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: Modest increases in HDL - cholesterol levels of about 10 % are also reported .
### Output Text:
Modest increases in HDL - <span class="chemical">cholesterol</span> levels of about 10 % are also reported . 