What factors affect the mouse in this experiment?

Which of these factors could be considered the leading cause of the pathologic process - hypobaric hypoxia?

How can you experimentally check your presumptions about the nature of the pathologic process?

Case 4

Air is pumped out of the pressure chamber to bring the barometric pressure to approximately 20-30 mmHg. Then the chamber is filled with pure O₂ up to normal atmospheric pressure 750 mm Hg. A mouse is carefully put in the chamber so that the barometric pressure inside remains unchanged. The mouse is then observed as in the previous experiment. At first, seeking behavior is seen. Later the mouse is sitting quietly, showing no signs of pathology. Within approximately 10 minutes after the start of the experiment the mouse is taken out of the chamber, and its normal behavior and state is established. Questions:

1. Taking into account the results of this test what can you say about the pathologic factors which caused death of the mouse in the previous experiment?

Case 5

A pressure chamber is filled with a mixture of gases consisting of 95% N₂ and of 5% O₂. Barometric pressure inside the chamber is maintained equal to normal atmospheric pressure. A mouse is put in the chamber. A thin jet of the same gas mixture is being passed through the chamber. Partial pressure of O₂ in this gas mixture is about 37 mm Hg. After staying in the chamber for 10-15 min the mouse develops seizures and then dies.

Considering the results of all 3 experiments, answer the following questions:

Which factor caused the development of acute hypobaric hypoxia and death of the mouse?

What is the significance of hypobaria itself, that is, decreased pressure of the inhaled air?

 

Hand-outs: lecture, multimedia presentation, cases

THE LIST OF LITERATURE:

The basic

7. Litvitsky P.F., Pirozhkov S.V., Tezikov E.B. Concise lectures and tests on pathophysiology E-tekstbook. – ГЭОТАР-Медиа, 2007

8. Lectures, handouts.

9. Pathologic basis of disease. Environmental and nutritional pathology. V. Kumar, A.K. Abbas, S.N. Fausto, 8th edition, 2010, P.415-446

10. Basic Pathology. Vinay Kumar, Ramsi S. Cotran, Stanley L. Robbins. 9^th edition, 2013.- P 221-243.

Additional

11. Textbook of medical physiology. High altitude and space physiology. A.C. Guyton, J.E. Hall., 9^th edition, 1996.-P 549-562.

12. Textbook of pathology. Harsh Mohan 4rd edition, Delhi, 12004, P 3-13.

Control –conclusions on case study

 

3. THEME:

«THE ROLE OF REACTIVITY OF AN ORGANISM IN PATHOLOGY»

The purposes of the class:

· Formation of knowledge of the main issues of the theme

· Formation of skills to use the knowledge of the theoretical material for pathogenetic schemes and pathophysiological analysis of clinical cases

· Formation of communicative skills for discussion of the problem

Tasks of study:
• To learn the main issues of the theme
• To develop the skills to use the glossary in three languages for discussion of the theoretical material
• To Learn how to make pathogenetic schemes, to allocate the leading link and  vicious circles
• To apply the theoretical knowledge in solving of clinical cases

• To form communicative skills for discussion of the theoretical material

 Questions for the theme

1. Reactivity and resistance of an organism, definition.

2. Forms of organism response to pathogenic factor.

3. Types of reactivity and their characteristic. The factors determining reactivity (heredity, constitution, age, sex, function of nervous, endocrine systems, etc.).

4. Constitution of organism, definition. Classification of constitutional types on Sigout, Krechmer E., Pavlov I.P., Chernorutsky M.V., Bogomolez A.A. The role of organism’s constitution in reactivity.

5. The role of age in reactivity. Features of reactivity of children's and senile age.

6. The role of sex in reactivity. Features of reactivity of male and female organism.

Methods of teaching

Discussion the major issues under the supervision of a teacher, discussion of video film “The Role of age, function of CNS, species reactivity in resistance to hypoxy”.

Methods of control

Oral questioning, checking conclusions on experiment, testing