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991.
992.
Joppe W. R. Hovius Maarten F. Bijlsma Gerritje J. W. van der Windt W. Joost Wiersinga Bastiaan J. D. Boukens Jeroen Coumou Anneke Oei Regina de Beer Alex F. de Vos Cornelis van 't Veer Alje P. van Dam Penghua Wang Erol Fikrig Marcel M. Levi Joris J. T. H. Roelofs Tom van der Poll 《PLoS pathogens》2009,5(5)
The causative agent of Lyme borreliosis, the spirochete Borrelia
burgdorferi, has been shown to induce expression of the urokinase
receptor (uPAR); however, the role of uPAR in the immune response against
Borrelia has never been investigated. uPAR not only acts as
a proteinase receptor, but can also, dependently or independently of ligation to
uPA, directly affect leukocyte function. We here demonstrate that uPAR is
upregulated on murine and human leukocytes upon exposure to B.
burgdorferi both in vitro as well as in vivo. Notably, B.
burgdorferi-inoculated C57BL/6 uPAR knock-out mice harbored
significantly higher Borrelia numbers compared to WT controls.
This was associated with impaired phagocytotic capacity of B.
burgdorferi by uPAR knock-out leukocytes in vitro. B.
burgdorferi numbers in vivo, and phagocytotic capacity in vitro,
were unaltered in uPA, tPA (low fibrinolytic activity) and PAI-1 (high
fibrinolytic activity) knock-out mice compared to WT controls. Strikingly, in
uPAR knock-out mice partially backcrossed to a B. burgdorferi
susceptible C3H/HeN background, higher B. burgdorferi numbers
were associated with more severe carditis and increased local TLR2 and
IL-1β mRNA expression. In conclusion, in B. burgdorferi
infection, uPAR is required for phagocytosis and adequate eradication of the
spirochete from the heart by a mechanism that is independent of binding of uPAR
to uPA or its role in the fibrinolytic system. 相似文献
993.
Jos L. Gonzlez‐Snchez Carina A. Zabena María T. Martínez‐Larrad Cristina Fernndez‐Prez Milagros Prez‐Barba Markku Laakso Manuel Serrano‐Ríos 《Obesity (Silver Spring, Md.)》2005,13(5):807-812
Adiponectin is a plasma protein produced by the adipose tissue. Hypoadiponectinemia has been associated with insulin resistance and several components of the metabolic syndrome (MS): type 2 diabetes, obesity, and dyslipidemia. We investigated whether single nucleotide polymorphisms (SNPs) at positions 45 and 276 in the adiponectin gene were associated with features of the MS in 747 unrelated Spanish subjects. The G allele of SNP45 and the G/G genotype of SNP276 were associated with impaired glucose tolerance (p = 0.020 and 0.042, respectively). The G/G genotype for SNP276 was associated with lower serum adiponectin levels as compared with the G/T and T/T genotypes (G/G, 10.10 ± 0.24 μg/mL; G/T, 10.98 ± 0.32 μg/mL; T/T, 12.00 ± 0.92 μg/mL; p = 0.015) even after adjustment for sex, age, BMI, waist‐to‐hip ratio, homeostasis model assessment index, and the degree of glucose tolerance (p = 0.040). We found a significant negative association of circulating adiponectin levels with waist‐to‐hip ratio (r = ?0.42, p < 0.001), sagittal abdominal diameter (r = ?0.24, p < 0.001), triglycerides (r = ?0.32, p < 0.001), homeostasis model assessment index (r = ?0.14, p = 0.001), and uric acid (r = ?0.36, p < 0.001) and positive association with high‐density lipoprotein‐cholesterol (r = 0.41, p < 0.001). Our findings indicate that serum adiponectin levels are associated with several components of the MS. The SNP276 of the adiponectin gene may affect impaired glucose tolerance and hypoadiponectinemia. 相似文献
994.
Adaptive resistance of melanoma cells to RAF inhibition via reversible induction of a slowly dividing de‐differentiated state 下载免费PDF全文
995.
The effect of temperature on male mating signals and female choice in the red mason bee,Osmia bicornis (L.) 下载免费PDF全文
Climate change and the resulting changes in air temperature are known to have a major influence on most animals, especially poikilothermic insects, because they depend on the high enough temperatures to function. Previous studies have shown that various signals can be affected by changes in temperature. However, research into the effect of temperature on mating signals and subsequently communication between mates and on female choice is still rare. In the red mason bee, Osmia bicornis, which emerges early in spring and is therefore subject to extensive temperature changes, females choose suitable males based on, among other criteria, their thorax vibrations and odor. So far there has been no research into the effect of temperature changes on these signals. We therefore investigated whether the environmental temperature has an influence on the male's mating signals by measuring vibrations using a laser vibrometer and collecting male and female odor at different temperatures. Furthermore, we performed behavioral experiments in order to show whether there is an effect of temperature‐induced changes and female choice. Our results showed that rejected males differed in their vibrations between the two temperature settings but accepted ones did not. Temperature changes therefore seem to have a stronger effect on those males that are rejected by the females, whereas the accepted males are the ones that can produce desirable signals despite temperature fluctuations. Furthermore, we found that the differences in odor profiles were greater between temperature settings than between the sexes and that females change their preference for odor with temperature. We conclude that temperature strongly influences the male mating signals and therefore may have a major impact on sexual selection in this species. This is an important aspect to consider, not only in future studies on mating behavior, but also in view of our ever raising temperatures. 相似文献
996.
Fatal hepatocellular carcinoma presenting with oral metastasis in a patient with synchronic primary malignancies of prostate and liver 下载免费PDF全文
997.
Anna Rising Ella Cederlund Carina Palmberg Henrik Uhlhorn Stefan Gaunitz Kerstin Nordling Erik Ågren Elisabet Ihse Gunilla T. Westermark Lars Tjernberg Hans Jörnvall Jan Johansson Per Westermark 《Protein science : a publication of the Protein Society》2017,26(11):2312-2318
Amyloid A (AA) amyloidosis occurs spontaneously in many mammals and birds, but the prevalence varies considerably among different species, and even among subgroups of the same species. The Blue fox and the Gray fox seem to be resistant to the development of AA amyloidosis, while Island foxes have a high prevalence of the disease. Herein, we report on the identification of AA amyloidosis in the Red fox (Vulpes vulpes). Edman degradation and tandem MS analysis of proteolyzed amyloid protein revealed that the amyloid partly was composed of full‐length SAA. Its amino acid sequence was determined and found to consist of 111 amino acid residues. Based on inter‐species sequence comparisons we found four residue exchanges (Ser31, Lys63, Leu71, Lys72) between the Red and Blue fox SAAs. Lys63 seems unique to the Red fox SAA. We found no obvious explanation to how these exchanges might correlate with the reported differences in SAA amyloidogenicity. Furthermore, in contrast to fibrils from many other mammalian species, the isolated amyloid fibrils from Red fox did not seed AA amyloidosis in a mouse model. 相似文献
998.
999.
Two new species in the Chaetoceros socialis complex (Bacillariophyta): C. sporotruncatus and C. dichatoensis,and characterization of its relatives,C. radicans and C. cinctus 下载免费PDF全文
Chetan C. Gaonkar Wiebe H. C. F. Kooistra Carina B. Lange Marina Montresor Diana Sarno 《Journal of phycology》2017,53(4):889-907
The diatom genus Chaetoceros is one of the most abundant and diverse phytoplankton in marine and brackish waters worldwide. Within this genus, Chaetoceros socialis has been cited as one of the most common species. However, recent studies from different geographic areas have shown the presence of pseudo‐cryptic diversity within the C. socialis complex. Members of this complex are characterized by curved chains (primary colonies) aggregating into globular clusters, where one of the four setae of each cell curves toward the center of the cluster and the other three orient outwards. New light and electron microscopy observations as well as molecular data on marine planktonic diatoms from the coastal waters off Chile revealed the presence of two new species, Chaetoceros sporotruncatus sp. nov. and C. dichatoensis. sp. nov. belonging to the C. socialis complex. The two new species are similar to other members of the complex (i.e., C. socialis and C. gelidus) in the primary and secondary structure of the colony, the orientation pattern of the setae, and the valve ultrastructure. The only morphological characters that can be used to differentiate the species of this complex are aspects related to resting spore morphology. The two newly described species are closely related to each other and form a sister clade to C. gelidus in molecular phylogenies. We also provide a phylogenetic status along with the morphological characterization of C. radicans and C. cintus, which are genetically related to the C. socialis complex. 相似文献
1000.