Identification

Some obvious method for identification of unknown human bodies are visual identification, fingerprints, and DNA fingerprinting.17 One more important and less spoken forensic tool to establish identity in an unknown deceased is occupational skin lesions, that is, lesions acquired in the course of a person’s daily profession. Different occupations produce characteristic effect on different parts of body due to use of tools or machines or exposure to different chemicals in the working environment. Examples of profession-specific dermatologic indicators include “ rough hands seen in manual labourer involved in construction work, excavated chest in a cobbler, callosities of finger tips in a stenographer, callosities of palm at the base of fingers in butchers, burn scars over the back of both hands seen in blacksmiths, involuntary permanent tattooing of micro particles of coal found on the hands of the labourers involved in mining industry.”11

A rare case was reported, where the identity of an unknown elderly male who committed suicide by hanging was established based on the symmetrical distribution and pattern of skin lesions acquired during the course of his occupation. As a coconut tree climber, he gripped the coconut tree with both hands and feet, and then pushed up the body to climb higher. This resulted in intermittent pressure over the forearm skin, palms, and soles in response to friction, causing deposition of thickened, vertically oriented collagen bundles in papillary dermis, resulting in lichenification.1 The family of the individual later confirmed his identity.

The Future

Within the next decade, it is likely that the implementation of currently available and new techniques for the diagnosis and relevance of skin and mucosal conditions will continue to provide significant scientific advances in this promising area of forensics.2 These fields are awaiting further definition, categorization, and investigation.


1. Adams R.M. Occupational skin disease. In: I.M. Freedberg, A.Z. Eisen, K. Wolff, K.F. Austen, L.A. Goldsmith, S.I. Katz and al. et, Editors, Fitzpatrick’s Dermatology in General Medicine, McGraw-Hill, New York (1999), pp. 1609–1620.
2. Cohen P.R. Forensic Examiner [Online] Fall 2009.
3. Daniel C.R.; Piraccini B.M.; Tosti A. Journal of the American Academy of Dermatology. [Online] 2004, 50.2, 258-261.
4. Gupta M.A.; Lanius R.A.; Van der Kolk B.A. Dermatologic Clinics. [Online] 2005, 23.4, 649-656.
5. Hubler W.R. South Med J. [Online] 1966, 59, 436–442.
6. Langlois N.E. and Gresham G.A. Forensic Sci. Int. [Online] 1991, 50, 227–238.
7. Olson P.L. and Everell M.A. J. Cutaneous Path. [Online] 1975, 2, 53–57.
8. Oz C. and Zamir A. J Forensic Sci. [Online] 2000, 45, 158–160. Palmeri A; Pichini S; Pacifici R; Zuccaro P; Lopez A. Clin Pharmacokinet. [Online] 2000, 38, 95-110.
9. Pichini S; Altieri I; Zuccaro P; Pacifici R. Clin Pharmacokinet. [Online] 1996, 30, 222-228.
10. Polson C.J.Identification. In: C.J. Polson and Gee DJ, Editors, The Essentials of Forensic Medicine, Pergamon press, Oxford (1973), pp. 85–87.
11. Sawaguchi T; Jasani B; Kobayashi M; Knight B. Forensic Science International. [Online] 2000, 108.3, 187-203.
12. Seavolt M.B.; R.A. Sano; K. Levin; C. Camisa, Int J Dermatol. [Online] 2002, 41, 399–401.
13. Shetty B.S.; Rao, J; Samer K.S.; Salian P.R., Shetty M. Forensic Science International. [Online] 2009, 183.1, 17-20.
14. Thomsen H.K.; Nielsen D.O.; Aalund O.; Nielsen K.G.; Karlsmark T. Genefke I.K. Forensic Science International [Online] 1981, 17.2, 145-152.
15. Tromme I.; Van Neste D.; Dobbelaere F.; Bouffioux B.; Courtin C.; Dugernier T. Br J Dermatol [Online] 1998, 138, 321–325.
16. Weedn V.W. Clin. Lab. Med. [Online] 1998, 18, 115–137.

The Black Hole War

by: Phillip Choi

Most people don’t know or even care too much about black holes. The basic premise of a black hole is easy to grasp: A black hole is an incredibly compact mass that has so much gravity that nothing, even light, can escape from it. However, what happens to something when it does get sucked into a black hole? The answer to this seemingly innocuous question was debated by Leonard Susskind and Stephen Hawking for more than two decades. Leonard Susskind’s account of his twenty three year battle with Stephen Hawking over the fundamental nature of black holes is brilliantly recounted in his “Black Hole War”.

Most people don’t know or even care too much about black holes. The basic premise of a black hole is easy to grasp: A black hole is an incredibly compact mass that has so much gravity that nothing, even light, can escape from it. However, what happens to something when it does get sucked into a black hole? The answer to this seemingly innocuous question was debated by Leonard Susskind and Stephen Hawking for more than two decades. Leonard Susskind’s account of his twenty three year battle with Stephen Hawking over the fundamental nature of black holes is brilliantly recounted in his The Black Hole War.

The Black Hole War started in 1981 during an informal meeting of eminent physicists in San Francisco at the mansion of a rich New Age self help guru. During his presentation, Stephen Hawking proposed that information that falls into a black hole is eventually lost permanently in black hole evaporation. If information really was lost forever within black holes, one of the key principles holding quantum mechanics together, information conservation, would be violated. Information conservation is a simple law that states information cannot be lost or gained in the universe. That day, only Susskind and Gerard ‘t Hooft, a preeminent Dutch physicist, were troubled by Hawking’s conclusion. Despite all the mental acrobatics normally required for theoretical physics, Susskind and ‘t Hooft felt there was something intuitively wrong with losing information within a black hole because losing information is the same as increasing entropy. This entropy would become heat, which meant, “if Stephen was right, empty space would heat up to a thousand billion billion billion degrees in a tiny fraction of a second.” This bit of reasoning was the beginning of twenty three years of work to conclusively prove Hawking wrong.

Susskind recognizes that as a theoretical physicist writing for a lay audience, he must provide a significant amount of background knowledge to make the Black Hole War somewhat intelligible. He starts at the most basic level possible by talking about the scale of numbers that the reader will be exposed to in the book. Then, Susskind deftly explains numerous concepts important to gravity, thermodynamics, relativity, and quantum mechanics, such as tidal forces, the Uncertainty Principle, the Equivalence Principle, time dilation, entropy etc. The presence of many illustrations and the absence of unnecessary equations are greatly appreciated.

The term “black hole” only came into the physics lexicon during the mid 1960s; the term is widely credited to John Wheeler. Before then, black holes were called gravitationally completely collapsed stars. The existence of black holes was first postulated by John Mitchell and Pierre-Simon Laplace in the late 18th century. However, it was not until the latter half of the 20th century that black holes were became more than extremely dense dead stars. It was agreed upon that there were only two key components when describing a black hole: the singularity and the horizon. The singularity is the center of the black hole where the mass of infinitely high density resides. The horizon is the invisible spherical boundary between the black star and the rest of the universe; once an object crosses the horizon, it will be pulled into the singularity and destroyed. Black holes were thought to be cold balls of mass that would be permanent fixtures in the cosmos. Now, it is recognized that black holes have can radiate heat, split into smaller black holes, evaporate into nothing and a whole bunch of other lively activities.

Susskind’s quest to prove Hawking wrong about the destruction of information in black holes results in two major theories: Black Hole Complementarity and the Holographic Principle. It should be noted that he worked with ‘t Hooft on the Holographic Principle. Both theories get around Hawking’s assertion by stating that even information that is sucked into a black hole is not actually “in” the black hole.

At the most basic level, Black Hole Complementarity states that what one observes while inside a black hole is different from what one observes outside the same black hole. For example, let’s say a person falls into a black hole while his friend watches in horror from a nearby spaceship. The friend outside the black hole in the spaceship will see his friend swallowed up and disintegrated as he passes the horizon. However, the person falling into the black hole will experience something entirely different: He will cross the horizon of the black hole without noticing any changes and continues living. He won’t feel his body being torn to bits by the black hole. (That happens when he reaches the singularity.) There seems to be a paradox here as two different events take place at the same moment. However, this paradox can be reconciled by the fact that, even theoretically, there is no way to experimentally prove there is a paradox because it would be impossible for the two observers to ever come together and compare their observations about crossing the horizon. Black Hole Complementarity is analogous to the wave-particle duality of light. In the same way that light is a particle and light is a wave, the observer crossing the horizon is destroyed and he is not. Black Hole Complementarity circumvents Hawking’s claim because even though we on the outside might see the bit of information being sucked into the black hole and evaporating as Hawking radiation, that bit of information actually still exists in the black hole.

The Holographic Principle is the second major development that came from Susskind’s war with Hawking. A hologram is a three dimensional image created by focusing light projected from a two-dimensional film surrounding the image. Susskind and ‘t Hooft’s Holographic Principle states that “everything inside a region of space can be described by bits of information restricted to the boundary.” This means that any object in the universe, even the largest ones like stars, galaxies, and the universe itself are simply holograms created from a massive, information-containing shell that surrounds the object. Whenever an object enters the boundary of one of these shells, the information regarding the object is encoded into the boundary and the boundary expands in proportion to the amount of information added. Incredible as it sounds, the Holographic Principle is now an accepted tool of theoretical physics. The Holographic principle solidly proves Hawking’s claim to be incorrect. If the holographic shell of a black hole is taken to be its boundary and the black hole itself is the object, any object or bit of information that enters the black hole will encode its information into the shell before entering the black hole. Thus, the information is conserved and not lost.

As Susskind and ‘t Hooft develop a the tools necessary to prove that black holes don’t swallow up and obliterate information, the nature of modern research becomes increasingly clear. Although Susskind and ‘t Hooft thought up the concepts of Black Hole Complementarity and the Holographic Principle, they must collaborate with many individuals to make the theories mathematically consistent with the physics establishment. Contributions from Cumrun Vafa, Ashoke Sen, Joseph Polchinski, Andrew, Strominger, Juan Maldacena, and Claudio Bunster were necessary to making Susskind and ‘t Hooft’s ideas sound. Brainstorming often took place at conferences where the various physicists would have relatively casual conversations about the problems they were having in their research. The general consensus regarding theories was taken via a straw poll at many of these conventions. Research didn’t take place in the offices of individual professors. Instead, it seems like a large family bickering and working together to find the “truth.”

Throughout the book, Susskind’s personality comes through loud and clear when he isn’t straightforwardly explaining the intricacies of his theories. It is very apparent that he is a grizzled physics professor willing to tell the war as he saw it without censoring himself. He recounts his encounters with other giants of theoretical physics, such as Richard Feynman, as a young student. When explaining the nature of black holes, he takes some time to discuss the reality behind some popular uses of black holes, such as time travel and teleportation. The consensus is that we can travel forward in time, but not backward, and worms holes, if they exist, could never actually be used to travel to an alternate universe or part of this universe. What’s most interesting is his characterization of Stephen Hawking. Very few people would have the audacity to call Hawking dense or get annoyed at how slowly it takes him to formulate answers using his synthesizer, but Susskind does. He’s willing to see the situation for what it is, not what it should be.

The Black Hole War is both highly informative and entertaining. Patience is required to understand the physics taking place, but it is rewarding to see how Susskind systematically attacks Hawking’s claim. I highly recommend The Black Hole War is you are looking to learn a little bit about how black holes work and how physicists wage war with each other.

Autism: Did the word make you think of mitochondria?

by: Christine Younan

For the past number of years, autism has been known to the general public as some vague disease of the brain, constituting various symptoms including abnormal social interaction, inappropriate communication, and the presence of stereotyped behaviors.1 This disease presents itself in a way that deems its origins worthy of some grand, subtle mismatched neural networks in the brain; however, it is only more recently that pediatric neurologists are looking beyond this seemingly too obvious origin of dysfunction to a more miniscule, mundane organelle: the mitochondrion. The mitochondrion provides a large alleyway for researchers of autism to begin their quest in seeking out the potential correlation autistic patients have with specific abnormalities in the mitochondria, an organelle present in numbers reaching the hundreds in nearly every cell of the body.

The mitochondrion: I remember that having some sort of significance in general biology. Let’s refresh. The mitochondrion is ultimately the cell’s powerhouse, producing vast quantities of adenosine triphosphate or ATP. In doing so, the mitochondria of the body break down carbohydrates and fats through a series of enzyme cascades and an electron transport chain. Because of the mitochondria’s significant presence in the body and the necessary metabolic processes it performs, the consequences of defects in this precious organelle already seem remotely dreary. When the mitochondria are deficient in their performance, “final end products from several metabolic systems may build up, causing in the metabolic systems themselves to shut down”.1 Additionally, the mitochondria play a role in signaling the cell to apoptose (analogous to suicide). When the mitochondria becomes defected, it can signal the cells to prematurely begin apoptosis, which leads to invariably unhealthy effects on the tissue in the vicinity, and ultimately on the organism as a whole.1 A defect in the mitochondrion can also “create reactive oxygen species that can be damaging to neighboring healthy tissues, as well as to individual cell function”.1 Ultimately, the effects appear quite challenging for cells with such idiosyncratic mitochondrion, but how do these effects interact to produce the symptoms of autism?

Because the mitochondria are primarily involved in production of cellular energy, the overall effect of the ill-suited mitochondria takes effect on the organs of the body that undergo ATP intensive processes. These processes include those of thinking, digesting, fighting off the latest strand of flu, and in short, many seemingly basic actions that require plethora of energy and complexity underlying their effectiveness. Therefore, a child with mitochondrial disorder may exhibit “developmental delay, loss of developmental milestones (i.e., regression), seizures, muscle weakness, gastrointestinal abnormalities, and immune dysfunction”.1 The overall presentation of these symptoms strongly resembles many of the multi-symptom effects of autism. Without even specific tests, the evident correlation of these two disorders makes it very probable that a child with autism may have mitochondrial disorder.

The actual diagnosis of mitochondrial disorder involves a series of blood tests and urine sampling that are often unrealized by the lack of information. However, one significant marker of mitochondrial disorder manifested in autistic children is the elevated levels of lactic acid. The mitochondrion cannot break down the pyruvate in the cell, and so the pyruvate then is left with no other choice than to decompose into lactic acid. A study on the relationship between elevated levels of lactic acid, as well as other traditional markers, associated to mitochondrial disease with autism were performed in Portugal; children believed to have autism underwent a muscle biopsy and nearly 7% were found to have confirmed mitochondrial disease.1 This remarkable study is one of the beginnings of an increasingly founded belief that a subset of autistic children may have mitochondrial dysfunction been overlooked.

Additionally, the connection of mitochondrial disease and autism can be vividly observed in the form of treatment applicable in both cases. Although medical treatments have truly improved, an exact remedy to mitochondrial disorder has not been prescribed. Certain vitamin supplements and diet adjustments, such as coenzyme Q10 (idebenone), are the essence of the treatment of this disease. The specific nuances in the prescription of treatments are “based upon rational biochemistry and knowledge of what vitamins/ cofactors may supplement the defective enzyme machinery or which diet may provide the best fuels for the specific disorder”.1 Such a treatment is analogous to the diet adjustments delineated for children diagnosed with autism.

Clearly, autism and mitochondrial disease contain a series of parallel symptoms, diagnoses, and treatments that maintain the idea that mitochondrial disease may be the precipitating factor of autism in many children. The mitochondria, with its vast sequence of enzyme cascades and energy formation and supply through ATP, provides a substantial means by which researchers of autism may begin to pin down specifics in what causes the symptoms of a disease which affects a significant proportion of young children today. Much work has yet to be done in this relatively novel field, but no doubt, an overwhelming amount of potential will be founded in the inner-workings of the mitochondria in curing autism.


1. Frye, R.; Poling, J. Mitochondrial Disorders and Autism. Biomedical, 2009.