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Obstructive Sleep Apnea Syndrome (OSAS) is a common sleep disorder and it defined as repetitive episodes of upper airway obstruction causing arousals and oxygen desaturation, usually leading to excessive daytime sleepiness, snoring and cardiovascular diseases. Other problems associated with OSA include poor memory, depressions, fatigue, morning headaches and dry mouth. OSA affects one of four men and one of 11 women in the world. There are several causes of OSA. Obesity, by narrowing the airway, is the most common cause of OSA.
Structural abnormalities such as micrognathia (small mandible), macroglossia (enlarged tongue), or enlarged tonsils or adenoids can be contributing factors. There is a relationship between upper airway anatomy and OSA. The upper airway is an extremely complicated structure that performs several different physiological function including deglutition, vocalization, and respiration. The dynamic biomechanical relationships among the upper airway muscles that allow these functions to occur are not well understood. The majority of computed tomography and magnetic resonance imaging studies indicate that wakefulness the upper airway of apneics is smaller than normals. In patients with sleep apnea, the size of upper airway structure are increased (soft tissue structure) or decreased (craniofacial structures). Increasing the size of soft tissue structure narrow the upper airway and predispose to airway closure during sleep. In 2002, the underlying pathogens of the increase in size of theses soft tissue structures surrounding the upper airway remains unknown, but possible etiological mechanisms include: edema from negative pressure generated in upper airway during sleep, obesity, injury and genetic factor. The craniofacial abnormalities (reduced mandibular body length, inferiorly positioned hyoid bond, and retroposition of the maxilla) are likely to be genetically determined, although gender and race may play a role. Cytokines play a role in the regulation of sleep. Cytokine is a large group of low molecular weight proteins that mediate many aspects of immunity, inflammation, tissue remodeling, and embryonic development. Interleukin-1 (IL-1) and tumor necrosis factor (TNF) are cytokine that promote non-rapid eye movements sleep under physiological and inflammatory conditions. Additional cytokines are also likely involved but evidence is insufficient to conclude that they are sleep regulatory substances. There are several treatments for OSA such as continuous positive airway pressure (CPAP), dental appliances and surgery. CPAP works as â€œpneumatic splintâ€Â, preventing upper airway collapse and obstruction. The level of pressure needed to prevent obstruction (apnea and snoring) varies from patient to patient and must be determined by a sleep laboratory polysomnogram CPAP titration study. Several mask interfaces are available such as nasal masks, nasal pillows, full face masks, and at least one oral mask. Dental appliances are devices which relieve obstruction by repositioning of the tongue or advancement of the mandible. The devices are most affective in patients with mild to moderate sleep apnea. Surgical treatment of OSA is for patient with severe OSA. For example, removing of enlarged tonsils and adenoids is frequently effective. A surgical operation on the back of the throat to remove redundant soft tissue in an attempt to increase the size of the upper airway can be performed. It usually involves removal of the part of the soft palate that hangs down in the back of the throat, as well as the tonsils if present, and other soft tissue if it is felt to be excessive. The operation is referred to as an uvulopalatopharyngoplasty (UPPP) and was initially described as an operation to improve heavy snoring. It is usually quite successful at decreasing the loudness of snoring but is not always successful at improving sleep apnea. There is currently no method that is widely available to predict which patients stand to benefit from this surgery.
Inflammation is a defense reaction of higher animals to the presence of any injurious stimulus. An irritant can be physical in nature, such as heat, or it can be chemical, or bacterial. Inflammation is an immune system response to protect the body from infection. Inflammation occurs when white blood cells migrate out of blood vessels into the infected area, where they act as phagocytes. There are two basic types of inflammation: acute and chronic. Acute inflammation is of short duration, which could be anything from a few minutes to a few days.
Such inflammation is caused by foreign substances entering the body, or by physical damage. A viral infection may also precipitate acute inflammation. Chronic inflammation, on the other hand, is long lasting. It may persist for weeks, months or even years. Chronic inflammation may be brought on by acute inflammation or it may be the result of an auto immune disease. There are two type of white blood cells (leukocytes): granulocytes which include neutrophil, eoinophil and basophil. Mononuclear cells which include lymphocyte and monocyte.
Neutrophils develop in the bone marrow and it provide an effective defense against bacterial and Fungal infection. They are motile phagocytes that find their target by chemotaxis. In very early inflammation, monocytes and macrophages release interleukin-1 (IL-1), tumor necrosis factor (TNF), and IL-6 (hepatocyte stimulating factor). Injury often results in a systemic reaction known as the acute phase response (APR). This response consists of a rapid physiologic reaction generated to deal with tissue damage. Clinically there is fever, increase in the plasma level of acute phase proteins (many of which are synthesized by stimulated hepatocytes), decreased appetite, and altered sleep pattern. The immune system is a wonderful and complex defensive system designed to recognize foreign material and render the material harmless. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own healthy cells and tissues in order to function properly. Detection is complicated as pathogens can evolve rapidly, producing adaptations that avoid the immune system and allow the pathogens to successfully infect their hosts.The cells of the adaptive immune system are special types of leukocytes, called lymphocytes. B cells and T cells are the major types of lymphocytes and are derived from hematopoietic stem cells in the bone marrow. B cells are involved in the humoral immune response, whereas T cells are involved in cell-mediated immune response.
Immunocytochemistry is a technique used to assess the presence of a specific protein or antigen in cells (cultured cells, cell suspensions) by use of a specific antibody, which binds to it, thereby allowing visualization and examination under a microscope. It is a valuable tool for the determination of cellular contents from individual cells. Antibodies are an important tool for demonstrating both the presence and the subcellular localization of an antigen. Cell staining is a very versatile technique and, if the antigen is highly localized, can detect as few as a thousand antigen molecules in a cell. In some circumstances, cell staining may also be used to determine the approximate concentration of an antigen, especially by an image analyzer. There are two type of antibody polyclonal and monoclonal. There are many methods to obtain immunological detection on tissues, including those tied directly to primary antibodies. A direct method involves the use of a detectable tag (e.g., fluorescent molecule, gold particles, etc., ) directly to the antibody that is then allowed to bind to the antigen (e.g., protein) in a cell.Alternatively, there are many indirect methods. In one such method, the antigen is bound by a primary antibody which is then amplified by use of a secondary antibody which binds to the primary antibody. Next, a tertiary reagent containing an enzymatic moiety is applied and binds to the secondary antibody. When the quaternary reagent, or substrate, is applied, the enzymatic end of the tertiary reagent converts the substrate into a pigment reaction product, which produces a color (many colors are possible; brown, black, red, etc.,) in the same location that the original primary antibody recognized that antigen of interest. Some examples of substrates used DAB (3,3'Diaminobenzidine). There is another methods which is unlabelled antibody-enzyme methods.