Scanning electron microscopic study of the human uterine tube epithelial lining: surgical biopsy samples and epithelial cell culture.

This article summarizes the importance of the exact morphology of human uterine/fallopian tube epithelium at the scanning electron microscopy (SEM) level for the clinical outcome even nowadays. Visual referential micrographs from SEM reflect two ways to view human epithelial cell lining surfaces: the surface epithelial uterine tube from surgical tissue biopsy and human fallopian tube epithelial cells (HFTEC) culture monolayer surface. One colorized image visualizes ciliated cells, distinguishes them from non-ciliated cells, and provides an educational benefit. A detailed description of the ultrastructure in referential and pathologic human uterine tube epithelium is important in defining the morphological basis of high-grade carcinomas, in the mechanism of pathophysiology, and in discussing options for its prevention. Cell cultures of human fallopian tube epithelial cells offer new approaches in simulating the mechanisms of cancer genesis or may help to elucidate the genetic basis of several diagnoses. New technical approaches in SEM provide higher resolution and detailed surface images. The SEM modality is still one of the current options in diagnostics and may be useful for advancing human reproductive organ cancer research.

Ependymal cells surface of human third brain ventricle by scanning electron microscopy.

OBJECTIVES: The ependymal lining of the human brain ventricular system displays distinct structural differences and functional heterogeneity among individual ependymal cells (ECs). To date, multi-ciliated ECs (E1 cells), bi-ciliated ECs (E2 cells), uni-ciliated ECs (E3 cells), ECs without cilia, and ECs with cytoplasmic protrusions have been described in human brain ventricles. METHOD: Using scanning electron microscopy (SEM), we evaluated ependymal samples from 6 defined regions of the third ventricle from 9 human brains. These regions were strictly defined according to the periventricular structures they neighbour with. RESULTS: We observed different structures on the apical surface of the ECs. Various ECs differed from each other by the presence of microvilli, secretory bodies, and a variable number of cilia, which led us to divide the ECs into several exactly specified types according to their apical morphology. CONCLUSION: We found all types of ECs in every examined region with a predominance of particular types of apical surface of ECs in the individual areas (Tab. 4, Fig. 7, Ref. 22).

Merkel cells--review on developmental, functional and clinical aspects.

The objective of this review is to introduce Merkel cells, to provide a basic overview on the theoretical background of function, development and clinical importance of Merkel cells. Merkel cells (MCs) are post-mitotic neuroendocrine cutaneous cells primarily localized in the epidermal basal layer of vertebrates and concentrated in touch-sensitive areas in glabrous, hairy skin and in some mucosa. There is a great site variation in the density of MCs. In routine light microscopy human MCs can hardly be identified. Cytokeratine 20 is a reliable marker with highest degree of specifity. MCs can be also distinguished by electron microscopy. The origin of human MCs has been controversial. Some investigators believe that it is a neural crest derivate, whereas others have proposed that it is a differentiation product of the fetal epidermal keratinocytes. Most studies focus on neuroendocrine functions and their possible malignant transformation into Merkel cell carcinomas (MCC). MCC is an uncommon and often aggressive malignancy and found mainly in elderly patients. It occurs most frequently in the head and neck region. MCC may be difficult to diagnose, it appears as a firm, painless lump. Diagnosis is based on typical histology representation on haematoxylin-eosin stained slides together with the results of immunohistochemistry. Histologically, MCC has been classified into three distinct subtypes: trabecular, intermediate and small cell type. Radical surgery is the recomended procedure for the treatment of primary MCC. Oncological treatment is generally reserved for stage III. (distant metastases) cases of MCC (Tab. 1, Fig. 13, Ref. 58). Full Text in free PDF www.bmj.sk.