The average human body contains approximately of them, predominantly concentrated in the neck, axillae, groin, thoracic mediastinum, and mesenteries of the GI tract. Relationship of the peritoneal folds to each other and to organs of the digestive system, Sagittal section showing the peritoneal folds. Recent Examples of lymphatic from the Web Scraping off your dead stratum corneum cells has no effect on your lymphatics or digestive system. It is exemplified by the lymph nodes , and the lymphoid follicles in tonsils , Peyer's patches , spleen , adenoids , skin , etc. Subscription or UK public library membership required. Arteries of the pelvis and right lower limb, Anterior and Inferior views Part 1. Secondary lymphedema is basically acquired regional lymphatic insufficiency, which may occur as a consequence of any trauma, infection, or surgical procedure that disrupts the lymphatic vessels or results in the loss of lymph nodes [ 8 ].
An Introduction to the Human Body
The decline of the thymus is thought to be the reason T-cell production decreases with age. The thymocytes then move to the medulla of the thymus, where further differentiation occurs. Positive and negative selection destroy a great number of thymocytes; only about 5 to 10 percent survive to exit the thymus. Those that survive leave the thymus through specialized passages called efferent outgoing lymphatics, which drain to the blood and secondary lymphoid organs.
The thymus has no afferent incoming lymphatics, which supports the idea that the thymus is a T-cell factory rather than a rest stop for circulating lymphocytes. In birds B cells mature in the bursa of Fabricius. The process of B-cell maturation was elucidated in birds—hence B for bursa. In mammals the primary organ for B-lymphocyte development is the bone marrow, although the prenatal site of B-cell differentiation is the fetal liver. Unlike the thymus, the bone marrow does not atrophy at puberty, and therefore there is no concomitant decrease in the production of B lymphocytes with age.
The secondary lymphoid organs serve two basic functions: The lymph nodes, or lymph glands, are small, encapsulated bean-shaped structures composed of lymphatic tissue.
Thousands of lymph nodes are found throughout the body along the lymphatic routes, and they are especially prevalent in areas around the armpits axillary nodes , groin inguinal nodes , neck cervical nodes , and knees popliteal nodes.
The nodes contain lymphocytes, which enter from the bloodstream via specialized vessels called the high endothelial venules.
T cells congregate in the inner cortex paracortex , and B cells are organized in germinal centres in the outer cortex. Lymph, along with antigens, drains into the node through afferent incoming lymphatic vessels and percolates through the lymph node , where it comes in contact with and activates lymphocytes.
Activated lymphocytes, carried in the lymph, exit the node through the efferent outgoing vessels and eventually enter the bloodstream, which distributes them throughout the body. The spleen is found in the abdominal cavity behind the stomach. Although structurally similar to a lymph node, the spleen filters blood rather than lymph.
One of its main functions is to bring blood into contact with lymphocytes. The functional tissue of the spleen is made up of two types of cells: The splenic artery enters the red pulp through a web of small blood vessels, and blood-borne microorganisms are trapped in this loose collection of cells until they are gradually washed out through the splenic vein.
The white pulp contains both B and T lymphocytes. T cells congregate around the tiny arterioles that enter the spleen, while B cells are located in regions called germinal centres, where the lymphocytes are exposed to antigens and induced to differentiate into antibody -secreting plasma cells. Another group of important secondary lymphoid structures is the mucosa-associated lymphoid tissues. These tissues are associated with mucosal surfaces of almost any organ, but especially those of the digestive, genitourinary, and respiratory tracts, which are constantly exposed to a wide variety of potentially harmful microorganisms and therefore require their own system of antigen capture and presentation to lymphocytes.
Other, less-organized regions of the gut also play a role as secondary lymphoid tissue. The host of secondary lymphoid organs provides a system of redundancy for antigen sampling by the cells of the immune system.
Removal of the spleen, selected lymph nodes, tonsils, or appendix does not generally result in an excessive increase in disease caused by pathogenic microorganisms. However, the importance of the primary lymphoid organs is clear. For example, two autoimmune diseases, DiGeorge syndrome and Nezelof disease, result in the failure of the thymus to develop and in the subsequent reduction in T-cell numbers, and removal of the bursa from chickens results in a decrease in B-cell counts.
The destruction of bone marrow also has devastating effects on the immune system , not only because of its role as the site of B-cell development but also because it is the source of the stem cells that are the precursors for lymphocyte differentiation. We welcome suggested improvements to any of our articles.
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The Editors of Encyclopaedia Britannica. Read More on This Topic. Learn More in these related Britannica articles: Lymphatic capillaries form a network just inside the renal capsule and another, deeper network between and around the renal blood vessels.
Few lymphatic capillaries appear in the actual renal substance, and those present are evidently associated with the connective tissue framework, while the….
The lymph vessels develop independently in close association with the veins. Linkages produce the thoracic duct, which is the main drainage return for lymph. Masses of lymphocytes accumulate about lymphatic vessels and organize as lymph nodes. The spleen has somewhat similar tissue, but….
Blood vessels, lymphatic vessels, and nerves. The deep lymphatic system originates around the conductive airways and arteries and converges into vessels that mostly follow the bronchi and arterial vessels into the mediastinum. More About Lymphatic system 11 references found in Britannica articles Assorted References major reference In lymph study by Sabin In Florence Rena Sabin anatomy and physiology respiration adenoids In adenoids respiratory system In human respiratory system: Blood vessels, lymphatic vessels, and nerves embryological development In prenatal development: On the other hand, distant effects will arise when the body's resistance has more or less broken down: This will cause an inevitable deterioration of the body's defense power with a concomitant promotion of malignant growth.
Another researcher, Hal Huggins, DDS, has shown that the toxins liberated by infected root canalled teeth are almost times more toxic than botulism. Botulism is the most toxic substance known. Austrian researchers have exhaustively studied the finer details of the entire dental structure. They have established that there is a lively metabolic interchange between the interior and exterior milieu of the tooth, and that this two-way process takes place along many thousands of hyperfine, capillary canals joining the pulp cavity to the exterior surface of the tooth.
Very careful conservative measures may possibly seal off the vertical central dentinal canal, but it will never reach the lateral "twigs" branching off from this tube.
Nor can it ever close off the innumerable capillary canals. Some protein will always remain in these secondary spaces. If this protein becomes infected, toxic catabolic products, such as thio-ethers, thio-ethanols and mercaptans will be produced, and conveyed into the organism.
In , it was established by W. Meyer Goettingen that within devitalized teeth the dentinal canals and dental capillaries contain large microbial colonies. The toxins produced by these microbes in a tooth with a root filling can no longer be evacuated into the mouth, but must be drained away through the cross-connections and unsealed branches of the dentinal and capillary canals into the marrow of the jawbone.
From there, they are conveyed to the tonsils, and thus the flow systems of the body. In fact, the conservative treatment may literally convert a tooth into a toxin producing "factory". Bartelstone USA and Djerassi Bulgaria have reported that endodental exchange may also take place in the opposite direction. If radio-iodine, I, is deposited in an evacuated pulp cavity which is then sealed off with a filling, the iodine will appear in the thyroid some twenty hours later, as can be demonstrated by taking a scintograph of the thyroid region.
Similarly, dyes can be washed out of a sealed pulp cavity. Any substance produced by any of the structures in the oral cavity, teeth, gums, tonsils, will be drained by the lymphatic system and carried directly to the thyroid gland. The close interlacing of the lymphatic and endocrine systems in the head, make it unavoidable that brain cells are more intensively toxified by the circulating focogenous agents and may suffer particularly heavy damage.
The lymph ducts of the head region join Waldeyer's tonsillar ring, and if there is such congestion, waste fluids will be pressed through the porous base of the skull into the lymphatic spaces of the brain. Toxogenous changes, especially within autonomic nuclei, are regularly found in cancer patients, as verified in the 's by Muehlmann USSR , and they may be a consequence of a life-long inhibition of cerebral aerobiosis due to focogenous intoxication. All these findings prove conclusively that within solid dental structures, there may proceed an unimpeded substantial interchange in either direction.
Consequently, odontogenic toxins, wherever they may have been produced, are able to diffuse and circulate within the organism.
The German study group of Eger-Miehlke has investigated the pathogenic significance of these "endotoxins".
They examined the changes in healthy experimental animals after injection of accurately defined, minimal quantities of the endotoxins from an odontogenous granuloma. A single injection of a minimal dose seemed to develop a defense-activation effect. But after repeated injections, there was severe liver damage, and the animals died within weeks.
Apart from the fatal liver damage, inflammatory and degenerative changes were found in all other organs, especially in the joints, muscles, and blood vessels. These results brought clear experimental proof for the first time that focogenic toxins act as causal agents for severe diseases in animals corresponding to similar chronic conditions in man.
The most dangerous of all odontogenous toxins are undoubtedly the thio-ethers, for instance dimethylsulfide. Other severe toxins from root-canal bacteria include thio-ethanols and mercaptans which have been found in the tumors of women who have breast cancer. These toxins drain through the lymphatic system down the cervical chain of lymph nodes and ultimately in to the breast tissue.
In a series of tests performed at Dr. Issel's clinic it was observed that patients with odontogenous and tonsillar foci had a heightened level of dimethylsulfide in their blood. After intensive treatment of the foci, this level returned to normal in just a few days. Thio-ethers are closely related, both in their structure and their effect, to mustard gas and other poison gases used in the First World War.
To give you an idea of its poisonous effects the following is a list of the major symptoms:. Thio-ethers are "partial" antigens, haptens, and thus they also tend to combine with the normal proteins in the body, "denaturizing" them. Such denatured proteins become "non-self" agents, which the body must deal with as such. The production of antibodies adapted to the situation will be provoked, and they will home in on the target antigens wherever they are.
The process of "auto-aggression" will be set in motion: Extensive structural cellular damage will result and help create the environment for cancer. Druckrey Heidelberg found among other things that transformation of a normal cell into a malignant cell requires a certain quantity of a carcinogen -the carcinogenic minimum dose. It does not matter whether this quantity is supplied in a single dose or in a number of smaller doses, because the toxic effects of each dose are stored, and accumulate without loss.
The carcinogens held primarily responsible for the development of spontaneous cancer in man are those: Which inhibit the aerobiosis even in minimal quantities without at the same time immediately destroying the cell, and, which are constantly present in the organism in this minimal concentration of either endogenous or exogenous origin; they can therefore accumulate during the normal life expectancy gradually and unnoticeably until the total quantity necessary for malignization is reached.
Mercury Each year in the U. Scientific studies have concluded that the amalgam is the source for more than two thirds of the mercury in our human population. On a daily basis each amalgam releases on the order of 10 micrograms of mercury into the body. This mercury either accumulates in the body or is excreted via urine and feces into our wastewater systems. After death, the accumulated mercury is released to the environment via either cremation or burial. Environmental mercury pollution is also caused by dentists who remove old fillings.
According to the observations made by the internationally recognized medical researcher, Yoshiaki Omura, MD, all cancer cells have mercury in them. Since mercury is the second most toxic substance on this planet, its presence provides a strong initiating factor for disrupting cell function. In the article, Nolte states that, "The wave spectrum of mercury contains more than thirteen wavelengths, whereas only one or two frequencies or wavelengths are usually observed for the other heavy or noble metals.