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1.
Micromachines (Basel) ; 14(4)2023 Mar 28.
Article in English | MEDLINE | ID: mdl-37420980

ABSTRACT

This paper presents a direct numerical simulation for the extraction of material properties based on thin-film wrinkling on scotch tape. Conventional FEM-based buckling simulation sometimes requires complex modeling techniques concerning mesh element manipulation or boundary conditions. The direct numerical simulation differs from FEM (finite element method)-based conventional two-step linear-nonlinear buckling simulation in that mechanical imperfections are directly applied into the elements of the simulation model. Hence, it can be performed in one step to find the wrinkling wavelength and amplitude, which are key parameters to extract the material mechanical properties. Moreover, the direct simulation can reduce simulation time and modeling complexity. Using the direct model, the effect of the number of imperfections on wrinkling characteristics was first studied, and then wrinkling wavelengths depending on the elastic moduli of the associated materials were prepared for the extraction of material properties. Thin-film wrinkling test patterns on scotch tape were fabricated using the transfer technique with low adhesion between metal films and the polyimide substrate. The material properties of the thin metal films were determined by comparing the measured wrinkling wavelengths and the proposed direct simulation results. By consequence, the elastic moduli of 300 nm thick gold film and 300 nm thick aluminum were determined as 250 GPa and 300 GPa, respectively.

2.
Ann Rheum Dis ; 73(2): 376-84, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23345601

ABSTRACT

OBJECTIVE: To assess the ability of avocado-soybean unsaponifiable-Expanscience (ASU-E) to slow radiographic progression in symptomatic hip osteoarthritis (OA). METHODS: Prospective, randomised, double blind, parallel group, placebo controlled 3 year trial. Patients with symptomatic (painful ≥1 year, Lequesne Index between 3 and 10) hip OA (American College of Rheumatology criteria) and a minimum joint space width (JSW) of the target hip between 1 and 4 mm on a pelvic radiograph were randomly assigned to 300 mg/day ASU-E or placebo. Standing pelvis, target hip anteroposterior (AP) and oblique views were taken annually. The primary outcome was JSW change at year 3, measured at the narrowest point on pelvic or target hip AP view (manual measure using a 0.1 mm graduated magnifying glass). The full analysis dataset (FAS) included all patients having at least two successive radiographs. An analysis of covariance Mixed Model for Repeated Measurements with Missing at Random (for missing data) was performed to compare adjusted 3 year JSW changes (primary outcome) and the percentages of 'progressors' (JSW loss≥0.5 mm) between groups. RESULTS: 399 patients were randomised (345 kept in the FAS), aged 62 (35-84) years, 54% women, mean body mass index 27 (SD 4) kg/m(2), mean symptom duration 4 (SD 5) years, 0-100 normalised Lequesne Index 30 (SD 9) and global pain visual analogue scale 37 (SD 23) mm. Mean baseline JSW was 2.8 (0.9) mm. There was no significant difference on mean JSW loss (-0.638 mm vs -0.672 mm, p=0.72, in the ASU-E and placebo groups, respectively) but there were 20% less progressors in the ASU-E than in the placebo group (40% vs 50%, respectively, p=0.040). No difference was observed on clinical outcomes. Safety was excellent. CONCLUSIONS: 3 year treatment with ASU-E reduces the percentage of JSW progressors, indicating a potential structure modifying effect in hip OA to be confirmed, and the clinical relevance requires further assessment.


Subject(s)
Osteoarthritis, Hip/drug therapy , Phytosterols/therapeutic use , Plant Extracts/therapeutic use , Vitamin E/therapeutic use , Adult , Aged , Aged, 80 and over , Analgesics/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Disease Progression , Double-Blind Method , Drug Administration Schedule , Drug Combinations , Female , Humans , Male , Middle Aged , Osteoarthritis, Hip/diagnostic imaging , Osteoarthritis, Hip/pathology , Pain Measurement/methods , Phytosterols/adverse effects , Phytotherapy/methods , Plant Extracts/adverse effects , Prospective Studies , Radiography , Severity of Illness Index , Treatment Outcome , Vitamin E/adverse effects
3.
J Rheumatol ; 38(8): 1765-9, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21807799

ABSTRACT

OBJECTIVE: To define pain and physical function cutpoints that would, coupled with structural severity, define a surrogate measure of "need for joint replacement surgery," for use as an outcome measure for potential structure-modifying interventions for osteoarthritis (OA). METHODS: New scores were developed for pain and physical function in knee and hip OA. A cross-sectional international study in 1909 patients was conducted to define data-driven cutpoints corresponding to the orthopedic surgeons' indication for joint replacement. A post hoc analysis of 8 randomized clinical trials (1379 patients) evaluated the prevalence and validity of cutpoints, among patients with symptomatic hip/knee OA. RESULTS: In the international cross-sectional study, there was substantial overlap in symptom levels between patients with and patients without indication for joint replacement; indeed, it was not possible to determine cutpoints for pain and function defining this indication. The post hoc analysis of trial data showed that the prevalence of cases that combined radiological progression, high level of pain, and high degree of function impairment was low (2%-12%). The most discriminatory cutpoint to define an indication for joint replacement was found to be [pain (0-100) + physical function (0-100) > 80]. CONCLUSION: These results do not support a specific level of pain or function that defines an indication for joint replacement. However, a tentative cutpoint for pain and physical function levels is proposed for further evaluation. Potentially, this symptom level, coupled with radiographic progression, could be used to define "nonresponders" to disease-modifying drugs in OA clinical trials.


Subject(s)
Arthroplasty, Replacement, Hip , Arthroplasty, Replacement, Knee , Osteoarthritis, Hip , Osteoarthritis, Knee , Cross-Sectional Studies , Disease Progression , Humans , International Cooperation , Osteoarthritis, Hip/physiopathology , Osteoarthritis, Hip/surgery , Osteoarthritis, Knee/physiopathology , Osteoarthritis, Knee/surgery , Outcome Assessment, Health Care/methods , Pain Measurement/methods , Randomized Controlled Trials as Topic , Severity of Illness Index , Surveys and Questionnaires , Treatment Outcome
4.
Clin Rheumatol ; 29(6): 659-70, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20179981

ABSTRACT

To investigate that a 6-month treatment with avocado soybean unsaponifiable (Piascledine 300 mg) once daily is as effective as with chondroitin sulfate 400 mg three times daily in femorotibial gonarthrosis, and also the carry-over effect for two more months is comparable. Patients were randomized (1:1) to the treatment groups. They received for 6 months 3 capsules chondroitin sulfate per day or one capsule of avocado soybean unsaponifiable (ASU) in a double-dummy technique. A 2-month post-treatment period followed to determine the carry-over effect. Primary efficacy criterion was the change of the WOMAC-index from study begin to end of treatment. Secondary criteria were the changes in Lequesne-index, pain on active movement and at rest, global assessment of efficacy. Three hundred sixty-four patients have been taken up into the trial. Three hundred sixty one patients were eligible for evaluation. One hundred eighty three received ASU 300 mg once daily, one hundred seventy eight chondroitin sulfate three times daily. The WOMAC-index decreased in both groups for approx. 50% to the end of therapy. During the post-treatment observation there was a further slight improvement. There was no statistical significant difference between the treatment groups during the entire observation. All other observed parameters showed the same pattern. The daily intake of rescue medication was reduced continuously. Overall efficacy has been rated excellent and good in more than 80% of the patients in both groups. Both drugs were safe and well tolerated. The first direct comparison between avocado soybean unsaponifiable 300 mg once daily and chondroitin sulfate three times daily reveiled no difference in efficacy or safety aspects between 1 capsule ASU 300 mg per day and 3 capsules chondroitin sulfate per day. It can be assumed that the once daily intake of ASU will lead to a better compliance in routine therapy.


Subject(s)
Chondroitin Sulfates/adverse effects , Osteoarthritis, Knee/drug therapy , Phytosterols/adverse effects , Plant Extracts/adverse effects , Vitamin E/adverse effects , Aged , Chondroitin Sulfates/therapeutic use , Double-Blind Method , Drug Administration Schedule , Drug Combinations , Female , Humans , Male , Middle Aged , Patient Compliance , Phytosterols/therapeutic use , Plant Extracts/therapeutic use , Prospective Studies , Severity of Illness Index , Treatment Outcome , Vitamin E/therapeutic use
5.
Joint Bone Spine ; 76(3): 268-72, 2009 May.
Article in English | MEDLINE | ID: mdl-19297230

ABSTRACT

OBJECTIVE: To develop a diagnostic score for knee osteoarthritis flare-ups and to evaluate its sensitivity and specificity. METHODS: We used two epidemiological databases built using the same methodology. One database was from a general-practice study and served to develop the score, whereas the other was from a rheumatology study and served to validate the score. Physicians determined the flare-up status of each patient. The rheumatologist diagnosis was the reference standard. Logistic regression was performed to identify factors significantly associated with having a flare-up. RESULTS: Of the 6085 patients in the general-practice database, 52.3% had a knee osteoarthritis flare-up. The score was built by assigning points to features that were present, with a weighting system based on the odds ratio of each feature for having a flare-up (0, feature absent; 1, morning stiffness for longer than 20 min; 2, pain causing nocturnal awakenings and knee effusion; 3, limping, joint swelling, and increased warmth over the knee). The score could range from 0 to 14. The receiver-operating characteristic curve showed that 7 was the best cutoff for diagnosing a flare-up. In the rheumatologist database, the numbers of patients having a flare-up were 274 (46.4%) based on the score and 270 (45.7%) based on the rheumatologist diagnosis. Sensitivity of the score was 87.0%, specificity 87.9%, positive predictive value 85.8%, and negative predictive value 89.0%. The Youden index was 0.75. CONCLUSION: A score equal to or greater than 7 points correlated well with a rheumatologist diagnosis of flare-up. Our score may constitute a valid objective criterion for standardizing the diagnosis of knee osteoarthritis flare-up, most notably when screening patients for inclusion in therapeutic trials.


Subject(s)
Osteoarthritis, Knee/diagnosis , Professional Practice , Rheumatology/methods , Aged , Cross-Sectional Studies , Databases, Factual , Female , Health Status , Humans , Knee Joint/physiopathology , Logistic Models , Male , Middle Aged , Osteoarthritis, Knee/physiopathology , Predictive Value of Tests , Professional Practice/statistics & numerical data , ROC Curve , Reproducibility of Results , Severity of Illness Index
6.
Joint Bone Spine ; 72(3): 235-40, 2005 May.
Article in English | MEDLINE | ID: mdl-15850995

ABSTRACT

UNLABELLED: The clinical burden of osteoarthritis (OA) is difficult to assess because of the substantial variability between patients. OBJECTIVE: Evaluate the human consequences of OA in patients. METHODS: In 2000, a nationwide survey was conducted among a sample of more than 5000 physicians (90.3% general practitioners and 9.7% rheumatologists), representative of French physicians. Each recruited the first two patients consulting for hip, knee, or hand OA after the survey began. The functional limitation rates were compared with those for age- and sex-matched controls obtained from the 1999 population-based national survey on disability (HID survey). RESULTS: Clinical and demographic information was obtained for 10,412 OA patients (mean-age 66.2 years, sex ratio F:M 1.96). The OA diagnosis was based on both clinical and radiographic findings for 84.5%. More than 80% of all patients reported limitations in their activities of daily living, either for basic tasks, leisure activities, or work. OA patients were substantially more limited than controls: the standardised limitation rate ratios (SLRR) were 6.0 (95% confidence interval: 5.9:6.1) for mobility outside the home, 2.1 (2.0:2.1) for house cleaning, 1.6 (1.5:1.8) for dressing oneself, and 1.6 (1.5:1.8) for sports. Of the 17.6% of OA patients and 17.5% of the controls still working, 64.4% and 14.3%, respectively, were limited in their job duties, for a SLRR of 4.5 (4.3:4.7). CONCLUSION: This study shows that OA-related disability has a significant impact on the retired as well as on those still involved in the labour market.


Subject(s)
Disability Evaluation , Osteoarthritis/physiopathology , Population Surveillance , Severity of Illness Index , Sickness Impact Profile , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , France/epidemiology , Humans , Male , Middle Aged , Osteoarthritis/epidemiology
7.
J Ethnopharmacol ; 94(1): 67-75, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15261965

ABSTRACT

The present study was conducted to evaluate in vitro and in vivo the antioxidant and anti-inflammatory properties of a cantaloupe melon (Cucumis melo LC., Cucurbitaceae) extract (CME) selected for its high superoxide dismutase activity. Peritoneal macrophages were pre-activated in vitro with 300 IU of interferon-gamma (IFN-gamma) and were then challenged in culture with IgGl/anti-IgG1 immune complexes (IgG1IC) in presence of various CME extracts. The subsequent production of free radicals (superoxide anion, nitric oxide, and peroxynitrite) and of pro-(TNF-alpha) and anti-(IL-10) inflammatory cytokines was evaluated. The CME inhibited in a dose-dependent manner the production of superoxide anion with a maximal effect at 100 microg/ml. This inhibitory effect of CME appeared to be closely linked to the SOD activity because it was dramatically decreased after heat inactivation of the SOD activity (HI-CME). In addition, the CME inhibited the production of peroxynitrite strengthening the antioxidant properties of this CME rich in SOD activity. The production of the pro- and anti-inflammatory cytokines, namely TNF-alpha and IL-10, being conditioned by the redox status of macrophages we also evaluated the effect of CME and HI-CME on the IgG1IC-induced cytokine production. When the SOD activity was present in the CME it promoted the IgG1IC-induced production of IL-10 instead of TNF-alpha. These data demonstrated that, in addition to its antioxidant properties, the anti-inflammatory properties of the CME extract were principally related to its capacity to induce the production of IL-10 by peritoneal macrophages. The particular properties of wheat gliadin (Triticum vulgare, Poaceae) for the oral delivery of functional proteins led us to test it in a new nutraceutical formula based on its combination with the CME thus monitoring the SOD activity release during the gastro-intestinal digestive process. In these experiments C57BL/6 mice were supplemented orally everyday during 28 days with: (1) the placebo, (2) the CME extract alone, (3) the gliadin, (4) the CME/gliadin combination, or (5) the HI-CME/gliadin combination (SOD inactivated). At the end of the supplementation period all the animals were injected intra-peritoneal (i.p.) with the pro-inflammatory cytokine IFN-gamma (300 IU) and peritoneal macrophages were harvested 24 h after to test their capacities to produce free radicals, TNF-alpha and IL-10 after triggering with IgG1IC. We demonstrated that animals supplemented during 28 days with the CME/gliadin combination were protected against the pro-inflammatory properties of IFN-gamma while the other products were inefficient. These data did not only indicate that the SOD activity is important for the antioxidant and anti-inflammatory properties of the CME extract, but also demonstrated that when the SOD activity is preserved during the digestive process by its combination with wheat gliadin it is possible to elicit in vivo the pharmacological effects of this antioxidant enzyme.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Cucumis melo , Superoxide Dismutase/pharmacology , Animals , Cells, Cultured , Dose-Response Relationship, Drug , Free Radicals/metabolism , Gliadin/pharmacology , Interleukin-10/biosynthesis , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Mice , Mice, Inbred C57BL , Plant Extracts/pharmacology , Protein Precursors/antagonists & inhibitors , Tumor Necrosis Factor-alpha/antagonists & inhibitors
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