- Horner's syndrome.

Horner's syndrome

*Def:-

It is a clinical syndrome caused by damage to the sympathetic nerve supply to head and neck.

*synonymes:-

• Bernard-Horner syndrome
• oculosympathetic palsy.

*Causes:-

Due to lesion or compression of one side of the cervical or thoracic sympathetic chain which generates symptoms on the ipsilateral (same side as lesion) side of the body:-

- Organization of human body.

1- Human body (total organism) is complicated &

highly organized & composed of number of systems:-

-Musculoskeletal system.
-Respiratory system.
-Cardiovascular system.
-Hemic and lymphatic systems including immune system.
-Gastrointestinal system.
-Urogentital system.
-Endocrine system.
-Nervous system.
-Integumentary system:- skin, hair and nails.


2- One system is composed of group of organs which

together perform the over all function of the system.(1)

3- An organ :- is composed of several different tissues

which together perform the particular function of the organ.


4- A Tissue :- is a group of cells working together &

these cells are separated by inter-cellular substance.

e.g Muscular tissue & neural tissue.(1)


5- Cell :- is the smallest living unit of the body construction (2)&

it is the structural & functional unit in the body.

cell is composed of complex structure called protoplasm.(2)

In eukaryotes the protoplasm surrounding the cell nucleus

is known as the cytoplasm and

that inside the nucleus as the nucleoplasm.(3)


6- Protoplasm is composed of a mixture of different molecules :-

- water 70%

- proteins 15%

- nucleic acids 1%

- polysaccharides 3%

- lipids 1%

- Minerals & others 4%


7- Molecules are formed of elements :-

- carbon (C)

- hydrogen (H)

- oxygen (o)

- Nitrogen (N)

- phosphorus (p)

- sulfur (s)


Elements are substances which cannot be broken down further

by ordinary chemical means


*References:-

(1) Introduction to anatomy ,Anatomy & embryology department,
Mansoura uni 2006.
(2) Principles of histology vol 1 , Ch 2 cytoplasm,
histology staff members , Mansoura uni 2006.
(3) wikipedia here
(4) Medical biochemistry, Vol 1,Physical chemistry,
Medical biochemistry staff members,2006.

- Blood groups - ABO system.

- Many systems have been discovered to differnetiate bloog groups,the most famous system is ABO system.



- ABO system represent antigenic components on the surface of RBCs according to which
this system was made.
- O RBCS means that there is no antigens on the surface of RBCs so we can give O RBCS
to all other types of RBCs groups.

- B RBCS means that there is B antigens on the surface of RBCs so we can give B RBCS
Only to B person or AB person.

- A RBCS means that there is A antigens on the surface of RBCs so we can give A RBCS
Only to A person or AB person.

- AB RBCS means that there Are both A,B antigens on the surface of RBCs so we can give AB RBCS Only to AB person.

- Muscles.

-Types :-
There are 3 types of muscles each type of muscles has its specific structural and functional unit which is called muscle fiber ( cell):-
1- skeletal muscle has skeletal muscle fiber.
2- cardiac muscle has cardiac muscle fiber.
3- smooth muscle has smooth muscle fiber.

- Innervation of the muscles:-
*skeletal muscle fiber has somatic innervation.
* both cardiac muscle fiber and  smooth muscle fibers have autonomic innervation.
so
-skeletal muscle fiber is under voluntary control
- both cardiac muscle fiber and smooth muscle fibers are under involuntary control.

- Excitability.

-Def:- is the ability of cells to respond to stimuli.

-Excitability of cells and tissues is a basic function of life,as it is necessary for the functioning of nerves, muscles, and hormones,etc...

-The basis for the excitability of cells is their ion distribution, and the distribution of ions and molecules is determined by transport mechanisms associated with their plasma membrane structure.
-This structure permits and regulates various forms of ionic and molecular transport.

-Stimuli which induce Excitability are classified into two types:-
1-electrical. (galvanic ,faradric)
2-chemical.( ions , chemical transmitters, gases,……etc)

-you must know that:-
Excitable cells are those that can be stimulated to create a tiny electric current which in turn is transformed into physiological function and excitable cells are of three types:-

• Muscle cells.
• Nerve cells (neurons).
• Glandular cells.

-Three in human ear.

There are...

- 3 parts of the human ear:-

1. External ear.
2. Middle ear.
3. Inner ear.

- 3 parts of the External ear:-

1. auricle (pinna).
2. external auditory meatus.
3. Tympanic membrane.

- 3 layers in tympanic membrane:-

1. Outter skin layer.
2. middle fibrous layer.
3. inner mucosal layer.

- 3 cranial nerves innervate the tympanic membrane:-

1. C.N. V (trigeminal).
2. C.N. IX(glossopharyngeal).
3. C.N. X (Vagus).

 -3 Parts of middle ear:-

1. Tympanic cavity.
2. Eustachian tube.
3. Mastoid air cells.

- 3 parts of the tympanic cavity:-

1. epi-tympanum.
2. meso-tympanum.
3. hypo-tympanum.

- 3 middle ear bones (auditory ossicles):-

1. malleus.
2. incus.
3. stapes.

- 3 parts of the malleus:-

1. Head.
2. lateral process.
3. handle.

- 3 parts of labyrinth:-

1. Bony cochlea.
2. 3 semicircular canals.
3. Vestibule.

- 3 semicircular canals :

1. Posterior.
2. lateral.
3. superior.

- 3 compartments of cavity of bony cochlea :-

1. scala vestibuli: Upper compartment.
2. scala media (cochlear duct):middle compartment.
3. scala tympani: lower compartment.

- 3 membranes in cochlear duct:-

1. vestibular.
2. Tectorial.
3. Basilar .

- 3 labyrnthine sensory end organs:-

1. Of cochlea..called organ of corti.
2. of s c c....called crista.
3. of utricle and saccule..called macula.

Enjoy it,,,,,
Dr Ibrahim...

- DNA strucure and terminology.

Chromosomes are thread-like structures located inside the nucleus of cells. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.

see the picture which illustrate that also show the true genetic content & non genetic areas....

Promoters: are DNA sequences adjacent to the beginning of the genes and control gene activation.

 

Introns are sequences inside the gene although they do not code for protein sequence they are necessary for correct coding.

 

Exons are the regions inside the gene between introns that contain the coding DNA sequences. 

 

Most of the harmful mutations occur in exons and as a consequence change the structure of the coded protein.

 

- Cranial nerves.

**There are 12 cranial nerves...

1. I      Olfactory nerve (purely sensory).
2. II     Optic nerve  (purely sensory).
3. III    Occulomotor nerve  ( Purely motor).
4. IV    Trochlear  nerve  ( Purely motor).
5. V     Trigeminal nerve ( Mixed ).
6. VI    Abducent. ( Purely motor).
7. VII   Facial  ( Mixed ).
8. VIII  Auditory nerve  (Vestibulocochlear) (purely sensory).
9. IX    Glossopharyngeal  ( Mixed ).
10. X     Vagus  ( Mixed ).
11. XI    Spinal Accessory.( Mixed ).
12. XII   Hypoglossal .( Mixed ).

** Important notes:-

- The largest cranial nerve .... CN V (Trigeminal).
- Cranial nerves responsible for eye movements are

•    III (Oculomotor)
•    IV (Trochlear)
•    VI (Abducens)

- The longest cranial nerve ....CN X (Vagus) which reaches from the medulla to the digestive and urinary organs.


- CN I and II are  attached to Cerebrum.

See you ,

Ibrahim

- Three in nervous system.

* Brain is composed of three parts :-

1. Cerebrum.
2. Cerebellum.
3. Brain stem.

* Brain stem is composed of three parts :-

1. Midbrain.
2. Pons.
3. Medulla oblongata.

To be continued ....

- Excitability and Membrane Electropotential .

Excitability and Membrane Electropotential

Excitability of cells and tissues is a basic function of life.

Also known as irritability, it is the ability of cells to respond to

stimuli, excitability is necessary for the functioning of nerves,

muscles, and hormones, among other things.

The basis for the excitability of cells is their ion distribution, and

the distribution of ions and molecules is determined by transport

mechanisms associated with their plasma membrane structure.

This structure permits and regulates various forms of ionic

and molecular transport.

*The stimuli are classified into two types:-

1-electrical. (galvanic ,faradric)

2-chemical.( ions , chemical transmitters,gases,……etc)


* Excitable cells are those that can be stimulated to create a

tiny electric current e.g,

• Muscle cells .
• Nerve cells (neurons) .
• Glandular cells.
  

*There are 3 types of muscles :

each muscle has a structural & functional unit

which is muscle fiber ( cell):-

1- skeletal muscle ….. skeletal muscle fiber.

2- cardiac muscle…… cardiac muscle fiber.

3- smooth muscle …..smooth muscle fiber.