ArthroRad trial: multicentric prospective and randomized single-blinded trial on the effect of low-dose radiotherapy for painful osteoarthritis depending on the dose-results after 3 months' follow-up

Purpose Randomized comparison of the effect of radiotherapy on painful osteoarthritis (OA) applying a standard-dose vs. a very-low-dose regime Patients and methods Patients with OA of the hand and knee joints were included. Further inclusion criteria: symptoms for more than 3 months, favorable general health status, age above 40 years. Patients with prior local radiotherapy, trauma, rheumatoid arthritis, or vascular diseases were excluded. After randomization (every joint was randomized separately), the following protocols were applied: standard arm: total dose 3.0 Gy, single fractions of 0.5 Gy twice weekly; experimental arm: total dose 0.3 Gy, single fractions of 0.05 Gy twice weekly. The dosage was not known to the patients. The patients were examined 3 and 12 months after radiotherapy. Scores like VAS (visual analogue scale), KOOS-SF (the knee injugy and osteoarthritis outcome score), SF-SACRAH (short form score for the assessment and quantification of chronic rheumatic affections of the hands), and SF-12 (short form 12) were used. Results A total of 64 knees and 172 hands were randomized. 3.0 Gy was applied to 87 hands and 34 knees, 0.3 Gy was given to 85 hands and 30 knees. After 3 months, we observed good pain relief after 3 Gy and after 0.3 Gy, there was no statistically significant difference. Side effects were not recorded. The trial was closed prematurely due to slow recruitment. Conclusion We found favorable pain relief and a limited response in the functional and quality of life scores in both arms. The effect of low doses such as 0.3 Gy on pain is widely unknown. Further trials are necessary to compare a conventional dose to placebo and to further explore the effect of low doses on inflammatory disorders

Electric Field Control of Spin Transport

Spintronics is an approach to electronics in which the spin of the electrons is exploited to control the electric resistance R of devices. One basic building block is the spin-valve, which is formed if two ferromagnetic electrodes are separated by a thin tunneling barrier. In such devices, R depends on the orientation of the magnetisation of the electrodes. It is usually larger in the antiparallel than in the parallel configuration. The relative difference of R, the so-called magneto-resistance (MR), is then positive. Common devices, such as the giant magneto-resistance sensor used in reading heads of hard disks, are based on this phenomenon. The MR may become anomalous (negative), if the transmission probability of electrons through the device is spin or energy dependent. This offers a route to the realisation of gate-tunable MR devices, because transmission probabilities can readily be tuned in many devices with an electrical gate signal. Such devices have, however, been elusive so far. We report here on a pronounced gate-field controlled MR in devices made from carbon nanotubes with ferromagnetic contacts. Both the amplitude and the sign of the MR are tunable with the gate voltage in a predictable manner. We emphasise that this spin-field effect is not restricted to carbon nanotubes but constitutes a generic effect which can in principle be exploited in all resonant tunneling devices.Comment: 22 pages, 5 figure

The relationships of markers of cholesterol homeostasis with carotid intima-media thickness

Background: The relationship of cholesterol homeostasis and carotid intima-media thickness (cIMT) is unknown. To address this, we assessed markers of cholesterol homeostasis (serum plant sterols and cholesterol precursor concentrations as surrogate measures of cholesterol absorption and synthesis, respectively) and cIMT in a middle-aged, statin-naive population. Methods: In this prospective study of primary prevention cIMT was measured by ultrasound in 583 hospital employees aged 25—60 years without prevalent cardiovascular disease or lipid-modifying medication. The serum concentrations of plant sterols (as markers of cholesterol absorption) were measured by gas-liquid chromatography. Lathosterol serum concentrations were quantitated to assess hepatic cholesterol synthesis. Results: cIMT correlated positively with serum cholesterol (r = 0.22, P,0.0005) and lathosterol-to-cholesterol (r = 0.18, P,0.001). In contrast, plant sterols, as markers of cholesterol absorption, showed a weak negative correlation to cIMT measurements (r =20.18; P,0.001 for campesterol-to-cholesterol). Stratifying subjects by serum sterol levels, we found that cIMT increased continuously over quintiles of serum cholesterol (P,0.0005) and was positively associated to serum lathosterol-to-cholesterol levels (P=0.007), on the other hand, plant sterol levels showed a weak negative association to cIMT (P,0.001 for campesterol-to-cholesterol). Conclusions: In this population without prevalent cardiovascular diseases or lipid-modifying medication, markers of increased endogenous cholesterol synthesis correlated positively with cIMT, while markers of cholesterol absorption showed a weakly negative correlation. These data suggest that not only total serum cholesterol levels but also differences in cholesterol homeostasis are associated with cIMT

Accessing the quantum world through electronic transport in carbon nanotubes

In this thesis we will focus on (a) superconducting electrodes attached to carbon nanotube quantum dots in order to study the effects of superconducting correlations on quantum systems and (b) local gate control of carbon nanotubes in order to define and control double quantum dot systems in carbon nanotubes. As it turns out, local gates are an important tool for increasing the control over quantum states in nanotubes. The thesis is structured as follows: • Chapter 1 gives a brief introduction to the chemical and electronic properties of carbon nanotubes and the experimental procedures necessary for manufacturing electrical devices with single carbon nanotubes. • In Chapter 2 selected topics of charge transport in mesoscopic systems, such as single and coupled quantum dots, are reviewed. • In Chapter 3 we present electrical transport measurements through a carbon nanotube coupled to a normal and a superconducting lead - a test system for the exploration of the nature of many-particle correlations. • Chapter 4 describes how to achieve local gate control over semiconducting carbon nanotubes by adding top-gate electrodes. • In Chapter 5 double quantum dots are defined and controlled inside a carbon nanotube. The system allows for the observation of molecular states induced by a large tunnel coupling of the dots; an artificial molecule is defined inside a real one

ArthroRad trial: randomized multicenter single-blinded trial on the effect of low-dose radiotherapy for painful osteoarthritis-final results after 12-month follow-up

Objective Updated report about the randomized comparison of the effect of radiotherapy on painful osteoarthritis (OA) applying a standard dose vs. a very low dose regime after a follow-up of 1 year. Patients and methods Patients presenting with OA of the hand/finger and knee joints were included. After randomization (every joint region was randomized separately) the following protocols were applied: (a) standard arm: total dose 3.0 Gy, single fractions of 0.5 Gy twice a week; (b) experimental arm: total dose 0.3 Gy, single fractions of 0.05 Gy twice a week. The dosage was blinded for the patients. For evaluation the scores after 1-year visual analog scale (VAS), Knee Injury and Osteoarthritis Outcome Score–Short Form (KOOS-PS), Short Form Score for the Assessment and Quantification of Chronic Rheumatic Affections of the Hands (SF-SACRAH) and 12-item Short-Form Health Survey (SF-12) were used (for further details: see [1]). Results The standard dose was applied to 77 hands and 33 knees, the experimental dose was given to 81 hands and 30 knees. After 12 months, the data of 128 hands and 45 knees were available for evaluation. Even after this long time, we observed a favorable response of pain to radiotherapy in both trial arms; however, there were no reasonable statistically significant differences between both arms concerning pain, functional, and quality of life scores. Side effects did not occur. The only prognostic factor was the pain level before radiotherapy. Conclusions We found a favorable pain relief and a limited response in the functional and quality of life scores in both treatment arms. The possible effect of low doses such as 0.3 Gy on pain is widely unknown

Intima-media thickness measurements in relation to quintiles of serum cholesterol, lathosterol, campesterol and sitosterol.

<p>A: Intima-media thickness measurements in relation to quintiles of serum cholesterol concentration (<i>P<0.0005</i>). Values are mean +/− SEM. B: Intima-media thickness measurements in relation to quintiles of serum lathosterol concentration (<i>P<0.0005</i>). Values are mean +/− SEM. C: Intima-media thickness measurements in relation to quintiles of serum campesterol concentration. Values are mean +/− SEM. D: Intima-media thickness measurements in relation to quintiles of serum sitosterol concentration. Values are mean +/− SEM.</p

Intima-media thickness measurements in relation to quintiles of serum lathosterol-to-cholesterol, campesterol-to-cholesterol and sitosterol-to-cholesterol.

<p>A: Intima-media thickness measurements in relation to quintiles of lathosterol-to-cholesterol (<i>P = 0.007</i>). Values are mean +/− SEM. B: Intima-media thickness measurements in relation to quintiles of campesterol-to-cholesterol (<i>P<0.001</i>). Values are mean +/− SEM. C: Intima-media thickness measurements in relation to quintiles of sitosterol-to-cholesterol (<i>P<0.001</i>). Values are mean +/− SEM.</p

Patient Characteristics.

<p>Patient Characteristics.</p

Multivariable regression analysis of cholesterol and markers of cholesterol metabolism in relation to cIMT.

<p>B: standardized regression coefficient; <i>P</i>: level of significance. All values have been log-transformed prior to analysis.</p><p>LDL-c: low density lipoprotein cholesterol; HDL-c: high density lipoprotein cholesterol; BP: blood pressure; BMI: body mass index; TG: triglycerides.</p