scholarly journals Obesity alters the collagen organization and mechanical properties of murine cartilage

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Amber T. Collins ◽  
Guoli Hu ◽  
Hunter Newman ◽  
Michael H. Reinsvold ◽  
Monique R. Goldsmith ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Light Microscopy ◽  
High Fat Diet ◽  
Polarized Light ◽  
Polarized Light Microscopy ◽  
Indentation Modulus ◽  
Knee Cartilage ◽  
High Fat ◽  
Collagen Organization ◽  
Significant Difference

AbstractOsteoarthritis is a debilitating disease characterized by cartilage degradation and altered cartilage mechanical properties. Furthermore, it is well established that obesity is a primary risk factor for osteoarthritis. The purpose of this study was to investigate the influence of obesity on the mechanical properties of murine knee cartilage. Two-month old wild type mice were fed either a normal diet or a high fat diet for 16 weeks. Atomic force microscopy-based nanoindentation was used to quantify the effective indentation modulus of medial femoral condyle cartilage. Osteoarthritis progression was graded using the OARSI system. Additionally, collagen organization was evaluated with picrosirius red staining imaged using polarized light microscopy. Significant differences between diet groups were assessed using t tests with p < 0.05. Following 16 weeks of a high fat diet, no significant differences in OARSI scoring were detected. However, we detected a significant difference in the effective indentation modulus between diet groups. The reduction in cartilage stiffness is likely the result of disrupted collagen organization in the superficial zone, as indicated by altered birefringence on polarized light microscopy. Collectively, these results suggest obesity is associated with changes in knee cartilage mechanical properties, which may be an early indicator of disease progression.

scholarly journals A polarized light microscopy method for accurate and reliable grading of collagen organization in cartilage repair

2011 ◽  
Vol 19 (1) ◽  
pp. 126-135 ◽  
Author(s):  
A. Changoor ◽  
N. Tran-Khanh ◽  
S. Méthot ◽  
M. Garon ◽  
M.B. Hurtig ◽  
...  
Keyword(s):  
Light Microscopy ◽  
Cartilage Repair ◽  
Polarized Light ◽  
Polarized Light Microscopy ◽  
Collagen Organization ◽  
Microscopy Method

scholarly journals Erosion Potential of Tooth Whitening Regimens as Evaluated with Polarized Light Microscopy

2015 ◽  
Vol 16 (11) ◽  
pp. 921-925 ◽  
Author(s):  
So Ran Kwon ◽  
Fang Qian ◽  
Patrick Brambert
Keyword(s):  
Light Microscopy ◽  
Polarized Light ◽  
Negative Control Group ◽  
Negative Control ◽  
Polarized Light Microscopy ◽  
Control Group ◽  
Tooth Whitening ◽  
Significant Difference ◽  
Enamel Erosion ◽  
Recommended Guidelines

ABSTRACT Aims Tooth whitening is a widely utilized esthetic treatment in dentistry. With increased access to over-the-counter (OTC) systems concerns have been raised as to potential adverse effects associated with overuse of whitening materials. Therefore, this study aimed to evaluate enamel erosion due to different whitening regimens when used in excess of recommended guidelines. Materials and methods Extracted human teeth (n = 66) were randomly divided into 11 groups (n = 6/group). Specimens were exposed to OTC products: Crest Whitestrips and 5-minute natural white and a do-it-yourself (DIY) strawberry whitening recipe. Within each regimen, groups were further divided per exposure time: specimens receiving the recommended product dosage; 5 times the recommended dosage; and 10 times the recommended dosage. Negative and positive controls were treated with grade 3 water and 1.0% citric acid, respectively. Specimens were nail-varnished to limit application to a 1 × 4 mm window. Following treatment, specimens were sectioned and erosion (drop in μm) measured using polarized light microscopy. Two-sample t-test was used to detect difference in amount of enamel erosion between negative and positive groups, while one-way analysis of variance (ANOVA), followed by post hoc Dunnett's test was used to detect difference between set of treatment groups and negative control groups or among all experimental groups. Results There was significant difference in mean amount of enamel erosion (p < 0.0001). Mean enamel erosion for positive control group was significantly greater than that for negative control group (23.50 vs 2.65 μm). There was significant effect for type of treatments on enamel erosion [F(9,50) = 25.19; p < 0.0001]. There was no significant difference between the negative control and each of treatment groups (p > 0.05 for all instances), except for Natural White_10 times treatment group (p < 0.0001) that was significantly greater than the negative control group (14.82 vs 2.65 μm). Conclusion Caution is advised when using certain over-thecounter products beyond recommended guidelines as there is potential for enamel erosion. Clinical significance Enamel erosion due to the overuse of whitening products varies for different modalities and products. Therefore, caution is advised when using certain over-thecounter products beyond recommended guidelines, as there is potential for enamel erosion. How to cite this article Brambert P, Qian F, Kwon SR. Erosion Potential of Tooth Whitening Regimens as Evaluated with Polarized Light Microscopy. J Contemp Dent Pract 2015;16(11):921-925.

scholarly journals Comparative Assessment of Primary Osteoarthritis Progression Using Conventional Histopathology, Polarized Light Microscopy, and Immunohistochemistry

Cartilage ◽  
2020 ◽  
pp. 194760352093845 ◽  
Author(s):  
V.P. Mantripragada ◽  
W. Gao ◽  
N.S. Piuzzi ◽  
C.D. Hoemann ◽  
G.F. Muschler ◽  
...  
Keyword(s):  
Light Microscopy ◽  
Healthy Adult ◽  
Femoral Condyle ◽  
Polarized Light ◽  
Polarized Light Microscopy ◽  
Current Standard ◽  
Superficial Zone ◽  
Collagen Organization ◽  
Primary Osteoarthritis ◽  
Early Primary

Objective Evaluation of collagen orientation and arrangement in articular cartilage can improve our understanding of primary osteoarthritis (OA) progression and targeted therapies. Our goal was to determine if polarized light microscopy (PLM) for collagen organization is useful in identifying early primary OA features in comparison to current standard histopathological methods. Design Osteochondral specimens from 90 total knee arthroplasty patients with relatively preserved lateral femoral condyle were scored using (1) histological-histochemical grading system (HHGS); (2) Osteoarthritis Research Society International (OARSI); (3) PLM-Changoor system for repair cartilage, scores ranging between 0 (totally disorganized cartilage) and 5 (healthy adult cartilage); and (4) new PLM system for primary OA cartilage with superficial zone PLM (PLM-SZ) and deep zone PLM (PLM-DZ) scores, each ranging between 0 (healthy adult SZ and DZ collagen organization) and 4 (total loss of collagen organization). Serial sections were stained for collagen I and II antibodies. Spearman correlation coefficients ( rs) were determined. Results The associations between: (1) PLM-Changoor and HHGS or OARSI were weak ( rs = −0.36) or moderate ( rs = −0.56); (2) PLM-SZ and HHGS or OARSI were moderate ( rs = 0.46 or rs = 0.53); and (3) PLM-DZ and HHGS or OARSI were poor ( rs = 0.31 or rs = 0.21), respectively. Specimens exhibiting early and mild OA (HHGS < 5 and OARSI < 8.6) had PLM-SZ and PLM-DZ scores between 0 and 4 and between 0 and 3, respectively, and indicated new histopathological features not currently considered by HHGS/OARSI. Conclusions PLM was effective at identifying early SZ and DZ collagen alterations that were not evident in the traditional scoring systems. Incorporating PLM scores and/or additional HHGS/OARSI features can help improve characterization of early primary OA cartilage.

Pengaruh Pemberian Ekstrak Anggur Laut terhadap Penurunan Kadar Kolesterol LDL Rattus norvegicus Jantan yang Mendapat Diet Tinggi Lemak

2020 ◽  
Vol 17 (2) ◽  
pp. 192
Author(s):  
RONALDO LAU ◽  
SULISTIANA PRABOWO ◽  
RIAMI RIAMI
Keyword(s):  
Cholesterol Level ◽  
Rattus Norvegicus ◽  
High Fat Diet ◽  
Ldl Cholesterol ◽  
White Male ◽  
Standard Diet ◽  
High Fat ◽  
Caulerpa Racemosa ◽  
Significant Difference ◽  
Male Wistar Rats

<p align="justify"><strong>ABSTRACT</strong><strong></strong></p><p align="justify"><strong>Background</strong>: High fat diet increase the absorption of lipid in the intestinum, that can lead to increase LDL cholesterol level in the blood. Sea grapes extract (<em>Caulerpa racemosa</em>) contains antioxidant polyphenolic group that can reduce MTP and ACAT-2 in the body that can decrease LDL cholesterol level in the blood.The purpose of this study is to know the effect of sea grapes extract  on decreasing LDL cholesterol of white male Wistar rats (<em>Rattus norvegicus</em>) fed with high fat diet.</p><p align="justify"><strong>Method</strong>:  24 white male Wistar rats, that divided into 3 groups: 1) group of rats fed with standard diet for 28 days; 2) group of rats fed with high fat diet for 28 days; 3) group of rats fed with high fat diet for 28 days and given 10 gram/kg body weight/day of sea grapes extract on 15<sup>th</sup>-28<sup>th</sup> days. Then the blood LDL cholesterol level measured on the 29<sup>th</sup> day.</p><p align="justify"><strong>Result :</strong> One-Way ANOVA Test showed there was significant difference (p=0.004) of LDL level between the group of rats fed with standard diet (12.37 mg/dl) compared to group of rats fed with high fat diet (17.87 mg/dl). There was significant difference (p=0.001) of LDL level between the group of rats fed with high fat diet (17.87 mg/dl) compared to group of rats fed with high fat diet and sea grapes extract (10.12 mg/dl).</p><p align="justify"><strong>Conclusion: </strong>high fat diet significantly increase blood LDL cholesterol level and sea grapes extract (<em>Caulerpa racemosa</em>) significantly decrease blood LDL cholesterol level.</p><p align="justify"> </p><p align="justify"><strong>Keywords :</strong>Sea grapes extract, LDL cholesterol, high fat diet</p>

Ferroelastic domains and phase transitions in organic–inorganic hybrid perovskite CH3NH3PbBr3

2021 ◽  
Author(s):  
Maryam Bari ◽  
Alexei A. Bokov ◽  
Zuo-Guang Ye
Keyword(s):  
Phase Transitions ◽  
Electric Field ◽  
Light Microscopy ◽  
Domain Structure ◽  
Polarized Light ◽  
External Stress ◽  
Polarized Light Microscopy ◽  
Inorganic Hybrid ◽  
Hybrid Perovskite ◽  
Ferroelastic Domains

Polarized light microscopy reveals twin domains and symmetry of the phases in CH3NH3PbBr3 crystal; domain structure remains unresponsive to electric field but changes under external stress, confirming ferroelasticity while ruling out ferroelectricity.

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