Revolution in anatomy: organs and parts of the human body that scientists recently discovered (7 photos)

It would seem that the anatomy of the human body has been studied a long time ago. But no, research scientists are still finding new structures that no one had previously suspected.





The investments that large companies make in studying the physiology of the human body amount to hundreds of billions of dollars. This knowledge helps to understand the mechanisms of the body’s reactions to certain stimuli and to advance in the search for new drugs for serious diseases. However, it is surprising that over the past decade structures have been found in the body that no one knew about before. Let's talk about four of them.

Interstitium or system of cavities

In 2018, doctors at the Mount Sinai Medical Complex (USA) examined a patient with suspected cancer. To obtain a biopsy, the patient was examined using an endoscope. By placing a tiny microscope into the bile duct, doctors were able to examine not only the duct itself, but also the area adjacent to it. The surprised eyes of the doctors saw a space filled with cavities with liquid contents. These cavities were connected to each other.



The analysis showed that the system of cavities is part of the connective tissue of the submucosal layer; it connects the mucous and muscular membranes. During conventional histological analysis, this microorgan was not visible, and it was discovered only with the use of special reagents. The cavities turned out to be lined from the inside with cells similar to connective tissue cells. Surrounded by bundles of collagen, they were filled with fluid.





The study of this interstitium has shown that it plays the role of a kind of buffer that protects internal organs. Similar structures were later found in other places in the body: in the submucosal layers of the entire gastrointestinal tract, bladder and soft tissues around the bronchi and arteries. In a word, where the body is subject to constant compression. By the way, the term interstitium is not new, and it has been known in histology since approximately the mid-twentieth century. In particular, this extracellular matrix was previously found in the kidney and described as a structure that plays an important role in the reabsorption of water from the nephron tubules into the blood capillaries. However, interesting and important is the fact that the interstitium is found in other places in the human body.

If we assume that the interstitium temporarily stores fluids that ultimately enter the lymphatic system, then studying this organ will make it possible to understand the mechanism of spread of pathogenic structures (for example, cancer cells).

Dua layer

The cornea is the clear part of the eye that covers the pupil, iris, and the inside of the eyeball. As it turned out, until recently not all of its layers were known. In particular, the Dua layer, named after its discoverer, was only identified in 2013. Its thickness is only 15 microns, and therefore it became possible to detect this layer only using the latest technology.



Previously, it was believed that the cornea consists of five layers, but transplantologists, while performing operations, noticed that when the thickest layer (stroma) was separated, a certain structure, previously unknown, was present between it and Descemet’s membrane. Studying it showed that this new layer consists mainly of plates of collagen of the first type, located in the transverse, longitudinal and oblique directions. This structure gives it greater strength compared to other layers. Further study of the Dua layer will help in the treatment and prevention of corneal pathologies, as well as minimize complications after laser refractive surgery.



Lymphatic system of the meninges

There is a lymphatic system inside the brain - this fact was reliably established in 2015. It was previously thought that byproducts of brain metabolism entered the cerebrospinal fluid and from there into the bloodstream. However, in 2015 it was found that the lymphatic system of the brain is most directly involved in the accumulation and removal of these “rests” of brain activity.

Schemes of the lymphatic system: old - on the left and updated - on the right



This discovery was made thanks to five volunteers who were administered gadobutrol. The molecules of this dye are too small to leak from the blood vessels into the lymphatic vessels and at the same time large enough to overcome the blood-brain barrier, which protects the brain from unwanted intrusions of this kind. As a result, MRI images revealed an extensive network of lymphatic vessels. The dye was distributed throughout it in the dura mater. Through these vessels, colorless lymph containing immune cells and metabolic products flows from the brain to the cervical lymph nodes. White blood cells (leukocytes) also come there through the blood vessels. With their help, the lymph nodes cleanse immune cells and recycle them.

This important discovery will allow us to learn more about the mechanisms of brain function and will help in the treatment of neurological pathologies, for example, Alzheimer's disease, one of the causes of which is considered to be excessive accumulation of certain proteins. It is known that with age, the activity of the lymphatic system decreases, and, consequently, the risk of Alzheimer's disease increases. If scientists learn to monitor and correct the work of “self-cleaning the brain,” then the moment of manifestation of pathology can be delayed.

Transcortical capillaries

Thin blood vessels transporting stem cells have been found in long bones, such as the femur. Previously it was believed that at the ends of the bones there are vessels that allow blood to enter the bone marrow and return it back. Studies conducted on rodents confirmed these assumptions. However, during further experiments it was revealed that stem cells (in particular, hemocytoblasts - HSCs) enter the blood too quickly, which does not correspond to the throughput parameters of the vessels.



Researchers discovered tiny holes in the bones, and then blood stains, and came to the conclusion that the vessels communicate with the bone not only at its ends, but also along its length. This discovery sheds new light on the nature of bone fragility, which is commonly seen with age. It is quite possible that it can be explained by a decrease in the number of normally functioning capillaries, by protecting which, researchers will be able to improve the quality of human life.