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Studies have revealed that Ixodes ricinus (Acari: Ixodidae) have become more abundant and their geographical distribution extended northwards in some Nordic countries during the past few decades. However, ecological data of tick populations in Finland are sparse. In the current study, I. ricinus abundance, seasonal questing activity, and their Borrelia spp. and tick-borne encephalitis virus (TBEV) prevalence were evaluated in a Lyme borreliosis endemic area in Southwest Finland, Seili Island, where a previous study mapping tick densities was conducted 12 years earlier. A total of 1940 ticks were collected from five different biotopes by cloth dragging during May-September 2012. The overall tick density observed was 5.2 ticks/100m(2) for nymphs and adults. Seasonal questing activity of ticks differed between biotopes and life stages: bimodal occurrences were observed especially for nymphal and adult ticks in forested biotopes, while larvae in pastures exhibited mostly unimodal occurrence. Prevalence of Borrelia and TBEV in ticks was evaluated using conventional and real-time PCR. All samples were negative for TBEV. Borrelia prevalence was 25.0% for adults (n=44) and the minimum infection rate (MIR) 5.6% for pooled nymph samples (191 samples, 1-14 individuals per sample; 30/191 positive). No Borrelia were detected in pooled larval samples (63 samples, 1-139 individuals per sample). Five species of Borrelia were identified from the samples: B. afzelii, B. burgdorferi s.s., B. garinii, B. valaisiana and B. miyamotoi. In Finland, B. valaisiana and B. miyamotoi have previously been reported from the Åland Islands but not from the mainland or inner archipelago. The results of the present study suggest an increase in I. ricinus abundance on the island., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Oribatid mites have often been used as indicators of the degree of environmental pollution but few studies have assessed the effects of pollution at individual level. One possible indicator of environmental stress at individual level is structural malformations of exoskeleton. We studied whether a number of leg deformities in soil oribatid mites could be used as an indicator of the degree of heavy metal pollution or acidity in nature. For this purpose we collected soil samples in a well known pollution gradient of a Finnish Cu-Ni smelter. Heavy metals are common pollutants in the area. Ten focal oribatid species were inspected under microscope for deformations in their legs (missing, broken or deformed leg). Of the focal species only one (Chamobates cuspidatus) showed an increasing trend along the pollution gradient in the proportion of leg abnormalities but there were clear differences in proportions among species. We consider that leg deformities are not a good indicator of heavy metal exposure in the studied species. Our data suggest, however, that they may indicate spatial variation in soil pH. We also tested for the possible effects of pollution on oribatid species number and abundances. There were pollution-related differences in relative abundances of mites but not in the number of species. We discuss the relationship between soil pH, calcium requirements and skeletal malformations of oribatid mites.

Granulation tissue was induced in hydroxyapatite-coated cellulose sponges with subcutaneous implantation in rats. A massive inflammatory reaction with an intense foreign body reaction and an increased invasion of fibrovascular tissue was observed by days 1-3 post-operation, whereas tissue growth into the uncoated control implants was much slower and took place mainly on their surfaces. The foreign body reaction in apatite-coated sponges declined after post-operative day 14, and no obvious differences were seen between the two cellulose sponges from 1 month up to 1 year after implantation. The apatite-coated implants attracted macrophages and fibroblasts, and favored angiogenesis. The excessive connective tissue formation was histologically normal, synthesized the major extracellular matrix molecules in a normal ratio and did not seem to disturb the animals in any way. These results warrant further investigations on clinical applicability of hydroxyapatite-coated cellulose sponges, when fast proliferation of connective tissue is desirable.

Regenerated cellulose sponges were coated biomimetically with hydroxyapatite to increase their osteogenic properties. Induction of apatite precipitation was carried out with bioactive glass in simulated body fluid (SBF) for 24 h and the final coating was carried out in 1.5 x concentrated SBF for 14 days. Biomimetically mineralized and non-mineralized sponges were then implanted into standard size femoral cortical defects of rats, and the invasion of bone into the implant was followed up to one year. The apatite coating did not improve the osteoconductive property of cellulose in this rat cortical defect model. In fact, it generated a strong and highly cellular inflammatory reaction and less osteoid tissue. The biomimetic implants contained more immunodetectable TGFbeta1 (a strong stimulator of fibroblast activity) than untreated implants, and also bound more TGFbeta1 in vitro, which could, at least in part, explain the fibrotic invasion of biomimetically mineralized sponges.

Integrins mediate cell adhesion to extracellular matrix components. Integrin alpha 1 beta 1 is a collagen receptor expressed on many mesenchymal cells, but mice deficient in alpha 1 integrin (alpha1-KO) have no gross structural defects. Here, the regeneration of a fractured long bone was studied in alpha1-KO mice. These mice developed significantly less callus tissue than the wild-type (WT) mice, and safranin staining revealed a defect in cartilage formation. The mRNA levels of nine extracellular matrix genes in calluses were evaluated by Northern blotting. During the first 9 days the mRNA levels of cartilage-related genes, including type II collagen, type IX collagen, and type X collagen, were lower in alpha1-KO mice than in WT mice, consistent with the reduced synthesis of cartilaginous matrix appreciated in tissue sections. Histological observations also suggested a diminished number of chondrocytes in the alpha 1-KO callus. Proliferating cell nuclear antigen staining revealed a reduction of mesenchymal progenitors at the callus site. Although, the number of mesenchymal stem cells (MSCs) obtained from WT and alpha 1-KO whole marrow was equal, in cell culture the proliferation rate of the MSCs of alpha 1-KO mice was slower, recapitulating the in vivo observation of reduced callus cell proliferation. The results demonstrate the importance of proper collagen-integrin interaction in fracture healing and suggest that alpha1 integrin plays an essential role in the regulation of MSC proliferation and cartilage production.

Elastin and collagen concentrations were determined in intimal-medial samples of ascending aortas from healthy controls of different ages and from 20 patients with annuloaortic ectasia (AAE). Five patients had the Marfan syndrome. In controls the highest elastin concentrations (estimated from desmosine concentrations or insoluble residues after hot-alkali extraction) were found in children. During aging until 60 years, elastin concentration decreased when determined by the hot-alkali extraction method while desmosine concentration changed less. Aorta samples from the Marfan-syndrome patients showed a great variation of elastin concentration from total lack to normal values. Samples from the other AAE patients could be divided into two groups. One contained clearly less elastin and more collagen than the controls whereas in the other group this difference was less marked. Histological examination of the aortic wall of the first group also showed marked fibrosis accompanied by severe elastin fragmentation and acellularity. From the 15 non-Marfan patients 14 were men. By means of clinical examination these patients could also be divided into "familial" and "nonfamilial" groups, because increased diameter of the aortic root was found in relatives of almost half of the patients. However, there were no differences in elastin and collagen concentrations between the familial and nonfamilial cases. As well, no correlation was found between biochemical findings and diameters of the aortic roots. These results point to altered elastin and/or collagen metabolism in the aortic wall of AAE patients.

The effect of cortisol on the synthesis of glycosaminoglycans (GAGs) was studied in cultured human aortic smooth muscle cells. Cortisol, at a level slightly exceeding the physiological concentration (10(-6) M), decreased the synthesis of hyaluronic acid (HA) by 50% but had no significant effect on the synthesis of sulphated GAGs. The ratio of HA to sulphated GAGs decreased by 47%. These effects were most marked in the fraction secreted into the culture medium. Cortisol neither affected the activity of the hyaluronic acid synthesizing enzyme complex in a cell-free system nor the molecular weight distribution of hyaluronic acid. We suggest that the atherogenity of cortisol and stress may be associated with their effect on the synthesis of HA by the smooth muscle cells of the arterial wall.