Good online sites

Blue Histology: http://www.lab.anhb.uwa.edu.au/mb140/
Cell Biology (Dr. Gwen V. Childs): http://www.cytochemistry.net/Cell-biology/
Ed's Basic Histology Gallery: http://www.pathguy.com/histo/000.htm
Histology Learning System (Common Confusions): http://www.bu.edu/histology/m/append04.htm
Histology at SIU SOM: http://www.siumed.edu/~dking2/index.htm
Histology Tutorial: http://medinfo.ufl.edu/year1/histo/
Üldine histoloogia: http://raud.ut.ee/~rraid/index/Uldine%20histoloogia/
NCBI Bookshelf: http://www.ncbi.nlm.nih.gov/sites/entrez?db=Books

What have I been doing.

I've gone through cell cytoplasm, epithelium and connective tissue. Made good notes on paper on nucleus, haven't have time to update notes here.
I also found some good histology and cell biology sites online which I will list next time.

2. Cell nucleus

Components:

1. nucleus membrane (envelope)
   
2. nucleolus


3. chromatine

Most of the cells have 1 round-shaped, loosely-packed nucleus.

Variations:

• relatively small nucleus with tightly backed contents (e.g. cells lining the blood spaces (sinusoids) of the liver (you can't see nucleolus in these nuclei);


• extraordinarily large nucleus (megakaryocytes);


• nucleus of distinctive shape (deeply segmented nucleus of neutrophils);


• binucleated (occasionally some hepatocytes and muscle cells of the heart);


• multinucleated (osteoclasts and sceletal muscle cells);


• without nucleus (erythrocytes, platelets).

Nuclear membrane is composed of 2 parallel unit membranes that fuse with each other at certain regions to form perforations knows as nuclear pores. It can be seen in EM.

• perinuclear cisterna (a 10 - to 30-nm space between two membranes);
  
• inner nuclear membrane (about 6 nm thick, faces the nuclear contact). It's in the close contact with the nuclear lamina which is made up of three polypeptides, called lamins (lamins A, B and C). It's a meshwork of intermediate filaments, 80 to 100 nm thick. Peripheral chromatin adheres to the inner aspectof the nuclear lamina. Certain integral proteins of the inner nuclear membrane act either directly or via other nuclear matrix proteins as contact sites for the nuclear RNAs and chromosomes.
  
• outer nuclear membrane (about 6 nm thick, is studded with ribosomes and faces the cytoplasm). It's continous with rough endoplasmatic reticulum. Its cytoplasmatic surface is surrounded by a thin, loose meswork of the intermediate filaments, vimentin. Its cytoplasmatic surface usually possesses ribosomes, actively synthesizing transmembrane proteins that are destined for the outer or inner nuclear membrane.
  
• nuclear pores (there are 20 - 3000 in one nucleus). It's surrounded by nonmembranous structures embedded in its rim - nuclear polar complex (NPC). It guards selectively passage through the pore.

Nuclear pore complex is composed of nuclear pore and its associated glycoproteins.

- cytoplasmic ring

- middle ring

- nucleoplasmic ring

1. Introduction to Histology

Covered introduction to histology and started the review of cell nucleus.
Brief notes.


Histology - a science of the tissues.

Basic tissues:
1. epithelial
2. connective
3. nervous
4. muscle
Mõtle, kas tean: For example where do liver belong to?


Three primary components that make up the body tissue:
1.cells
2.intercellular (extracellular) matrix (produced by the cells of connective tissue)
3.body fluids (blood plasma, interstitial fluid, lymph).

• preparation of histologic sections

Routinely prepared by the paraffin technique. If tissues need to be examined without delay, tissue freezing is used (f.e. the course of surgical procedure depends on rapid histological assessment of the nature or spead of a diseased tissue).

• coloring of stains

Histological stains reveal tissue components either by coloring them selectively (LM) or by increasing their optical densities to different extents (EM).

Hematoxylin-eosin stained sections:

a)hematoxylin (basic/cationic stain) colors the acidic components (basophilic) of the cell a bluish-purple color (DNA, RNA);

b)eosin (acid/anionic stain) colors basic (acidophilic) components of the cell a pinkish colors (positive (e.g.NH3) sites on fixed proteins).

• light microscope (LM)

The max magnification about x 1400. The limit of resolution 0,2 mcm (details that are less than 0,2 mcm apart cannot be distinguished as separate entities.)

• elecron microscopy (EM)

Magnification up to x 50000, resolution 1 nm. a)transmission EM (routinely used);

b)scanning EM.

• interpreting histologic sections in three dimensions (transverse, longitudinal, oblique and grazing sections).

Mõtle: microscopic appearance of tubes, partitions, proteins, stored carbohydrates, stored fat.

Recognition of extracellular matrix and bodu fluids in sections.

Artifacts (postmortem degeneration, shrinkage artifact, precipitate, wrinkles or folds, microtome knife nicks, rough handling).

• localization of specific tissue constituents

Mõtle: fluorescence microscope, immunofluorecence staining, confocal microscope, blotting techiques and in situ hybridization (Northern, Southern and Western Blots).

Starting my medical career again?

I have no idea whether I will ever work as a doctor again and if yes whether then in Estonia or in the USA. But I felt that it's still a good idea to refresh my memory on basic medical knowledge.
Anyway, I have 7 books coming from Amazon and yesterday I also took 2 histology and an anatomy book from the collage library.
So here it comes - to track my progress or the lack of progress.... just some notes. I thought that it would be better to keep them in English. Just for the reason of practise and also as all the books, which I'm going to read, are in English. And after all, nobody would ever ask me this stuff in Estonian again. If I'm not going to work as a doctor, then it's just for myself - to broaden my hosrizons. I've really forgotten a lot of all of this which I studied 15 years ago.