In this task, you are given a sentence in the Spanish language. Your task is to translate the Spanish sentence into the English language.

Los ovillos neurofibrilares son estructuras anómalas que se observan en pacientes de alzheimer y que constan de

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
The neurofibrillary tangles are anomalous structures that are observed in Alzheimer's patients and that consist of