|
Parathyroid Disease
Many conditions are associated with disorders of the function of the parathyroid gland. Some disorders may be purely anatomical resulting in an enlarged gland which will raise concern. Such benign disorders, such as parathyroid cyst, are not discussed here. Parathyroid diseases can be divided into those causing hyperparathyroidism, and those causing hypoparathyroidism. Comparison Hyperparathyroidism and related conditions The single major disease of parathyroid glands is overactivity of one or more of the parathyroid lobes, which make too much parathyroid hormone, causing a potentially serious calcium imbalance. This is called hyperparathyroidism; it leads to hypercalcemia, kidney stones, osteoporosis, and various other symptoms. Hyperparathyroidism was first described in 1925 and the symptoms have collectively become known as " moans, groans, stones, and bones." By far, the most common symptom is fatigue, but depression, memory loss, and bone aches are also very common. Primar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parathyroid Adenoma
A parathyroid adenoma is a benign tumor of the parathyroid gland. It generally causes hyperparathyroidism; there are very few reports of parathyroid adenomas that were not associated with hyperparathyroidism. A human being usually has four parathyroid glands located on the posterior surface of the thyroid in the neck. In order to maintain calcium metabolism, the parathyroid glands secrete parathyroid hormone (PTH) which stimulates the bones to release calcium and the kidneys to reabsorb it from the urine into the blood, thereby increasing its serum level. The action of calcitonin opposes PTH. When a parathyroid adenoma causes hyperparathyroidism, more parathyroid hormone is secreted, causing the calcium concentration of the blood to rise, resulting in hypercalcemia. Signs and symptoms The first signs of a parathyroid adenoma and the resulting primary hyperparathyroidism can include bone fractures and urinary calculi such as kidney stones. Often, a parathyroid adenoma is diagnos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrograph
A micrograph is an image, captured photographically or digitally, taken through a microscope or similar device to show a magnify, magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a microscope but is only slightly magnified, usually less than 10 times. Micrography is the practice or art of using microscopes to make photographs. A photographic micrograph is a photomicrograph, and one taken with an electron microscope is an electron micrograph. A micrograph contains extensive details of microstructure. A wealth of information can be obtained from a simple micrograph like behavior of the material under different conditions, the phases found in the system, failure analysis, grain size estimation, elemental analysis and so on. Micrographs are widely used in all fields of microscopy. Types Photomicrograph A light micrograph or photomicrograph is a micrograph prepared using an optical microscope, a process referred to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jansen's Metaphyseal Chondroplasia
Jansen's metaphyseal chondrodysplasia (JMC) is a disease that results from ligand-independent activation of the type 1 ( PTH1R) of the parathyroid hormone receptor, due to one of three reported mutations (activating mutation). JMC is extremely rare, and as of 2007 there are fewer than 20 reported cases worldwide. There are only 2 known families, from Dubai and Texas, in which the disease was passed from mother to daughter (Texas), and from a mother to her 2 sons (Dubai). Presentation & Genetics Blood levels of parathyroid hormone (PTH) are undetectable, but the mutation in the PTH1R leads to auto-activation of the signaling as though the hormone PTH is present. Severe JMC produces a dwarfing phenotype, or short stature. Examination of the bone reveals normal epiphyseal plates but disorganized metaphyseal regions. Hypercalcemia (elevated levels of calcium in the blood) and hypophosphatemia (reduced blood levels of phosphate), and elevated urinary calcium and phosphate, are genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parathyroid Hormone Receptor
There are two known parathyroid hormone receptors in mammals termed PTH1R and PTH2R. These receptors bind parathyroid hormone and are members of the GPCR family of transmembrane proteins. * parathyroid hormone 1 receptor (PTH1R) is the classical PTH receptor, is expressed in high levels in bone and kidney and regulates calcium ion homeostasis through activation of adenylate cyclase and phospholipase C. * parathyroid hormone 2 receptor (PTH2R) is expressed primarily in the central nervous system, pancreas, testis, and placenta The placenta (: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas, and waste exchange between .... References External links * * G protein-coupled receptors {{transmembranereceptor-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudopseudohypoparathyroidism
Pseudopseudohypoparathyroidism (PPHP) is an inherited disorder, named for its similarity to pseudohypoparathyroidism in presentation. It is more properly Albright hereditary osteodystrophy, although without resistance of parathyroid hormone (PTH), as frequently seen in that affliction. The term is used to describe a condition where the individual has the phenotypic appearance of pseudohypoparathyroidism type 1a, but has (unexpected for the phenotype) normal labs, including calcium and PTH. It can be considered a variant of Albright hereditary osteodystrophy (pseudohypoparathyroidism type 1A), as they present with the same constellation of signs and symptoms, including short stature, brachydactyly, subcutaneous calcification, and obesity. Presentation Pseudopseudohypoparathyroidism can be best understood by comparing it to other conditions: Hormone resistance is not present in pseudopseudohypoparathyroidism. Short stature may be present. Obesity is less common in pseudopseu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudohypoparathyroidism
Pseudohypoparathyroidism is a rare autosomal dominant genetic condition associated primarily with resistance to the parathyroid hormone. Those with the condition have a low serum calcium and high phosphate, but the parathyroid hormone level (PTH) is inappropriately high (due to the low level of calcium in the blood). Its pathogenesis has been linked to dysfunctional G proteins (in particular, Gs alpha subunit). Pseudohypoparathyroidism is a very rare disorder, with estimated prevalence between 0.3 and 1.1 cases per 100,000 population depending on geographic location. Types Types include: ;Type 1a : Has a characteristic phenotypic appearance ( Albright's hereditary osteodystrophy), including short fourth and fifth metacarpals and a rounded facies. It is most likely an autosomal dominant disorder. It is also associated with thyroid stimulating hormone resistance. Caused by GNAS1 mutation. ; Type 1b : Lacks the physical appearance of type 1a, but is biochemically similar. It i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoparathyroidism
Hypoparathyroidism is decreased function of the parathyroid glands with underproduction of parathyroid hormone (PTH). This can lead to low levels of calcium in the blood, often causing cramping and twitching of muscles or tetany (involuntary muscle contraction), and several other symptoms. It is a very rare disease. The condition can be inherited, but it is also encountered after thyroid or parathyroid gland surgery, and it can be caused by immune system-related damage as well as a number of rarer causes. The diagnosis is made with blood tests, and other investigations such as genetic testing depending on the results. The primary treatment of hypoparathyroidism is calcium and vitamin D supplementation. Calcium replacement or vitamin D can ameliorate the symptoms but can increase the risk of kidney stones and chronic kidney disease. Additionally, medications such as recombinant human parathyroid hormone or teriparatide may be given by injection to replace the missing hormone. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronic Kidney Disease
Chronic kidney disease (CKD) is a type of long-term kidney disease, defined by the sustained presence of abnormal kidney function and/or abnormal kidney structure. To meet criteria for CKD, the abnormalities must be present for at least three months. Early in the course of CKD, patients are usually asymptomatic, but later symptoms may include pedal edema, leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications can relate to hormonal dysfunction of the kidneys and include (in chronological order) Hypertension, high blood pressure (often related to activation of the renin–angiotensin system), renal osteodystrophy, bone disease, and anemia. Additionally CKD patients have markedly increased Cardiovascular disease, cardiovascular complications with increased risks of death and hospitalization. CKD can lead to kidney failure, end-stage kidney failure requiring kidney dialysis or kidney transplantation. Causes of chronic kidney disease include diabetic ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fine-needle Aspiration
Fine-needle aspiration (FNA) is a diagnostic procedure used to investigate lumps or masses. In this technique, a thin (23–25 gauge (0.52 to 0.64 mm outer diameter)), hollow needle is inserted into the mass for sampling of cells that, after being stained, are examined under a microscope (biopsy). The sampling and biopsy considered together are called fine-needle aspiration biopsy (FNAB) or fine-needle aspiration cytology (FNAC) (the latter to emphasize that any aspiration biopsy involves cytopathology, not histopathology). Fine-needle aspiration biopsies are very safe for minor surgical procedures. Often, a major surgical (excisional or open) biopsy can be avoided by performing a needle aspiration biopsy instead, eliminating the need for hospitalization. In 1981, the first fine-needle aspiration biopsy in the United States was done at Maimonides Medical Center. The modern procedure is widely used to diagnose cancer and inflammatory conditions. Fine needle aspiration is g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CT Scan
A computed tomography scan (CT scan), formerly called computed axial tomography scan (CAT scan), is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers or radiology technologists. CT scanners use a rotating X-ray tube and a row of detectors placed in a gantry (medical), gantry to measure X-ray Attenuation#Radiography, attenuations by different tissues inside the body. The multiple X-ray measurements taken from different angles are then processed on a computer using tomographic reconstruction algorithms to produce Tomography, tomographic (cross-sectional) images (virtual "slices") of a body. CT scans can be used in patients with metallic implants or pacemakers, for whom magnetic resonance imaging (MRI) is Contraindication, contraindicated. Since its development in the 1970s, CT scanning has proven to be a versatile imaging technique. While CT is most prominently used in medical diagnosis, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sestamibi Parathyroid Scintigraphy
Technetium (99mTc) sestamibi (INN; commonly sestamibi; USP: technetium Tc 99m sestamibi; trade name Cardiolite) is a pharmaceutical agent used in nuclear medicine imaging. The drug is a coordination complex consisting of the radioisotope technetium-99m bound to six (sesta=6) methoxyisobutylisonitrile (MIBI) ligands. The anion is not defined. The generic drug became available late September 2008. A scan of a patient using MIBI is commonly known as a "MIBI scan". Sestamibi is taken up by tissues with large numbers of mitochondria and negative plasma membrane potentials. Sestamibi is mainly used to image the myocardium (heart muscle). It is also used in the work-up of primary hyperparathyroidism to identify parathyroid adenomas, for radioguided surgery of the parathyroid and in the work-up of possible breast cancer. Cardiac imaging (MIBI scan) A ''MIBI scan'' or ''sestamibi scan'' is now a common method of cardiac imaging. Technetium (99mTc) sestamibi is a lipophilic cation w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
