Scientific Method Beri Beri by pengxuebo

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									Scientific Method

   Elizabeth Baker
    1. Problem
State the problem or

 What is Beriberi?
  Woman with

The word beriberi
 is from a
 phrase meaning
 "I cannot, I
 cannot", the
 word being
 doubled for
                  Man with
Swollen joints,
  What Did Eijkman Know About
Eijkman had seen many victims of beriberi while
   working for the army in the Dutch East Indies.
   The disease started with signs of weakness,
   fatigue, irritability, restlessness, loss of appetite
   and vague abdominal discomfort. As it
   progressed, patients developed burning
   sensations, tingling in the extremities, and
   changes in the sensation such as numbness.
   Many of the sufferers died of heart failure.
   Autopsies showed that the nerve fibers and heart
   muscles had degenerated. In Asia beriberi had
   been a known disease for a few thousand years.
   Suddenly, after the 1870s, it became one of the
   most common diseases in the region.
Dutch East Indies
           2. Research
Research and gather information on
 the problem.

Dr. Eijkman gathered data about
 chickens with Beriberi and data on
 chickens without Beriberi.
           3. Hypothesis
Make an educated guess based on
 your research, then write it in an IF,
 THEN statement.

If healthy chickens were injected with
  bacteria from the blood of patients
  with Beriberi, then the chickens will
  contract Beriberi.
             4. Experiment
     conduct experiment, observe, &
              collect data

1.   They injected healthy chickens with
     bacteria from the blood of patients
     with Beriberi.
2.   They observed the patients that
     were injected.
3.   They recorded data from the
     patients that were injected.
            5. Conclusion
Was the hypothesis accepted or rejected,
 include date in your in your answer.

There hypothesis was rejected because the
  experimental group and the control group
  both contracted Beriberi.
   Eijkman's Trials; Monkeys,
    Chickens and Prisoners
During the first years of Eijkman's work at the institute in Java, two of his colleagues managed to
    extract micro-organisms from people who had died from beriberi. When they returned to Europe
    they left Eijkman behind as the institute's director.
Eijkman tried to infect rabbits and monkeys with the micro-organisms. However, the animals didn't
    get sick. Eijkman concluded that beriberi must be a disease which took a long time to develop.
    To wait a very long time, until the rabbits or monkeys showed signs of beriberi, wouldn't work.
    Chances that the animals got other diseases in the meantime were too great, and it would only
    be possible to draw conclusions if he had a very large number of animals to work on. He needed
    animals which developed the disease more quickly. It would also be good if they were cheap and
    easy to maintain.
Eijkman bought chickens and housed them in large cages in the shadow under the institute's
    extended roof. After less than a month, all chickens got sick. Eijkman thought that the chickens
    which he had injected with micro-organisms had infected the ones without injections. He bought
    new chickens and kept them, one by one, in smaller cages. But these chickens also got sick.
    Eijkman realized that the whole institute must be infected and decided to keep new chickens at
    another location. But as he did this, all the chickens got well. Eijkman couldn't understand what
    was happening. He hadn't done anything to cure them!
The man who fed the chickens told Eijkman that he had given them cooked white rice during the
    period they got sick. It was leftover rice from the next-door hospital. Later, a new cook there
    didn't want to give him left over rice and he had gone back to feeding them with unpolished
    uncooked rice. It was after this that the chickens had recovered.
When Eijkman understood that the disease had something to do with the diet, he decided to make
    trials. He did something like this... … Brown rice has its outer husk removed.
White rice is polished further to remove the thin skin and the germ. Since the germ is ground off
    from the white rice grains, they have a slightly pointed appearance.
After five weeks, it was clear to Eijkman that the diet did indeed cause the disease. He gave all the
    chickens unpolished uncooked rice, and the four sick chickens got well again.
Eijkman's Trials; Monkeys, Chickens and Prisoners
Eijkman repeated the experiment just to be sure and concluded that the
    important difference was that only one kind of rice had been cooked. It must
    therefore be that cooked rice helped an unknown microorganism to develop
    into a poison in the intestines of the chickens.
Or, perhaps, it was only cooked rice which had been stored for a few days that
    became poisonous in this way? He tested this, but no, even the chickens fed
    with freshly cooked rice became ill.
Or, could it be that the chickens couldn't absorb the nutrients from cooked rice?
Or, could it be that the water they had boiled the white rice in was toxic?
Trials showed that the answer to all these questions was "no." Neither was raw
    white rice less toxic than boiled. One thing that became clear was that, what
    mattered was if the rice had been polished or not. Only the chickens fed with
    polished rice developed the disease. If the chickens were fed polished rice,
    plus the skin which had been removed, they didn't get sick. For a change,
    Eijkman fed the chickens with raw meat, and the chickens stayed well.
    Eijkman's conclusion was that starch had some toxic effect on the chickens.
    He thought that the skin, which had been removed from the white rice,
    contained a substance that made the poisonous rice innocuous. Eijkman called
    this the anti-beriberi factor.
Eijkman described the trials in a report. He also wrote about them in Dutch
    scientific journals, so that other scientists could learn from them.
In 1895, after nine years of research with animals, Eijkman wanted to find out if
    humans could avoid getting beriberi by eating unpolished rice. He asked a
    doctor named A. G. Vorderman to carry out investigations in the prisons. The
    reason why he decided to do this in the prisons was that it was easy to control
    what people ate, and that the same persons stayed there for a long time. It
    soon showed that prisoners who were fed polished rice were a lot more likely
    to get beriberi.
Before the trials in the prisons were completed, Eijkman returned to the
    Netherlands. Vorderman and other physicians continued their research.
        6. Communication
Share and communicate your ideas
 with others.

Dr. Eijkman can sell his ideas to
 science institutes.
Christiaan Eijkman (August 11, 1858,
   Nijkerk – November 5, 1930,
   Utrecht) was a Dutch physician and
   pathologist whose demonstration
   that beriberi is caused by poor diet
   led to the discovery of vitamins.
   Together with Sir Frederick Hopkins,
   he received the Nobel Prize for
   Physiology or Medicine.
Although Eijkman had been sent to
   Indonesia to study Beriberi, the
   discovery of the cause was
   accidental. He noticed the symptoms
   in some chickens used in his
   laboratory when their feed had been
   altered temporarily. Eijkman was
   unable to continue his research due
   to ill health, but a study by his friend
   Adolphe Vorderman confirmed the
   link between polished rice and the
   disease. Eventually it was
   determined the missing compound
   that was causing Beriberi was
   vitamin B1, thiamine.
         Why Was Beriberi Such a
           Common Disease?
   People found the polished rice from the new milling machines
    superior in taste, and they chose it over brown rice even if it was
    more expensive.
   It was in the 1870s that thiamin deficiency became a common
    disease in many parts of Southeast Asia. In some towns, as many
    as half of the babies died from it. Europeans had taken steam
    driven mills to Asia, and the new rice-processing machines
    completely polished the grains. This rice was considered to be of
    superior taste and quality, and was eaten by most people in Asia.
    But, since the polishing had been removed, so had the B1
    vitamins. For people who ate mostly rice, beriberi was a sure fate.
   Today, beriberi is no longer a common disease. Since the 1940s,
    food items such as rice, white flour, pasta and cereals are often
    enriched with Vitamin B1. The practice of eating varied foods and
    the enrichment of processed foods with vitamins, have helped
    save the lives of millions.
Even if people hadn't heard of vitamins before
  the 20th century, many understood that it
  was important to eat varied food. And most
  people did. Problems with malnutrition
  usually occurred when people were on long
  journeys at sea, working for the army or
  imprisoned. In Japan a doctor in the navy,
  Takaki, understood that beriberi could be
  avoided if the men ate less rice and more
  vegetables, barley, fish and meat. When he
  showed how successful this method was, it
  was made into a naval regulation in Japan.
  Eijkman had probably not heard about this,
  even if it happened at the same time as he
  was on his way to Java.
   In Asia where polished white rice was the common staple food of
    the middle class, beriberi resulting from lack of vitamin B was
    endemic. In 1884, Takaki Kanehiro, a British-trained Japanese
    medical doctor of the Japanese Navy observed that beriberi was
    endemic among low ranking crew who often ate nothing but rice
    but not among crews of Western navies and officers who were
    entitled to a Western-style diet. Kanehiro initially believed that
    lack of protein was the chief cause of beriberi. With the support
    of Japanese navy, he experimented using crews of two
    battleships, one crew was fed only white rice, while the other
    was fed a diet of meat, fish, barley, rice, and beans. The group
    that ate only white rice documented 161 crew with beriberi and
    25 deaths, while the latter group had only 14 cases of beriberi
    and no deaths. This convinced Kanehiro and the Japanese Navy
    that diet was the cause of beriberi. This was confirmed in 1897,
    when Christiaan Eijkman discovered that feeding unpolished rice
    instead of the polished variety to chickens helped to prevent
    beriberi in the chickens. The following year, Frederick Hopkins
    postulated that some foods contained "accessory factors"—in
    addition to proteins, carbohydrates, fats, etcetera—that were
    necessary for the functions of the human body.[2]
   Christiaan Eijkman, a Dutch physician and pathologist,
    demonstrated that beriberi is caused by poor diet. His work led
    to the discovery of vitamins. Together with Sir Frederick
    Hopkins, he was awarded the 1929 Nobel Prize for Physiology or
    Medicine for the discovery.
           The 1929 Nobel Prize in
           Physiology or Medicine
   Christiaan Eijkman was awarded the Nobel Prize in Physiology or
    Medicine in 1929. Due to bad health, he couldn't come to Sweden
    to receive the Prize. He died a year later.
   In 1929, Eijkman shared the Nobel Prize in Physiology or Medicine
    with Frederick Hopkins.
   One may wonder why Eijkman was awarded the Prize for the
    discovery of vitamin B1 even if he himself didn't discover it.
   Eijkman was actually awarded the Prize because he was the first
    to point out a substance in the rice skin - a substance not to be
    known as the anti-beriberi factor as Eijkman called it, but what
    later was to be known as vitamin B1. He was also awarded the
    Prize for his new way of investigating and his methods to control
    diseases caused by vitamin deficiency. His trials had become
    famous, and in the late 1920s it was obvious that his work had
    spurred developments in nutrition research.
                         Vitamin B1                              Funk

   Because it is water soluble, B1 is not stored in the body and must be
    supplied daily. Chickpeas, beans, lentils, brown rice, lean pork and peas
    are all good sources of vitamin B1.
   In the 1800s, it was known that people needed proteins, carbohydrates,
    fat and salt to stay healthy. No one had heard of vitamins.
   One of the first to find out that food contains other things that people
    need was Gerrit Grinjs, who now took Eijkman's place at the institute and
    did more research. He understood that white rice wasn't toxic, but that it
    lacked something vital.
   In 1906, the British biochemist Frederick Hopkins demonstrated that food
    contains necessary "accessory factors" in addition to proteins,
    carbohydrates, fats, salts and water.
   In 1912, the chemist Casimir Funk thought that he had found the vital
    substance Eijkman called the anti-beriberi factor. Funk gave it the name
    Vitamine. (He coined the word by combining "vital" and "amine.") This
    name later came to denote all vitamins, even if the "e" soon was dropped.
   However, Funk hadn't found the right substance. Not until 1926 was the
    vitamin, which was to be named Thiamin or B1, isolated in its pure form.
    Its structure was fully elucidated and the vitamin synthesized in 1936.
    World's Healthiest Foods ranked as quality sources of:
                           Vitamin B1 (thiamin) Foods Rating

Romaine lettuce 2 cup very good              Turnip greens, cooked 1 cup good
Asparagus, boiled1 cup very good             Broccoli, steamed1 cup good
Crimini mushrooms, raw5 oz-very              Green beans, boiled1 cup good
   good                                      Corn, yellow, cooked1 cup good
Spinach, boiled1 cup4 very good
                                             Kale, boiled1 cup good
Sunflower seeds, raw0.25 cup very
   good                                      Black beans, cooked1 cup good
Tuna, yellowfin, baked/broiled4 oz-          Pineapple 1 cup good
   very good                                 Oats, whole grain, cooked 1 cup
Celery, raw1 cup good                           good
Green peas, boiled1 cup very good            Oranges 1 each good
Tomato, ripe1 cup very good                  Cauliflower, boiled1 cup good
Eggplant, cooked, cubes1 cup2 very
   good                                      Swiss chard, boiled1 cup good
Mustard greens, boiled1 cup good             Collard greens, boiled 1 cup good
Brussel sprouts, boiled1 cup very good       Split peas, cooked1 cup good
Cabbage, shredded, boiled1 cup good          Lentils, cooked1 cup good
Watermelon, diced1 cup good                  Navy beans, cooked1 cup good
Bell peppers, red, raw, slices 1 cup         Garlic 1 oz-wt good
Carrots, raw1 cup good                       Lima beans, cooked 1 cup good
Summer squash, cooked, slices 1 cup          Pinto beans, cooked1 cup good
   good                                      Sesame seeds 0.25 cup good
Winter squash, baked, cubes1 cup             Grapes 1 cup good
                                             Kidney beans, cooked 1 cup good

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