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1.
Janina Petkeviciene Jurate Klumbiene Sandrita Simonyte Indre Ceponiene Kristina Jureniene Vilma Kriaucioniene Asta Raskiliene Alina Smalinskiene Vaiva Lesauskaite 《PloS one》2014,9(10)
Background
The roots of adult hypertension go back to childhood. This study aimed to examine the independent effects of physical, behavioural and genetic factors identified in childhood and mid-adulthood for prediction of adult hypertension.Methods
The study subjects were participants of the Kaunas Cardiovascular Risk Cohort study started in 1977 (n = 1082, age 12–13 years). In 2012, a total of 507 individuals (63.9% of eligible sample) participated in the 35-year follow-up survey. Health examination involved measurements of blood pressure (BP), anthropometric parameters, and interview about health behaviours. Subjects were genotyped for AGT (M235T), ACE (I/D, rs4340), ADM (rs7129220), and CACNB2 (rs12258967) genes polymorphisms. A genetic risk score was calculated as the sum of the number of risk alleles at each of four single nucleotide polymorphisms.Results
AGT TT genotype male carriers had the highest mean values of systolic BP in childhood. In females, ADM genotype AA was associated with the highest values of systolic and diastolic BP, while CACNB2 genotype CC carriers had the highest values of diastolic BP in childhood. Systolic and diastolic BP in childhood, gain in BMI from childhood to adulthood, and risky alcohol consumption predicted hypertension in middle-aged men. In women, genetic risk score together with diastolic BP in childhood and gain in BMI were significant predictors of adult hypertension. The comparison of four nested logistic regression models showed that the prediction of hypertension improved significantly after the addition of BMI gain. Genetic risk score had a relatively weak effect on the improvement of the model performance in women.Conclusions
BP in childhood and the gain in BMI from childhood to adulthood were significant predictors of adult hypertension in both genders. Genetic risk score in women and risky alcohol consumption in men were independently related with the risk of adult hypertension. 相似文献2.
Kristina Kirschner Shamith A. Samarajiwa Jonathan M. Cairns Suraj Menon Pedro A. Pérez-Mancera Kosuke Tomimatsu Camino Bermejo-Rodriguez Yoko Ito Tamir Chandra Masako Narita Scott K. Lyons Andy G. Lynch Hiroshi Kimura Tetsuya Ohbayashi Simon Tavaré Masashi Narita 《PLoS genetics》2015,11(3)
The downstream functions of the DNA binding tumor suppressor p53 vary depending on the cellular context, and persistent p53 activation has recently been implicated in tumor suppression and senescence. However, genome-wide information about p53-target gene regulation has been derived mostly from acute genotoxic conditions. Using ChIP-seq and expression data, we have found distinct p53 binding profiles between acutely activated (through DNA damage) and chronically activated (in senescent or pro-apoptotic conditions) p53. Compared to the classical ‘acute’ p53 binding profile, ‘chronic’ p53 peaks were closely associated with CpG-islands. Furthermore, the chronic CpG-island binding of p53 conferred distinct expression patterns between senescent and pro-apoptotic conditions. Using the p53 targets seen in the chronic conditions together with external high-throughput datasets, we have built p53 networks that revealed extensive self-regulatory ‘p53 hubs’ where p53 and many p53 targets can physically interact with each other. Integrating these results with public clinical datasets identified the cancer-associated lipogenic enzyme, SCD, which we found to be directly repressed by p53 through the CpG-island promoter, providing a mechanistic link between p53 and the ‘lipogenic phenotype’, a hallmark of cancer. Our data reveal distinct phenotype associations of chronic p53 targets that underlie specific gene regulatory mechanisms. 相似文献
3.
While uniparental transmission of mtDNA is widespread and dominating in eukaryotes leaving mutation as the major source of genotypic diversity, recently, biparental inheritance of mitochondrial genes has been demonstrated in reciprocal crosses of Pelargonium zonale and P. inquinans. The thereby arising heteroplasmy carries the potential for recombination between mtDNAs of different descent, i.e. between the parental mitochondrial genomes. We have analyzed these Pelargonium hybrids for mitochondrial intergenomic recombination events by examining differences in DNA blot hybridization patterns of the mitochondrial genes atp1 and cob. Further investigation of these genes and their flanking regions using nucleotide sequence polymorphisms and PCR revealed DNA segments in the progeny, which contained both P. zonale and P. inquinans sequences suggesting an intergenomic recombination in hybrids of Pelargonium. This turns Pelargonium into an interesting subject for studies of recombination and evolutionary dynamics of mitochondrial genomes. 相似文献
4.
Janina Kaczanowska Leonora Wychowaniec Marek Ostrowski 《Development genes and evolution》1982,191(5):325-330
Summary An easy and sensitive method is reported here for testing the similarities of individual patterns by photographically transforming maps of these patterns to given, deductively chosen conventions involving constant distances between selected reference points. A cumulative map is produced by loading all landmarks from a set of individual maps on to one sheet of paper. The use of various a priori conventions results in variable cumulative maps, which are then optically transformed on an analog digital converter, with additional input for optical picture processing. The densitometrical maps thus obtained may be compared as to the cumulative degree of areas of maximal and minimal density of landmarks. The best conventions are those that yield the map with the most contrast.Maps of spatial patterns of the sites of contractile vacuole pore (CVP) primordia in an early stage of divisional morphogenesis of the ciliateChilodonella steini were compared after four different transformations and adjustments of the same set of individual maps. The best focusing of the sites of CVP differentiation was achieved by use of the postoral axis, defined by the center of the oral apparatus and the posterior end of the cell as the scaling parameter. The composite domain map obtained by optical transformation of this cumulative map could distinguish the specific CVP territories observed in earlier work (Kaczanowska 1981). These results confirm earlier findings that indicated the site of the oral apparatus is an important reference point in CVP primordia positioning. They also strongly suggest the existence of an overriding scaling factor governing the positioning of sites of differentiation in both dimensions of the developmental field. The method of superposition and scaling of pattern maps is generally applicable to situations in which pattern elements appear at discrete points on a flat surface. 相似文献
5.
Mahasweta Saha Francisco R. Barboza Paul J. Somerfield Balsam Al‐Janabi Miriam Beck Janina Brakel Maysa Ito Christian Pansch Jennifer C. Nascimento‐Schulze Stina Jakobsson Thor Florian Weinberger Yvonne Sawall 《Global Change Biology》2020,26(2):417-430
Marine heatwaves have been observed worldwide and are expected to increase in both frequency and intensity due to climate change. Such events may cause ecosystem reconfigurations arising from species range contraction or redistribution, with ecological, economic and social implications. Macrophytes such as the brown seaweed Fucus vesiculosus and the seagrass Zostera marina are foundation species in many coastal ecosystems of the temperate northern hemisphere. Hence, their response to extreme events can potentially determine the fate of associated ecosystems. Macrophyte functioning is intimately linked to the maintenance of photosynthesis, growth and reproduction, and resistance against pathogens, epibionts and grazers. We investigated morphological, physiological, pathological and chemical defence responses of western Baltic Sea F. vesiculosus and Z. marina populations to simulated near‐natural marine heatwaves. Along with (a) the control, which constituted no heatwave but natural stochastic temperature variability (0HW), two treatments were applied: (b) two late‐spring heatwaves (June, July) followed by a summer heatwave (August; 3HW) and (c) a summer heatwave only (1HW). The 3HW treatment was applied to test whether preconditioning events can modulate the potential sensitivity to the summer heatwave. Despite the variety of responses measured in both species, only Z. marina growth was impaired by the accumulative heat stress imposed by the 3HW treatment. Photosynthetic rate, however, remained high after the last heatwave indicating potential for recovery. Only epibacterial abundance was significantly affected in F. vesiculosus. Hence both macrophytes, and in particular F. vesiculosus, seem to be fairly tolerant to short‐term marine heatwaves at least at the intensities applied in this experiment (up to 5°C above mean temperature over a period of 9 days). This may partly be due to the fact that F. vesiculosus grows in a highly variable environment, and may have a high phenotypic plasticity. 相似文献
6.
Expansion to a total of 11-17 sequential alanine residues from the normal number of 10 in the polyadenine-binding protein nuclear-1 (PABPN1) results in formation of intranuclear, fibrillar inclusions in skeletal muscle and hypothalamic neurons in adult-onset, dominantly inherited oculopharyngeal muscular dystrophy (OPMD). To understand the role that homopolymeric length may play in the protein misfolding that leads to the inclusions, we analyzed the self-assembly of synthetic poly-(L-alanine) peptides having 3-20 residues. We found that the conformational transition and structure of polyalanine (polyAla) assemblies in solution are not only length-dependent but also are determined by concentration, temperature, and incubation time. No beta-sheet complex was detected for those peptides characterized by n < 8, where n is number of alanine residues. A second group of peptides with 7 < n < 15 showed varying levels of complex formation, while for those peptides having n > 15, the interconversion process from the monomeric to the beta-sheet complex was complete under any of the tested experimental conditions. Unlike the typical tinctorial properties of amyloid fibrils, polyalanine fibrils did not show fluorescence with thioflavin T or apple-green birefringence with Congo red; however, like amyloid, X-ray diffraction showed that the peptide chains in these fibrils were oriented normal to the fibril axis (i.e., in the cross-beta arrangement). Neighboring beta-sheets are quarter-staggered in the hydrogen-bonding direction such that the alanine side-chains were closely packed in the intersheet space. Strong van der Waals contacts between side-chains in this arrangement likely account for the high stability of the macromolecular fibrillar complex in solution over a wide range of temperature (5-85 degrees C), and pH (2-10.5), and its resistance to denaturant (< 8 M urea) and to proteases (protease K, trypsin). We postulate that a similar stabilization of an expanded polyalanine stretch could form a core beta-sheet structure that mediates the intermolecular association of mutant proteins into fibrillar inclusions in human pathologies. 相似文献
7.
We propose a machine-learning approach to sequence-based prediction of protein crystallizability in which we exploit subtle differences between proteins whose structures were solved by X-ray analysis [or by both X-ray and nuclear magnetic resonance (NMR) spectroscopy] and those proteins whose structures were solved by NMR spectroscopy alone. Because the NMR technique is usually applied on relatively small proteins, sequence length distributions of the X-ray and NMR datasets were adjusted to avoid predictions biased by protein size. As feature space for classification, we used frequencies of mono-, di-, and tripeptides represented by the original 20-letter amino acid alphabet as well as by several reduced alphabets in which amino acids were grouped by their physicochemical and structural properties. The classification algorithm was constructed as a two-layered structure in which the output of primary support vector machine classifiers operating on peptide frequencies was combined by a second-level Naive Bayes classifier. Due to the application of metamethods for cost sensitivity, our method is able to handle real datasets with unbalanced class representation. An overall prediction accuracy of 67% [65% on the positive (crystallizable) and 69% on the negative (noncrystallizable) class] was achieved in a 10-fold cross-validation experiment, indicating that the proposed algorithm may be a valuable tool for more efficient target selection in structural genomics. A Web server for protein crystallizability prediction called SECRET is available at http://webclu.bio.wzw.tum.de:8080/secret. 相似文献
8.
Scheuch E Spieker J Venner M Siegmund W 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):464-470
The long-acting antibiotic tulathromycin is on the marked for treatment of pulmonary infection of cattle, swine and horses. To measure disposition and distribution of tulathromycin in foals, a high throughput method was developed for horse plasma (calibration range: 0.006-0.8 microg/mL) and broncho-alveolar cells (calibration range: 0.1-4.0 microg/10(9)cells) using tandem mass spectrometry. Tulathromycin was extracted from plasma and broncho-alveolar fluid using cation exchange cartridges with acetonitrile/ammonia (95:5, v/v). The chromatography was performed isocratically with a mobile phase consisting of 5 mM ammonium formiate buffer/acetonitrile (30:70, v/v). The mass spectrometer operated in selected ion mode with atmospheric pressure chemical ionization to monitor the respective MH+ ions m/z 577.3 for tulathromycin and m/z 679.3 for the internal standard roxithromycin. All quality parameters fulfilled the international criteria for bioanalytical method validation and were successfully applied to the determination of tulathromycin in plasma of foals and broncho-alveolar cells. In foals, tulathromycin after intramuscular administration was rapidly absorbed, widely distributed and slowly eliminated. It cumulated manifold in broncho-alveolar cells. 相似文献
9.
Słodkowska J Rojo MG 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(4):570-578
The development of small molecule inhibitors of growth factor receptors, and the discovery of somatic mutations of the tyrosine kinase domain, have resulted in new paradigms for cancer therapy. Digital microscopy is an important tool for surgical pathologists. The achievements in the digital pathology field have modified the workflow of pathomorphology labs, enhanced the pathologist's role in diagnostics, and increased their contribution to personalized targeted medicine. Digital image analysis is now available in a variety of platforms to improve quantification performance of diagnostic pathology. We here describe the state of digital microscopy as it applies to the field of quantitative immunohistochemistry of biomarkers related to the clinical personalized targeted therapy of breast cancer, non-small lung cancer and colorectal cancer: HER-2, EGFR, KRAS and BRAF genes. The information is derived from the experience of the authors and a review of the literature. 相似文献
10.
Noriyuki Satoh Kunifumi Tagawa Christopher J. Lowe Jr‐Kai Yu Takeshi Kawashima Hiroki Takahashi Michio Ogasawara Marc Kirschner Kanako Hisata Yi‐Hsien Su John Gerhart 《Genesis (New York, N.Y. : 2000)》2014,52(12):925-934
As a group closely related to chordates, hemichordate acorn worms are in a key phylogenic position for addressing hypotheses of chordate origins. The stomochord of acorn worms is an anterior outgrowth of the pharynx endoderm into the proboscis. In 1886 Bateson proposed homology of this organ to the chordate notochord, crowning this animal group “hemichordates.” Although this proposal has been debated for over a century, the question still remains unresolved. Here we review recent progress related to this question. First, the developmental mode of the stomochord completely differs from that of the notochord. Second, comparison of expression profiles of genes including Brachyury, a key regulator of notochord formation in chordates, does not support the stomochord/notochord homology. Third, FoxE that is expressed in the stomochord‐forming region in acorn worm juveniles is expressed in the club‐shaped gland and in the endostyle of amphioxus, in the endostyle of ascidians, and in the thyroid gland of vertebrates. Based on these findings, together with the anterior endodermal location of the stomochord, we propose that the stomochord has evolutionary relatedness to chordate organs deriving from the anterior pharynx rather than to the notochord. genesis 52:925–934, 2014. © 2014 Wiley Periodicals, Inc. 相似文献