Thymus Gland 2
When asked what the thymus gland does for the body, many people would be hard pressed for an answer. They would know that they had heard of it before, but they would be unsure of its job in the body. The importance of this gland has to do with the immune system and what it creates. It is also important for the dental hygienist to know about this gland because of its importance in the oral cavity. The thymus gland is a rather interesting gland in our bodies; it does most of its work while we are young and then shrinks, as we get older. In regards to the HIV-infected patient, the product of the thymus gland is extremely important. Different things including nutrition, pollution, and antiretroviral treatment may alter the function and size of the thymus gland.
The thymus gland is an endocrine gland that is part of the immune system (Fehrenback & Herring, 2002). In this gland, T-lymphocytes are created, which are the majority of the white blood cells in the immune system (Fehrenback & Herring, 2002). The Taber’s Cyclopedic Medical Dictionary defines the thymus gland as being “found in the mediastinal cavity anterior to and above the heart and being made up of two fused lobes, each containing multiple lobes, which are divided into an outer cortex and an inner medulla” (2001). Without the thymus gland helping the immune system, our bodies would not be able to defend against all of the millions of different microbes that could invade and attack the body.
Under normal circumstances, the thymus gland creates most of the T-lymphocytes before puberty. When this gland begins to shrink, the activity from the gland also shrinks. There has been, however, some research that the thymus gland does not shrink from old age, but from chronic illness, poor nutritional habits, pollution, and radiation to prevent sudden infant death syndrome (Silver, 2002). Silver also found that there is now evidence that nutrients like vitamin C, vitamin E, zinc, and selenium help to protect the thymus from shrinking and that they may even make the thymus gland larger and increase the glands’ function (2002).
Kolte, Dreves, Ersboll, Strandherg, Jeppesen, Nielson, Ryder, & Nielson compiled a vast amount of research to determine if there was an association between larger thymic size and higher thymic output. Kolte et.al also found that a large thymus gland was beneficial to patients and that a larger thymus gland represented a higher degree of thymopoiesis and may be associated with a better prognosis for the HIV-infected patient (2002). Tabor’s Cyclopedic Medical Dictionary defined “thymopoietin as a hormone that the thymus gland secretes and which helps the thymocytes to mature and respond to specific antigenic stimuli”.
As with Kolte et. al, Delgado, Leal, Ruiz-Mateos, Martinez-Moya, Rubio, Merchante, De la Rosa, Sanchez-Quijano, & Lissen questioned the occurrence of increasing the thymus glands activity to help the immune system with illnesses like HIV. Delgado et. al was able to find evidence that an antiretroviral-treated thymus may show an increase in activity (2002).
The thymus gland may be known as the incredibly shrinking thymus gland, but it continues its usefulness well into adulthood. Kolte et. al suggests findings that the adult thymus gland is functional to a certain extent and is involved in reconstituting the immune function in HIV- infected patients (2002). It is thought that by developing new ways to increase the thymus gland it may be beneficial to HIV-infected patients (Kolte et. al, 2002). A study done in 1998 in UT southwestern shows that the thymus gland continues to produce T-cells throughout life (Morrison, 2001). Hayes & Hale also found that the thymic output in normal people also continues into adulthood (1999).
Through way of the thymus gland, T-lymphocytes or white blood cells are created. The importance for the dental hygienist to know this is because it is an important feature for the entire body, including the oral cavity. The reason that this is so important is because the white blood cells are the defenders of the immune system. When there is an infection or disease, the white blood cells rush to the location of the infection or disease. This is what occurs in inflammation. In regards to the oral cavity, if there were infection or disease of the ginviva, it would be termed gingivitis because the white blood cells would rush to the scene and then there would be inflammation in the gingiva. The inflammation is merely the white blood cells trying to defend the body against the microbes or bacteria that are attacking the gingiva.
The thymus gland has been shown to be an integral component of the immune system. Within this gland, T-lymphocytes are created, which are the defenders of the immune system. Throughout this paper it has been shown that the thymus gland may decrease in size and function, but it can also be made to increase in size and function as well. Its importance has also been shown to continue well into adulthood and by serving the oral cavity.
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