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This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

✓ Peer-reviewed alzhub usefulness score 40 out of 100. Disease mechanisms

Topic: Gut, metabolism and diet

Reductions in cerebral metabolism sufficient to impair cognition in normal individuals also occur in Alzheimer's disease (AD). The degree of clinical disability in AD correlates closely to the magnitude of the reduction in brain metabolism. Therefore, we tested whether impairments in tricarboxylic acid (TCA) cycle enzymes of mitochondria correlate with disability. Brains were from patients with autopsy-confirmed AD and clinical dementia ratings (CDRs) before death. Significant (p < 0.01) decreases occurred in the activities of the pyruvate dehydrogenase complex (-41%), isocitrate dehydrogenase (-27%), and the alpha-ketoglutarate dehydrogenase complex (-57%). Activities of succinate dehydrogenase (complex II) (+44%) and malate dehydrogenase (+54%) were increased (p < 0.01). Activities of the other four TCA cycle enzymes were unchanged. All of the changes in TCA cycle activities correlated with the clinical state (p < 0.01), suggesting a coordinated mitochondrial alteration. The highest correlation was with pyruvate dehydrogenase complex (r = 0.77, r2= 0.59). Measures to improve TCA cycle metabolism might benefit AD patients.

Key findings

Study details

How this study scored 40/100
How this study's score is builtJournal tier 9 of 10; Journal's citation record left out, no data; Study design 0 of 12; Strength of evidence 1 of 5; Peer-review validation 10 of 10; How recent 1 of 5; Sample size 0 of 4; Effect reported 0 of 3; Studied in people 0 of 3; Randomised / blinded 0 of 2; Times cited left out, no data; Citations per year left out, no data; Impact for its field and year left out, no data; Cited by studies here left out, no data; Still being cited left out, no data; Senior author's track record left out, no data; Institution's track record left out, no data; Multi-centre collaboration left out, no data; Indexed in PubMed 2 of 2; Free to read 0 of 2. 23 of the 58 points it could be judged on, which is 40 of 100. Total 40 of 100.23 of the 58 points we could judge = 40 of 100

Published in a leading specialty journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 23 of the 58 points we could judge it on, which is 40 out of 100.

ComponentPointsWhy
Journal tier 9 / 10 Tier 2 — leading specialty journal (Annals of Neurology)
Journal's citation record — / 4 No journal record from OpenAlex — left out of this score
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 2005 — 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 — / 7 No citation count (not found in OpenAlex) — left out of this score
Citations per year — / 5 No citation count or no year — left out of this score
Impact for its field and year — / 6 No field-weighted citation impact (OpenAlex has none yet) — left out of this score
Cited by studies here — / 6 Not yet checked against this library's citation graph — left out of this score
Still being cited — / 4 No yearly citation counts — left out of this score
Senior author's track record — / 4 Senior author's record not available — left out of this score
Institution's track record — / 3 No institution listed in OpenAlex — left out of this score
Multi-centre collaboration — / 3 Institutions not listed — left out of this score
Indexed in PubMed 2 / 2 Indexed in PubMed (PMID 15852400)
Free to read 0 / 2 Behind a paywall — scores zero
Points 23 / 58 Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 23 of the 58 points we could judge it on is 40 out of 100.
Total 40 / 100 —

What each of these 20 components measures, and what this score is not →

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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

Bubber, P., Haroutunian, V. H., Fisch, G. S., Blass, J. P., & Gibson, G. E. (2005). Mitochondrial abnormalities in Alzheimer brain: Mechanistic implications. Annals of Neurology. https://doi.org/10.1002/ana.20474

Vancouver

Bubber P, Haroutunian VH, Fisch GS, Blass JP, Gibson GE. Mitochondrial abnormalities in Alzheimer brain: Mechanistic implications. Annals of Neurology. 2005. doi:10.1002/ana.20474. PMID: 15852400.

BibTeX

@article{bubber2005-15852400,
  author  = {Bubber, Parvesh and Haroutunian, Vahram H. and Fisch, Gene S. and Blass, John P. and Gibson, Gary E.},
  title   = {{Mitochondrial abnormalities in Alzheimer brain: Mechanistic implications}},
  journal = {Annals of Neurology},
  year    = {2005},
  doi     = {10.1002/ana.20474},
  pmid    = {15852400},
  url     = {https://doi.org/10.1002/ana.20474}
}

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