Metabolomics of Synovial Fluid and Infrapatellar Fat Pad in Patients with Osteoarthritis or Rheumatoid Arthritis

Inflammation - Osteoarthritis (OA) and autoimmune-driven rheumatoid arthritis (RA) are inflammatory joint diseases with complex and insufficiently understood pathogeneses. Our objective was to...     

Assessing Rationality in Discrete Choice Experiments in Health: An Investigation into the Use of Dominance Tests

Background

Dominance tests are often applied to test for the rationality in the choice behavior of participants in discrete choice experiments (DCEs).

Effects of cellular phone use on ear canal temperature measured by NTC thermistors

The earlier studies using phantom models and human subjects concerning warming effects during cellular phone use have been controversial, partly because radiofrequency (RF) exposures have been variable. In this randomized, double-blind, placebo-controlled crossover trial, 30 healthy subjects were submitted to 900 MHz (2W) and 1800 MHz (1W) cellular phone RF exposure, and to sham exposure in separate study sessions. Temperature signals were recorded continuously in both ear canals before, during and after the 35-min RF exposure and the 35-min sham exposure sessions. Temperature was measured by using small-sized NTC thermistors placed in the ear canals through disposable ear plugs. The mean temperature changes were determined during a set cardiovascular autonomic function studies: during a 5-min controlled breathing test, during a 5-min spontaneous breathing test, during 7-min head-up tilting, 1-min before, during and after two consecutive Valsalva manoeuvres and during a deep breathing test. Temperatures in the exposed ear were significantly higher during RF exposures compared with sham exposure in both 900 and 1800 MHz studies with maximum differences of 1 x 2 +/- 0 x 5 degrees C (900 MHz exposure) and 1 x 3 +/- 0 x 7 degrees C (1800 MHz exposure). Temperatures in the RF-exposed ear were also significantly higher during the postexposure period compared with post-sham exposure period with maximum differences of 0 x 6 +/- 0 x 3 degrees C for 900 MHz and 0 x 5 +/- 0 x 5 degrees C for 1800 MHz. The results of this study suggest that RF exposure to a cellular phone, either using 900 or 1800 MHz with their maximal allowed antenna powers, increases the temperature in the ear canal. The reason for the ear canal temperature rising is a consequence of mobile phone battery warming during maximal antenna power use. The earlier published articles do not indicate that temperature rising in the ear canal has any significant contribution from the RF fields emitted from mobile phones.     

Effect of 12‐month statin therapy on antioxidant potential of LDL and serum antioxidant vitamin concentrations

BACKGROUND. Statins are known to cause short‐term reduction in serum lipid‐soluble antioxidant concentrations, but their long‐term effects are not known.

AIM: We randomised 104 subjects with CHD and hypercholesterolaemia to receive either atorvastatin or simvastatin treatment for 52 weeks and measured the antioxidant potential of LDL and serum antioxidant vitamin concentrations.

METHOD: Initial daily dose for both statins was 20?mg.

RESULTS: LDL antioxidant capacity and serum α‐tocopherol, γ‐tocopherol and β‐carotene concentrations decreased by 22%–35% with both statins during the first 12 weeks' therapy ( P ?<?0.01 for all). After 52 weeks' therapy, the concentrations of serum γ‐tocopherol in the simvastatin group and serum β‐carotene in both treatment groups returned to baseline levels, while the concentrations of serum γ‐tocopherol in the atorvastatin group and LDL antioxidant capacity and serum α‐tocopherol in both treatment groups remained reduced ( P ?<?0.001 for all). The LDL antioxidant capacity:LDL‐cholesterol and the serum α‐tocopherol:LDL‐cholesterol ratios were significantly elevated with both statins after 12 and 52 weeks ( P ?<?0.001 for all). Statistically significant increases were also observed for corresponding ratios of the less abundant vitamins γ‐tocopherol and β‐carotene.

CONLUSIONS: Some of the decreases in serum lipid soluble antioxidant vitamins reported in short‐term statin interventions may become attenuated when therapy continues longer. The relative antioxidant capacity of LDL particles increased during the 52‐week treatment, suggesting that the oxidation resistance of LDL particles did not become impaired and that their atherogenicity did not increase.     

Longitudinal rotating frame relaxation time measurements in infarcted mouse myocardium in vivo

Longitudinal relaxation time in the rotating frame (T_1ρ) was measured using continuous wave irradiation in normal and infarcted mouse myocardium in vivo. Significant increase in T_1ρ was found after 7 days of infarction when compared with reference myocardium or in myocardium before infarction. Cine MRI and histology were performed to verify the severity of infarction. The time course of T_1ρ in the infarct fits better with granulation and scar tissue formation than necrosis and edema. The results of the study show that T_1ρ could potentially be a noninvasive quantitative marker for tissue remodeling after ischemic damage. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.     

The effect of decompressive surgery on lumbar paraspinal and biceps brachii muscle function and movement perception in lumbar spinal stenosis: a 2-year follow-up

Purpose

Chronic low back pain and lumbar spinal stenosis (LSS) seem to deteriorate lumbar muscle function and proprioception but the effect of surgery on them remains unclear. This study evaluates the effect of decompressive surgery on lumbar movement perception and paraspinal and biceps brachii (BB) muscle responses during sudden upper limb loading in LSS.

Methods

Low back and radicular pain intensity (VAS) and Oswestry Disability Index (ODI) were measured together with lumbar proprioception and paraspinal and BB muscle responses prior to and 3 and 24 months after surgery in 30 LSS patients. Lumbar proprioception was assessed by a previously validated motorized trunk rotation unit and muscle responses for sudden upper limb loading by surface EMG.

Results

Lumbar perception threshold improved after surgery during 3-month follow-up (from 4.6° to 3.1°, P = 0.015) but tend to deteriorate again during 24 months (4.0°, P = 0.227). Preparatory paraspinal and BB muscle responses prior to sudden load as well as paraspinal muscle activation latencies after the load remained unchanged.

Conclusion

Impaired lumbar proprioception seems to improve shortly after decompressive surgery but tends to deteriorate again with longer follow-up despite the sustaining favorable clinical outcome. The surgery did not affect either the feed-forward or the feed-back muscle function, which indicates that the abnormal muscle activity in LSS is at least partly irreversible.