This is the 7143rd most frequent Russian word.
брюно
The word "брюно" does not exist in standard Russian; it may be a typo or a misunderstanding.
In this case, 'Брюно' is referenced as part of a memory, maintaining its status as a proper noun.
Название деревни напомнило мне Брюно.
The name of the village reminded me of Bruno.
In this sentence, 'Брюно' is used as a proper noun, specifically a name.
Брюно приехал в город на поезде.
Bruno arrived in the city by train.
Here, 'Брюно' continues to function as a proper noun referring to a specific individual.