haem-

American  

Chiefly British.

1. variant of hem-.

   haemangioma.

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haem ¹ British  

/ hiːm /

noun

1. biochem a complex red organic pigment containing ferrous iron, present in haemoglobin

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haem- ² British  

combining form

1. Also (US): hem-.  a variant (before a vowel) of haemo-

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Usage

What does haem- mean? Haem- is a combining form used like a prefix meaning “blood.” It is used in many medical terms, especially in pathology.Haem- comes from the Greek haîma, meaning “blood.”Chiefly used in British English, the combining form haem- is a variant of hem-, itself a variant of hemo- before a vowel.Want to know more? Read our Words That Use hem- and hemo- articles. Historically, haem- has been written as hæm-, featuring a ligature of the a and e.Other variants of haem- used like hemo- are hema-, hemat-, and hemato-. As with haem-, all these combining forms are often spelled with an additional a in British English, as in haema-, haemo-, haemat-, and haemato-.Also closely related to haem- are -aemia, -emia, -haemia, and -hemia, which are combined to the ends of words to denote blood conditions.

Etymology

Origin of haem

C20: shortened from _haematin

Example Sentences

The authors discovered that mitochondrial dysfunction caused HRI to phosphorylate eIF2α even when haem was plentiful, which was surprising, given that HRI activation had been thought to depend on haem depletion11,12.

From Nature

These drugs bind to the released haem in the digestive vacuole and prevent the compound’s detoxification by the parasite — in effect, poisoning the parasite with its own metabolic debris4.

From Nature

Haem is potentially toxic, and antibodies against the degradation protein reduce the worm’s ability to eliminate haem from its blood meals.

From Nature

One protein degrades haem, a component of the blood protein haemoglobin.

From Nature

Several RNAi programmes for liver conditions are also under way, including the development of Alnylam’s givosiran, which helps to prevent the production of neurotoxic metabolites of haem, a molecule found in red blood cells, that accumulate in people with acute hepatic porphyria.

From Nature