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991.
LE Reinius N Acevedo M Joerink G Pershagen SE Dahlén D Greco C Söderhäll A Scheynius J Kere 《PloS one》2012,7(7):e41361
Methylation of cytosines at CpG sites is a common epigenetic DNA modification that can be measured by a large number of methods, now even in a genome-wide manner for hundreds of thousands of sites. The application of DNA methylation analysis is becoming widely popular in complex disorders, for example, to understand part of the "missing heritability". The DNA samples most readily available for methylation studies are derived from whole blood. However, blood consists of many functionally and developmentally distinct cell populations in varying proportions. We studied whether such variation might affect the interpretation of methylation studies based on whole blood DNA. We found in healthy male blood donors there is important variation in the methylation profiles of whole blood, mononuclear cells, granulocytes, and cells from seven selected purified lineages. CpG methylation between mononuclear cells and granulocytes differed for 22% of the 8252 probes covering the selected 343 genes implicated in immune-related disorders by genome-wide association studies, and at least one probe was differentially methylated for 85% of the genes, indicating that whole blood methylation results might be unintelligible. For individual genes, even if the overall methylation patterns might appear similar, a few CpG sites in the regulatory regions may have opposite methylation patterns (i.e., hypo/hyper) in the main blood cell types. We conclude that interpretation of whole blood methylation profiles should be performed with great caution and for any differences implicated in a disorder, the differences resulting from varying proportions of white blood cell types should be considered. 相似文献
992.
A gene expression atlas of the domestic pig 总被引:1,自引:0,他引:1
993.
The affinities of Piopio Turnagra capensis, an extinct New Zealand passerine, remain poorly known. It has been included into or associated with several bird families (Calleatidae, Cracticidae, Pachycephalidae, Ptilonorhynchidae, Turdidae), often on tenuous grounds. We reassessed Turnagra phylogenetic relationships using nuclear and mitochondrial sequences and a set of morphological and behavioural traits. Molecular and phenotypic characters strongly suggest a novel hypothesis, congruently placing Turnagra in Oriolidae, a highly dispersive corvoid family distributed from the Austro-Papuan landmass to Eurasia and Africa, but missing from the Pacific islands. We show also that the published molecular support to link Turnagra with Ptilonorhynchidae was biased by the use of incorrect genetic data and weak analyses. 相似文献
994.
Sporiš G Harasin D Bok D Matika D Vuleta D 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(10):2872-2882
ABSTRACT: Spori?, G, Milanovi?, Z, Harasin, D, Trajkovi?, N, and Vuleta, D. Effects of a training program for special operations battalion on soldiers fitness characteristics. J Strength Cond Res 26(10): 2872-2882, 2012-The aim of this study was to investigate the effects of special operations battalion (SOB) training program on soldiers' fitness parameters. The research was conducted on a sample of 25 members (mean ± SD: age 27.93 ± 5.12 years, height 178.64 ± 6.91 cm, body mass 81.42 ± 9.18 kg) of the Croatian Armed Forces for SOB, divided into control and experimental groups. Total duration of the SOB basic training was 62 days. The sample of variables consists of 12 tests for the assessment of fitness characteristics, 2 tests for functional capacity, and 18 morphological measures. Morphological parameters were measured according to the instructions of the International Biological Program. Fitness characteristics were measured with the following tests: 1-kg medicine ball throw from a seated position, standing broad jump (SBJ), relative sergeant test, 20-m sprint, the maximum thrust from the bench, push-ups in 2 minutes (PU2minutes), sit-ups in 2 minutes (SU2minutes), pull-ups (PU), thrust from the bench with 70% of body weight (BP70%), crawling and jumping, agility test 93639 with turn (A9-3-6-3-9), and sit and reach. Functional abilities were evaluated with 2 tests: 3,200 m running (SK3200) and 300 yards running (MBI3Y). There was a statistically significant difference in a set of fitness characteristics variables analyzed between the 2 groups in initial and final measurements in the multivariate level. Analyzing the results of t-test, differences of variables, it was evident that the difference after the SOB program occurred in 7 variables in the experimental group: SBJ, PU2minutes, SU2minutes, PU, BP70%, MBI3Y, and SK3200. Basic training for SOB during 8 weeks has produced significant burnout of the body for the participants who have completed their training. This led to a reduction in fitness performance manifested through the tested variables. 相似文献
995.
Lon D. Ridgway Michael D. Wetzel Dario Marchetti 《Journal of cellular biochemistry》2010,111(5):1299-1309
Mechanisms of brain metastatic melanoma (BMM) remain largely unknown. Understanding the modulation of signaling pathways that alter BMM cell invasion and metastasis is critical to develop new therapies for BMM. Heparanase has been widely implicated in cancer and is the dominant mammalian endoglycosidase which degrades heparan sulfate chains of proteoglycans (HSPG) including syndecans (SDCs). Recent findings also indicate that heparanase possesses non‐enzymatic functions in its latent form. We hypothesized that extracellular heparanase modulates BMM cell signaling by involving SDC1/4 carboxy terminal—associated proteins and downstream targets. We digested BMM cell surface HS with human recombinant active or latent heparanase to delineate their effects on cytoskeletal dynamics and cell invasiveness. We identified the small GTPase guanine nucleotide exchange factor‐H1 (GEF‐H1) as a new component of a SDC signaling complex that is differentially expressed in BMM cells compared to corresponding non‐metastatic counterparts. Second, knockdown of GEF‐H1, SDC1, or SDC4 decreased BMM cell invasiveness and GEF‐H1 modulated small GTPase activity of Rac1 and RhoA in conjunction with heparanase treatment. Third, both active and latent forms of heparanase affected Rac1 and RhoA activity; notably increasing RhoA activity. Both forms of heparanase were found to mediate the expression and subcellular localization of GEF‐H1, and treatment of BMM with latent heparanase modulated SDC1/4 gene expression. Finally, treatment with exogenous heparanase downregulated BMM cell invasion. These studies indicate the relevance of heparanase signaling pathways in BMM progression, and provide insights into the molecular mechanisms regulating HSPG signaling in response to exogenous heparanase. J. Cell. Biochem. 111: 1299–1309, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
996.
Gabriele Schino Stefano Scucchi Dario Maestripieri Pier Giovanni Turillazzi 《American journal of primatology》1988,16(1):43-50
The hypothesis that allogrooming functions as a tension-reduction mechanism was tested. Tension was measured by the frequency of displacement activities by an animal. Two adult male and 11 adult female Java (or long-tailed) monkeys (Macaca fascicularis) that were relatively unfamiliar with each other were paired 1 hour per day for five consecutive days during the periovulatory portion of the menstrual cycle. Female allogrooming was found to reduce the frequency of male displacement activities both during the course of interaction and outside it, and this decrease was proportional to the amount of allogrooming received. Female allogrooming did not, however, exert long-lasting effects on the frequency of female displacement activities. An increase in the frequency of male displacement activities was recorded during the 10-second interval immediately after the end of the female allogrooming bouts. Neither postinhibitory rebound nor frustration owing to the cessation of a pleasant situation, i.e., the two advanced explanatory hypotheses, accounted for this increase. The results of the present study concur with physiological findings that support the tension-reduction hypothesis. The social function of allogrooming appears quite important and is entirely compatible with the functional hypothesis that emphasizes hygiene. 相似文献
997.
Maternal responsiveness in primates has long been considered emancipated from endocrine factors and entirely dependent on experience and cognition. Here we report that group-living pigtail macaque females increased their rate of interaction with infants in the last weeks of pregnancy in correspondence with an increase in plasma levels of estradiol and progesterone. Estrogen treatment increased the rate at which ovariectomized rhesus females interacted with infants. This is the first evidence that steroid hormones influence maternal responsiveness in anthropoid primates. All untreated ovariectomized females and nonpregnant females interacted with infants, indicating that although estrogen can enhance responsiveness to infants, ovarian or pregnancy hormones are not necessary for the expression of infant-directed behavior in female macaques. The findings of this study suggest fundamental similarities, rather than differences, in the endocrine modulation of maternal responsiveness in primates and other mammals. 相似文献
998.
Dario A. Bianchi Roberto Moran-Ramallal Naseem Iqbal Florian Rudroff Marko D. Mihovilovic 《Bioorganic & medicinal chemistry letters》2013,23(9):2718-2720
A novel and stereoselective synthetic route towards carba-C-nucleosides was investigated applying an enantiodivergent biooxidation strategy by two different Baeyer–Villiger monooxygenases. Within only three chemo-enzymatic steps it was possible to introduce four chiral centers starting from commercially available non-chiral starting material. 相似文献
999.
1000.
Pearce LR Sommer EM Sakamoto K Wullschleger S Alessi DR 《The Biochemical journal》2011,436(1):169-179
The mTOR (mammalian target of rapamycin) protein kinase is an important regulator of cell growth and is a key target for therapeutic intervention in cancer. Two complexes of mTOR have been identified: complex 1 (mTORC1), consisting of mTOR, Raptor (regulatory associated protein of mTOR) and mLST8 (mammalian lethal with SEC13 protein 8) and complex 2 (mTORC2) consisting of mTOR, Rictor (rapamycin-insensitive companion of mTOR), Sin1 (stress-activated protein kinase-interacting protein 1), mLST8 and Protor-1 or Protor-2. Both complexes phosphorylate the hydrophobic motifs of AGC kinase family members: mTORC1 phosphorylates S6K (S6 kinase), whereas mTORC2 regulates phosphorylation of Akt, PKCα (protein kinase Cα) and SGK1 (serum- and glucocorticoid-induced protein kinase 1). To investigate the roles of the Protor isoforms, we generated single as well as double Protor-1- and Protor-2-knockout mice and studied how activation of known mTORC2 substrates was affected. We observed that loss of Protor-1 and/or Protor-2 did not affect the expression of the other mTORC2 components, nor their ability to assemble into an active complex. Moreover, Protor knockout mice display no defects in the phosphorylation of Akt and PKCα at their hydrophobic or turn motifs. Strikingly, we observed that Protor-1 knockout mice displayed markedly reduced hydrophobic motif phosphorylation of SGK1 and its physiological substrate NDRG1 (N-Myc downregulated gene 1) in the kidney. Taken together, these results suggest that Protor-1 may play a role in enabling mTORC2 to efficiently activate SGK1, at least in the kidney. 相似文献