English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The morphological changes caused by freezing and thawing human testicular spermatozoa have been assessed here. Retrieval of testicular biopsies was carried out on six patients with obstructive azoospermia preparatory to intracytoplasmic sperm injection (ICSI). Light microscope analysis was carried out on testicular cells and ultrastructural analysis was carried out on spermatozoa and different spermatid stages before and after the freezing procedure. Upon examination under light microscopy, all germ cells presented increased vacuolization in their cytoplasm and shrinkage or swelling of the nuclei and cytoplasmic membranes. These altered structures were accentuated in the spermatocyte I cell which often presented disrupted membranes. The ultrastructural findings under transmission electron microscopy demonstrated that after freezing and thawing the major types of cryoinjury were the swelling and rupture of inner and outer acrosomal and plasma membranes. The acrosome material often appeared as dispersed material or as condensed spots or was even lost. Such damage was observed mainly at the spermatozoa and late spermatid stages. We conclude that the freezing and thawing of testicular biopsies causes similar morphological damage to testicular spermatozoa and frozen-thawed ejaculated spermatozoa. It is still unclear whether these changes in testicular spermatozoa after freezing and thawing may compromise its use in the ICSI procedure.

Light and electron microscopic analysis of human testicular spermatozoa and spermatids from frozen and thawed testicular biopsies