On the welcome page of the dictionary, three major sections are shown: Normal tissues, Cancer and Cell structure. Below the image of each section are links to introductory texts for i) normal tissue histology, ii) hallmarks of cancer, and iii) cell structure overview. For the cancer-section there is also a link to current cancer statistics (incidence, survival, etc) for Sweden and the rest of the world. Within each section there are direct links to histology descriptions of different tissue types and tumor forms as well as descriptions of cell structures.
For the 'Tissue & cell types' and 'Tumor' sections, tissue-slides stained with hematoxylin and eosin (HE) are shown at three different levels of magnification. On the top level, an overview of the whole tissue-sample is shown with boxes in black indicating where zoomed-in representative parts of the tissue are available for viewing. Clicking on these boxes will zoom in on that part to show tissue structures, cells and features in greater detail. Throughout these sections, arrows indicate relevant tissue structures, cell-types and other features.
For the 'Cell structure' section, immunofluorescent images of formaldehyde-fixed cell lines are shown. The various cell structures that are demonstrated are always shown in the green channel using an antibody found in the Human Protein Atlas. The antibody name is linked to the subcellular location summary page of the target gene. The other channels: nucleus, microtubules and endoplasmic reticulum, are always shown in the blue, red and yellow channels, respectively. The channels can be toggled on and off by clicking on the respective coloured button above the image. When applicable, the immunofluorescent images are complemented by immunohistochemically stained cells where the location of the particular cell structure is shown in brown.
A common feature for all sections is that a general descriptive text about the tissue, tumor-type or cell structure is provided when browsing a particular topic.
The main function of the testes is to produce the male germinal component (sperm) needed for reproduction and furthermore the testes are also important for the production of several hormones, including androgens. The testes are a paired organ, surrounded by layers of connective tissue, including the tunicaalbuginea. The testes are suspended in the scrotum by the spermatic chord, including the vas deferens. The testis is structured in lobules separated by fibrous septa. Each lobule contains 1-4 seminiferous ducts. The highly coiled seminiferousducts debouch into the rete testis, which connects to the vas deferens. The seminiferous ducts that are surrounded by a layer of thin connective tissue dominate the testes and contain germ cells and Sertolicells. Germ cells are derived from tissues in the yolk sac and are capable of undergoing meiosis in their maturation towards mature sperms. Maturation takes approximately 70 days. Germ cells comprise the bulk of cells present in seminiferous ducts. Several complex steps that include stages of maturation, can be morphologically determined and visualized in cross sections from seminiferous ducts. These stages include undifferentiated spermatogonia in the basal compartment followed by more luminal mature spermatocytes andspermatids. The Sertoli cells are hormone producing non-dividing columnar cells that are attached to the basement membrane and exhibit cytoplasmic extensions around the germinal cells. Sertoli cells have irregular nuclei with a typical prominent nucleoleus. The stroma surrounding the seminiferous ducts is composed of loose connective tissue containing hormone producing Leydig cells and blood vessels, lymphatics, nerves together with few macrophages and mast cells. The Leydig cells are found in small clusters or as single cells in the interstitium between seminiferous ducts. Typically Leydig cells display an abundant cytoplasm, containing lipid droplets and lipofuscin pigment, and a round, vesicular nucleus.
