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Human Physiology
Homework: GI system
Problem 1. Describe the mechanism of amino acids absorption in the small intestine. Repeat for
all nutrients.
Problem 2. Does GI tract regulate water absorption?
Does GI tract regulate water absorption?
Does GI tract regulate water content of the blood?
Does GI tract regulate Na+ absorption?
Does GI tract regulate Na+ concentration in the blood?
Does GI tract regulate glucose absorption?
Does GI tract regulate glucose concentration in the blood?
Does GI tract regulate amino acids absorption?
Does GI tract regulate amino acids concentration in the blood?
Does GI tract regulate cholesterol absorption?
Does GI tract regulate cholesterol concentration in the blood?
Problem 3. Describe the fate of lactose in a lactose intolerant person person with no lactase function. Lactose (shown on the right) is
normally split by lactase.
Human Physiology
Homework: GI system
Problem 4. Please read the following case report. Formulate the cause of patient’s death using
your own words – what was the main cause of death?
How would you change patient’s care to prevent such cases in the future?
Gangrene Caused Death of Healthy Liver Donor
SourceURL:http://www.reutershealth.com
NEW YORK (Reuters Health) - Over two years ago, the case of a man who died at Mount Sinai
Hospital in New York after donating a portion of his liver to his brother gained a lot of media
attention. According to a report published this month, fulminant gas gangrene of the stomach
was the cause of death.
The healthy 57-year-old man volunteered to give the right section of his liver to his brother in
January 2002. The operation and the man's recovery were uneventful until the evening of
second day after surgery, when he developed nausea and hiccups.
Early the next day, he seemed well and sat in a chair. Within a few hours, however, he
developed a rapidly racing heart, plummeting blood pressure, and vomiting of blood.
Despite efforts to resuscitate him, the patient died.
"Autopsy demonstrated gas gangrene of the stomach as the underlying cause of the
hemorrhage and numerous colonies of Gram-positive bacilli were identified," the team that
cared for the patient reports in the medical journal Liver Transplantation.
Gas gangrene occurs when severe bacterial infection produces gas from fermentation that
permeates surrounding tissue, causes widespread tissue damage, and leads to toxic shock.
The lead author of the report, Dr. Charles M. Miller, is now chief of liver transplantation at the
Cleveland Clinic Foundation in Ohio.
Miller and his colleagues report that, on the first day after surgery, the patient was feeling so
well that he asked his family to bring him takeout food from a local restaurant. The team
speculates that "it is most likely that infection resulted from bacteria in the lobster dinner" from
the restaurant, based on the type of bacteria identified.
The man's stomach may have been unable to ward off massive infection because of the surgical
stress, a drop in blood supply to the stomach because of the diminished liver size [AV: surgeon
could have stop blood flow through one of the gastric arteries in order to access the liver] , and
the fact that he had been given gastric-acid suppressing drugs, the clinicians suggest. Stomach
acid usually kills bacteria.
...
SOURCE: Liver Transplantation, October 2004.
Human Physiology
Homework: GI system
Problem 5. LAS VEGAS, Nevada -- A mother accused of killer her daughter by withholding her
insulin, sat on a couch watching TV with a beer in front of her as her daughter lay sick in bed,
the girl's best friend testified Thursday.
By Chris O'Connell / Court TV
Friday, October 21, 2005; Posted: 1:59 p.m. EDT (17:59 GMT)
Cheryl Botzet is accused of murdering her diabetic
daughter by withholding her insulin.
The next day, the girl went to the hospital, where she
died. Her mother, Cheryl Botzet, is on trial, charged with
first-degree murder.
Twelve-year-old Nicole Peron testified that she could
immediately tell that her friend, Ariel Botzet, was not
well when she arrived at the family's apartment that day.
"She was feeling sick," Peron said. "She looked pale. She looked like she wasn't her normal self."
However, the young witness stopped short of saying she had actually seem Ariel vomit, as
prosecutors had previously promised jurors she would. She also couldn't say that Ariel's mother,
Cheryl Botzet, had actually been drinking the beer.
"I saw her on the couch. There was beer on the table, but I didn't see her drink it," Nicole
testified.
On February 6, 2004, Ariel Botzet suffered a cerebral edema due to diabetic keto-acidosis, or
DKA, a condition caused by insulin deficiency.
She lost consciousness as paramedics carried her into a Las Vegas hospital, and then died after
spending several days in intensive care.
If convicted, Botzet, 39, faces a possible sentence of life in prison.
…
Dr. Richard Sterett, the emergency room doctor who cared for Ariel after she lost consciousness,
confirmed that he heard from another doctor that Ariel had repeatedly vomited in the few days
before she was admitted to the hospital.
When Sterett first treated her after she lost consciousness, Ariel's right pupil was severely
dilated. He also explained for jurors the symptoms of a cerebral edema.
"It's basically saying that the brain is swelling. As the brain swells, it basically smashes itself,"
Sterett said.
On cross-examination, however, Sterett conceded that there are numerous causes for cerebral
edemas in diabetics other than DKA, such as the rapid infusion of liquids into a patient.
Human Physiology
Homework: GI system
Diabetic ketoacidosis
Diabetic ketoacidosis (DKA) is a life-threatening complication in patients with untreated
diabetes mellitus (chronic high blood sugar or hyperglycemia). Near complete deficiency of
insulin and elevated levels of certain stress hormones combine to cause DKA. DKA was a major
cause of death in Type I diabetics before insulin injections were available; untreated DKA has a
high mortality rate.
Ketone body production
Despite possibly high circulating levels of plasma glucose, the liver will act as though the body is
starving if insulin levels are low. In starvation situations, the liver produces another form of fuel:
ketone bodies. Ketogenesis, that is fat metabolic processing (beginning with lipolysis), makes
ketone bodies as intermediate products in the metabolic sequence as fatty acids (formerly
attached to a glycerol backbone in triglycerides) are processed. The positive charge of ketone
bodies causes decreased blood pH.
Brain
Normally, ketone bodies are produced in minuscule quantities, feeding only part of the energy
needs of the heart and brain. In DKA, the body enters a starving state. Eventually, neurons (and
so the brain) switch from using glucose as a primary fuel source to using ketone bodies.
As a result, the bloodstream is filled with an increasing amount of glucose that it cannot use
(as the liver continues gluconeogenesis and exporting the glucose so made). This significantly
increases its osmolality. At the same time, massive amounts of ketone bodies are produced,
which, in addition to increasing the osmolar load of the blood, are acidic. As a result, the pH of
the blood begins to move downward towards an acidotic state. The normal pH of human blood
is 7.35-7.45, in acidosis the pH dips below 7.35. Very severe acidosis may be as low as 6.9-7.1.
The acidic shift in the blood is significant because the proteins (i.e. body tissues, enzymes, etc.)
in the body can be permanently denatured by a pH that is either too high or too low, thereby
leading to widespread tissue damage and functional deficits, organ failure, and eventually
death.
As glucose is excreted in the urine, it takes a great deal of body water with it, resulting in
dehydration. Dehydration further concentrates the blood and worsens the increased osmolality
of the blood. Severe dehydration forces water out of cells and into the bloodstream to keep vital
organs perfused. This shift of intracellular water into the bloodstream occurs at a cost as the
cells themselves need the water to complete chemical reactions that allow the cells to function.
Human Physiology
Homework: GI system
Problem 6. Babies left fighting for their lives after getting botulism 'from eating honey'
http://www.dailymail.co.uk/news/article-2546017/Babies-left-fighting-lives-getting-botulismeating-honey.html
Two British babies have contracted a rare life-threatening disease triggered by eating honey.
The boys, aged three months and five months, had to be put on life-support machines suffering
from infant botulism.
Both had been feeding badly and showed typical symptoms – a floppy head, drooping eyelids
and constipation. ... The younger boy had eaten honey, while the older one had been given a
homeopathic treatment that may have contained honey, which can carry the potentially deadly
bacteria. The identities of the babies treated and the hospitals involved have not been disclosed.
But according to the latest health protection report from Public Health England, the five-month-old
was diagnosed just before Christmas in central or southern England.
He may still be in hospital because recovery can sometimes take six months. He had taken the
homeopathic remedy before becoming ill, though tests on it showed no trace of botulism.
The three-month-old was treated at a children’s hospital in northern England and has recovered.
His mother admitted giving him honey at home, though tests on what was left in the jar also failed
to detect the botulism bacteria.
Questions: Why you should not give honey to kids younger than 1 year old?
What are the effects of botulinum toxin?