In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: We have previously demonstrated that endothelial - mesenchymal - transition ( EndoMT ) contributes to the early development of renal interstitial fibrosis independently of microalbuminuria in mice with streptozotocin ( STZ ) - induced diabetes .
### Output Text:
We have previously demonstrated that endothelial - mesenchymal - transition ( EndoMT ) contributes to the early development of renal interstitial fibrosis independently of microalbuminuria in mice with <span class="chemical">streptozotocin</span> ( <span class="chemical">STZ</span> ) - induced diabetes . 