Free «Thymus» Essay Paper

External and internal factors change the cell cycle of a healthy person. The result is abnormal molecules and cells. Special blood cells and other tissue produce and maintain sufficient concentration of free molecules that recognize, bind, convert and excrete abnormal molecules and cells. Redistribution of particles and cells (immune surveillance) in all tissue of the body occurs through blood flow and lymph flow and transport through the blood-tissue barriers. The main regulator and coordinator of this activity is thymus. Thus, this paper will discuss thymus and its peculiar properties.

The Organ System

Thymus is the organ of lymphopoiesis of humans and many animal species in which maturation, differentiation and immunological “learning” of the immune system T-cells occur. Thymus is a part of organs of the immune system, or lymphoid organs. Immune system combines organs and tissue protecting the body from foreign cells or genetic substances entering organism from the outside or generated in an organism (Goldstein & Mackay, 2013).

 

Type of service

Type of assignment

Title of your paper *

Academic level

Pages

Timeframe

Spacing

Currency

  Order now

The organs of the immune system are the organs that are involved in the formation of cells engaged in the protective reaction of the organism: lymphocytes and plasma cells. Immune organs are constructed from lymphoid tissue, which represents a reticular stroma and lymphoid series cells located in its hinge: lymphocytes of different maturity; young and mature plasma cells; macrophages and other cell components (Goldstein & Mackay, 2013). The organs of the immune system include: bone marrow, spleen, clusters of diffuse lymphoid tissue located in the walls of hollow organs of the digestive, respiratory and urinary system (tonsils, lymphoid plaques of the small intestine, and solitary lymphoid nodules in the mucous membranes of internal organs), lymph nodes and thymus (Goldstein & Mackay, 2013).

Functionality

Bone marrow is the organ of blood and immune system at the same time. The cardinal feature of bone marrow is that it serves as the main source of blood stem elements for myeloid and lymphoid differentiation germs (Metcalf, 2012).

Spleen is located at the path of blood flow to the liver. Many important immunological reactions are carried out in spleen. For example, antigens, which circulate in the blood, fall into the spleen parenchyma and activate lymphocytes, promoting their conversion into plasma cells, which produce antibodies. Spleen macrophages phagocytose blood cells, primarily erythrocytes. Iron, which is released from hemoglobin by digestion of erythrocytes, is absorbed into the blood and re-used in the bone marrow (Metcalf, 2012).

There are solitary diffuse lymphoid clusters in the thickness of the mucosa and submucosa of the digestive system (the pharynx, esophagus, stomach, small and large intestine and gall bladder) and respiratory organs (larynx, trachea and large bronchi). They serve as “guard posts” throughout the length of these bodies, at different distance from each other and at different depth (Metcalf, 2012).

Thymus is a retrosternal organ, located in the upper anterior mediastinum. Thymus is the central organ of the immune system. T-lymphocytes, which are responsible for cell-mediated and humoral immunity, ripen out of hematopoietic stem cells in thymus. Thymus also secretes substances that affect the differentiation of T-lymphocytes (Goldstein & Mackay, 2013).

Stay Connected

Live Chat Order now

Mechanics

The functional activity of the thymus is mediated through the production of T lymphocytes. T lymphocytes have different functions. They form plasma cells, inhibit excessive reaction, maintain constancy of different forms of leukocytes, release lymphokines activate lysosomal enzymes and enzymes of macrophages and destroy antigens. Maturation of T lymphocytes in the thymus is performed by division of the lymphocytes, which have receptors for foreign antigens the body met in childhood. The formation of T lymphocytes takes place regardless of the presence of antigen and quantity of T lymphocytes in the blood (due to the impermeability of the histo-hematic barrier of thymus) and is determined by genetic mechanisms and age (Goldstein & Mackay, 2013).

Illnesses and Epidemiology

Pathology of the thymus is closely connected with the violation of immunogenesis. It can be represented by accidental involution, hyperplasia and hypoplasia.

Thymus decreases rapidly in size when accidental involution occurs. It is characterized by progressive disintegration of lymphocytes and phagocytes, followed by the collapse of the gland. In advanced cases, thymic tissue atrophies completely ahead of time, i.e. before the onset of puberty (Lavini, Moran, Morandi, & Schoenhuber, 2009).

Hyperplasia (overgrowth of tissue) occurs in the form of combined pathology. Along with it, there is hyperplasia of lymphoid tissue located elsewhere in the body, hypoplasia of the gonads and adrenal glands, obesity and narrowing of the arteries. The complex of these changes is characteristic of a particular type of constitution called thymic-lymphatic condition. It is characterized by excessive sensitiveness to immunization, infectious diseases, anesthesia, surgical intervention and other factors (Lavini et al., 2009).

Thymic hypoplasia is closely linked to the development of immunodeficiency pathologies of the nervous and endocrine systems, as well as malignant tumors of mesenchymal tissue. For example, children weakened by hypoplasia often die of pneumonia or sepsis (Lavini et al., 2009).  

There is also a thymus cancer, which refers to a group of rare tumors. The causes of the disease are poorly understood. It is characterized by rapid growth, infiltration and metastasis in the pericardium and pleura. The beginning of the disease has no symptoms. Later, when thymus is enlarged metastases compress the adjacent organs; there is respiratory distress, blue face, heart rhythm disturbances, and other attributes (Anastasiadis & Ratnatunga, 2009).

The group that is the most exposed to the thymus illnesses are children because thymus develops to fifteen years, and then it starts to develop in the opposite direction. Children with thymus malfunctions get sick more often since they are more susceptible to viral, infectious and autoimmune diseases.

The prevalence of the illnesses (involution, hyperplasia and hypoplasia) counts to approximately 150-200 people per 100000 population, except of thymus cancer that counts to approximately 5-10 people per 100000 of population (Lavini et al., 2009). 

Testing

People (especially children) that are frequently ill with inflammatory diseases should be screened for functional state of the thymus gland. Valuable information on the disease can be obtained by conducting ultrasound, magnetic resonance imaging and other manipulations (Lavini et al., 2009). Method of scintigraphy helps to detect the size of the tumor and metastases in thymus cancer. Also, mediastinoscopy is conducted for histological examination of the tumor (Anastasiadis & Ratnatunga, 2009).

Treatment

Endocrinologist, oncologist and surgeon are engaged in the treatment of the diseases of the thymus. One can use replacement and rehabilitation therapy in order to compensate the lack of functioning of the gland. For this purpose, doctors use transplantation of not only the thymus itself, but the bone marrow; some immunoglobulins and gland hormones are introduced into the body. During the medical treatment corticosteroid medicines are contraindicated because they have a depressing effect on the immune system (Lavini et al., 2009).

The treatment of thymus cancer is limited to surgical intervention followed by removal of the organ. In some cases, a chemotherapy and radiation therapy are carried out (Anastasiadis & Ratnatunga, 2009).

Prognosis

Prognosis within thymic-lymphatic condition is positive. A person with thymic-lymphatic condition is subject to dispensary observation to prevent infectious diseases. Great importance should be given to non-specific methods of strengthening the immune system, which include massage, special diet, limiting fat intake and healthy lifestyle (Lavini et al., 2009).

In its turn, prognosis of thymus cancer is largely determined by the severity of the disease, tumor size, degree of invasion into adjacent anatomical structures, and presence of metastases (Anastasiadis & Ratnatunga, 2009).

Conclusion

Thymus is a small endocrine gland located in the upper anterior mediastinum that is responsible for the formation of the immunity. Thymus has a stimulating effect on hormone influenced the development of T - cells in lymphoid tissue including the stroma. Thymus also participates in the complex defense response against foreign and disease-causing agents.

Thymus illnesses include accidental involution, hyperplasia, hypoplasia and thymus cancer. Prognosis is positive for most illnesses except thymus cancer, which depends on a number of factors.