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This video: Multiple myeloma is a cancer that forms in a type of white blood cell called a plasma cell. Plasma cells help you fight infections by making antibodies that recognize and attack germs. Multiple myeloma causes cancer cells to accumulate in the bone marrow, where they crowd out healthy blood cells. Rather than produce helpful antibodies, the cancer cells produce abnormal proteins that can cause kidney problems. Treatment for multiple myeloma isn't always necessary. If you're not experiencing signs and symptoms, you may not require treatment. If signs and symptoms develop, a number of treatments can help control your multiple myeloma.
Uterine rupture is usually when the scar from your previous caesarean section tears open. Though it's uncommon, you should be aware of this risk, particularly if you're thinking about giving birth vaginally next time. It's possible for your scar to gape slightly while you're pregnant (scar dehiscence).
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.
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.
Menorrhagia is the medical term for menstrual periods with abnormally heavy or prolonged bleeding. Although heavy menstrual bleeding is a common concern, most women don't experience blood loss severe enough to be defined as menorrhagia. With menorrhagia, you can't maintain your usual activities when you have your period because you have so much blood loss and cramping. If you dread your period because you have such heavy menstrual bleeding, talk with your doctor. There are many effective treatments for menorrhagia. Symptoms Signs and symptoms of menorrhagia may include: Soaking through one or more sanitary pads or tampons every hour for several consecutive hours Needing to use double sanitary protection to control your menstrual flow Needing to wake up to change sanitary protection during the night Bleeding for longer than a week Passing blood clots larger than a quarter Restricting daily activities due to heavy menstrual flow Symptoms of anemia, such as tiredness, fatigue or shortness of breath
Pelvic ureter. The ureter enters the pelvis, where it crosses anteriorly to the iliac vessels, which usually occurs at the bifurcation of the common iliac artery into the internal and external iliac arteries. Here, the ureters are within 5 cm of one another before they diverge laterally.
An epidural abscess is a collection of pus (infected material) between the outer covering of the brain and spinal cord and the bones of the skull or spine. The abscess causes swelling in the area. Spinal cord abscess (SCA) is a rare condition capable of causing permanent damage to the spinal cord. Abscesses are caused when injured tissue becomes infected. The body's immune system sends white blood cells to help fight off the infection. They begin to fill the damaged tissue, causing pus to build up.
We are aware that the "official" way to use an ear candle is small end down into the ear, but for this video, we have elected to use it the way most "lay" public would (small end up). Ear candling is an alternative medicine practice that is thought to remove earwax. However, this video illustrates how ineffective this practice is in removing earwax... and can potentially be even harmful. And yes... It is still frequently practiced.