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Sleep apnea is a potentially serious sleep disorder in which breathing repeatedly stops and starts. You may have sleep apnea if you snore loudly, and you feel tired even after a full night's sleep. The main types of sleep apnea are: Obstructive sleep apnea, the more common form that occurs when throat muscles relax. Central sleep apnea, which occurs when your brain doesn't send proper signals to the muscles that control breathing. Complex sleep apnea syndrome, also known as treatment-emergent central sleep apnea, occurs when someone has both obstructive sleep apnea and central sleep apnea. If you think you might have any form of sleep apnea, see your doctor. Treatment can ease your symptoms and may help prevent heart problems and other complications.
Angina is a term used for chest pain caused by reduced blood flow to the heart muscle. Angina (an-JIE-nuh or AN-juh-nuh) is a symptom of coronary artery disease. Angina is typically described as squeezing, pressure, heaviness, tightness or pain in your chest. Angina, also called angina pectoris, can be a recurring problem or a sudden, acute health concern. Angina is relatively common but can be hard to distinguish from other types of chest pain, such as the pain or discomfort of indigestion. If you have unexplained chest pain, seek medical attention right away.
Initial symptoms may include: Pain or discomfort in the upper tummy (abdomen), especially after eating. Indigestion. (Note: most people who have indigestion do not have stomach cancer.) Feeling sick, and being off food. ... Weight loss and/or loss of appetite. You may pass blood out with your stools (faeces).
What are the symptoms of spinal meningitis in adults? Causes. The most common cause of viral meningitis is. ... Symptoms. Viral meningitis usually begins with symptoms of a viral infection, such as fever, a general feeling of illness (malaise), cough, muscle aches, vomiting, loss of appetite, and headache. ... Diagnosis. ... Treatment. ... Prognosis.
Absence of a woman's monthly menstrual period is called amenorrhea. Secondary amenorrhea is when a woman who has been having normal menstrual cycles stops getting her periods for 6 months or longer. Causes Secondary amenorrhea can occur due to natural changes in the body. For example, the most common cause of secondary amenorrhea is pregnancy. Breastfeeding and menopause are also common, but natural, causes. Women who take birth control pills or who receive hormone shots such as Depo-Provera may not have any monthly bleeding. When they stop taking these hormones, their periods may not return for more than 6 months. You are more likely to have absent periods if you: Are obese Exercise too much and for long periods of time Have very low body fat (less than 15 to 17%) Have severe anxiety or emotional distress Lose a lot of weight suddenly (for example, from strict or extreme diets or after gastric bypass surgery) Other causes include: Brain (pituitary) tumors Drugs for cancer treatment Drugs to treat schizophrenia or psychosis Overactive thyroid gland Polycystic ovarian syndrome Reduced function of the ovaries
Spina bifida is a condition that affects the spine and is usually apparent at birth. It is a type of neural tube defect (NTD). Spina bifida can happen anywhere along the spine if the neural tube does not close all the way. When the neural tube doesn’t close all the way, the backbone that protects the spinal cord doesn’t form and close as it should. This often results in damage to the spinal cord and nerves. Spina bifida might cause physical and intellectual disabilities that range from mild to severe. The severity depends on: The size and location of the opening in the spine. Whether part of the spinal cord and nerves are affected.
Insert the needle into the rubber stopper of the insulin bottle. Push the plunger down to inject air into the bottle (this allows the insulin to be drawn more easily). Leave the needle in the bottle. Turn the bottle and syringe upside-down.
The complex circuitry interconnecting different areas in the brain, known collectively as white matter, is composed of millions of axons organized into fascicles and bundles. Upon macroscopic examination of sections of the brain, it is difficult to discern the orientation of the fibers. The same is true for conventional imaging modalities. However, recent advancements in magnetic resonance imaging (MRI) make such task possible in a live subject. By sensitizing an otherwise typical MRI sequence to the diffusion of water molecules it is possible to measure their diffusion coefficient in a given direction1. Normally, the axonal membrane and myelin sheaths pose barriers to the movement of water molecules and, thus, they diffuse preferentially along the axon2. Therefore, the direction of white matter bundles can be elucidated by determining the principal diffusivity of water. The three-dimensional representation of the diffusion coefficient can be given by a tensor and its mathematical decomposition provides the direction of the tracts3; this MRI technique is known as diffusion tensor imaging (DTI). By connecting the information acquired with DTI, three-dimensional depictions of white matter fascicles are obtained4. The virtual dissection of white matter bundles is rapidly becoming a valuable tool in clinical research.
Our journey begins with a transverse section of tightly packed axons as seen through light microscopy. Although represented as a two-dimensional "slice", we see that these axons in fact resemble tubes. A simulation of water molecules diffusing randomly inside the axons demonstrates how the membranes and myelin hinder their movement across them and shows the preferred diffusion direction --along the axons. The tracts depicted through DTI slowly blend in and we ride along with them. As we zoom out even more, we realize that it is a portion of the corpus callosum connecting the two sides of the brain we were traveling on and the great difference in relative scale of the individual axons becomes evident. The surface of the brain is then shown, as well as the rest of the white matter bundles--a big, apparently chaotic tangle of wires. Finally, the skin covers the brain.
With the exception of the simulated water molecules, all the data presented in the animation is obtained through microscopy and MRI. Computer algorithms for the extraction of the cerebral structures and a custom-built graphics engine make our journey through the brain's anatomy possible in a living person.
Micrograph courtesy of Dr. Christian Beaulieu, University of Alberta.
Music by Mario Mattioli.
References:
1. Stejskal, E.O., et al., J. Chem. Phys., 1965. 42:
2. Beaulieu, C., NMR Biomed., 2002. 15:435-55.
3. Basser, P.J., et al., J. Magn. Reson. B, 1994. 103:247-54.
4. Mori, S., et al., NMR Biomed., 2002. 15:468-80.
The condition is caused by a blockage in the lymphatic system, part of the immune and circulatory systems. Lymphedema is most commonly caused by lymph node removal or damage due to cancer treatment. The main symptom is swelling in an arm or leg that may be accompanied by pain or discomfort. Exercise, wrapping, massage, and compression can help.