“Elementary, My Dear Watson!” Clues Revealed About an Ancient Case of Leprosy

Unidentified remains found in the English countryside and all signs point to the untimely death of a young man. Researchers examined the bones of a supposed victim, which showed signs of leprosy, to search for clues about the arrival of … Continue reading »

The post “Elementary, My Dear Watson!” Clues Revealed About an Ancient Case of Leprosy appeared first on EveryONE.

A Disease of Considerable Antiquity: Cancer Detected in a Nubian Skeleton

Figure 11

Cancer, the transformation of normal cells into malignant tumor cells, reigns among diseases as one of the leading causes of death around the world. In 2012, cancer claimed 8.2 million lives, and numbers continue to increase each year. While our understanding of cancer is far from complete, we’ve been able to attribute some of the killer’s virulence to increased environmental risk: Increased pollutants and other environmental carcinogens, coupled with an average increase in tobacco and alcohol use and added to a concurrent decrease in daily exercise, cumulatively represent significant risk factors directly related to an increasingly modern world. Ironically, we humans also live a lot longer than we used to, which increases the disease’s chances of occurring.

However, we have identified far fewer examples of the disease in the archaeological record compared to its current frequency in the current population, which has led to the idea that cancer was much less widespread in antiquity. As a result, very little is known about its evolutionary history.

As part of a larger research project undertaken by the British Museum in the city of Amara West, Sudan, the authors of a PLOS ONE paper dug a little deeper into the dark, early history of cancer. Their subject of interest was an over 3,000 year-old skeleton of a young man from ancient Nubia, then part of Egypt, whose remains were excavated at this site, designated on the map below.

Figure 1

When the researchers uncovered skeleton 244-8, as he has been cataloged, they were presented with the difficulties of examining a less-than-complete body. Parts of the skeleton had been broken, highlighted as fragmentary in the image below. In addition, salt in the surrounding soil had slowly damaged the skull over time. The soft tissue of the over 3,000-year-old skeleton, was also long gone.

Figure 3

On top of these difficulties, damages to the body incurred over time, both before and after death, can look very similar to the eye. Cancer, in particular, is notoriously hard to diagnose in human remains; its similarities to other pathologies combined with natural damages sustained after burial made the researchers’ task of properly diagnosing skeleton 244-8 a complicated one. The earliest signs of cancer in bone are also only visible via methods like X-ray that allow us to visualize the inner parts of bone where the disease begins, which the naked eye cannot see.

The researchers assessed the condition of skeleton 244-8, using digital microscopes, scanning electron microscopes (SEM), and radiography (X-rays), and by examining the visual markers on the bone. They looked for evidence of sustained lesions, or damage on the bone, which they found on his vertebrae, ribs, sternum, pelvis, and other parts of the skeleton.

Figure 8

In the X-ray and photo image above of a rib, we can see the damage as noted by the arrows. The parts of the skeleton most affected by lesions were sections of the spine. The image below depicts an especially damaged thoracic vertebra.

Figure 9

The authors discussed four possible causes for the skeleton’s bone damage:

  • Metastatic organ cancer, or the rapid creation of abnormal cells that spread from the original site in the organs to other parts of the body
  • Multiple myeloma, a cancer of the plasma cells in bone marrow
  • Fungal infection
  • Taphonomic damage, or natural decay after death

Although very similar, the visual markers on bone differ slightly depending on the malady causing the damage. We can see in the image below of the tibia that taphonomic damage caused by insects is slightly more uniform in shape than lesions caused by cancer, and the holes continue straight through to the other side of the affected bone.

Figure 13

Based on the shape, size, and appearance of the lesions under X-ray, the authors surmised that the man suffered from metastatic cancer, originating in the man’s organs. However, since no soft tissue was preserved over time, it is nearly impossible to ascertain the exact location of skeleton 244-8’s primary tumor, which would have affected soft tissue like his organs.

Considering the decay caused by time, salt, and insects, the researchers were able to ascertain quite a lot about skeleton 244-8 based on their examinations of the skeleton. In addition to diagnosing him with metastatic cancer, researchers suggest that skeleton 244-8 was a young man between the ages of 25 to 35 who belonged to a middle-class Nubian family at the time of his death, based on the context of his burial.

With increasing advances in the technology used to examine subjects like skeleton 244-8, the inner secrets and pathologies held in places like the inside of bone become less of a mystery. With further study, we’ll be able to understand a little more about the environmental risk factors of skeleton 244-8’s own world: for instance, the possible use of fires in poorly ventilated mudbrick houses, or possible infectious diseases spread by parasites. By taking a closer look at human remains like skeleton 244-8, it may eventually be possible to see the effects of a disease not only of our time, but of considerable antiquity.

Citation: Binder M, Roberts C, Spencer N, Antoine D, Cartwright C (2014) On the Antiquity of Cancer: Evidence for Metastatic Carcinoma in a Young Man from Ancient Nubia (c. 1200BC). PLoS ONE 9(3): e90924. doi:10.1371/journal.pone.0090924

Image 1: pone.0090924

Image 2: pone.0090924

Image 3: pone.0090924

Image 4: pone.0090924

Image 5: pone.0090924

The post A Disease of Considerable Antiquity: Cancer Detected in a Nubian Skeleton appeared first on EveryONE.

The Power of the Claw: Not Your Average “Soft” Material

Sep blog-tiger cropped

Earlier this month we gave you cuddling between affectionate lions. Lest we become overwhelmed by the desire to cuddle one of these (albeit adorable) feline predators ourselves, here is a look at exactly what one of their clawed paws could do to us, including to one of our toughest components: bone. In a PLOS ONE study published earlier this month, researchers tested the ability of claws to scratch the surface of bone. The effects of claw damage are often overlooked because claws are made of a material softer than bone. Contrary to expectations, however, these researchers found that claws produced recognizable bone damage.

The setup was simple: let a Kansas zoo tiger participating in their enrichment program spend an afternoon leisurely playing with carefully nested cow thigh bones, also called femora. To ensure that the cow femora were only accessible to tiger claws and not to tiger teeth, researchers bolted femora down into a log that was narrowly hollowed out—preventing the big cat from sticking his snout in.

Sep blog- cow femora

The result: impressively lacerated cow femora. Once tiger playtime was over, researchers removed the log, unbolted the femora, and microscopically examined the bone. Four scratches were clearly visible upon the bone’s surface. The scanning electron microscope (SEM) image below further highlights the depths of the tiger claw handiwork.

Sep blog-fomora scratches microscope

In this particular gouge, the main diagonal chasm in the image, the gulf made by the tiger’s claw penetrated the outer covering and subadjacent bone into the bony matrix. As we can see, tiger claws can do some damage.

Damage done to bone, however, is for the most part attributed to the effects of a predator’s teeth and not its claws, the reason being that measures of scratch resistance adhere to a so-called Mohs scale of mineral hardness. The Mohs scale is graded, with talc (1) as the softest material and diamond (10) as the hardest. On the scale, harder materials damage softer materials, but not vice versa. And in our case, bones are, in fact, harder than claws. Claws are made of the protein keratin—the same stuff is in hair, wool, nails, horns, and hooves—which scores a meager 2.5 on the Mohs scale. Bone, on the other hand, scores a much more formidable 5.0.

The current research, however, shows that we can expand our understanding of scratch resistance and mineral hardness to include the effects of softer materials striking harder materials, as long as we consider the kinetic energy involved, like the action of a tiger swatting or grabbing with its paw. In essence, more could be going on in the fossil record than previously thought.

Paleontologist and PLOS ONE Section Editor Andy Farke points out in the PLOS ONE blog The Integrative Paleontologist that fossils inevitably resurface as imperfect objects, which is, in part, what makes them so interesting: These fossils bear the visible marks in postpartum decay of a long and varied history. When studying bone narratives, paleontologists encounter everything from water damage to the bore marks of little critters. Including big-critter claw marks in the repertoire of possible bone modifications broadens this narrative and evidences, as the researchers themselves so aptly put it, the power of the claw.

For more information from the paleontologist perspective, check out blog posts on this article in The Integrative Paleontologist  by Dr. Farke and National Geographic.

Citation:

Rothschild BM, Bryant B, Hubbard C, Tuxhorn K, Kilgore GP, et al. (2013) The Power of the Claw. PLoS ONE 8(9): e73811. doi:10.1371/journal.pone.0073811

Image 1: Tiger by Dave Stokes

Image 2: doi:10.1371/journal.pone.0073811

Image 3: doi:10.1371/journal.pone.0073811