Cushing’s syndrome is defined as the hypersecretion of a class of steroid hormones known as corticosteroids such as cortisol. These substances, which are involved in anti-inflammatory and metabolic activities, are secreted by the cortex of the adrenal glands. The two triangle-shaped, suprarenal glands are composed of two layers; the outer portion is the adrenal cortex and the inner region is the adrenal medulla. The adrenal cortex is signaled to secrete corticosteroids in response to the hormone, adrenocorticotrohpic hormone (ACTH), released by the pituitary gland, which is first signaled by corticotropin-releasing hormone (CTH) originating in the hypothalamus. In view of this pathway, Cushing’s syndrome may be the result of dysfunction in several areas of the body.
There are several different causes for Cushing’s syndrome. Most cases are iatrogenic in nature, meaning they are induced in patients undergoing steroid therapy. Fewer cases are endogenous, in which the body itself produces more cortisol than is needed usually due to a tumor. The two most common sites for tumors are the pituitary gland and the adrenal cortex. “Tumours that develop inside the pituitary or adrenal gland are usually non-cancerous. Other than the symptoms of Cushing’s syndrome, they don't usually pose a serious threat to health.” (nhsuk). Sometimes, a tumor forms inside the lung and produces the ACTH hormone. “It is concluded that certain tumors autonomously elaborate an ACTH-like substance that stimulates the adrenal glands to secrete large quantities of corticosteroids …” (Clifton, 1962). Further, “Occasionally, tumours developed from tissues considered as non endocrine may express a given hormone gene and some even secrete large amounts of biologicall...
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...y M. Carlton. St. Louis: Mosby Elsevien, 2009. 322-23. Print.
Meador, C.L., Liddle, G.W., Island, D.P., Nicholson, W.E., Lucas, C.P., John, J.G., and John A. Luetscher. “Cause of Cushing's Syndrome in Patients with Tumors Arising from ‘Nonendocrine’ Tissue.” The Journal of Clinical Endocrinology & Metabolism 22.7 (1962): 693-703. Print.
Messager, M., Carrière, C., Bertagna, X., and Y.D. Keyzer. “RT-PCR Analysis of Corticotroph- associated Genes Expression in Carcinoid Tumours in the Ectopic-ACTH Syndrome.” European Journal of Endocrinology. 154.1 (2006): 159-66. Print.
NHS Choices. Directgov, 2011. Web. 16 February 2012. .
NMIHI.com Online Health Information. New Medical Information and Health Information (NMIHI). 2011. Web. 16 February 2012. .
The exact cause of hypothalamic tumors is not known. It is likely that they result from a combination of genetic and environmental factors. In children, most hypothalamic tumors are gliomas. Gliomas are a common type of brain tumor that results from the abnormal growth of glial cells, which are a type of cells that support nerve cells. Gliomas can occur at any age
The hypothalamus releases corticotrophin (CHR), which is a chemical messenger. CHR stimulates the pituitary gland to release adrenal corticotrophin (ACTH). ACTH, which is released into the blood, then signals the adrenal gland. When the adrenal gland receives ACTH, it is the chemical signal for cortisol production. In a normal system, cortisol (an anti-inflammatory) production would stop after being released, but if there is a break down in the process, cortisol production continues, leading to Cushing’s disease....
Dupuytren’s Disease, also known as Dupuytren’s Contractures, palmar fascitis, Viking Disease, or palmar fibromatosis, is a hand deformity that usually develops slowly, usually over years. This disease is caused by the thickening and contraction of the palmar fascia. As the disease progresses, nodules progress to form longitudinal bands referred to as cords on the palmar fascia, and the finger gradually loses extension, with contractures that draw one or more fingers into flexion at the metacarpophalangeal (MCP) joint, proximal interphalangeal (PIP) joint, or both of these joints.
Flaccid dysarthria results from damage to the lower motor neurons (LMN) or the peripheral nervous system (Hageman, 1997). The characteristics of flaccid dysarthria generally reflect damage to cranial nerves with motor speech functions (e.g., cranial nerves IX, X, XI and XII) (Seikel, King & Drumright, 2010). Lower motor neurons connect the central nervous system to the muscle fibers; from the brainstem to the cranial nerves with motor function, or from the anterior horns of grey matter to the spinal nerves (Murdoch, 1998). If there are lesions to spinal nerves and the cranial nerves with motor speech functions, it is indicative of a lower motor neuron lesion and flaccid dysarthria. Damage to lower motor neurons that supply the speech muscles is also known as bulbar palsy (Pena-Brooks & Hedge, 2007). Potential etiologies of flaccid dysarthria include spinal cord injury, cerebrovascular accidents, tumors or traumatic brain injury (Pena-Brooks & Hedge, 2007). Possible congenital etiologies of flaccid dysarthria include Moebius syndrome and cerebral palsy. Flaccid dysarthria can also arise from infections such as polio, herpes zoster, and secondary infections to AIDS (Pena-Brooks & Hedge, 2007). Additionally, demyelinating diseases such as Guilian-Barre syndrome and myotonic muscular dystrophy can also lead to flaccid dysarthria (Pena-Brookes & Hedge, 2007). The lower motor neuron lesion results in loss of voluntary muscle control, and an inability to maintain muscle tone. Fasciculations, or twitching movements, may occur if the cell body is involved in the lesion (Seikel et. al., 2010). The primary speech characteristics of flaccid dysarthria include imprecise consonant production, hypernasal resonance, breathiness, and harsh voice (...
CAH is an autosomal recessive genetic disorder and males and females are affected in equal numbers. Chromosome 6 is where the group of genes lie that causes the most common forms of CAH. Adrenocorticotropic hormones (ACTH) are released by the anterior lobe in the pituitary gland. Its role is to act on cells of the adrenal cortex which then synthesizes corticosteroids and cortisol. However, those with CAH have insufficient amounts of the enzyme 21-hydroxylase, needed to convert 17-hydroxyprogesterone (17-OHP) into cortisol.
Chronic Wasting Disease is a highly transmissible, deadly neurodegenerative disease that affects cervids in North America (Belay et al., 2004; Saunders et al., 2012). There are only four types of cervid that are known to get this disease which include elk, mule deer, white-tailed deer, and moose (Chronic Wasting Disease Alliance). It has been classified has a transmissible spongiform encephalopathy (TSE), otherwise known as a prion disease (Belay et al., 2004). A prion is an irregular, pathogenic agent that causes abnormal folding of specific proteins called prion proteins. These proteins are mostly located in the brain (Chronic Wasting Disease Alliance). The abnormal folding of this protein causes neurodegenerative diseases in a variety of species including humans, sheep, cattle, and deer (Abrams et al., 2011).
Addison’s disease is a disorder of the endocrine system. It is a hormonal disorder that can strike anyone, any gender at any age. Addison’s disease has also been called Adrenal Insufficiency (hypocortisolism) because the root of the disease is in the adrenal gland not producing enough of the hormone cortisol, or sometimes not enough of the hormone aldosterone to satisfy the body’s needs.
The hormones produced from the endocrine system come from a wide range of different places. Among those responsible for hormone production are the glands and a few organs as well. The glands that are involved are the pituitary, thyroid, thymus, parathyroid, and adrenal. The organs, which also play a vital part, are the pancreas, gonads, kidneys, heart, and parts of the digestive tract. All these different glands or organs work together in the production of certain hormones. Those produced in one location will almost always have an effect on many other areas of the body, not just the surrounding tissues.
Hypothyroidism is a chronic disease that is part of the endocrine system. Hypothyroidism is due low or lack of tri-iodothryonine (T3) and tetraiodothyronine (T4) thyroid hormones being produced by the thyroid gland. The lack of thyroid hormones could be due to iodine or thyroid stimulating hormone (TSH) deficiency or underactive thyroid gland (Sherwood, 2012). Thyroid hormones T3 and T4 are involved in almost every part of the body. It is ten times more prevalent in female than male, which affects about 4.6% of U.S population (Lellis-Santos et al, 2011). In the most cases, the symptoms are cold intolerance, fatigue, bradycardia and weight gain. Depending on the cause on hypothyroidism, a goiter may develop, which is the enlargement of the thyroid gland. In most cases taking thyroid hormone supplement is an effective treatment.
...ll gland at the base of the brain, under the control of the hypothalamus, can signal the adrenal glands to increase the production of stress hormones such as cortical and adrenaline even further.
Polycystic Ovaries Syndrome (PCOS) is an ovulation disorder and infertility that occurs in many women. Polycystic ovaries syndrome dates back to 1845 where it was described in a French manuscript as being “changes in the ovaries”. It was called “sclerocystic”. Polycystic ovaries syndrome is a problem that occurs in with the ovaries. A “polycystic ovary is characterized as being a tough, thickened, shiny white covering overlying a layer of many small cysts just under the ovarian surface.” (Thatcher, 10). That was the description that was found in the French manuscript and is still being used to this day for doctors to define polycystic ovaries. A wedge resection in the early 1900’s was the first form of treatment for this syndrome. PCOS involves more than just the ovaries filled with small cysts. Polycystic Ovaries Syndrome causes infertility in women.
The thyroid gland is found in the front of the neck and produces two main hormones. The hormones are called thuroxine (T4) and Triiodothyronine (T3). Together these hormones regulate the body’s metabolism by increasing energy use in cells, regulate growth and development, help to maintain body temperature and aid in oxygen consumption. These two hormones are regulated by hormones produced by the hypothalamus and pituitary gland. The hypothalamus senses changes in body’s metabolic rate and releases a hormone known as thyropin-releasing hormone (TRH). This hormone then flows through connecting vessels to the pituitary gland which signals it to release another hormone. This hormone is known as thyroid-stimulating hormone (TSH). TSH then makes its way to the bloodstream until it reaches the thyroid where it is then signaled to activate T3 and T4 production [1]. This mechanism is controlled by a negative feedback loop meaning that when there is a sufficient amount of thyroid hormones in the blood stream, this will signal back to stop production of thyroid stimulating hormones. Complications occur when the thyroid hormones keep increasing even though there is already a sufficient amount of T3 and T4 in the blood stream. This process of over expression of thryroid hormones is known as hyperthyroidism. Hyperthyroidism is a general term that includes any disease that has a consequence of an overabundance of thyroid hormones. Hyperthyroidism is a general term but there are many variant diseases that are in the hyperthyroidism category. These diseases include diffuse toxic goiter, Basedow’s disease, thyrotoxicosis, Parry’s and Graves’ disease.
I was in the laboratory yesterday talking with my fellow colleagues when one of them suddenly brought up the peculiar observations he had lately found in the anatomy of a deceased hand. I was intrigued by his discussion of his discoveries and asked him if I could help him dissect it even more. He agreed and led me to his table where the hand was laid out on the table before us. My colleague told me the hand had been deceased for two days, but by the looks of it the hand looked to have been deceased for weeks.
Pheochromocytoma is a rare tumor which is formed in chromaffin cells of the adrenal glands. Pheochromocytomas are also known as adrenal chromaffin tumors (1). Chromaffin cells are found in the medulla of the adrenal glands (Figure 1). The adrenal glands located just above the kidneys. These cells receive neuronal messages from the brain via neurotransmitters and, as a result of these messages, release hormones in to the bloodstream (Figure 2). The main catecholamines produced in the adrenal glands are dopamine, norepinephrine, and epinephrine (also known as adrenaline) (1). Pheochromocytomas cause the adrenal glands to make too much of these hormones, which are called catecholamines. Adrenal glands with pheochromocytomas produce excess catecholamines, which can cause high blood pressure or hypertension (1). High blood pressure that goes untreated can lead to a variety of severe health problems including heart disease and stroke. Typical symptoms of pheochromocytomas include headaches, excessive sweating, pounding of the heart, pain in the chest, and a feeling of anxiety (1).
The endocrine system is composed by a group of glands that secrete hormones for the secretion of a specific organ and the result of this cycle will contribute to of physiological and behavioral activities. The circulatory system makes a connection with the hormones secreted because it helps them to travel around the human body in a very short time. The endocrine glands that secrete the hormones that target specific hormones consist of the pituitary gland, thyroid gland, adrenal gland, pancreas, ovaries and testes. However, they are secondary organs part of the body system such as the kidney, liver, and heart. The kidney in particular secretes endocrine hormones such as renin and erythropoietin (EPO).