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: In our patient , both supraphysiologic levels of plasma catecholamines and stress related neuropeptides caused by cancer diagnosis as well as chemotherapy may have contributed the development of ABS .
### Output Text:
In our patient , both supraphysiologic levels of plasma <span class="chemical">catecholamines</span> and stress related neuropeptides caused by cancer diagnosis as well as chemotherapy may have contributed the development of ABS . 