Evidence map›Paper›PMID 34774809›Full record

ArticleThe ocular surface2022

Human meibum and tear film derived cholesteryl and wax esters in meibomian gland dysfunction and tear film structure.

Safal Khanal, Yuqiang Bai, William Ngo, Kelly K Nichols, Landon Wilson, Stephen Barnes, Jason J Nichols

Open access · greenAbstract read
In one paragraph

Article in The ocular surface, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.

0numbers the graph read from it
0cells of the map it votes in
16citing papers in PubMed
3.1field-weighted citation impact, top 8% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

16 citing papers in PubMed, 23 citations in OpenAlex.

  1. Article
  2. Article
  3. Article
  4. Article
  5. Exploring the Effects ofAnimals : an open access journal from MDPI · 2025
    Article
  6. Impact of Hyperglycemia on Tear Film and Meibomian Gland Dysfunction: A Cross-Sectional Study.Diabetes, metabolic syndrome and obesity : targets and therapy · 2025
    Article
  7. Article
  8. Article
  9. Review
  10. Meibum Lipidomic Analysis in Evaporative Dry Eye Subjects.International journal of molecular sciences · 2024
    Article
  11. Article
  12. Article
  13. Review
  14. Review
  15. Article
  16. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 3 institutions in 2 countries.

Safal KhanalDepartment of Optometry and Vision Science, School of Optometry, University of Alabama at Birmingham, Birmingham, AL, USA.
Yuqiang BaiDepartment of Optometry and Vision Science, School of Optometry, University of Alabama at Birmingham, Birmingham, AL, USA.
William NgoCentre for Ocular Research & Education, School of Optometry & Vision Science, University of Waterloo, Waterloo, Ontario, Canada; Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong.
Kelly K NicholsDepartment of Optometry and Vision Science, School of Optometry, University of Alabama at Birmingham, Birmingham, AL, USA.
Landon WilsonDepartment of Pharmacology and Toxicology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; Targeted Metabolomics and Proteomics Laboratory, University of Alabama at Birmingham, Birmingham, AL, USA.
Stephen BarnesDepartment of Pharmacology and Toxicology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; Targeted Metabolomics and Proteomics Laboratory, University of Alabama at Birmingham, Birmingham, AL, USA.
Jason J NicholsDepartment of Optometry and Vision Science, School of Optometry, University of Alabama at Birmingham, Birmingham, AL, USA. Electronic address: jjn@uab.edu.
University of Alabama at Birmingham · USTarget (United States) · USUniversity of Waterloo · CA

Funding

National Dissemination of I-Corps@NCATS: Accelerating Translation through CommercializationUL1TR003096 · NCATS · UNIVERSITY OF ALABAMA AT BIRMINGHAM · PI GUTIERREZ, ORLANDO M, KIMBERLY, ROBERT P. · 2019 to 2023
$43.6M
Visual Phenotyping CoreP30EY003039 · NEI · UNIVERSITY OF ALABAMA AT BIRMINGHAM · PI Paul Douglas Gamlin · 1985 to 2026
$16.9M
The role of (O-acyl)-omega-hydroxy fatty acids in human lipid layer structure and function in health and meibomian gland dysfunction.R01EY026947 · NEI · UNIVERSITY OF ALABAMA AT BIRMINGHAM · PI NICHOLS, JASON JAY · 2016 to 2020
$1.8M
5500 Q-Trap Mass SpectrometerS10RR027822 · NCRR · UNIVERSITY OF ALABAMA AT BIRMINGHAM · PI BARNES, STEPHEN · 2010 to 2010
$469k
NCATS NIH HHS UL1 TR003096NCRR NIH HHS S10 RR027822NEI NIH HHS P30 EY003039NEI NIH HHS R01 EY026947
6 · The paper itself

Abstract

purposeThis study evaluated the presence and roles of cholesteryl esters (CEs) and wax esters (WEs) from human tear film and meibum in meibomian gland dysfunction (MGD).

methodsOut of 195 enrolled subjects, 164 and 179 subjects provided tear and meibum samples, respectively. Subjects were classified into normal, asymptomatic MGD, MGD, and mixed (MGD & aqueous deficient). The precorneal tear film (PCTF) thinning rate (evaporation) was measured using optical coherence tomography. Lipids extracted from tear and meibum samples were infused into a SCIEX 5600 TripleTOF mass spectrometer. CE and WE intensities quantified with Analyst 1.7 TF and LipidView 1.3 were compared across disease groups in MetaboAnalyst 5.0 and correlated with PCTF thinning rates.

resultsThe numbers of unique CEs and WEs identified in the samples were 125 and 86, respectively. Unsupervised Principal Component (PC) analysis and supervised Partial Least Square Discriminant analysis exhibited little separation among groups for both CEs and WEs in tears and meibum. Spearman's correlation analyses showed no association between either the first or second PC scores with PCTF thinning rates.

conclusionThe abundances of human PCTF and meibum-derived CEs and WEs were independent of MGD disease status and PCTF thinning (evaporation). CEs and WEs alterations do not contribute to alterations in tear film dynamics in MGD, such as has been demonstrated by the (O-acyl) ω-hydroxy fatty acids (OAHFAs).

Indexed as

Meibomian Gland DysfunctionEstersFatty AcidsHumansMeibomian GlandsTearsEstersFatty AcidsCholesteryl esterDry eye diseaseEvaporative dry eyeLipidsMeibomian gland dysfunctionMeibumTear filmWax ester

Identifiers

PMID34774809
PMCPMC9875797
OpenAlexW3212305861

What Socratic holds

Textmetadata
LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.