| 1. |
- Bode, Felix J., et al.
(författare)
-
Sex differences in a transgenic rat model of Huntington's disease: decreased 17 beta-estradiol levels correlate with reduced numbers of DARPP32(+) neurons in males
- 2008
-
Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 17:17, s. 2595-2609
-
Tidskriftsartikel (refereegranskat)abstract
- Recent clinical studies have highlighted that female sex hormones represent potential neuroprotective mediators against damage caused by acute and chronic brain diseases. This evidence has been confirmed by experimental studies documenting the protective role of female sex hormones both in vitro and in vivo, although these studies did not specifically focus on Huntington's disease (HD). We therefore investigated the onset and course of HD in female and male transgenic (tg) HD (CAG(n51)) and control rats across age and focused on three aspects: (i) behavioral and physiological alterations (energy expenditure, home-cage activity, emotional disturbance and motor dysfunction), (ii) morphological markers (numbers and characteristics of striatal DARPP32(+) medium-sized spiny neurons (MSNs) and dopamine receptor autoradiography) and (iii) peripheral sex hormone levels as well as striatal estrogen receptor expression. Independent of their sex, tgHD rats exhibited increased levels of food intake, elevated home-cage activity scores and anxiolytic-like behavior, whereas only males showed an impairment of motor function. In line with the latter finding, loss and atrophy of DARPP32(+) MSNs were apparent only in male tgHD rats. This result was associated with a decreased striatal dopamine D1 receptor density and lower plasma levels of 17 beta-estradiol at the age of 14 months. As DARPP32(+) MSNs expressed both alpha-and beta-estrogen receptors and showed a correlation between cell numbers and 17 beta-estradiol levels, our findings suggest sex-related differences in the HD phenotype pointing to a substantial neuroprotective effect of sex hormones and opening new perspectives on the therapy of HD.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Bauer, Florian, 1975-, et al.
(författare)
-
Evaluation of a Micro-Channel Plate PMT in PET
- 2006
-
Ingår i: Nuclear Science Symposium Conference Record, 2006, IEEE. - 1424405602 ; , s. 2503-2505
-
Konferensbidrag (refereegranskat)abstract
- The focus of this paper is the evaluation of micro-channel plate PMTs for PET detectors. Several properties of MCPs make them interesting for PET applications, such as fast time response, high spatial resolution, compact size, low susceptibility to magnetic fields, high gain and low power consumption. The preliminary tests in this paper are performed with the 51 mm times 51 mm square Burle 85011-501 assembly with 64 anodes (8 times 8). A new version of this MCP will be examined for the full paper. Initial measurements have been performed with a pulsed LASER (Hamamatsu Picosecond Light Pulser PLP-10 with M8903 Laser diode head). The engineering sample of the 85011 exhibited a time resolution of 26 ps. Further measurements will be performed, such as transit time measurements and timing measurements with scintillators. Single-photon timing measurements were presented earlier in [Ref. 1], from the old version as well as the suitability of the device in Cherenkov detectors in [Ref. 2]. For the full paper it is also planned to develop a circuit which allows lossless splitting of the anode signal.
|
|
| 5. |
- Bauer, Margit, et al.
(författare)
-
Assessment of the in vivo biomechanical properties of the human uterine cervix in pregnancy using the aspiration test A feasibility study
- 2009
-
Ingår i: European Journal of Obstetrics, Gynecology, and Reproductive Biology. - : Elsevier BV. - 0301-2115 .- 1872-7654. ; 144, s. S77-S81
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To date no diagnostic tool is yet available to objectively assess the in vivo biomechanical properties of the uterine cervix during gestation. Methods: We show the first clinical application of an aspiration device to assess the in vivo biomechanical properties of the cervix in pregnancy with the aim to describe the physiological biomechanical changes throughout gestation in order to eventually detect pregnant women at risk for cervical insufficiency (CI). Results: Out of 15 aspiration measurements, 12 produced valid results. The stiffness values were in the range between 0.013 and 0.068 bar/mm. The results showed a good reproducibility of the aspiration test. In our previous test series on non-pregnant cervices our repetitive measurements showed a standard deviation of > 20% compared to <+/- 10% to our data on pregnant cervices. Stiffness values are decreasing with gestational age which indicates a progressive softening of cervical tissue towards the end of pregnancy. Three pregnant women had two subsequent measurements within a time interval of four weeks. Decreasing stiffness values in the range of 20% were recorded. Discussion: This preliminary study on the clinical practicability of aspiration tests showed promising results in terms of reproducibility (reliability) and clinical use (feasibility). Ongoing studies will provide further insights on its usefulness in clinical practice and in the detection of substantial changes of the cervix in pregnancy indicative for threatened preterm birth or cervical insufficiency.
|
|
| 6. |
|
|
| 7. |
- Bode, Felix J., et al.
(författare)
-
Increased numbers of motor activity peaks during light cycle are associated with reductions in adrenergic alpha(2)-receptor levels in a transgenic Huntington's disease rat model
- 2009
-
Ingår i: Behavioural Brain Research. - : Elsevier BV. - 0166-4328. ; 205:1, s. 175-182
-
Tidskriftsartikel (refereegranskat)abstract
- Huntington's disease (HID) is a neurodegenerative disorder caused by a CAG repeat expansion in the HD gene. Besides psychiatric, motor and cognitive symptoms, HD patients suffer from sleep disturbances. In order to screen a rat model transgenic for HD (tgHD rats) for sleep-wake cycle dysregulation, we monitored their circadian activity peaks in the present study. TgHD rats of both sexes showed hyperactivity during the dark cycle and more frequent light cycle activity peaks indicative for a disturbed sleep-wake cycle. Focusing on males at the age of 4 and 14 months, analyses of receptor levels in the hypothalamus and the basal forebrain revealed that 5-HT2A- and adrenergic alpha(2)-receptor densities in these regions were significantly altered in tgHD rats compared to their wild-type littermates. Adrenergic receptor densities correlated negatively with the light cycle hyperactivity peaks at later stages of the disease in male tgHD rats. Furthermore, reduced leptin levels, a feature associated with circadian misalignment, were present. Our study demonstrates that the male tgHD rat is a suitable model to investigate HD associated sleep alterations. Further studies are warranted to elucidate the role of adrenergic- and 5-HT2A- receptors as therapeutic targets for dysregulation of the circadian activity in HD. (C) 2009 Elsevier B.V. All rights reserved.
|
|
| 8. |
- Heijl, Anders, et al.
(författare)
-
Nordic research in ophthalmology.
- 2005
-
Ingår i: Acta ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 83:3, s. 278-88
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Nordic ophthalmologists and vision scientists are active in many fields of eye research. This is most evident at the biannual Nordic Congress of Ophthalmology, most recently held in Malmö in June 2004. The authors here review some of the research in vision and ophthalmology presented at this meeting or published recently by Nordic scientists. This paper does not represent a comprehensive review of all Nordic research in the field, but attempts to give an overview of some of the activities underway in eye research in this part of the world.
|
|
| 9. |
- Kumar, Ravhi S., et al.
(författare)
-
Pressure-induced valence change in YbAl3 : A combined high-pressure inelastic x-ray scattering and theoretical investigation
- 2008
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 78:7, s. 075117-
-
Tidskriftsartikel (refereegranskat)abstract
- High-resolution x-ray-absorption (XAS) experiments in the partial fluorescence yield mode (PFY) and resonant inelastic x-ray emission (RXES) measurements were performed on the intermediate-valence compound YbAl3 under pressure of up to 38 GPa. The results of the YbAl3 PFY-XAS and RXES studies show that the valence of Yb increases smoothly from 2.75 at ambient pressure to 2.93 at 38 GPa. In situ angle-dispersive synchrotron high-pressure x-ray-diffraction experiments carried out using a diamond cell at room temperature show that the ambient pressure cubic phase is stable up to 40 GPa. The results obtained from self-interaction corrected local spin density-functional calculations to understand the pressure effect on the Yb valence and compressibility are in good agreement with the experimental results.
|
|
| 10. |
|
|
