Specimen Nr. 01A

Specimen:

Lymph node (Dog)

Staining:

H&E

Magnification:

10x

Important structures :

1.Adipose tissue
2.Capsule
3.Cortex
4.Secondary lymphoid follicle with germinal centre
5.Paracortex
6.Medulla
7.Hilum
Lymphknoten sind in Fettgewebe eingebettet und von einer Kapsel aus straffem Bindegewebe umgeben. Das Bindegewebe setzt sich scheidewandartig als Trabekel in das Innere fort und unterteilt den Lymphknoten segmentartig. Unter der Kapsel befindet sich die Rinde (Cortex), die Primär- und Sekundärfollikel enthält. Darunter schließt sich der Paracortex an, auf den das Mark (Medulla) folgt. Am Hilum tritt die versorgende Arterie ein, Vene und efferentes Lymphgefäß verlassen den Lymphknoten. Afferente Lymphgefäße, die gegenüber dem Cortex die Kapsel durchbrechen, sind auf diesem Schnitt nicht getroffen.

Legende:

Adipose tissue
Capsule
Cortex
Secondary lymphoid follicle with germinal centre
Paracortex
Medulla
Hilum

Localisation of organs of immune-lymphatic system[we]

1. Pharyngeal tonsil
2. Palatine tonsil
3. Lymph node
4. Lymphatic vessels
5. Spleen
6. Peyer's patches
7. Thymus

Hematoxylin and Eosin (H&E)

H&E is the most common survey stain, which shows cell nuclei and cytoplasmatic components.

Structures Colour
Nuclei blue
Cytoplasm pale red
Connective-tissue fibres
- Collagen
- Reticular
- Elastic

red
-
pale rose to red
Muscle tissue red
Erythrocytes red-orange

Dyes:

Hematoxylin (e.g. hemalaun, Weigerts or Heidenhains iron-hematoxylin)
Hematoxylin is a positively charged dye (at low pH values). It therefore colors negatively charged (basophilic) structures blue, like the DNA of nuclear chromatin, the RNA of rough endoplasmatic reticulum, and the acidic glycosaminoglycans of hyaline cartilage.
Hematoxylin used in the preparation of iron varnish is Weigerts or Heidenhains iron-hematoxylin and in the preparation of aluminum varnish is hemalaun.
Eosin Eosin is a negatively charged dye used for counterstaining. It stains all remaining structures different shades of red (acidophilic).

Thiazinrot

Thiazinrot behaves similar as eosin.
Die Lymphknoten sind in die Lymphbahnen eingeschaltete Filterstationen. Die Größe ruhender menschlicher Lymphknoten schwankt zwischen wenigen Millimetern bis über 1 cm in der Länge. Ihre Zahl liegt zwischen 300 und 700. Auch im hohen Alter nimmt die Anzahl der Lymphknoten nicht ab, sie sind nur kleiner. Wenn ein Lymphknoten die erste Filterstation für ein Organ ist, wird er als regionärer Lymphknoten bezeichnet, alle anderen werden Sammellymphknoten genannt.

Home
Tutor
Help
Exit
Boxes

Magnification:

10x

Magnification:

25x

Magnification:

100x

Magnification:

100x

Magnification:

400x

Magnifications
Adipose tissue
Capsule
Capsule
Cortex
Secondary lymphoid follicle with germinal centre
Secondary lymphoid follicle with germinal centre
Paracortex
Medulla
Hilum

HistoNet2000 - Help

1. Organization of the screen surface

Right side: histologic specimen
Left side: information about the specimen (above) and general program functions (below)

2.Histologic specimen

Pull the mouse across the histologic specimen for training purposes. A small square with exclamation marks (dynamic labels) will appear where there is an important structure. You should then decide what structure this could be. To check your result, simply click the appropriate square, and the correct label will appear. The option “marked” allows you to see all labels for all structures simultaneously. These can be removed by clicking “unmarked”. This reactivates the dynamic labels.

3. Complementary information

Info: general information about the specimen, as well as a list of the dynamic labels
Drawing: schematic drawing of the specimen
Staining: information about the staining method for this specimen
Knowledge: short texts with basic histologic information, presently deactivated

4. General Program Functions

Home: returns you to the “start” page
Tutor: how to contact the HistoNet Team
Help: Instructions for Use appear
Exit: closes down the HistoNet program
Boxes: goes back to the other specimen of a topic
VM: provides virtual microscopy

We hope you will enjoy working with HistoNet2000 and learn a lot from it!

Cose help