hes

Hes is a term that can refer to several distinct concepts depending on context. It is not a single topic with a universal definition and may appear in biology, medicine, or informal writing.

In biology, Hes refers to the hairy and enhancer of split gene family, which encodes basic helix–loop–helix transcription factors acting downstream of Notch signaling. Members such as Hes1 and Hes5 regulate cell fate during development by repressing differentiation and maintaining progenitor states.

In medicine, hydroxyethyl starch (HES) is a synthetic colloid used as a plasma volume expander. Its safety has been questioned due to risks of kidney injury and coagulopathy, leading to restricted use in many guidelines. Formulations differ in molecular weight and substitution, affecting their safety profile.

In informal writing, hes may appear as a nonstandard rendering of the contraction he's when apostrophes are omitted, though this is generally discouraged in formal contexts.

Beyond these uses, HES or Hes can be an acronym for various organizations, standards, or systems. The intended meaning depends on context.