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: After 2 individuals with psoriasis developed a capillary leak syndrome following treatment with oral sirolimus lesional skin cells and activated peripheral blood cells were analyzed for induction of apoptosis .
### Output Text:
After 2 individuals with psoriasis developed a capillary leak syndrome following treatment with oral <span class="chemical">sirolimus</span> lesional skin cells and activated peripheral blood cells were analyzed for induction of apoptosis . 