Identify ancient Egyptian mummies

May 6, 2011

Identify ancient Egyptian mummies

In the 1980s, the Manchester Mummy Project pioneered the use of endoscopy as a virtually nondestructive method of obtaining samples for paleohistology (the study of tissue in ancient remains), immunological techniques, and DNA
identification. Endoscopy originated for medical purposes: An endoscope is a narrow tube with an electric light on the probing end that can be inserted into one of the natural orifices of the body or a small incision made in the chest or the abdominal wall. Endoscopy enables doctors to see structures inside the body and to remove samples for examination under a microscope.


By the 1980s, endoscopes had been greatly improved and included fiberscopes, which incorporated a bundle of tiny transparent fibers that transported light in both directions and allowed light to follow a curved path without distorting the image. By this time, special rigid endoscopes had also been developed for industrial purposes, and since the tissue of mummies is hard and unyielding, these have proved most successful in Egyptological studies.

By attaching a small retrieval forceps to the probing end of the endoscope, the Manchester team produced an instrument that could be used to take biopsy samples from inside the mummy.
The existing bodily orifices or small holes caused by later damage were used as a means of entry into the mummy. The position of the probing end of the instrument within the body could then be directly visualized on a radiographic screen or monitor, and the retrieval forceps manipulated from outside the mummy permitted researchers to take the required biopsy samples.

PALEOPATHOLOGY

At the beginning of the twentieth century, M. A. Ruffer (1859–1917), professor of bacteriology at the Cairo School of Medicine, laid the foundations for the study of disease in ancient populations, for which he coined the term paleopathology. This field includes anthropology, archaeology, paleontology, and paleohistology and attempts to trace the appearance, development, and disappearance of diseases, as well as demonstrating the effect of some diseases on given ancient societies.

Today, pathology, or the scientific study of disease processes, includes two branches—morbid anatomy and histopathology—which have both provided much information about diseases in mummies. Morbid anatomy relies on the naked-eye study of the body. Histopathology, which demonstrates changes in tissue caused by disease, can draw upon a range of techniques to detect disease in tissue samples, including histology, which focuses on the microscopic structure of the tissues; electron microscopy, which enables histologists to examine tissue at magnifications greater than 800 times normal size; and immunohistochemistry, which improves the histologist’s opportunity to identify cell constituents in the mummified tissue through specialized stains.

Paleohistology, pioneered by Daniel Marie Fouquet (1850–1914) in 1889, was subsequently implemented by Ruffer to examine the state of preservation of the structures in ancient tissue and to detect the presence of disease. Ruffer, in turn, pioneered the basic technique of rehydrating (softening) and fixing the tissue, which could then be processed in the same way as modern samples, which are either frozen or surrounded by paraffin wax and cut into thin sections. Next, these sections are stained selectively with different dyes, which have a special ability to highlight particular parts of the tissue or cells.
The individual sections are then examined under a light microscope. Continuing research has refined and improved rehydration and staining techniques, and their use has identified many examples of disease in mummies.
Findings often include diseases caused by parasitic infestations where the remains of the worms or the eggs can be identified microscopically. Examples that have been discovered include a round worm (Ascaris), a cyst originating from a Trichinella infestation, the eggs of the Tae-nia tapeworm, Filaria worms, and the eggs and worms that cause schistosomiasis (Bilharzia).
In most mummies thus examined, there is evidence of multiple infestation by different parasites.
Further information has been obtained by using electron microscopy, which provides much better resolution of the detailed structures within a tissue sample. Transmission electron microscopy (TEM), analytical electron microscopy (AEM), and scanning electron microscopy (SEM) have all been used to examine mummies and have made it possible to identify the remains of particular parasites.
Also, using AEM, researchers have been able to go so far as to demonstrate that dense crystalline particles found in a sample of lung tissue are silica particles, indicating that the owner had suffered from the disease known as Sand pneumoconiosis. This is a common problem in parts of the world where the population is exposed to sandstorms.
As well as detecting disease in mummies, these techniques have a wider range of applications. Some research has been carried out to analyze the chemical constituents of mummified tissue, and studies have also been under-taken on particular areas such as the skin or eyes.
TEM was used to investigate the ultra-structure of ancient skin and muscle tissue, for example, and SEM has been employed to examine hair and to identify insects found inside the mummies. Also, scientists have used AEM to examine mummified tissue in an attempt to detect the presence of metals, such as lead, that accumulate in small quantities in the body. Immunohistochemistry has further added a new dimension to these studies.

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