Fun facts about brain Tumours

1. The mostcommon brain tumorsare cancers from other parts of the body (e.g. lung, breast, colon or prostate) that spreads to the brain.

2. Primary brain tumors originate in the brain and there are over 126 such tumors listed by WHO.

3.Glioma is the commonest primary brain tumour and originates from supporting brain cells that are called glial cells and 50% of all brain tumors begin as benign tumors.

4. Another brain tumour called ‘Astrocytomas’ are so named because their cells look like stars ; the word ‘astro’ in Latin means "star".

5. A primary brain tumour usually is restricted to brain and does not spread to other organs. If brain death occurs in these patients,it is possible to donate their organs.

6. In most instances the cause of brain tumor is not known and they do not discriminate among gender, class or ethnicity.

7. Each year approximately200,000 people in the United Statesare diagnosed with metastatic or primary brain tumor.

8. Commonsymptomsof a brain tumor include headaches, seizures, personality changes, eye weakness, nausea or vomiting, speech disturbances, memory loss.

9. The survival from brain tumor at five years is approximately 30%.

10. Brain tumors can be treated by surgery, radiation therapy, stereotactic   

radiotherapy, chemotherapy or by using these in combination. The most important issue when treating these patients, besides trying to cure them, is to ensure that the quality of life is not compromised.

1. Brain cancer is the leading cause of cancer deaths worldwide. Regrettably, the exact cause of brain cancer is unknown.
2. Brain cancer is popularly referred to as brain tumour. Brain tumours are cancerous cells from other parts of the body (e.g. lung, breast, stomach etc.) that spread to the brain.
3. WHO has listed around 126 primary brain cancers that develop in the brain. According to the American Brain Tumour Association, around 3,59,000 people in the US live with primary brain cancer.
4. Common symptoms of all forms of brain cancer include headaches, seizures, personality changes, eye weakness, nausea or vomiting, anxiety, speech disturbances, memory loss etc.
5. Males have higher risk of developing brain cancer than females, but glioma, the commonest primary brain cancer, occurs more in women than men.
6. Europeans have elevated chances of developing brain cancer compared with people of other ethnicities.
7. A primary brain cancer limits itself to brain and does not spread to other organs. A patient, who dies because of primary brain cancer, can possibly donate his or her organs.
8. Glioblastoma, meningioma and oligodendroglioma are different types of brain cancer that are often found in adults.  Oligodendroglioma have cells shaped like fried eggs. Another type of brain cancer called ‘Astrocytomas’ has cells that look like stars.
9. Metastatic brain cancer (that spreads from other parts of the body to the brain) is the most common type of brain cancer.
10. Brain cancer is not common among young people. Middle-aged people or people aged 65 have the risk of developing brain cancer.
11. Your cell phone emits radioactive waves, which is a potential cause of brain cancer.
12. According to the American Brain Tumour Association, all types of brain cancers are treatable, if caught early. There are around 130 types of brain cancer and therefore, are difficult to diagnose.
13. Standard treatment of brain cancer includes chemotherapy, radiation therapy and brain surgery.

Blood Fun Facts

Is blood thicker than water?  Blood is about twice as thick as water, thanks to all the cells and other bits that float in it. How long does it take a drop of blood to travel away from the heart and back again?  Roughly 20 to 60 seconds. Why are red blood cells shaped like breath-mint disks with a dent in the middle?  The breath-mint design allows cells to twist through capillaries, the tiniest blood vessels. A sphere or cube is less flexible and might get stuck. Also, the dents in the cells add to the surface area, allowing more oxygen and carbon dioxide to pass in and out of the cell. Why do mosquitos feed on blood?  Adult mosquitos actually eat the nectar of flowers. But mosquito babies need protein, not sugar, to grow. So their mothers feed on blood. Bloodsucking mosquito moms find you by sensing your body heat and breath. Then, with their proboscis, they drill a hole through your skin, into a capillary. Their saliva keeps the blood from clotting while they drink. Is all blood red?  No. Crabs have blue blood. Their blood contains copper instead of iron. Earthworms and leeches have green blood - the green comes from an iron substance called chlorocruorin. Many invertebrates, such as starfish, have clear or yellowish blood. How much blood is in your body?  Blood makes up about 10 percent of your body weight. Weigh yourself and divide your weight by 12 - that answer is about how many pints of blood your body has - adults usually have roughly 10 to 15 pints. A newborn baby has about one half pint or one cup of blood.

Could shark cartilage help cure cancer?

Sharks have been swimming in the Earth's oceans for about 400 million years. They predate humans, dinosaurs and just about anything that walks, crawls or swims. The average shark lives to be about 25, and it's believed that some sharks can live up to 100 years or more. This places them next to the whale as one of the longest-living sea creatures. The fact that they have such a long lifespan has prompted a great deal of research into the secret to their longevity.

Sharks have been studied closely for more than 100 years, mainly because of their low likelihood of contracting disease. Fish with bones have a pretty high rate of growing tumors. For a long time, scientists believed that sharks were immune to cancer and tumors. So what makes sharks different? They don't have bones. Their skeleton is made up entirely of cartilage. This is one reason that shark teeth are collectible -- it's the only fossil you can find from dead sharks. Their cartilage dissolves over time, and nothing is left but the hard-enameled teeth. Many researchers think that this cartilage holds the secret to the cure for some human medical conditions -- namely cancer.

The shark-cartilage industry is booming, to say the least -- some statistics place earnings at about $25 million per year [source:McGraw Hill]. Most of this money comes from the sale of over-the-counter supplements and vitamins containing shark cartilage. You can walk into any health supplement store or browse the Internet and find dozens of shark-cartilage products. It's typically sold in powdered form or packaged in an oral capsule. It's estimated that 100 million sharks are killed every year by humans. We can't know for sure how many are killed for their cartilage, but the vast amounts of shark products on the market give us a pretty good idea.

But could sharks really help cure disease? And can they aid in the fight against cancer? We'll get to the bottom of these questions on the following page

A fisherman cuts the fins off of a shark at the fish market in Abobodoume. The fins of the shark are dried and then exported to Asian countries, notably China and Japan.

Kambou Sia/Getty Images

Shark Cartilage

It was once believed that sharks didn't get cancer. Recent studies, including one conducted by Johns Hopkins University, have disproved those clai­ms. Hopkins professor Gary Ostrander and his research team found 40 cases of tumors in sharks and other elasmobranchs-- sea creatures with skeletons made of cartilage instead of bones. Proponents of using shark cartilage for human medication claim that it helps prevent something called angiogenisis. This is when a tumor continues to grow because of the formation of new blood vessels.

That sharks can and do get cancer makes it clear that ingesting their cartilage in a health-food supplement won't cure the disease in humans. To verify this, researchers have undertaken specific studies on the effects of shark cartilage in cancer patients. Studies on mice and on humans in 1998 and 2005 found that taking an oral shark-cartilage supplement had no effect on cancerous tumors. Results indicated that it didn't prevent the spread of cancer to other organs either. The study also found that taking the supplements led to some gastrointestinal side effects like diarrhea, nausea and vomiting. Shark cartilage also contains mercury, something doctors warn against because of its negative effects on the brain and kidneys.

But that hasn't stopped people from taking it. The media is quick to jump on a "miracle cancer cure" and did just that in 1993 when a "60 Minutes" episode featured a book that touted the use of the cartilage, titled "Sharks Don't Get Cancer." Professor Ostrander characterized the book's research as "overextensions" of some early experiments with shark cartilage.

Ostrander acknowledges that shark cartilage could help fight tumors if the key elements of the cartilage were isolated and administered to the tumor itself -- but a lot of research needs to take place first in order to determine any positive correlations. So while shark-cartilage supplements won't cure cancer, there may be some things we can learn by studying the predator.

Some of this research is already being performed at the Mote Marine Laboratory's Center for Shark Research in Sarasota, Fla., with the help of Clemson and South Florida Universities. Sharks have a tremendous resistance to disease, and much of the Mote laboratory research is centered on their immune system.

Most animals produce disease-fighting cells in their bone marrow. There's a delay from the time the disease appears to when the cells are produced and sent out to fight the disease. Since sharks have no bones, they produce immune cells mainly in their spleen and thymus. The Mote research indicates that because of this, the shark's immune cells are more readily available in the bloodstream and the lag time is eliminated. Their antibodies are also the smallest in the animal kingdom and are more able to penetrate tissue and get to the disease faster.

Although there may not be any evidence to suggest that ingesting shark products can have an effect on our own immune systems, we may be able to learn more about how immune cells behave by studying sharks.

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Is it harmful to breathe 100-percent oxygen?

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We breathe air that is 21 percent oxygen, and we require oxygen to live. So you might think that breathing 100 percent oxygen would be good for us -- but actually it can be harmful. So, the short answer is, pure oxygen is generally bad, and sometimes toxic. To understand why, you need to go into some detail …

Your lungs are basically a long series of tubes that branch out from your nose and mouth (from trachea to bronchi to bronchioles) and end in little thin-walled air sacs called alveoli. Think of soap bubbles on the end of a straw, and you'll understand alveoli. Surrounding each alveolus are small, thin-walled blood vessels, called pulmonary capillaries. Between the capillaries and the alveolus is a thin wall (about 0.5 microns thick) through which various gases (oxygen, carbon dioxide, and nitrogen) pass.

When you inhale, the alveoli fill with this air. Because the oxygen concentration is high in the alveoli and low in the blood entering the pulmonary capillaries, oxygen diffuses from the air into the blood. Likewise, because the concentration of carbon dioxide is higher in the blood that's entering the capillaries than it is in the alveolar air, carbon dioxide passes from the blood to the alveoli. The nitrogen concentration in the blood and the alveolar air is about the same. The gases exchange across the alveolar wall and the air inside the alveoli becomes depleted of oxygen and rich in carbon dioxide. When you exhale, you breathe out this carbon dioxide enriched, oxygen-poor air.

Just Breathe

Now what would happen if you breathed 100 percent oxygen? In guinea pigs exposed to 100 percent oxygen at normal air pressure for 48 hours, fluid accumulates in the lungs and the epithelial cells lining the alveoli. In addition, the pulmonary capillaries get damaged. A highly reactive form of the oxygen molecule, called the oxygen free radical, which destroys proteins and membranes in the epithelial cells, probably causes this damage. In humans breathing 100 percent oxygen at normal pressure, here's what happens:

• Fluid accumulates in the lungs.
• Gas flow across the alveoli slows down, meaning that the person has to breathe more to get enough oxygen.
• Chest pains occur during deep breathing.
• The total volume of exchangeable air in the lung decreases by 17 percent.
• Mucus plugs local areas of collapsed alveoli -- a condition called atelectasis. The oxygen trapped in the plugged alveoli gets absorbed into the blood, no gas is left to keep the plugged alveoli inflated, and they collapse. Mucus plugs are normal, but they are cleared by coughing. If alveoli become plugged while breathing air, the nitrogen trapped in the alveoli keeps them inflated.

The astronauts in the Gemini and Apollo programs breathed 100 percent oxygen at reduced pressure for up to two weeks with no problems. In contrast, when 100 percent oxygen is breathed under high pressure (more than four times that of atmospheric pressure), acute oxygen poisoning can occur with these symptoms:

• Nausea
• Dizziness
• Muscle twitches
• Blurred vision
• Seizures/convulsions

Such high oxygen pressures can be experienced by military SCUBA divers using rebreathing devices, divers being treated for the bends in hyperbaric chambers or patients being treated for acute carbon monoxide poisoning. These patients must be carefully monitored during treatment.

How the Antarctic Icefish Lost Its Red Blood Cells But Survived Anyway

In 1928, a biologist named Ditlef Rustad caught an unusual fish off the coast of Bouvet Island in the Antarctic. The “white crocodile fish,” as Rustad named it, had large eyes, a long toothed snout and diaphanous fins stretched across fans of slender quills. It was scaleless and eerily pale, as white as snow in some parts, nearly translucent in others. When Rustad cut the fish open, he discovered that its blood, too, was colorless—not a drop of red anywhere. The crocodile fish’s gills looked odd as well: they were soft and white, like vanilla yogurt; in contrast, a cod’s gills are as dark as wine, soaked in oxygenated blood.

Later, Johan Ruud and other researchers confirmed that the Antarctic icefishes, as they are now known, are the only vertebrates that lack both red blood cells and hemoglobin—the iron-rich protein such cells use to bind and ferry oxygen through the circulatory system from heart to lungs to tissues and back again. At first blush, biologists regarded icefishes’ pallor blood as a remarkable adaptation to the Antarctic’s freezing, oxygen-rich waters. Perhaps icefishes absorbed so much dissolved oxygen from the ocean through their gills and ultra thin skin that they could abandon those big, spongy red blood cells. After all, the biologists reasoned, thinner blood requires less effort to circulate around the body and saving energy is always an advantage, especially when you are trying to survive in an extreme environment.

More recently, however, some biologists have proposed that the loss of hemoglobin was not a beneficial adaptation, but rather a genetic accident with unfortunate consequences. Since icefish blood can only transport 10 percent as much oxygen as typical fish blood, icefishes were forced to dramatically alter their bodies in order to survive. In this scenario, despite an evolutionary blunder that would be lethal to most fish, the icefishes’ grit—as well as a little ecological serendipity—rescued them from their own bad blood. Scientists continue to revise icefishes’ evolutionary history as new evidence surfaces, but their story is surely one of the most unique and bizarre in the animal kingdom.

Icefishes live in the Southern Ocean, which encircles Antarctica. Rotating currents essentially isolate these waters from the world’s warmer seas, keeping temperatures low: temperatures near the Antarctic Peninsula, the northernmost part of the mainland, range from about 1.5 degrees Celsius in the summer to –1.8 degrees Celsius in the winter. Many fish in the Southern Ocean, including icefishes, produce antifreeze proteins to prevent ice crystals from forming in their blood when ocean temperatures drop below the freezing point of fresh water. Sixteen species of Antarctic icefishes comprise the family Channichthyidae, which falls under the larger suborder Notothenioidei. Among the hundreds of red-blooded Notothenioid species, only the icefishes lack hemoglobin. Together, the Notothenioids and icefishes dominate the waters they call home, accounting for approximately 35 percent of fish species and 90 percent of fish biomass in the Southern Ocean.

A Blackfin Icefish (Credit: Bill Baker)

By comparing icefish DNA to the DNA of red-blooded fish, William Detrich of Northeastern University and his colleagues identified the specific genetic mutations responsible for the loss of hemoglobin. Basically, one of the genes essential for the assembly of the hemoglobin protein is completely garbled in icefishes. Although no other animal completely lacks red blood cells, biologists have observed a diminishing of red blood cells in response to a changing environment. When it gets cold, it’s advantageous for fish to make their blood a little thinner and easier to circulate. Fish that live in cold waters usually have a smaller percentage of red blood cells in their blood than fish that live in warmer waters. And fish in temperate regionsdecrease the percentage of red blood cells in their blood each winter to save energy. Relying on these facts, some biologists assumed that Antarctic icefish evolved incredibly thin blood as an adaptation to the Southern Ocean.

Kristin O’Brien of the University of Alaska Fairbanks and her colleague Bruce Sidell (who is now sadly deceased) decided to test this assumption. In a paper titled “When bad things happen to good fish,” O’Brien and Sidell first point out that, compared to their cousins the Notothenioids and other similarly sized fish, icefishes have larger hearts and blood vessels. Although icefishes pump unusually thin blood through their bodies, their circulatory systems handle huge volumes. O’Brien and Sidell calculated that icefishes expend approximately twice as much energy as red-blooded Notothenioids moving all that extra blood. Whereas fish in temperate zones devote no more than five percent of their resting metabolic rate to their hearts, icefishes invest a whopping 22 percent of their body’s available energy in their giant tickers.* O’Brien and Sidell also show that icefish have more blood vessels nourishing certain organs than red-blooded fish. If you peel back the outer layers of a typical fish’s eye and fill the blood vessels with yellow silicone rubber, you will see a web of neatly segregated vessels tracing the contour of the eye like the ribs of a pumpkin. Do the same to an icefish’s eye and you will find a dense, tangled mess like a plate of spaghetti.

Like other biologists in recent years, O’Brien and Sidell view the icefishes’ large hearts and capillaries, high blood volume and dense nets of blood vessels as compensations for the loss of hemoglobin. But these adaptations alone might not have been enough to save icefishes from extinction—they likely benefited from fortuitous circumstances as well. Around 25 million years ago, the Southern Ocean flowing around Antarctica—which had broken away from other continents—began to cool. Not only did the colder water offer more oxygen, it also killed many species that did not evolve antifreeze proteins or otherwise adapt to the cold, creating a frigid sanctuary that the icefishes and their relatives have dominated ever since.

A crocodile icefish (Credit: Marrabbio2, Wikimedia Commons)

Today, however, icefishes face a new threat: manmade climate change. The Southern Ocean is getting warmer and possibly more acidic and less nutritious. O’Brien says researchers have shown that adult icefishes are more sensitive to changes in temperature than red-blooded fish—they cannot stand the heat. If Ruud was right—that “only in the cold water of the polar regions could a fish survive that has lost its pigment”—then the ongoing changes to the Southern Ocean might be the icefishes’ undoing. Consider this version of their story: icefishes evolved to survive sub-freezing temperatures in one of the most extreme environments on Earth, only to lose their red blood cells to a genetic accident; despite the mishap, they kept swimming, expanding their hearts and growing more blood vessels to get enough oxygen around their bodies; now, people are turning the Southern Ocean into a habitat for which icefishes are completely unsuited, forcing them to adapt once again or perish. Personally, I’m clinging to the hope that even if icefishes do not have any hemoglobin in their blood, they have plenty of resilience coursing through their veins.

*Source for cardiac energy investment: Hemmingsen, E. A. and Douglas, E. L. (1977). Respiratory and circulatory adaptations to the absence of hemoglobin in chaenichthyid fishes. In Adaptations within Antarctic Ecosystems (ed. G. A. Llano), pp. 479-487. Washington: Smithsonian Institution.

What is Blood?

        

         You know what blood is — it's that red stuff that oozes out if you get a paper cut. The average person has about 1 to 1½ gallons (4-6 liters) of it. But what is blood, really, and where does it come from?

How Does the Body Make Blood?

It's not made in a kitchen, but blood has ingredients, just like a recipe. To make blood, your body needs to mix:

• red blood cells, which carry oxygen throughout the body
• white blood cells, which fight infections
• platelets, which are cells that help you stop bleeding if you get a cut
• plasma, a yellowish liquid that carries nutrients, hormones, and proteins throughout the body

Your body doesn't go to the store to buy those ingredients. It makes them. Bone marrow — that goopy stuff inside your bones — makes the red blood cells, the white blood cells, and the platelets. Plasma is mostly water, which is absorbed from the intestines from what you drink and eat, with the liver supplying important proteins.

Put all these ingredients together and you have blood — an essential part of the circulatory system. Thanks to your heart (which pumps blood) and your blood vessels (which carry it), blood travels throughout your body from your head to your toes.

Let's find out more about each ingredient.

Red Blood Cells

Red blood cells (also called erythrocytes, say: ih-rith-ruh-sytes) look like flattened basketballs. Most of the cells in the blood are red blood cells. They carry around an important chemical called hemoglobin (say: hee-muh-glow-bin) that gives blood its red color.

Blood and breathing go hand in hand. How? The hemoglobin in blood delivers oxygen, which you get from the air you breathe, to all parts of your body. Without oxygen, your body couldn't keep working and stay alive.

White Blood Cells

White blood cells (also called leukocytes, say: loo-kuh-sytes) are bigger than red blood cells. There are usually not a whole lot of white blood cells floating around in your blood when you're healthy. Once you get sick, though, your body makes some more to protect you.

There are a couple types of white blood cells that do different things to keep you well:

Granulocytes

You know how your skin gets a little red and swollen around a cut or scrape? That means the granulocytes are doing their jobs. They have a lot to do with how your body cleans things up and helps wounds heal after an injury. Granulocytes also help prevent infection by surrounding and destroying things that aren't supposed to be in your body and by killing germs.

Lymphocytes

There are two types of lymphocytes: B cells and T cells. B cells help make special proteins called antibodies that recognize stuff that shouldn't be in your body, like bacteria or a virus you get from a sick friend. Antibodies are very specific, and can recognize only a certain type of germ. Once the antibody finds it, it gets rid of the germ so it can't hurt you.

The really cool part is that even after you are better, B cells can become memory cells that remember how to make the special antibody so that if the same germ infects you again, it can kill the germ even faster! T cells also battle germs that invade the body, but instead of making antibodies, they work by making special chemicals that help fight the infection.

Monocytes

Monocytes are white blood cells that fight infection by surrounding and destroying bacteria and viruses.

Platelets

Platelets, also called thrombocytes (say: throm-buh-sytes), are tiny round cells that help to make sure you don't bleed too much once you get a cut or scrape. Cuts and scrapes break blood vessels. If a platelet reaches a blood vessel that's been broken open, it sends out a chemical signal that makes other nearby platelets start to stick together inside the vessel.

After the platelets form this plug, they send out more chemical signals that attract clotting factors. These clotting factors work together to make a web of tiny protein threads. The platelets and this web of protein come together to make a blood clot. The clot keeps your blood inside the vessel while the break in the blood vessel heals up. Without platelets, you'd need more than a bandage to catch the blood when you scrape your knee!

Plasma

Plasma is a yellowish liquid that is mostly water. But it also carries important nutrients, hormones, and proteins throughout the body. Nutrients are chemicals from the food you eat that give your body energy and other things your body's cells need to do their work and keep you healthy.

Hormones carry messages throughout your body, telling it what to do and when. An example of a hormone is growth hormone. It gets your bones and muscles to grow. Many proteins in plasma are really important to your body, like the clotting factors that help you stop bleeding if you get a cut or a scrape.

Plasma also carries away cell waste — chemicals that the cell doesn't want anymore. Nutrients, hormones, proteins, and waste are dissolved in the plasma — kind of like the cocoa mix that dissolves in a cup of hot water. What are the marshmallows? The blood cells — they float in the plasma.

Hey, What's Your Type?

Everybody's blood is red, but it's not all the same. There are eight blood types, described using the letters A, B, and O. Those letters stand for certain proteins found on the red blood cells. Not everyone has the same proteins.

In addition to getting a letter or two, a person's blood is either "positive" or "negative." That doesn't mean one person's blood is good and another person's blood is bad. It's a way of keeping track of whether someone's blood has a certain protein called Rh protein. This protein is called "Rh" because scientists found it while studying Rhesus monkeys. If your blood is positive, you have this protein. If it's negative, you don't. Either way is totally fine.

People have one of these eight different blood types:

1. A negative
2. A positive
3. B negative
4. B positive
5. O negative
6. O positive
7. AB negative
8. AB positive

Blood types are important if a person ever wants to donate blood or needs a blood transfusion. Getting blood of the wrong type can make a person sick. That's why hospitals and blood banks are very careful with donated blood and make sure the person gets the right type.

People might need blood transfusions when they're sick or if they lose blood. Without enough healthy blood, the body won't get the oxygen and energy it needs. Healthy blood also protects you from germs and other invaders.

Now that you know how important blood is, what can you do? Kids generally aren't allowed to donate blood, but when you're older consider giving the gift of life!