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Levels of normal and abnormally phosphorylated tau in different cellular and regional compartments of Alzheimer disease and control brains
Khatoon S, Grundke-Iqbal I, Iqbal K.. FEBS letters, 1994-08-01
Topic: Amyloid, tau and blood-test diagnosis
Microtubule associated protein tau is abnormally phosphorylated in Alzheimer disease (AD) brain. In the present study we investigated (i) whether tau is axonal or both axonal and somatodendritic, (ii) whether tau is a marker of Alzheimer neurofibrillary pathology, and (iii) whether the levels of tau in the cytosol (100,000 x g supernate) from AD brain are altered. Frozen autopsied tissue from 20 AD, 17 normal aged and 15 neurological control cases obtained 3-8 h postmortem were analyzed.
Key findings
- In the present study we investigated (i) whether tau is axonal or both axonal and somatodendritic, (ii) whether tau is a marker of Alzheimer neurofibrillary pathology, and (iii) whether the levels of tau in the cytosol (100,000 x g supernate) from AD brain are altered.
- Frozen autopsied tissue from 20 AD, 17 normal aged and 15 neurological control cases obtained 3-8 h postmortem were analyzed.
- Levels of normal, total, and abnormally phosphorylated tau were determined by a radioimmunoslot-blot assay using mAb Tau-1 as the primary antibody.
- Both frontal gray matter homogenate and cytosol from normal brains had 30-45% higher levels of normal tau than the corresponding fractions from the white matter.
Why it matters
This study measured levels of normal and abnormally phosphorylated tau in different parts of brain tissue from people who had died with Alzheimer disease and from controls. It is a postmortem tissue analysis and does not test any treatment, cure, or prevention.
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Study details
- Evidence strengthLow
How this study scored 39/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (FEBS letters) |
| Journal's citation record | 3 / 4 | FEBS Letters: journal h-index 393 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1994 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 5 / 7 | Cited 167 times (OpenAlex, 2026-10-10) |
| Citations per year | 2 / 5 | 4.9 citations a year over 34 year(s) since 1994 |
| Impact for its field and year | 1 / 6 | Cited 0.9× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 8 other studies in this library |
| Still being cited | 1 / 4 | Cited 10 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Khalid Iqbal: h-index 112 (OpenAlex, whole career) |
| Institution's track record | 0 / 3 | New York State Office for People With Developmental Disabilities: institution h-index 138 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 8076698) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 39 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Khatoon, S., Grundke-Iqbal, I., & Iqbal, K. (1994). Levels of normal and abnormally phosphorylated tau in different cellular and regional compartments of Alzheimer disease and control brains. FEBS letters. https://doi.org/10.1016/0014-5793(94)00829-9
Vancouver
Khatoon S, Grundke-Iqbal I, Iqbal K. Levels of normal and abnormally phosphorylated tau in different cellular and regional compartments of Alzheimer disease and control brains. FEBS letters. 1994. doi:10.1016/0014-5793(94)00829-9. PMID: 8076698.
BibTeX
@article{khatoon1994-8076698,
author = {Khatoon, S. and Grundke-Iqbal, I. and Iqbal, K.},
title = {{Levels of normal and abnormally phosphorylated tau in different cellular and regional compartments of Alzheimer disease and control brains}},
journal = {FEBS letters},
year = {1994},
doi = {10.1016/0014-5793(94)00829-9},
pmid = {8076698},
url = {https://doi.org/10.1016/0014-5793(94)00829-9}
}
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