PMID- 23267848
OWN - NLM
STAT- MEDLINE
DCOM- 20130805
LR  - 20191210
IS  - 1522-9653 (Electronic)
IS  - 1063-4584 (Linking)
VI  - 21
IP  - 3
DP  - 2013 Mar
TI  - Cluster analysis of infrared spectra can differentiate intact and repaired 
      articular cartilage.
PG  - 462-9
LID - S1063-4584(12)01050-3 [pii]
LID - 10.1016/j.joca.2012.12.005 [doi]
AB  - OBJECTIVE: Successful repair of articular cartilage (AC) defects would be a major 
      advantage due to the low ability of AC to heal spontaneously. Sensitive methods 
      to determine changes in AC composition and structure are required to monitor the 
      success of repair. This study evaluates the ability of unsupervised cluster 
      analysis applied to Fourier transform infrared (FTIR) microspectroscopy to 
      discriminate between healthy and repaired AC. METHODS: Osteochondral lesions 
      (3 mm in depth) were surgically created in patellar grooves of rabbit femurs and 
      were either left to heal spontaneously (n = 6) or surgically repaired with 
      autologous chondrocytes in type II collagen gel (n = 6). After 6 months, tissues 
      were harvested, FTIR microspectroscopy was conducted and Fuzzy c-means (FCM) 
      cluster analysis applied to spectra of pairs of intact and repaired AC samples 
      from each rabbit. Two spectral regions [amide I and carbohydrate (CHO)] were 
      analyzed and the results from the two types of repair were compared. RESULTS: Two 
      separate regions of repair were detected with FCM. The estimated proteoglycan 
      content (from CHO region) in the repaired AC was significantly lower than that in 
      intact AC. The spontaneously repaired AC was better distinguished from the intact 
      AC than the collagen II gel repaired AC. The most distinct clustering was 
      observed for spontaneously repaired samples using CHO region. CONCLUSIONS: This 
      study revealed that unsupervised cluster analysis applied to FTIR 
      microspectroscopy can detect subtle differences in infrared spectra between 
      normal and repaired AC. The method may help in evaluation and optimization of 
      future AC repair strategies.
CI  - Copyright (c) 2012 Osteoarthritis Research Society International. Published by 
      Elsevier Ltd. All rights reserved.
FAU - Kobrina, Y
AU  - Kobrina Y
AD  - Department of Applied Physics, University of Eastern Finland, Finland.
FAU - Rieppo, L
AU  - Rieppo L
FAU - Saarakkala, S
AU  - Saarakkala S
FAU - Pulkkinen, H J
AU  - Pulkkinen HJ
FAU - Tiitu, V
AU  - Tiitu V
FAU - Valonen, P
AU  - Valonen P
FAU - Kiviranta, I
AU  - Kiviranta I
FAU - Jurvelin, J S
AU  - Jurvelin JS
FAU - Isaksson, H
AU  - Isaksson H
LA  - eng
PT  - Evaluation Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20121223
PL  - England
TA  - Osteoarthritis Cartilage
JT  - Osteoarthritis and cartilage
JID - 9305697
RN  - 0 (Amides)
RN  - 0 (Carbohydrates)
RN  - 0 (Collagen Type II)
RN  - 0 (Proteoglycans)
SB  - IM
MH  - Amides/analysis
MH  - Animals
MH  - Carbohydrates/analysis
MH  - Cartilage, Articular/chemistry/*pathology
MH  - Chondrocytes/transplantation
MH  - Cluster Analysis
MH  - Collagen Type II/therapeutic use
MH  - Femur/chemistry/*pathology
MH  - Hindlimb
MH  - Proteoglycans/analysis
MH  - Rabbits
MH  - Spectroscopy, Fourier Transform Infrared/methods
MH  - Wound Healing/*physiology
EDAT- 2012/12/27 06:00
MHDA- 2013/08/06 06:00
CRDT- 2012/12/27 06:00
PHST- 2012/04/18 00:00 [received]
PHST- 2012/11/27 00:00 [revised]
PHST- 2012/12/14 00:00 [accepted]
PHST- 2012/12/27 06:00 [entrez]
PHST- 2012/12/27 06:00 [pubmed]
PHST- 2013/08/06 06:00 [medline]
AID - S1063-4584(12)01050-3 [pii]
AID - 10.1016/j.joca.2012.12.005 [doi]
PST - ppublish
SO  - Osteoarthritis Cartilage. 2013 Mar;21(3):462-9. doi: 10.1016/j.joca.2012.12.005. 
      Epub 2012 Dec 23.