UVB-induced inflammation gives increased d-dopachrome tautomerase activity in blister fluid which correlates with macrophage migration inhibitory factor.

UVB light was used to induce an experimental inflammation in normal human skin in order to investigate its correlation with the activity of the newly described enzyme d-dopachrome tautomerase (DDT) in the fluid of experimental blisters. Macrophage migration inhibitory factor (MIF) activity was determined as a closely related marker of inflammation. DDT and MIF activities were demonstrated in blister fluids in all 10 healthy subjects. All but one of these subjects showed increased activity of DDT and MIF after three minimal erythemal doses (MED) of UVB. The mean activity of DDT increased approximately twofold and the mean activity of MIF also increased twofold after UVB in our experimental model. We found a strong correlation between DDT and MIF activities. The presence of DDT in epidermis and its increase at UV irradiation was confirmed by immunohistochemical studies. In this study, DDT is for the first time demonstrated in the skin. It is also the first time DDT can be related to inflammation, and its covariation with MIF strengthens this observation

The effects of an enhanced UV-B radiation on a sub-arctic heath ecosystem

To investigate the effects of increased UV-B radiation on a natural subarctic ecosystem a field irradiation experiment was established at Abisko, northern Sweden. The vegetation in the plots consists of a dwarf shrub layer with mosses and lichens beneath. Many response variables of the vegetation and soil are measured in these plots, e.g. photosynthesis, growth, phenology, changes in species composition and decomposition. This paper describes the methods used and some initial results. Decomposition was imparied by enhanced UV-B radiation. UV-B directly affected decomposition processes and also affected them indirectly by altering the tissue chemistry of leaves. The annual growth of the dwarf shrubs was lower under enhanced UV-B. This was more pronounced in evergreen than in deciduous species. Leaf thickness of the dwarf shrubs was changed by UV-B. The leaves of the evergreen Vaccinium vitis-idaea grew thicker, while those of the two deciduous species V. myrtillus and V. uliginosum grew thinner. In the moss Hylocomium splendens, the phenological development was accelerated under enhanced UV-B radiation. Its growth (number of primary branches, length and dry weight) also increased

Late magnetic resonance imaging related to neurobehavioral functioning after aneurysmal subarachnoid hemorrhage

Twenty patients who underwent early aneurysm surgery--that is, surgery within 72 hours after rupture--underwent further follow-up examination including magnetic resonance imaging (MRI) of the brain and a comprehensive neuropsychological assessment. Significant statistical correlation between tissue loss as seen on a late MRI scan and neurobehavioral deficits could not be established. Among 9 patients with no tissue loss seen on MRI, 3 exhibited substantial cognitive dysfunction and 6 had mild impairment. Three patients showed minor but corresponding tissue loss and deficits. In 3 patients with pronounced pathological indications on MRI, evidence of cognitive dysfunction was absent in 2, and 1 patient showed substantial impairment. The remaining 5 individuals displayed moderate pathological indications on MRI, with no obvious correspondence to cognitive functioning. In 7 patients, small white matter lesions, probably silent infarcts not seen on computed tomographic scan, were discovered on MRI. There was a clear relationship between arterial hypertension prior to aneurysm rupture and the extent of tissue loss seen on MRI. Absence of pathological findings on MRI scan did not exclude cognitive malfunctioning, and vice-versa

The problem of ozone depletion in northern Europe

Ozone in the atmosphere, mainly in the stratosphere, absorbs most of the ultraviolet-B (wavelength 280-315 nm) radiation from the sun, which can destroy DNA and other biologically important molecules and, thereby, damage living organisms. Due to the pollution of the atmosphere by humans, the ozone layer is presently being depleted, more rapidly at higher latitudes than at lower, and more rapidly over Scandinavia than over most geographical regions at corresponding latitudes. Ultraviolet-B radiation is generally more intense in mountain regions than at sea level. We have experiments in progress in which we simulate the effects of further ozone depletion on terrestrial ecosystems (mountain heaths, bogs, tundra) by irradiating them with artificial ultraviolet-B radiation. Effects on the growth of dwarf-shrubs and mosses and on plant litter decomposition are described

Multicenter Analysis of Endovascular Aortic Arch In Situ Stent-Graft Fenestrations for Aortic Arch Pathologies

Background: In situ fenestration of aortic stent grafts for treatment of aortic arch aneurysms is a new option for endovascular aortic arch repair. So far, only few reports have shown perioperative and short-term results of in situ fenestrations for aortic arch diseases. We present the multicenter experience with the aortic arch in situ fenestration technique documented in the AARCHIF registry for treatment of aortic arch aneurysms or localized type A aortic dissections and analyzed perioperative outcome and midterm follow-up. Methods: Patients with aortic arch pathologies treated by aortic arch in situ fenestration with proximal stent graft landing in aortic arch Ishimura zones 0 and 1 were included in the registry. Stent-graft in situ fenestrations were created using needles or radiofrequency or laser catheters and completed by implantation of covered connecting stent grafts. Single in situ fenestrations for the left subclavian artery (LSA) were excluded. Results: Between 06/2009 and 03/2017, twenty-five patients were treated by in situ stent-graft fenestrations for aortic arch pathologies at 9 institutions in 7 different countries, 3 of them as bailout procedures for stent-graft malplacement. In situ fenestrations were performed for the bra-chiocephalic trunk (n = 20), the left common carotid artery (n = 21) and the LSA (n = 9). Technical success for intended in situ fenestrations was 94.0% (47/50), with additional supraaortic bypass procedures performed in 14 patients. Perioperative mortality occurred in 1 (4.0%) patient, treated as a bailout procedure and 3 (12.0%) perioperative strokes were observed. One proximal aortic stent-graft nonalignment and 4 type III endoleaks, 2 early and 2 late, required reeintervention. During follow-up (1-118 months), the diameter of aortic arch aneurysms decreased from 61.5 +/- 4.1 mm to 48.4 +/- 3.2 mm (P = 0.02) and, so far, 6 patients died from diseases unrelated to their aortic arch pathologies with a mean survival time of 79.5 months and 3 endovascular reinterventions for distal aortic expansion were performed. Cerebrovascular event (n = 4) was the most relevant prognostic factor for mortality during midterm follow-up (P = 0.003). Conclusions: The aortic arch in situ fenestration technique for endovascular aortic arch repair seems to be valuable treatment option for selected patients, although initial consideration of other treatment options is mandatory. Data about long-term durability are required

Effects of ozone depletion and increased ultraviolet-B radiation on northern vegetation

The stratospheric ozone layer has been depleted at high and mid-latitudes as a consequence of man's pollution of the atmosphere, and this results in increasing ultraviolet-B radiation at ground level. We investigate the effects of further radiation increases on plants and ecosystems by irradiating natural sub-Arctic and Arctic vegetation with artificial W-B radiation in field experiments extending over several years. Our experimental sites are located at Abisko, in northern Sweden (68 degrees N), and Adventdalen, on the island of Spitsbergen (78 degrees N). Additional UV-B induced interspecific differences in plant response in terms of reduced (or, in one case, increased) growth, changed morphology and changed pigment content. In some cases effects seem to be accumulated from one year to another. Plant litter decomposition is retarded. We are also studying how UV-B enhancement may affect the interaction between species. In some experiments we combine UV-B enhancement with changes in other factors: carbon dioxide concentration, water availability, and temperature. In some cases the effect of radiation enhancement is modified, or even reversed, by such changes. Over a four year period we did not find any significant radiation induced change in species composition, but based on the effects on individual plant species, such changes can be expected to take place over a longer time

Stratospheric ozone depletion: high arctic tundra plant growth on Svalbard is not affected by enhanced UV-B after 7 years of UV-B supplementation in the field.

The response of tundra plants to enhanced UV-B radiation simulating 15 and 30% ozone depletion was studied at two high arctic sites (Isdammen and Adventdalen, 78 degrees N, Svalbard).The set-up of the UV-B supplementation systems is described, consisting of large and small UV lamp arrays, installed in 1996 and 2002. After 7 years of exposure to enhanced UV-B radiation, plant cover, density, morphological (leaf fresh and dry weight, leaf thickness, leaf area, reproductive and ecophysiological parameters leaf UV-B absorbance, leaf phenolic content, leaf water content) were not affected by enhanced UV-B radiation. DNA damage in the leaves was not increased with enhanced UV-B in Salix polaris and Cassiope tetragona. DNA damage in Salix polaris leaves was higher than in leaves of C. tetragona. The length of male gametophyte moss plants of Polytrichum hyperboreum was reduced with elevated UV-B as well as the number of Pedicularis hirsuta plants per plot, but the inflorescence length of Bistorta vivipara was not significantly affected. We discuss the possible causes of tolerance of tundra plants to UV-B (absence of response to enhanced UV-B) in terms of methodology (supplementation versus exclusion), ecophysiological adaptations to UV-B and the biogeographical history of polar plants