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Ca2+ binds with the membrane of the synaptic vesicles, which causes the vesicles to break and release the neurotransmitter into the synaptic cleft. After the neurotransmitters are released, they diffuse across the synaptic cleft and interact with receptors on the postsynaptic membrane. When the action potential reaches the presynaptic terminal, it provokes the release of a small quantity of neurotransmitter molecules, which bind to chemical receptor molecules located in the membrane of another neuron, the postsynaptic neuron, on the opposite side of the synaptic cleft.
Portal hypertension is an increase in the blood pressure within a system of veins called the portal venous system. Veins coming from the stomach, intestine, spleen, and pancreas merge into the portal vein, which then branches into smaller vessels and travels through the liver.
Multicystic dysplastic kidney (MCDK) is a condition that results from the malformation of the kidney during fetal development. The kidney consists of irregular cysts of varying sizes. Multicystic dysplastic kidney is a common type of renal cystic disease, and it is a cause of an abdominal mass in infants.
Chronic obstructive pulmonary disease Email this page to a friend Print Facebook Twitter Google+ Chronic obstructive pulmonary disease (COPD) is a common lung disease. Having COPD makes it hard to breathe. There are two main forms of COPD: Chronic bronchitis, which involves a long-term cough with mucus Emphysema, which involves damage to the lungs over time Most people with COPD have a combination of both conditions. Causes Smoking is the main cause of COPD. The more a person smokes, the more likely that person will develop COPD. But some people smoke for years and never get COPD. In rare cases, nonsmokers who lack a protein called alpha-1 antitrypsin can develop emphysema. Emphysema Other risk factors for COPD are: Exposure to certain gases or fumes in the workplace Exposure to heavy amounts of secondhand smoke and pollution Frequent use of a cooking fire without proper ventilation Symptoms Symptoms may include any of the following: Cough, with or without mucous Fatigue Many respiratory infections Shortness of breath (dyspnea) that gets worse with mild activity Trouble catching one's breath Wheezing Because the symptoms develop slowly, some people may not know that they have COPD.
Marfan syndrome is a genetic disorder that affects the body’s connective tissue. Connective tissue holds all the body’s cells, organs and tissue together. It also plays an important role in helping the body grow and develop properly. marfan_general_2.jpg What is Marfan Syndrome?Connective tissue is made up of proteins. The protein that plays a role in Marfan syndrome is called fibrillin-1. Marfan syndrome is caused by a defect (or mutation) in the gene that tells the body how to make fibrillin-1. This mutation results in an increase in a protein called transforming growth factor beta, or TGF-β. The increase in TGF-β causes problems in connective tissues throughout the body, which in turn creates the features and medical problems associated with Marfan syndrome and some related disorders. Because connective tissue is found throughout the body, Marfan syndrome can affect many different parts of the body, as well. Features of the disorder are most often found in the heart, blood vessels, bones, joints, and eyes. Some Marfan features – for example, aortic enlargement (expansion of the main blood vessel that carries blood away from the heart to the rest of the body) – can be life-threatening. The lungs, skin and nervous system may also be affected. Marfan syndrome does not affect intelligence.
A bone marrow biopsy is part of a bone marrow test that takes a sample of your solid bone tissue. This test looks for abnormalities in your blood cells and signs of any diseases. You can request anesthesia or a sedative before the biopsy, and manage any pain afterward with over-the-counter medications.
In cases when the presentation is unclear, ultrasonography is the imaging methodology of choice. The characteristic finding is the presence of a "target sign". Ultrasonography is not required in patients with obvious clinical diagnosis (as seen in this patient). Such patients can proceed directly to treatment with diagnostic and therapeutic air (pneumatic) or water-soluble (hydrostatic contrast) enema.
Defibrillation is a treatment for life-threatening cardiac dysrhythmias, specifically ventricular fibrillation (VF) and non-perfusing ventricular tachycardia (VT). A defibrillator delivers a dose of electric current (often called a countershock) to the heart.
Pediatric orthopedic surgeons at Columbia are using a new device with magnetic technology that avoids the need for multiple spine-lengthening surgeries to correct early-onset scoliosis, a severe curvature of the spine in young children. In April 2014, Michael Vitale, MD, the Ana Lucia Professor of Pediatric Orthopedic Surgery at CUMC and 1995 graduate of P&S, performed the first procedure in the New York area, using the device to treat a 5-year-old boy. When braces and casts cannot control scoliosis in young children, surgeons turn to growing rods, which help correct the curve while allowing the spine to grow. When spinal maturity is near, the rods are removed and a spinal fusion can be performed. But during years of treatment with growing rods, patients must undergo surgery every six months to lengthen the rods to keep up with the patients’ growth. A patient may undergo eight to 10 procedures, which are costly and result in lost time for parents at work and children at school. The new device—MAGEC (MAGnetic Expansion Control) rods—contains a mechanism inside the growing rods that allows surgeons to lengthen the rods with a handheld external magnet, without surgery.