Case Study

Case 1

Three mice are used in the following experiment. Mouse 1 is put in the water basin where water is heated up to 30^oC. Five minutes later mouse 2 is put in the same basin. Ten seconds later both mice are taken out of the water and put in the pressure chamber. The third mouse (intact) is also put in the same chamber. The air is pumped out as in the experiment N 1 to bring the barometric pressure in the chamber down to 170-180 mm Hg. The intact mouse dies after 3-4 min of staying in the hypobaric conditions. Mouse 2 dies after 6-7 min, and the mouse 1 survives 15 min of hypoxia. At this point the experiment is stopped. When mouse 1 is taken out no signs of pathology are observed.

Questions:

What differences in resistance to hypoxia are seen in this experiment?

How can we explain the observed variations in sensitivity to hypobaric hypoxia?

Does hypothermia caused by evaporation of water from the surface of the body affect the resistance of mice 1 and 2 to hypobaric hypoxia? How can we name this factor in terms of pathophysiology?

Case 2

Three mice are used in the following experiment. Mouse N 1 is narcotized by a subcutaneous injection of morphine. This mouse is used in the experiment after it loses righting reflex indicating deep sleep. Mouse 2 is administered a central nervous system stimulator phenamine. Mouse 3 serves as control. All three mice are put in the pressure chamber, and the air is pumped out as in experiment N 1. Mouse 2 dies during the 1-2 min of its staying in the chamber, mouse 3 - during the 4th min; and mouse 3 survives 15 min in hypobaric conditions. At this point the last mouse is taken out of the chamber and examined after it has taken up. It shows no signs of pathology.

Questions:

What are differences in reactivity of mice toward hypobaric hypoxia in this test?

What are the possible mechanisms of these differences?

Case 3

1 year old child, 35 years men and 78 years men have lobar pneumonia. Will be the difference in current of the disease in these 3 cases?
Questions:

1. Determine the form of response in patients justify the answer
2. Define the concepts of reactivity and resistance of the body
3. Which types of reactivity can be seen in this experiment
4. Indicate the role of age in reactivity

Case 4

N., a healthy woman, whose father suffered from hemophilia A and mother was healthy, went to a genetic counseling unit. She was anxious about the risk of hemophilia to her grandsons. Her husband, as well as her son and two daughters were healthy.

Questions:

What is the pattern of inheritance of hemophilia A? What are the main features of this type of inheritance?