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91.
Jarna C Hannukainen Pirjo Nuutila Jaakko Kaprio Olli J Heinonen Urho M Kujala Tuula Janatuinen Tapani R?nnemaa Jukka Kapanen Merja Haaparanta-Solin Tapio Viljanen Juhani Knuuti Kari K Kalliokoski 《Journal of applied physiology》2006,101(5):1303-1311
We investigated heredity-independent effects of increased physical activity and aerobic fitness on skeletal muscle free fatty acid (FFA) uptake, perfusion, and their heterogeneity at rest and during exercise. Also, the relationship between local skeletal muscle FFA uptake and perfusion was studied. Nine young adult male monozygotic twin pairs with significant difference in physical activity [229 min (SD 156) average time spent for conditioning exercise per week in more and 98 min (SD 71) in less active twins, P = 0.013] and aerobic fitness [18% (SD 10) difference in maximum O2 uptake] between brothers were studied using positron emission tomography. Submaximal knee-extension exercise increased perfusion, FFA uptake, and oxygen uptake in quadriceps femoris muscles 6-10 times compared with resting values (P < 0.001). More active twins tended to utilize more oxygen, while no differences were found in muscle perfusion or FFA uptake between groups. Mean perfusion and FFA uptake correlated strongly at a whole muscle level, both at rest (r = 0.97, P = 0.03 in more and r = 0.98, P = 0.02 in less active twins) and during exercise (r = 0.99, P = 0.01 and r = 0.94, P = 0.06), but at the voxel level (87 mm3) correlation was only moderate during exercise [r = 0.73 (SD 0.08) vs. r = 0.74 (SD 0.10), P = 0.92] and weak at rest [r = 0.28 (SD 0.13) vs. r = 0.33 (SD 0.21), P = 0.58]. Exercise decreased both perfusion and FFA uptake heterogeneity within the muscles (P < 0.001) similarly in both groups. In conclusion, long-term history of moderately increased physical activity tends to enhance muscle oxidative metabolism, but it does not have any significant influence on the FFA uptake or perfusion rates or their heterogeneity in skeletal muscle. Submaximal knee-extension exercise decreases heterogeneity of muscle FFA uptake and perfusion and improves matching between local muscle perfusion and FFA uptake. Thus it seems that the genetic influence is more important to determine the heterogeneity of perfusion and FFA uptake in skeletal muscle than exercise training. 相似文献
92.
P. Majander-Nordenswan Markku Sainio Ossi Turunen Juha Jääskeläinen Olli Carpén Juha Kere Antti Vaheri 《Human genetics》1998,103(6):662-665
The ERM proteins, ezrin, radixin, and moesin, act as linkers between the plasma membrane and actin cytoskeleton. They are
involved in a variety of cellular functions, such as cell adhesion, migration, and the organization of cell surface structures,
and are highly homologous, both in protein sequence and in functional activity, with merlin/schwannomin, a neurofibromatosis-2-associated
tumor-suppressor protein. We report here the genomic structure and intron junction sequences of the human ezrin gene. Ezrin
consists of 13 exons and spans approximately 24 kb genomic DNA. The coding parts of the exons range in size from 12 bp to
275 bp and the introns from 182 bp to 7 kb. The genomic structures of ezrin and moesin are highly conserved, suggesting their
recent divergence. Radiation hybrid mapping has refined the location of ezrin to the interval between D6S442 and D6S281.
Received: 1 June 1998 / Accepted: 25 August 1998 相似文献
93.
Andrea Ganna F. Kyle Satterstrom Seyedeh M. Zekavat Indraniel Das Mitja I. Kurki Claire Churchhouse Jessica Alfoldi Alicia R. Martin Aki S. Havulinna Andrea Byrnes Wesley K. Thompson Philip R. Nielsen Konrad J. Karczewski Elmo Saarentaus Manuel A. Rivas Namrata Gupta Olli Pietiläinen Connor A. Emdin Benjamin M. Neale 《American journal of human genetics》2018,102(6):1204-1211
94.
Plasma membrane calcium ATPase 4 (PMCA4) co‐ordinates calcium and nitric oxide signaling in regulating murine sperm functional activity 下载免费PDF全文
Kristine E. Olli Kun Li Deni S. Galileo Patricia A. Martin‐DeLeon 《Journal of cellular physiology》2018,233(1):11-22
Reduced sperm motility (asthenospermia) and resulting infertility arise from deletion of the Plasma Membrane Ca2+‐ATPase 4 (Pmca4) gene which encodes the highly conserved Ca2+ efflux pump, PMCA4. This is the major Ca2+ clearance protein in murine sperm. Since the mechanism underlying asthenospermia in PMCA4's absence or reduced activity is unknown, we investigated if sperm PMCA4 negatively regulates nitric oxide synthases (NOSs) and when absent NO, peroxynitrite, and oxidative stress levels are increased. Using co‐immunoprecipitation (Co‐IP) and Fluorescence Resonance Energy Transfer (FRET), we show an association of PMCA4 with the NOSs in elevated cytosolic [Ca2+] in capacitated and Ca2+ ionophore‐treated sperm and with neuronal (nNOS) at basal [Ca2+] (ucapacitated sperm). FRET efficiencies for PMCA4‐eNOS were 35% and 23% in capacitated and uncapacitated sperm, significantly (p < 0.01) different, with the molecules being <10 nm apart. For PMCA4‐nNOS, this interaction was seen only for capacitated sperm where FRET efficiency was 24%, significantly (p < 0.05) higher than in uncapacitated sperm (6%). PMCA4 and the NOSs were identified as interacting partners in a quaternary complex that includes Caveolin1, which co‐immunoprecipitated with eNOS in a Ca2+‐dependent manner. In Pmca4?/? sperm NOS activity was elevated twofold in capacitated/uncapacitated sperm (vs. wild‐type), accompanied by a twofold increase in peroxynitrite levels and significantly (p < 0.001) increased numbers of apoptotic germ cells. The data support a quaternary complex model in which PMCA4 co‐ordinates Ca2+ and NO signaling to maintain motility, with increased NO levels resulting in asthenospermia in Pmca4?/? males. They suggest the involvement of PMCA4 mutations in human asthenospermia, with diagnostic relevance. 相似文献
95.
Isolation and Characterization of a Hantavirus from Lemmus sibiricus: Evidence for Host Switch during Hantavirus Evolution 总被引:9,自引:0,他引:9 下载免费PDF全文
Olli Vapalahti ke Lundkvist Vadim Fedorov Christopher J. Conroy Sirpa Hirvonen Angelina Plyusnina Kirill Nemirov Karl Fredga Joseph A. Cook Jukka Niemimaa Asko Kaikusalo Heikki Henttonen Antti Vaheri Alexander Plyusnin 《Journal of virology》1999,73(7):5586-5592
A novel hantavirus, first detected in Siberian lemmings (Lemmus sibiricus) collected near the Topografov River in the Taymyr Peninsula, Siberia (A. Plyusnin et al., Lancet 347:1835-1836, 1996), was isolated in Vero E6 cells and in laboratory-bred Norwegian lemmings (Lemmus lemmus). The virus, named Topografov virus (TOP), was most closely related to Khabarovsk virus (KBR) and Puumala viruses (PUU). In a cross focus reduction neutralization test, anti-TOP Lemmus antisera showed titers at least fourfold higher with TOP than with other hantaviruses; however, a rabbit anti-KBR antiserum neutralized TOP and KBR at the same titer. The TOP M segment showed 77% nucleotide and 88% amino acid identity with KBR and 76% nucleotide and 82% amino acid identity with PUU. However, the homology between TOP and the KBR S segment was disproportionately higher: 88% at the nucleotide level and 96% at the amino acid level. The 3' noncoding regions of KBR and the TOP S and M segments were alignable except for 113- and 58-nucleotide deletions in KBR. The phylogenetic relationships of TOP, KBR, and PUU and their respective rodent carriers suggest that an exceptional host switch took place during the evolution of these viruses; while TOP and KBR are monophyletic, the respective rodent host species are only distantly related. 相似文献
96.
Pellinen T Tuomi S Arjonen A Wolf M Edgren H Meyer H Grosse R Kitzing T Rantala JK Kallioniemi O Fässler R Kallio M Ivaska J 《Developmental cell》2008,15(3):371-385
Adherent cells undergo remarkable changes in shape during cell division. However, the functional interplay between cell adhesion turnover and the mitotic machinery is poorly understood. The endo/exocytic trafficking of integrins is regulated by the small GTPase Rab21, which associates with several integrin alpha subunits. Here, we show that targeted trafficking of integrins to and from the cleavage furrow is required for successful cytokinesis, and that this is regulated by Rab21. Rab21 activity, integrin-Rab21 association, and integrin endocytosis are all necessary for normal cytokinesis, which becomes impaired when integrin-mediated adhesion at the cleavage furrow fails. We also describe a chromosomal deletion and loss of Rab21 gene expression in human cancer, which leads to the accumulation of multinucleate cells. Importantly, reintroduction of Rab21 rescued this phenotype. In conclusion, Rab21-regulated integrin trafficking is essential for normal cell division, and its defects may contribute to multinucleation and genomic instability, which are hallmarks of cancer. 相似文献
97.
Jouni Smed Kari Salonen Mika Johnsson Tommi Johtela Olli S. Nevalainen 《Flexible Services and Manufacturing Journal》2003,15(1):19-35
In printed circuit board (PCB) assembly, the majority of electronic components are inserted by high-speed placement machines. Although the efficient utilization of the machinery is important for a manufacturer, it is hard to fully realize in high-mix low-volume production environments. On the machine level, the component setup strategy adopted by the manufacturer has a significant impact on the overall production efficiency. Usually, the setup strategy is formulated as a part type grouping problem or a minimum setup problem. In this article, we consider a hybridization of these two problems for the single machine case: The object function to be minimized includes a weighted sum of the number of part type groups (giving the number of setup occasions) and the number of feeder changeovers. We present algorithms for the problem and compare their efficiency. 相似文献
98.
Variability of the distribution of differentiation pathway choices regulated by a multipotent delayed stochastic switch 总被引:1,自引:1,他引:0
We study the plasticity of a delayed stochastic model of a genetic toggle switch as a multipotent differentiation pathway switch, at the single cell and cell population levels, by observing distributions of differentiation pathways choices of genetically homogeneous cell populations. Assuming a model of stochastic pathway determination of cell differentiation that is regulated by the proteins of the switch, we vary the proteins’ expression level and degradation rates, which cells are known to be able to regulate, to vary mean level, noise, and bias of the proteins’ expression levels. It is shown that small changes in each of these dynamical features significantly and distinctively affects the dynamics of the switch at the single cell level and thus, the cell differentiation patterns. The regulation of these features allows cells to regulate their pluripotency and cell populations’ distribution of lineage choice, suggesting that the stochastic switch has high plasticity regarding differentiation pathway choice regulation, thus providing adaptability to environmental stresses and changes. 相似文献
99.
Jorma A Määttä Kaisa Olli Tiina Henttinen Minna T Tuittila Klaus Elenius Markku Salmivirta 《BMC cell biology》2009,10(1):5-7
Background
Nuclear localization of proteolytically formed intracellular fragment of ErbB4 receptor tyrosine kinase has been shown to promote cell survival, and nuclear localization of ErbB4 receptor has been described in human breast cancer. Tumor necrosis factor alpha converting enzyme (TACE) initiates the proteolytic cascade leading to ErbB4 intracellular domain formation. Interactions between matrix metalloproteases and heparan sulfate have been described, but the effect of cell surface heparan sulfate on TACE activity has not been previously described. 相似文献100.
Oresmaa L Kotikoski H Haukka M Oksala O Pohjala E Vapaatalo H Vainiotalo P Aulaskari P 《Bioorganic & medicinal chemistry letters》2006,16(8):2144-2147
Esters of 1-(H)-imidazole-5-nitrolic acid and 1-methyl-imidazole-5-carboxamide oxime were prepared to study the effect of esterification on the ocular effects of these compounds. Esterifications were performed with acid chloride. Acid chloride also reacts with the ring nitrogen of 1-(H)-imidazole-5-nitrolic acid, but the desired esters could be selectively prepared by adjustment of the reaction conditions. Esterification led to loss of the ocular effects exhibited by the parent compounds. 相似文献