71 results on '"Martina, Weber"'
Search Results
2. DNA-Methylation and Body Composition in Preschool Children: Epigenome-Wide-Analysis in the European Childhood Obesity Project (CHOP)-Study
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Martina Weber, Joaquin Escribano, Dariusz Gruszfeld, Eva Reischl, Ricardo Closa-Monasterolo, Simone Wahl, Piotr Socha, Peter Rzehak, Elvira Verduci, Natàlia Ferré, Jean-Paul Langhendries, Enrica Riva, Richard Saffery, Marcela Covic, Annick Xhonneux, Berthold Koletzko, and Veit Grote
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Epigenomics ,Male ,0301 basic medicine ,Pediatric Obesity ,lcsh:Medicine ,Biology ,White People ,Article ,Childhood obesity ,Body Mass Index ,Epigenesis, Genetic ,03 medical and health sciences ,0302 clinical medicine ,Genetic variation ,medicine ,Humans ,Obesity ,Epigenetics ,Child ,lcsh:Science ,Adiposity ,2. Zero hunger ,Genetics ,Multidisciplinary ,lcsh:R ,dNaM ,DNA ,Epigenome ,DNA Methylation ,Lipid Metabolism ,medicine.disease ,3. Good health ,Glucose ,030104 developmental biology ,Child, Preschool ,030220 oncology & carcinogenesis ,DNA methylation ,Body Composition ,CpG Islands ,Female ,lcsh:Q ,Transcriptome ,Body mass index ,Genome-Wide Association Study - Abstract
Adiposity and obesity result from the interaction of genetic variation and environmental factors from very early in life, possibly mediated by epigenetic processes. Few Epigenome-Wide-Association-Studies have identified DNA-methylation (DNAm) signatures associated with BMI and body composition in children. Body composition by Bio-Impedance-Analysis and genome-wide DNAm in whole blood were assessed in 374 pre-school children from four European countries. Associations were tested by linear regression adjusted for sex, age, centre, education, 6 WBC-proportions according to Houseman and 30 principal components derived from control probes. Specific DNAm variants were identified to be associated with BMI (212), fat-mass (230), fat-free-mass (120), fat-mass-index (24) and fat-free-mass-index (15). Probes in genes SNED1(IRE-BP1), KLHL6, WDR51A(POC1A), CYTH4-ELFN2, CFLAR, PRDM14, SOS1, ZNF643(ZFP69B), ST6GAL1, C3orf70, CILP2, MLLT4 and ncRNA LOC101929268 remained significantly associated after Bonferroni-correction of P-values. We provide novel evidence linking DNAm with (i) altered lipid and glucose metabolism, (ii) diabetes and (iii) body size and composition in children. Both common and specific epigenetic signatures among measures were also revealed. The causal direction with phenotypic measures and stability of DNAm variants throughout the life course remains unclear and longitudinal analysis in other populations is required. These findings give support for potential epigenetic programming of body composition and obesity.
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- 2017
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3. Is there an advantage to staying indoors for pollen allergy sufferers? Composition and quantitative aspects of the indoor pollen spectrum
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Uwe Berger, Maximilian Kmenta, Katharina Bastl, and Martina Weber
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Environmental Engineering ,010504 meteorology & atmospheric sciences ,Pollination ,Indoor air ,Geography, Planning and Development ,Forensic palynology ,Building and Construction ,010501 environmental sciences ,Biology ,Pollen Allergy ,medicine.disease_cause ,01 natural sciences ,Toxicology ,Ground level ,Pollen ,Botany ,medicine ,Ambrosia ,0105 earth and related environmental sciences ,Civil and Structural Engineering - Abstract
The pollen content of the air in an office was assessed together with the dust on the floor and on the desktops as well as the pollen content outside of the building on rooftops and at ground level. The whole pollen spectrum was evaluated (35 different pollen types) with focus on the major aeroallergens. The air samples were measured with Hirst-type pollen traps and the dust samples were evaluated following guidelines in forensic palynology. The same time period was examined on four different sampling days: (1) during the winter as a reference day, (2) during the main pollination period of Betula , (3) during the main pollination period of Poaceae and (4) during the main pollination period of Ambrosia . Pollen concentrations were generally lower in indoor air than in outdoor air (except for the winter day), but showed associations with dust by containing non-seasonal pollen types as well as seasonal pollen. Staying indoors is recommended for pollen allergy sufferers, but does not grant the absence of pollen or the total avoidance of symptoms. Results indicate that persons concerned should keep in mind being confronted with pollen in certain amounts throughout the year indoors in built environment.
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- 2017
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4. PalDat 3.0 – second revision of the database, including a free online publication tool
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Martina Weber and Silvia Ulrich
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0106 biological sciences ,0301 basic medicine ,Database ,Plant Science ,Biology ,medicine.disease_cause ,computer.software_genre ,Data submission ,01 natural sciences ,Second revision ,03 medical and health sciences ,Identification (information) ,030104 developmental biology ,Pollen ,Plant species ,medicine ,computer ,Ecology, Evolution, Behavior and Systematics ,010606 plant biology & botany - Abstract
PalDat is the world’s most comprehensive pollen database. At present, the database provides about 22 000 pollen pictures from more than 2500 plant species. Each dataset includes a detailed description of the pollen grain, light- and electron-microscopy images of the pollen grain, images of the plant/inflorescence/flower and relevant literature. Founded in 1997, PalDat had a major revision in 2015. The database contains tools for pollen identification and online publication. Online access to the database and data submission (www.paldat.org) are free of charge.
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- 2017
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5. Impact of eNOS-Dependent Oxidative Stress on Endothelial Function and Neointima Formation
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Nadine Nagy, Oliver Lieven, Stephanie Pick, Jens W. Fischer, Vu Thao-Vi Dao, Tatsiana Suvorava, Ulrich Rüther, Martina Weber, Georg Kojda, RS: CARIM - R3 - Vascular biology, Farmacologie en Toxicologie, and Pharmacology and Personalised Medicine
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Neointima ,Nitric Oxide Synthase Type III ,Endothelium ,Physiology ,Clinical Biochemistry ,medicine.disease_cause ,Biochemistry ,chemistry.chemical_compound ,Superoxides ,Enos ,Citrulline ,medicine ,Animals ,Humans ,Cysteine ,Molecular Biology ,Aorta ,General Environmental Science ,Mice, Knockout ,Neointimal hyperplasia ,Alanine ,biology ,Superoxide ,Myocardium ,Cell Biology ,biology.organism_classification ,medicine.disease ,Molecular biology ,Mice, Inbred C57BL ,Vasodilation ,Oxidative Stress ,Original Research Communications ,HEK293 Cells ,medicine.anatomical_structure ,chemistry ,General Earth and Planetary Sciences ,Cattle ,Endothelium, Vascular ,Peroxynitrite ,Oxidative stress - Abstract
Aims: Vascular oxidative stress generated by endothelial NO synthase (eNOS) was observed in experimental and clinical cardiovascular disease, but its relative importance for vascular pathologies is unclear. We investigated the impact of eNOS-dependent vascular oxidative stress on endothelial function and on neointimal hyperplasia. Results: A dimer-destabilized mutant of bovine eNOS where cysteine 101 was replaced by alanine was cloned and introduced into an eNOS-deficient mouse strain (eNOS-KO) in an endothelial-specific manner. Destabilization of mutant eNOS in cells and eNOS-KO was confirmed by the reduced dimer/monomer ratio. Purified mutant eNOS and transfected cells generated less citrulline and NO, respectively, while superoxide generation was enhanced. In eNOS-KO, introduction of mutant eNOS caused a 2.3–3.7-fold increase in superoxide and peroxynitrite formation in the aorta and myocardium. This was completely blunted by an NOS inhibitor. Nevertheless, expression of mutant eNOS in eNOS-KO completely restored maximal aortic endothelium-dependent relaxation to acetylcholine. Neointimal hyperplasia induced by carotid binding was much larger in eNOS-KO than in mutant eNOS-KO and C57BL/6, while the latter strains showed comparable hyperplasia. Likewise, vascular remodeling was blunted in eNOS-KO only. Innovation: Our results provide the first in vivo evidence that eNOS-dependent oxidative stress is unlikely to be an initial cause of impaired endothelium-dependent vasodilation and/or a pathologic factor promoting intimal hyperplasia. These findings highlight the importance of other sources of vascular oxidative stress in cardiovascular disease. Conclusion: eNOS-dependent oxidative stress is unlikely to induce functional vascular damage as long as concomitant generation of NO is preserved. This underlines the importance of current and new therapeutic strategies in improving endothelial NO generation. Antioxid. Redox Signal. 23, 711–723.
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- 2015
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6. Forensic value of pollen from ornamental indoor plants
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Philipp Nguyen and Martina Weber
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Forensic science ,Taxon ,Ecology ,Pollen ,Ornamental plant ,medicine ,Crime scene ,Forensic palynology ,Plant Science ,Biology ,medicine.disease_cause ,Ecology, Evolution, Behavior and Systematics - Abstract
Pollen is deposited almost everywhere and can be gathered and analysed. This work is part of a survey dedicated to indoor pollen from a forensic point of view. Ornamental plants were introduced into a private flat. Their influence on the pre-existing pollen assemblages was documented. Results show that ornamental plants can dramatically change the pollen spectra of indoor locations. The severity of this impact strongly varies with different plant taxa. These findings are important for forensic investigations, since such an ‘artificial’ pollen spectrum leaves an unusual trace and could subsequently relate a suspect to a crime scene.
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- 2015
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7. Metabolic Regulation of Pre- and Postnatal Growth
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Marie Standl, Joachim Heinrich, Olaf Uhl, Franca F. Kirchberg, Christian Hellmuth, Veit Grote, Elisabeth Thiering, Martina Weber, Hans Demmelmair, and Berthold Koletzko
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medicine.medical_specialty ,Pregnancy ,Insulin ,medicine.medical_treatment ,Birth weight ,CHOP ,Biology ,medicine.disease ,Insulin resistance ,Endocrinology ,Cord blood ,Internal medicine ,medicine ,Developmental plasticity ,medicine.symptom ,Weight gain - Abstract
Growth characteristics during periods of early developmental plasticity are linked with later health outcomes and with disease risks. Infant growth is modulated by genetic and exogenous factors including nutrition. We try to explore their underlying mechanisms using targeted metabolomic profiling of small molecules in biological samples using high-performance liquid chromatography (LC) coupled to tandem mass spectrometry (MS/MS) to quantify hundreds of molecules in small biosamples, e.g., 50 µL plasma. In the large German LISA birth cohort study, cord blood lysophosphatidylcholines and fatty acids were closely associated with infant birth weight, with a nonsignificant trend towards an association with infant weight gain and later BMI. Studies in infants randomized to different protein intakes in the European CHOP Study show conventional high protein intakes to markedly increase plasma-indispensable amino acids (AA), particularly branched-chain AA (BCAA), while exceeding the infant's capacity of BCAA breakdown, and an increase in the dispensable AA tyrosine previously associated with insulin resistance. In a path model analysis of the relationship of infant plasma AA, growth factors, and infant growth, AA were generally found to induce a stronger response of insulin than IGF-I although effects of individual AA were very different. We conclude that targeted improvement in nutrient supply in pregnancy and infancy may offer large opportunities for promoting desirable child growth patterns and long-term health.
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- 2018
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8. How to Describe and Illustrate Pollen Grains
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Michael Hesse, Friðgeir Grímsson, Silvia Ulrich, Ralf Buchner, Reinhard Zetter, Martina Weber, Andrea Frosch-Radivo, Matthias Svojtka, and Heidemarie Halbritter
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Magnoliids ,biology ,Pollen ,Botany ,medicine ,Commelinids ,biology.organism_classification ,Eudicots ,medicine.disease_cause ,Aperture (botany) ,Pinales ,Pollen wall - Abstract
For the description of a pollen grain, a number of features are used including size, polarity and shape, aperture condition, ornamentation, and pollen wall structure. Additional and often more specialized features depend on the group of plants under study, Gymnosperms (Cycadales, Ginkgoales, Pinales, Gnetales) vs. Angiosperms (magnoliids, monocots, commelinids, eudicots). These features can only be obtained by the application of a combined analysis with LM, SEM, and TEM (Fig. 1). In order to compare and categorize pollen, a common language and understanding of technical terms is necessary.
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- 2018
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9. Pollen Morphology and Ultrastructure
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Heidemarie Halbritter, Friðgeir Grímsson, Michael Hesse, Reinhard Zetter, Matthias Svojtka, Martina Weber, Ralf Buchner, Silvia Ulrich, and Andrea Frosch-Radivo
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0106 biological sciences ,Pollen ,Botany ,medicine ,Ultrastructure ,Biology ,medicine.disease_cause ,010603 evolutionary biology ,01 natural sciences ,Pollen wall ,010606 plant biology & botany - Abstract
The study of pollen should encompass all structural and ornamental aspects of the grain. Pollen morphology is studied using LM and SEM and is important to visualize the general features of a pollen grain, including, e.g., symmetry, shape, size, aperture number and location, as well as ornamentation. TEM investigations are used to highlight the stratification and the uniqueness of pollen wall layers as well as cytoplasmic features. The following sections explain the most important structural and sculptural pollen features a palynologist should observe.
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- 2018
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10. Pollen- and Dispersal Units
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Michael Hesse, Friðgeir Grímsson, Matthias Svojtka, Martina Weber, Reinhard Zetter, Silvia Ulrich, Ralf Buchner, Andrea Frosch-Radivo, and Heidemarie Halbritter
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Ecology ,Pollen ,medicine ,Biological dispersal ,Biology ,medicine.disease_cause - Published
- 2018
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11. Monitoring indoor pollen over two years
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Philipp Preusche and Martina Weber
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Palynology ,Ecology ,Plant Science ,Vegetation ,Biology ,medicine.disease_cause ,Domestic environment ,Agronomy ,Flowering season ,Pollen ,Ornamental plant ,medicine ,Ecology, Evolution, Behavior and Systematics ,Urban environment - Abstract
The present study monitored a private apartment for pollen that had settled on the floor. Pollen was sampled and analysed from two rooms over a period of two years. The study showed that pollen accumulations indoors are dominated by wind-pollinated species reflecting the current flowering season. The adjacent vegetation and the cleaning activities influenced the pollen content. Pollen from zoophilous plants mostly originated from ornamental plants within the flat. Similarities and differences between the two rooms and the two years were observed. These findings have implications for forensic investigations as well as allergological research.
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- 2014
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12. The unique design of pollen tetrads inDionaeaandDrosera
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Michael Hesse, Heidemarie Halbritter, and Martina Weber
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biology ,Drosera ,Operculum (botany) ,Plant Science ,Anatomy ,biology.organism_classification ,medicine.disease_cause ,Pollen ,Botany ,medicine ,Pollen tube ,Droseraceae ,Ecology, Evolution, Behavior and Systematics ,Pollen wall - Abstract
The heteropolar pollen grains of Dionaea and Drosera (Droseraceae) are united into permanent tetrads. Dionaea and Drosera tetrads have unique, complex internal set-ups. In both genera, apertures (pores) are situated equatorially (stephanoporate); neither Dionaea nor Drosera can be designated as examples for proximal polar situated apertures. In turgescent state, the tetrads show protrusions along the borders of adjoining pollen grains, which are enclosed by a thick intine and emerge from the apertures. One of these protrusions finally forms the pollen tube during germination. Both genera produce Ubisch bodies. In Drosera, the distal pollen wall above the apertures of each monad invaginates towards the centre of the pollen grain, forming an incomplete septum with a central opening. This septum divides the pollen grain into a larger distal and a smaller proximal chamber containing cytoplasm. In the literature, the septal opening was erroneously addressed as aperture (‘pore’). The proximal chambers ...
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- 2012
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13. The endexine: a frequently overlooked pollen wall layer and a simple method for detection
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Martina Weber and Silvia Ulrich
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Transmission electron microscopy ,Pollen ,medicine ,Biophysics ,Ultrastructure ,Plant Science ,Anatomy ,Biology ,medicine.disease_cause ,Layer (electronics) ,Ecology, Evolution, Behavior and Systematics ,Pollen wall ,Staining - Abstract
For the detection of pollen wall layers, the use of different staining methods for one and the same species is highly recommended. The usage of standard transmission electron microscopy (TEM) staining methods showed that the ektexine-layers have always the same contrast behaviour, while the endexine changes its electron opaqueness depending on the method used. However, the endexine can often not be discriminated from the other wall layers. A simple method to detect the endexine is the use of potassium permanganate, which stains the layer electron dense, producing a distinct contrast.
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- 2010
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14. Unique aperture stratification in Carex (Cyperaceae) pollen
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Michael Hesse, Martina Weber, and Heidemarie Halbritter
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Foot layer ,Carex ,Homogeneous ,Pollen ,Botany ,medicine ,Stratification (water) ,Plant Science ,Cyperaceae ,Biology ,medicine.disease_cause ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics - Abstract
Mature pollen usually has a conspicuously thick intine in the aperture regions, whereas in the interapertural area(s) the intine is thin. In Carex (and in other Cyperaceae with pseudomonads), usually five to six circular or elongated apertures (poroids) are present, one situated distally and the others equatorially. In the species studied here the situation is opposite: the apertures (poroids) are characterised by a very thin intine, whereas in the interapertural area(s) the intine is conspicuously thickened. A similar condition is only known for Vinca (Apocynaceae). A second unusual sporoderm feature in Carex relates to the foot layer. In the interapertural area(s) the foot layer is thin and discontinuous. The equatorial poroids exhibit a compact, thick and homogeneous foot layer, whereas the distal poroid is distinguished by an elaborated foot layer, structurally similar to a transfer-cell wall labyrinth. This unique elaborated foot layer in the distal poroid probably functions as a nutrimental...
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- 2010
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15. Beschorneria yuccoides and Asimina triloba (L.) Dun: Examples for proximal polar germinating pollen in angiosperms
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Heidemarie Halbritter, Martina Weber, and Michael Hesse
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biology ,Asimina ,Plant Science ,Anatomy ,medicine.disease_cause ,biology.organism_classification ,Foot layer ,Reticulate ,Microspore ,Pollen ,Botany ,medicine ,Pollen tube ,Beschorneria ,Ecology, Evolution, Behavior and Systematics ,Aperture (botany) - Abstract
Beschorneria yuccoides (Agavaceae) microspores are arranged mostly in planar tetrads. Later on, the pollen grains of the tetrad usually fall apart, but sometimes remain loosely connected by ektexine elements. The ektexine consists of a tectum, of short columellae, and of a thin, discontinuous foot layer. An endexine is absent. The bilayered intine is without any additional thickening that would usually indicate an aperture region. From this point of view the pollen grain might be considered as omniaperturate. The pollen ornamentation is reticulate with wide lumina and robust, smooth muri. The pollen grains show an indistinct sulcus characterised by a loose reticulate ornamentation. The sulcus is not exactly at the distal pole, but shifted towards the equator. No pollen tubes are formed regularly at the sulcus. Instead, pollen tubes are normally formed at the proximal pollen face. The proximal area, indicating a large germination field, is morphologically and functionally clearly an aperture (a ge...
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- 2009
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16. Diversity of essential oil glands of clary sage (Salvia sclarea L., Lamiaceae)
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Paolo Grassi, Johannes Novak, Corinna Schmiderer, Martina Weber, and Chlodwig Franz
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Chromatography, Gas ,Plant Science ,Biology ,Linalyl acetate ,Calyx ,law.invention ,chemistry.chemical_compound ,Linalool ,law ,Botany ,Oils, Volatile ,Plant Oils ,Salvia sclarea ,Salvia ,Ecology, Evolution, Behavior and Systematics ,Essential oil ,Sclareol ,Solid Phase Extraction ,fungi ,food and beverages ,General Medicine ,biology.organism_classification ,Terpenoid ,chemistry ,Microscopy, Electron, Scanning ,Lamiaceae - Abstract
The Lamiaceae is rich in aromatic plant species. Most of these species produce and store essential oils in specialised epidermal oil glands, which are responsible for their specific flavour. Two types of glands producing essential oil and possessing different morphological structure can be found in Salvia sclarea: peltate and capitate glands. The content of single oil glands from different positions on the plant (corolla, calyx and leaf) were sampled using an SPME fibre and analysed by gas chromatography in order to study variability of the essential oil composition. It was found that the composition of terpenoids is quite variable within an individual plant. Capitate oil glands mainly produce three essential oil compounds: the monoterpenes linalool and linalyl acetate, and the diterpene sclareol. Peltate oil glands, however, accumulate noticeable concentrations of sesquiterpenes and an unknown compound (m/z = 354). Furthermore, the oil composition varies within each gland type according to the plant organ. Linalool and linalyl acetate are characteristic substances of flowers, whereas the sesquiterpenes occur in higher proportions in leaves. Even within one gland type on a single leaf, the chemical variability is exceedingly high.
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- 2008
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17. Virus-like particle formation and translational start site choice of the plant retrotransposon Tto1
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Gudrun Böhmdorfer, Martina Weber, Andrea Tramontano, Andrea Frosch, Karin Garber, Srecko Jelenic, Kerstin Luxa, and Andreas Bachmair
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0106 biological sciences ,DNA, Plant ,Retroelements ,viruses ,Molecular Sequence Data ,Arabidopsis ,Retrotransposon ,Biology ,Inducible retrotransposon ,01 natural sciences ,Plant Viruses ,03 medical and health sciences ,Open Reading Frames ,Eukaryotic translation ,Virus-like particle ,Virology ,Translation initiation ,Tobacco ,Protein biosynthesis ,reverse transcription ,virus-like particles ,Peptide Chain Initiation, Translational ,Promoter Regions, Genetic ,Gene ,030304 developmental biology ,DNA Primers ,Genetics ,0303 health sciences ,Base Sequence ,Genetic Complementation Test ,Virion ,RNA ,Reverse transcription ,Group-specific antigen ,Virus-like particles ,Plants ,Plants, Genetically Modified ,Genes, gag ,Genes, pol ,Open reading frame ,Protein Biosynthesis ,DNA, Viral ,010606 plant biology & botany - Abstract
Ty1/copia group retrotransposon Tto1 from tobacco was put under control of an inducible promoter for expression in Arabidopsis thaliana. The system was used to analyze intermediates of the transposition process. The Tto1 RNA 5′ region has a complex structure and contains several AUG codons. We therefore sought to experimentally define the translation initiation site. Constructs starting at various positions within the structural gag region were expressed in planta and functionally characterized. We found that gag proteins starting at the first ATG of the gag-pol ORF (ATG1), but also those starting at the third ATG of the gag-pol ORF (ATG3), can form virus-like particles (VLPs). However, gag protein expressed by the inducible Tto1 element had a size similar to gag starting at ATG1, and mutation of ATG1 in the inducible element abolished reverse transcription. This suggested that translation initiation at ATG1 is essential for the Tto1 life cycle. To support this conjecture, gag protein starting at ATG1, or gag protein shortened amino-terminally by nine amino acids (starting at the second ATG of the gag region, ATG2), was co-expressed with Tto1 carrying mutations at ATG1 and ATG2. Trans-complementation of the defective Tto element by gag starting at ATG1, but not by gag starting at ATG2, defines ATG1 as the functional translation initiation site.
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- 2008
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18. Statin Treatment and 3′ Polyadenylation of eNOS mRNA
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Jeffrey P Moore, Ioanna Kosmidou, Martina Weber, and Charles D. Searles
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rho GTP-Binding Proteins ,Cytoplasm ,Simvastatin ,Cytochalasin D ,Time Factors ,Nitric Oxide Synthase Type III ,Polyadenylation ,Cytoskeleton organization ,RNA Stability ,Gene Expression Regulation, Enzymologic ,MRNA polyadenylation ,Enos ,Animals ,RNA, Messenger ,Phosphorylation ,Rosuvastatin Calcium ,Cells, Cultured ,Cytoskeleton ,Cell Nucleus ,Sulfonamides ,Messenger RNA ,Dose-Response Relationship, Drug ,biology ,Tumor Necrosis Factor-alpha ,Endothelial Cells ,nutritional and metabolic diseases ,RNA 3' Polyadenylation Signals ,biology.organism_classification ,Actin cytoskeleton ,Molecular biology ,Cell Hypoxia ,Fluorobenzenes ,Nitric oxide synthase ,Pyrimidines ,HMG-CoA reductase ,biology.protein ,Cattle ,lipids (amino acids, peptides, and proteins) ,RNA Polymerase II ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,Cardiology and Cardiovascular Medicine - Abstract
Objective— Statins have been shown to increase endothelial nitric oxide synthase expression via enhanced mRNA stability. Because the poly(A) tail is an important determinant of transcript stability, we sought to characterize the effect of statins on eNOS mRNA 3′ polyadenylation. Methods and Results— Endothelial cells treated with statins had a time- and dose-dependent increase in eNOS transcripts with long poly(A) tails (75 to 160 adenosines). This effect was dependent on 3-hydroxy-3-methylglutaryl (HMG)-coenxyme A (CoA) reductase inhibition and was observed with both lipophilic (simvastatin) and hydrophilic (rosuvastatin) statins. In mRNA stability assays, polyadenylated eNOS transcripts from statin-treated cells were 2- to 3-fold more stable than transcripts from untreated cells. The effect of statins on eNOS polyadenylation was related to cytoskeleton organization; there was increased eNOS mRNA polyadenylation after Rho inhibition and cytochalasin D treatment. Further, we found increased phosphorylation of RNA polymerase II in statin-treated cells, suggesting that statin-induced polyadenylation involved modulation of RNA polymerase II activity. Conclusions— Our data provide insight into a mechanism by which statins enhance eNOS mRNA stability and increase eNOS protein: statins increase eNOS mRNA polyadenylation through Rho-mediated changes in the actin cytoskeleton.
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- 2007
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19. Walls of allergenic pollen: Special reference to the endexine
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Bernadette Diethart, Saskia Sam, and Martina Weber
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Betulaceae ,biology ,food and beverages ,Plant Science ,respiratory system ,medicine.disease ,biology.organism_classification ,medicine.disease_cause ,respiratory tract diseases ,Ulmaceae ,immune system diseases ,Germination ,Pollen ,Botany ,otorhinolaryngologic diseases ,medicine ,Hay fever ,Poaceae ,Ecology, Evolution, Behavior and Systematics ,Ambrosia artemisiifolia ,Pollen wall - Abstract
Allergic rhinitis is an increasing health problem and pollen allergens are amongst the main elicitors of hay fever symptoms. Allergenic pollen contains a set of differently allergenic proteins which are thought to play a role in the pollen germination and fertilisation process. They are released upon contact with the stigma or mucosa or upon pollen grain rupture. Although the determinants of allergenicity of these proteins are still largely undiscovered, accessibility and solubility are now thought to mainly influence allergenic potency. Pollen of 61 allergenic plants was investigated with scanning and transmission electron microscopy. Most of the minor allergenic plants like species of the families Salicaceae, Fagaceae or Ulmaceae show the typical pollen wall organisation with intine, compact endexine and ektexine whereas in the majority of the major allergenic plants like species of Betulaceae and Poaceae the endexine is not detectable. Ambrosia artemisiifolia exhibits a laminated endexine. In addition,...
- Published
- 2007
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20. Exploding pollen in Montrichardia arborescens (Araceae)
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Heidemarie Halbritter and Martina Weber
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Tube formation ,Montrichardia ,Pollination ,Plant Science ,Biology ,medicine.disease_cause ,biology.organism_classification ,Pollinator ,Pollen ,Botany ,medicine ,Pollen tube ,Ecology, Evolution, Behavior and Systematics ,Aperture (botany) ,Pollen wall - Abstract
Pollen grains of Montrichardia are inaperturate with psilate ornamentation. The pollen wall is formed by a thin ectexine and an extraordinarily thick intine. In living as well as in dead pollen grains contact with water leads to a rapid swelling of the intine followed by an explosive opening of the exine. Within a few seconds a thick tube is formed, which is not the pollen tube. The pollen protoplast is situated at the tip of the tube. These intine tubes are interpreted as pollen connecting tools to keep pollen grains together and adhere them to the cuticle of the hairless pollinators.
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- 2006
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21. Proteomic Characterization of the Angiogenesis Inhibitor SU6668 Reveals Multiple Impacts on Cellular Kinase Signaling
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Axel Ullrich, György Kéri, Laszlo Orfi, Klaus Godl, Zoltán Horváth, Heidrun Degen, Martina Weber, Matthew Cotten, Oliver J. Gruss, Stefan Müller, Henrik Daub, Dirk Brehmer, Jan Eickhoff, Josef Wissing, and Stephanie Blencke
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Cancer Research ,Indoles ,Aurora inhibitor ,Angiogenesis Inhibitors ,Protein Serine-Threonine Kinases ,Transfection ,Receptor tyrosine kinase ,MAP2K7 ,Aurora kinase ,Aurora Kinases ,Chlorocebus aethiops ,Animals ,Humans ,Pyrroles ,ASK1 ,Protein Kinase Inhibitors ,MAPK14 ,biology ,Cyclin-dependent kinase 4 ,Cyclin-dependent kinase 2 ,Oxindoles ,Cell biology ,Oncology ,Biochemistry ,COS Cells ,biology.protein ,Propionates ,Cell Division ,HeLa Cells - Abstract
Knowledge about molecular drug action is critical for the development of protein kinase inhibitors for cancer therapy. Here, we establish a chemical proteomic approach to profile the anticancer drug SU6668, which was originally designed as a selective inhibitor of receptor tyrosine kinases involved in tumor vascularization. By employing immobilized SU6668 for the affinity capture of cellular drug targets in combination with mass spectrometry, we identified previously unknown targets of SU6668 including Aurora kinases and TANK-binding kinase 1. Importantly, a cell cycle block induced by SU6668 could be attributed to inhibition of Aurora kinase activity. Moreover, SU6668 potently suppressed antiviral and inflammatory responses by interfering with TANK-binding kinase 1–mediated signal transmission. These results show the potential of chemical proteomics to provide rationales for the development of potent kinase inhibitors, which combine rather unexpected biological modes of action by simultaneously targeting defined sets of both serine/threonine and tyrosine kinases involved in cancer progression.
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- 2005
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22. Laminar Shear Stress and 3′ Polyadenylation of eNOS mRNA
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Charles D. Searles, Martina Weber, David G. Harrison, and Curt H. Hagedorn
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Simvastatin ,Nitric Oxide Synthase Type III ,Transcription, Genetic ,Translational efficiency ,Polyadenylation ,Physiology ,RNA Stability ,Biology ,Polymerase Chain Reaction ,Gene Expression Regulation, Enzymologic ,Enos ,Polysome ,Gene expression ,Protein biosynthesis ,Animals ,RNA, Messenger ,Cells, Cultured ,Messenger RNA ,Hydrogen Peroxide ,biology.organism_classification ,Molecular biology ,Nitric oxide synthase ,Protein Biosynthesis ,biology.protein ,Cattle ,Stress, Mechanical ,Nitric Oxide Synthase ,Shear Strength ,Cardiology and Cardiovascular Medicine - Abstract
The 3′ poly(A) tail is important in messenger RNA stability and translational efficiency. In somatic tissues, 3′ polyadenylation of mRNAs has been thought to largely be a constitutively active process. We have reported that laminar shear stress causes a brief increase in endothelial nitric oxide synthase (eNOS) transcription, followed by a prolonged increase in eNOS mRNA stability. We sought to determine whether shear stress and other stimuli affected eNOS 3′ polyadenylation in endothelial cells. Under basal (static) conditions, eNOS mRNA possessed short 3′ poly(A) tails of
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- 2005
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23. Actin Cytoskeleton Organization and Posttranscriptional Regulation of Endothelial Nitric Oxide Synthase During Cell Growth
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Lucienne M. Ide, Michael Davis, Hua Cai, Martina Weber, and Charles D. Searles
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Nitric Oxide Synthase Type III ,Physiology ,RNA Stability ,macromolecular substances ,Filamentous actin ,Gene Expression Regulation, Enzymologic ,Actin cytoskeleton organization ,Enos ,Depsipeptides ,Animals ,RNA, Messenger ,Cytoskeleton ,3' Untranslated Regions ,Cells, Cultured ,Actin ,Cell Proliferation ,Binding Sites ,biology ,Microfilament Proteins ,Actin cytoskeleton ,biology.organism_classification ,Molecular biology ,Actins ,Cell biology ,Nitric oxide synthase ,Endothelial stem cell ,Actin Cytoskeleton ,Ribonucleoproteins ,biology.protein ,Cattle ,Marine Toxins ,Endothelium, Vascular ,Nitric Oxide Synthase ,Cardiology and Cardiovascular Medicine - Abstract
Posttranscriptional regulation of endothelial nitric oxide synthase (eNOS) expression is an important mechanism by which endothelial cells respond to various physiological and pathophysiological stimuli. Previously, we showed that eNOS expression was dramatically altered by the state of cell growth and that the mechanism responsible for this regulation was entirely posttranscriptional, occurring via changes in eNOS mRNA stability. The present study identifies a role for actin cytoskeleton organization in the posttranscriptional regulation of eNOS during cell growth and examines the relationship between the state of actin polymerization and eNOS expression. We identified monomeric actin (globular [G]-actin) as the major component of a 51-kDa ribonucleoprotein that binds to the eNOS mRNA 3′ untranslated region in UV-crosslinking analysis. Binding activity of the ribonucleoprotein complex correlated with the relative concentration of G-actin versus filamentous actin (F-actin). ENOS transcripts colocalized with cytoplasmic G-actin in cells subjected to fluorescence in situ hybridization and G-actin fluorescence staining. In subcellular fractionation studies, eNOS transcripts were enriched in the free polysomal fraction of nonproliferating cells and enriched in the cell matrix-associated polysomal fraction of proliferating cells. Furthermore, an inverse relationship between the concentration of G-actin and eNOS expression was observed in endothelial cells subjected to pharmacological alteration of their cytoskeleton; lower G/F-actin ratios correlated with increased eNOS expression. Our findings provide some insight into how endothelial cells may use the dynamic organization of the actin cytoskeleton to regulate expression of an enzyme that is crucial to vascular homeostasis.
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- 2004
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24. Oscillatory shear stress upregulation of endothelial nitric oxide synthase requires intracellular hydrogen peroxide and CaMKII*1
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Martina Weber, Joseph S McNally, Hua Cai, and David G. Harrison
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medicine.medical_specialty ,biology ,Chemistry ,Superoxide ,Nitric Oxide Synthase Type III ,biology.organism_classification ,Cell biology ,chemistry.chemical_compound ,Endocrinology ,Downregulation and upregulation ,Enos ,Internal medicine ,Ca2+/calmodulin-dependent protein kinase ,medicine ,Phosphorylation ,Cardiology and Cardiovascular Medicine ,Molecular Biology ,Intracellular ,Peroxynitrite - Abstract
We have previously shown that hydrogen peroxide (H 2 O 2 ) upregulates endothelial nitric oxide synthase (eNOS) expression via a calcium/calmodulin-dependent protein kinase II (CaMKII)-mediated mechanism whereas it also acutely activates eNOS enzyme. We hypothesized that oscillatory shear stress (OSS), which stimulates endogenous H 2 O 2 , would have effects on eNOS expression and function similar to that of exogenous H 2 O 2 . Exposure of bovine aortic endothelial cells to OSS (±15 dynes/cm 2 ) increased eNOS mRNA expression by 3-fold. Pretreatment with either polyethylene glycol-catalase (PEG-CAT, a scavenger of H 2 O 2 ) or KN93, an inhibitor of CaMKII, abolished this response. OSS activated CaMKII in an H 2 O 2 -dependent fashion whereas unidirectional laminar shear stress (LSS) inhibited CaMKII phosphorylation. Inhibition of c-Src (essential for LSS upregulation of eNOS) had no effect on OSS upregulation of eNOS. Additionally, OSS stimulated NO • production acutely. Scavenging of H 2 O 2 by PEG-CAT attenuated OSS stimulation of NO • by 50% whereas it had no effect on LSS regulation of NO • production. These data suggest that intracellular H 2 O 2 and CaMKII mediate OSS upregulation of eNOS. The acute activation of eNOS by OSS also partially requires H 2 O 2 . As OSS has been shown previously to stimulate sustained production of superoxide (O 2 •– ) which would inactivate NO • , these responses may represent attempted compensation to restore NO • bioavailability in areas exposed to OSS. Simultaneous stimulation of O 2 •– and NO • by this mechanism, however, could facilitate peroxynitrite formation and protein nitration, which may enhance atherosclerotic lesion formation. Both OSS and LSS upregulate eNOS expression but via different signaling mechanisms.
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- 2004
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25. The effect of hypercholesterolemia on platelet soluble guanylyl cyclase
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Martina Weber, Eva Kottenberg-Assenmacher, and Georg Kojda
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Blood Platelets ,medicine.medical_specialty ,Platelet Aggregation ,Arteriosclerosis ,Physiology ,Hypercholesterolemia ,Receptors, Cytoplasmic and Nuclear ,Aorta, Thoracic ,Nitric Oxide ,Nitric oxide ,chemistry.chemical_compound ,Soluble Guanylyl Cyclase ,Internal medicine ,medicine ,Animals ,Nitric Oxide Donors ,Platelet ,Aorta, Abdominal ,Cyclic GMP ,Pharmacology ,Lagomorpha ,biology ,Platelet Count ,Cholesterol ,Penicillamine ,Snap ,Radioimmunoassay ,biology.organism_classification ,Endocrinology ,Solubility ,chemistry ,Mechanism of action ,Guanylate Cyclase ,Molecular Medicine ,Rabbits ,medicine.symptom ,Tunica Intima ,Soluble guanylyl cyclase - Abstract
We sought to determine whether hypercholesterolemia impacts on the NO-stimulated activity of platelet soluble guanylyl cyclase (sGC). We investigated two groups of nine New Zealand white rabbits receiving either a standard (NC) or a cholesterol chow (HC, 0.75%) for 15 weeks. The plasma content of cGMP and the specific activity of sGC in intact platelets were measured by a cGMP-specific radioimmunoassay. In HC, 47.9+/-3.1% of the aortic intimal area was covered with atherosclerotic lesions, and plasma cGMP levels (pmol/ml) were increased from 12.6+/-1.2 to 27.9+/-3.5 (P
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- 2003
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26. Diethyldithiocarbamate inhibits the catalytic activity of xanthine oxidase
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Martina Weber, Ilona König, Thorsten Kober, and Georg Kojda
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Male ,Xanthine Oxidase ,Epinephrine ,Biophysics ,6-Anilino-5,8-quinolinedione ,Xanthine ,Biochemistry ,Catalysis ,Superoxide dismutase ,chemistry.chemical_compound ,Superoxides ,Structural Biology ,Oxidoreductase ,Soluble guanylyl cyclase ,Culture Techniques ,Genetics ,Animals ,Lucigenin ,Enzyme Inhibitors ,Rats, Wistar ,Xanthine oxidase ,Molecular Biology ,Aorta ,chemistry.chemical_classification ,biology ,Chemistry ,Superoxide ,Snap ,Cell Biology ,Rats ,Enzyme ,Guanylate Cyclase ,Diethyldithiocarbamate ,Aminoquinolines ,biology.protein ,Ditiocarb ,Oxidation-Reduction - Abstract
We sought to determine the effects of the superoxide dismutase (SOD) inhibitor diethyldithiocarbamate (DETC) on vascular superoxide production. Rat aortic rings treated with DETC (10 mM) showed no change of superoxide generation (5 μM lucigenin). Likewise, DETC did not change the expression and activity of vascular soluble guanylyl cyclase, an enzyme known to be extremely sensitive to superoxide. In striking contrast, DETC completely inhibited the superoxide production induced by 6-anilino-5,8-quinolinedione (LY83583) and abolished the catalytic activity of xanthine oxidase (XO). Thus, DETC inhibits vascular superoxide production by blocking oxidoreductase enzymes such as XO and those reducing LY83583 in rat aorta.
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- 2003
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27. Pollen, Pollenkitt, and Orbicules in Craigia bronnii Flower Buds (Tilioideae, Malvaceae) from the Miocene of Hambach, Germany
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Reinhard Zetter, M. Pingen, Martina Weber, and Michael Hesse
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biology ,food and beverages ,Craigia ,Plant Science ,biology.organism_classification ,medicine.disease_cause ,Tilioideae ,Foot layer ,Extant taxon ,Tilia ,Pollen ,Botany ,medicine ,Ecology, Evolution, Behavior and Systematics ,Malvaceae - Abstract
Well‐preserved polliniferous flower buds from the Upper Miocene Inden Beds (Hambach lignite, Lower Rhenish Basin, Germany) were studied by scanning electron and transmission electron microscopy techniques. The Craigia bronnii flower buds are in many respects very similar to those of extant Tilioideae (Malvaceae). The in situ pollen strongly resembles fossil Craigia and recent Tilia pollen, respectively. Especially features of the endexine and the foot layer in the apertural areas and the idiomatic reticulum, including the peculiar mode of branching columellae, are highly similar. Amorphous, highly electron‐dense substances (pollenkitt) and orbicules, which are both likewise highly similar to those of recent Tilia, are present between and on the pollen grains of the flower buds. There is evidence from staining and sectioning behavior of this amorphous substance that it in fact represents pollenkitt.
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- 2002
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28. Club-Shaped Organs as Additional Osmophores within the Sauromatum Inflorescence: Odour Analysis, Ultrastructural Changes and Pollination Aspects1
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F. Hadacek and Martina Weber
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biology ,Pollination ,Plant Science ,General Medicine ,biology.organism_classification ,Araceae ,Sauromatum ,chemistry.chemical_compound ,Inflorescence ,Linalool ,chemistry ,Pollinator ,Botany ,Ultrastructure ,Spadix (botany) ,Ecology, Evolution, Behavior and Systematics - Abstract
Gradient odour emissions in the inflorescence of the Araceae Sauromatum guttatum aim to attract a wide range of insects into the floral chamber. The volatiles are emitted from the spadix appendix, as well as the club-shaped organs located directly above the female flowers. Volatile analysis of various regions of the appendix and the club-shaped organs led to the identification of 163 compounds emitted by the appendix top, 124 by the appendix bottom and 105 by the club-shaped organs. The dominant compounds in all investigated tissues were monoterpenes and sesquiterpenes that were accompanied by numerous aliphatic, aromatic, sulphur- and nitrogen-containing compounds of other biosynthetic origins. Within the appendix, levels of one monoterpene, β-citronellene, showed considerable variation; it constituted the major compound in the appendix top and gradually decreased in the lower regions, being undetectable in the base. The other prominent monoterpenes, α-pinene, β-pinene, limonene, α-phellandrene and β-phellandrene, showed no changes along the appendix. The club-shaped organs located at the base of the floral chamber also emitted volatiles, though of different composition: the monoterpenes α-terpinolene and linalool constituted major amounts, instead of β-pinene and β-citronellene. These qualitative differences and the absence of methanethiol in the club-shaped organs result in them having a pleasant flowery odour, in contrast to the foul-smelling appendix. The quantitative spatial variation of β-citronellene within the appendix and the existence of a second osmophore within the floral chamber, emitting a different scent, suggest that both phenomena might participate in creating an odour gradient for efficient pollinator attraction. Apart from β-citronellene, nearly all major components of the appendix have already been identified as specific attractants to a broad range of insects that have been observed to be lured to the odour-emitting inflorescence. Most likely, the club-shaped organ odour serves to induce the insects attracted by the appendix to move towards the floral chamber. A comparison of the relative emission rates demonstrated that performance of the club-shaped organs equals or even exceeds the appendix. In the club-shaped organ tissues, multivesicular bodies, originating from lipid droplets, are the most notable organelles before and during odour production. They fuse with the plasma membrane, releasing their content to the exterior of the cell. The exit route for the volatiles is an extensive intercellular channel system that extends to the surface of the club-shaped organs. Thus, chemical and ultrastructural analyses suggest, in contrast to previous studies, that the club-shaped organs function as an osmophore rather than a food source for insects.
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- 2002
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29. Olfactory receptor expressed in ganglia of the autonomic nervous system
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Martina Weber, Jörg Strotmann, Ulrich Pehl, and Heinz Breer
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Olfactory system ,Pathology ,medicine.medical_specialty ,Population ,Gene Expression ,Mice, Transgenic ,Biology ,Receptors, Odorant ,Mice ,Cellular and Molecular Neuroscience ,Harderian gland ,Nerve Fibers ,medicine ,Animals ,Tissue Distribution ,Thoracic ganglia ,education ,Ganglia, Autonomic ,education.field_of_study ,Olfactory receptor ,Brain ,Nasal glands ,Thorax ,Autonomic nervous system ,medicine.anatomical_structure ,Olfactory ensheathing glia ,Neck - Abstract
Certain members of the olfactory receptor superfamily appear to be expressed not only in chemosensory neurons of the nasal epithelium. Analyzing the transgenic mouse line MOL2.3-IGITL, the olfactory receptor subtype MOL2.3 was found to be expressed in distinct subpopulations of cells within a cranial, a cervical as well as within a thoracic ganglion. By means of coexpressed markers, the axonal processes of MOL2.3 expressing cells could be visualized and thus the target tissues innervated by these ganglionic neurons identified. Stained fibers, but no stained cell bodies were visible in distinct head regions, notably in the lateral nasal gland and in the so-called Harderian gland; staining was also observed on distinct segments of blood vessels, especially within the tongue. In the thoracic region, the heart and a small segment of the aorta as well as a distinct population of lung alveoli were labeled by incoming blue fibers. Expression of MOL2.3 in cells of the autonomic nervous system supports the idea that at least some of the multiple olfactory receptor types serve functions others than odorant detection.
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- 2002
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30. Tracking the Immunoregulatory Mechanisms Active During Allograft Tolerance
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Xin Xiao Zheng, Terry B. Strom, Alberto Sanchez-Fueyo, Martina Weber, and Christoph Domenig
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CD4-Positive T-Lymphocytes ,Graft Rejection ,Isoantigens ,Immunoconjugates ,T-Lymphocytes ,T cell ,Immunology ,Islets of Langerhans Transplantation ,chemical and pharmacologic phenomena ,Biology ,Lymphocyte Activation ,T-Lymphocytes, Regulatory ,Lymphocyte Depletion ,Abatacept ,Mice ,Interleukin 21 ,Antigens, CD ,medicine ,Animals ,Transplantation, Homologous ,Immunology and Allergy ,Cytotoxic T cell ,CTLA-4 Antigen ,IL-2 receptor ,Antigen-presenting cell ,Cells, Cultured ,Interleukin 3 ,Antibodies, Monoclonal ,CD28 ,Peripheral tolerance ,Receptors, Interleukin-2 ,Adoptive Transfer ,Antigens, Differentiation ,Cell biology ,medicine.anatomical_structure ,Mice, Inbred DBA ,Interleukin-2 ,Transplantation Tolerance ,Lymphocyte Culture Test, Mixed ,Spleen - Abstract
Immunoregulatory mechanisms dependent on regulatory CD4+ T cells are believed to be critical in the maintenance of peripheral tolerance to allografts. However, a detailed characterization of the effects of these regulatory T cells has been hampered by the absence of a simple means to track and study them. In this work we provide evidence that in a murine model of islet transplantation the interactions between alloaggressive and regulatory T cells can be studied in vitro and in vivo at the single-cell level. The observations made in both an in vitro coculture system and an in vivo CFSE-based adoptive transfer model indicate that lymphocytes from tolerant allograft recipients 1) proliferate weakly to donor strain allogeneic cells but vigorously to third-party strain cells; and 2) suppress the proliferation of naive syngeneic CD4+ and CD8+ T cells to donor tissue in a cell dose- and Ag-specific manner. These effects depend on the presence of CD4+CD25+ T cells and are neutralized by anti-CTLA4 mAb or rIL-2. The principal effect of anti-CTLA4 is directed against the naive, not regulatory, T cell population. These results can be replicated in vivo by transferring lymphocyte populations into transplant recipients, proving that the graft-protecting actions of regulatory T cells are blunted by a rise in the number of allodestructive T cells (pool size model) and depend on the presence of CD4+CD25+ T cells and the integrity of the CTLA4/B7 pathway.
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- 2002
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31. TNF-α alters the release and transfer of microparticle-encapsulated miRNAs from endothelial cells
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Warren D. Gray, Charles D. Searles, Martina Weber, Tamas Alexy, and Kimberly Rooney
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Caspase inhibitors ,rho-Associated Kinases ,biology ,Physiology ,Tumor Necrosis Factor-alpha ,Endothelial Cells ,MicroRNA ,Phenotype ,Caspase Inhibitors ,Cell-Derived Microparticles ,Cell biology ,MicroRNAs ,Caspases ,microRNA ,Immunology ,Genetics ,biology.protein ,Humans ,Tumor necrosis factor alpha ,Microparticle ,Caspase ,Aorta ,Extracellular RNA - Abstract
MicroRNAs (miRNAs) encapsulated within microparticles (MPs) are likely to have a role in cell-to-cell signaling in a variety of diseases, including atherosclerosis. However, little is known about the mechanisms by which different cell types release and transfer miRNAs. Here, we examined TNF-α-induced release of MP-encapsulated miR-126, miR-21, and miR-155 from human aortic endothelial cells (ECs) and their transfer to recipient cells. ECs were treated with TNF-α (100 ng/ml) in the presence or absence of inhibitors that target different MP production pathways. MPs released in response to TNF-α were characterized by: 1) 70–80% decrease in miRNA/MP levels for miR-126 and -21 but a significant increase in pre-miR-155 and miR-155 ( P < 0.05), 2) 50% reduction in uptake by recipient cells ( P < 0.05), and 3) diminished ability to transfer miRNA to recipient cells. Cotreatment of donor ECs with TNF-α and caspase inhibitor (Q-VD-OPH, 10 μM) produced MPs that had: 1) 1.5- to 2-fold increase in miRNA/MP loading, 2) enhanced uptake by recipient cells (2-fold), and 3) increased ability to transfer miR-155. Cotreatment of ECs with TNF-α and Rho-associated kinase (ROCK) inhibitor (10 μM) produced MPs with features similar to those produced by TNF-α treatment alone. Our data indicate that TNF-α induced the production of distinct MP populations: ROCK-dependent, miRNA-rich MPs that effectively transferred their cargo and were antiapoptotic, and caspase-dependent, miRNA-poor MPs that were proapoptotic. These data provide insight into the relationship between MP production and extracellular release of miRNA, as well as the potential of encapsulated miRNA for cell-to-cell communication.
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- 2014
32. Rapid growth and childhood obesity are strongly associated with lysoPC(14:0)
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Peter, Rzehak, Christian, Hellmuth, Olaf, Uhl, Franca F, Kirchberg, Wolfgang, Peissner, Ulrike, Harder, Veit, Grote, Martina, Weber, Annick, Xhonneux, Jean-Paul, Langhendries, Natalia, Ferre, Ricardo, Closa-Monasterolo, Elvira, Verduci, Enrica, Riva, Piotr, Socha, Dariusz, Gruszfeld, Berthold, Koletzko, and Melissa, Theurich
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Male ,Pediatrics ,medicine.medical_specialty ,Medicine (miscellaneous) ,Biology ,Child Nutritional Physiological Phenomena ,Weight Gain ,Childhood obesity ,law.invention ,Body Mass Index ,Cohort Studies ,Child Development ,Randomized controlled trial ,law ,Predictive Value of Tests ,Risk Factors ,Internal medicine ,medicine ,Humans ,Obesity ,Child ,Infant Nutritional Physiological Phenomena ,Nutrition and Dietetics ,Infant ,Lysophosphatidylcholines ,Overweight ,medicine.disease ,Diet ,Europe ,Endocrinology ,Early Diagnosis ,Predictive value of tests ,Female ,medicine.symptom ,Weight gain ,Body mass index ,Biomarkers ,Cohort study - Abstract
Background: Despite the growing interest in the early-origins-of-later-disease hypothesis, little is known about the metabolic underpinnings linking infant weight gain and childhood obesity. Objective: To discover biomarkers reflective of weight change in the first 6 months and overweight/obesity at age 6 years via a targeted metabolomics approach. Design: This analysis comprised 726 infants from a European multicenter randomized trial (Childhood Obesity Programme, CHOP) for whom plasma blood samples at age 6 months and anthropometric data up to the age of 6 years were available. ‘Rapid growth' was defined as a positive difference in weight within the first 6 months of life standardized to WHO growth standards. Weight change was regressed on each of 168 metabolites (acylcarnitines, lysophosphatidylcholines, sphingomyelins, and amino acids). Metabolites significant after Bonferroni's correction were tested as predictors of later overweight/obesity. Results: Among the overall 19 significant metabolites, 4 were associated with rapid growth and 15 were associated with a less-than-ideal weight change. After adjusting for feeding group, only the lysophosphatidylcholine LPCaC14:0 remained significantly associated with rapid weight gain (β = 0.18). Only LPCaC14:0 at age 6 months was predictive of overweight/obesity at age 6 years (OR 1.33; 95% CI 1.04-1.69). Conclusion: LPCa14:0 is strongly related to rapid growth in infancy and childhood overweight/obesity. This suggests that LPCaC14:0 levels may represent a metabolically programmed effect of infant weight gain on the later obesity risk. However, these results require confirmation by independent cohorts.
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- 2014
33. Protein intake in infancy and carotid intima media thickness at 5 years--a secondary analysis from a randomized trial
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Dariusz, Gruszfeld, Martina, Weber, Monika, Nowakowska-Rysz, Roman, Janas, Rainer, Kozlik-Feldmann, Annick, Xhonneux, Clotilde, Carlier, Enrica, Riva, Elvira, Verduci, Ricardo, Closa-Monasterolo, Joaquin, Escribano, Anna, Dobrzanska, Berthold, Koletzko, and F, Vecchi
- Subjects
Blood Glucose ,Male ,Pediatrics ,medicine.medical_specialty ,Low protein ,Medicine (miscellaneous) ,Blood Pressure ,Motor Activity ,Carotid Intima-Media Thickness ,Childhood obesity ,law.invention ,Body Mass Index ,Randomized controlled trial ,law ,Risk Factors ,medicine ,Humans ,Insulin ,cardiovascular diseases ,Insulin-Like Growth Factor I ,Infant Nutritional Physiological Phenomena ,Nutrition and Dietetics ,medicine.diagnostic_test ,biology ,Apolipoprotein A-I ,business.industry ,Infant, Newborn ,Infant ,medicine.disease ,Lipids ,Infant Formula ,Europe ,Breast Feeding ,Intima-media thickness ,Cardiovascular Diseases ,Child, Preschool ,Apolipoprotein B-100 ,cardiovascular system ,biology.protein ,Apolipoprotein A1 ,Female ,Dietary Proteins ,business ,Lipid profile ,Breast feeding ,Body mass index ,Follow-Up Studies - Abstract
Background: Nutrition in childhood has an influence on the cardiovascular function later on in life. European Childhood Obesity Project is a multicenter, randomized clinical intervention trial examining the effect of early protein intake on later health outcomes, particularly adiposity and related disorders. The aim of the study was to examine the effect of nutritional intervention - different protein intake in infancy on carotid intima-media thickness (cIMT) at 5 years. The association of cardiovascular risk factors with cIMT was also assessed. Methods: Healthy term formula-fed infants in five European countries were enrolled either to the higher (HP) or to the lower (LP) protein group. Observational group consisted of breastfed infants. Plasma insulin, glucose, lipid profile, IGF-1, apolipoprotein A1 and B were measured as well as anthropometric parameters of parents and a child, blood pressure and physical activity. Results: No difference in cIMT between HP and LP group was observed. Insulin, HOMA-IR index and total IGF-1 were positively associated with cIMT but after adjustment for confounders only an inverse association between ApoA1 and positive between ApoB/ApoA1 and cIMT were significant. Conclusion: High versus low protein intake in infancy does not influence cIMT at 5 years. cIMT in healthy children at 5 years is associated with their apolipoprotein profile.
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- 2014
34. Upregulation of Vascular NAD(P)H Oxidase Subunit gp91phox and Impairment of the Nitric Oxide Signal Transduction Pathway in Hypertension
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Henning Morawietz, Georg Kojda, Andreas Hacker, Martina Weber, Uwe Rueckschloss, and Nadine Lauer
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Male ,medicine.medical_specialty ,GUCY1B3 ,Vasodilator Agents ,Blotting, Western ,Biophysics ,Aorta, Thoracic ,In Vitro Techniques ,Nitric Oxide ,Biochemistry ,Nitric oxide ,chemistry.chemical_compound ,Downregulation and upregulation ,Superoxides ,Rats, Inbred SHR ,Internal medicine ,medicine ,Animals ,NADH, NADPH Oxidoreductases ,Nitric Oxide Donors ,RNA, Messenger ,Rats, Wistar ,Lung ,Molecular Biology ,Oxidase test ,Membrane Glycoproteins ,NADPH oxidase ,biology ,Chemistry ,NADPH Oxidases ,Cell Biology ,Rats ,Up-Regulation ,Enzyme Activation ,Vasodilation ,Protein Subunits ,Endocrinology ,Guanylate Cyclase ,NAD(P)H oxidase ,Hypertension ,NADPH Oxidase 2 ,cardiovascular system ,biology.protein ,NAD+ kinase ,Signal transduction ,Signal Transduction - Abstract
In this study we analyzed the role of vascular NAD(P)H oxidase in the generation of O−2 and the endothelial impairment of NO signal transduction pathway in hypertension. In aortic rings of 15-month-old stroke-prone spontaneously hypertensive rats (SHR15) we found a 10-fold increased expression of NAD(P)H oxidase subunit gp91phox mRNA associated with a 3-fold increased production of O−2 comparedto age-matched Wistar rats (WIS15). Vasorelaxationstudies in aortas of SHR15 showed a strongly diminished response to acetylcholine, NO-donor S-nitroso-N-acetyl- d,l -penicillamine, and organic nitrate glyceryl trinitrate compared to WIS15. Soluble guanylate cyclase (sGC) activity and sGC β1-subunit protein expression was downregulated in aortas and lungs of SHR15. These data suggest an upregulation of vascular NAD(P)H oxidase and an impairment of the NO signal transduction pathway in hypertension.
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- 2001
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35. Palynology of the perigoniate Aroideae: Zamioculcas, Gonatopus and Stylochaeton (Araceae)
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Michael Hesse, Josef Bogner, Martina Weber, and Heidemarie Halbritter
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Palynology ,Monstera ,biology ,Gonatopus ,Plant Science ,Zamioculcas ,biology.organism_classification ,medicine.disease_cause ,Araceae ,Pollen ,Botany ,Amydrium ,medicine ,Ecology, Evolution, Behavior and Systematics ,Aroideae - Abstract
The pollen of the perigoniate Aroideae sensu Mayo et al. (1997) ( Zamioculcas Schott, Gonatopus Hook. f. ex Engl. and Stylochaeton Lepr.) differs ultrastructurally from that of the aperigoniate Aroideae in several important exine and aperture characters. The almost identical zona-aperturate pollen of Zamioculcas and Gonatopus has outside the aperture an elaborated, thick ectexine, while the aperture consists of a thin, but continuous ectexine and a thick, lamellate endexine. In contrast, the omniaperturate pollen of Stylochaeton has a thin, not clearly stratified ectexine and a thin, heterogeneous endexine below. However, the zona-aperturate pollen of Zamioculcas and Gonatopus deviates significantly from the superficially similar zona-aperturate pollen of the unrelated Monstereae (e. g., Monstera Adans., Amydrium Schott): in the apertures of Monstera or Amydrium both the thin, but continuous ectexine and the lamellate endexine, which are typical features for Zamioculcas and Gonatopus , are absent. The pal...
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- 2001
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36. Eosinophils Maintain Their Capacity to Signal and Release Eosinophil Cationic Protein Upon Repetitive Stimulation with the Same Agonist
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Martina Weber, Francesca Levi-Schaffer, Kurt Blaser, Yael Zilberman, Eva Becker, and Hans-Uwe Simon
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Chemokine CCL11 ,Eotaxin ,Agonist ,Time Factors ,medicine.drug_class ,education ,Immunology ,Complement C5a ,Receptors, Cell Surface ,Stimulation ,Platelet Membrane Glycoproteins ,Receptors, G-Protein-Coupled ,Cytosol ,Ribonucleases ,fluids and secretions ,Eosinophilia ,medicine ,Humans ,Immunology and Allergy ,Eosinophil degranulation ,Platelet Activating Factor ,Receptor ,Cells, Cultured ,Eosinophil cationic protein ,biology ,Cell Membrane ,Granulocyte-Macrophage Colony-Stimulating Factor ,Blood Proteins ,Eosinophil Granule Proteins ,respiratory system ,Eosinophil ,Eosinophils ,medicine.anatomical_structure ,Gene Expression Regulation ,Desensitization, Immunologic ,Organ Specificity ,Chemokines, CC ,Major basic protein ,biology.protein ,Cytokines ,Calcium ,Signal Transduction - Abstract
Eosinophils contain in their granules eosinophil cationic protein (ECP) and other basic proteins that have been implicated in immunity to parasites and pathophysiology of chronic allergic responses. In a model of eosinophil degranulation, we show that eosinophils release ECP upon short-term GM-CSF priming and stimulation with either platelet-activating factor (PAF) or the anaphylatoxin C5a, but not eotaxin. Restimulation with the same agonist (PAF or C5a) was unsuccessful as assessed by monitoring intracellular calcium concentration and ECP release. In contrast, upon an intermediate washing step, eosinophils rapidly transduced PAF and C5a signals followed by significant ECP releases. Ligand-binding studies demonstrated that only a proportion of PAF receptors is internalized upon cell stimulation and that washing of the cells removes the agonist from the cell surface. Upon repetitive stimulation, eosinophils with less than 50% of the original ECP content were obtained. Such eosinophils did not increase cellular ECP levels even in the presence of the eosinophil survival factor GM-CSF in overnight cultures. In vivo studies revealed that eosinophils always express detectable amounts of ECP under chronic inflammatory conditions. In conclusion, we have shown that eosinophils maintain their capacity to degranulate upon repetitive stimulation with the same agonist as long as the receptor is not occupied from a previous stimulation. The cellular content of ECP appears to be a no limiting factor in the case of repetitive stimulation, implying that mature eosinophils may not require a significant ECP resynthesis.
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- 2000
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37. Pollen walls of Araceae, with special reference to their fossilization potential
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Heidemarie Halbritter, Michael Hesse, and Martina Weber
- Subjects
Fossil Record ,Pollen ,Botany ,medicine ,Ultrastructure ,Plant Science ,Biology ,medicine.disease_cause ,biology.organism_classification ,Fossilization ,Ecology, Evolution, Behavior and Systematics ,Araceae - Abstract
Araceae, a basal monocot family, has a very poor fossil record, especially with regard to pollen grains. An ultrastructural study of Araceae pollen walls was undertaken to answer the questions: which pollen is resistant to decay and will appear in the fossil record? and which pollen has a smaller fossilization potential and why? The wall strata of Araceae pollen differ in morphology and chemical composition. Only a minority of all Araceae pollen grains has the ?conventional? type of exine architecture consisting of an acetolysis-resistant ektexine upon a generally thin, but ratherspongy endexine. Pollen grains with this type of exine have a high fossilization potential and should be found unmodified in the fossil record. In contrast, the majority of Araceae pollen has a strikingly different, newly discovered exine architecture: a thick, spongy, acetolysis-resistant endexine is covered by an outer stratum, which either may or may not be resistant to acetolysis. We conclude from these features that the pote...
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- 1999
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38. The Basic Pollen Wall Types in Araceae
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Michael Hesse, Martina Weber, and Heidemarie Halbritter
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biology ,Spathiphyllum ,Botany ,Ultrastructure ,Pistia ,Plant Science ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics ,Araceae ,Arum ,Pollen wall ,Zantedeschia ,Staining - Abstract
An ultrastructural investigation of 60 species, representing 47 genera, of Araceae showed two basic pollen wall types, each with two subtypes. The two main types are distinguished by presence (type 1) or absence (type 2) of an acetolysis‐resistant ektexine. The subtypes are differentiated by a structured (type 1a) or unstructured (type 1b) ektexine, respectively, and the presence (type 2a) or absence (type 2b) of polysaccharidic wall ornamentations. A characteristic of all types is a spongy endexine, which is electron dense after thiocarbohydrazide–silver proteinate staining and is only partially resistant to acetolysis.
- Published
- 1999
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39. The Spiny Pollen Wall in Sauromatum (Araceae)-with Special Reference to the Endexine
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Heidemarie Halbritter, Martina Weber, and Michael Hesse
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Tapetum ,biology ,Stamen ,food and beverages ,Plant Science ,Anatomy ,biology.organism_classification ,medicine.disease_cause ,Araceae ,Sauromatum ,Pollen ,Botany ,otorhinolaryngologic diseases ,medicine ,Ecology, Evolution, Behavior and Systematics ,Pollen wall - Abstract
Pollen grains of Sauromatum are inaperturate with a microechinate exine ornamentation. The outer pollen wall is formed by the spongious endexine and spines. An acetolysis-resistant ektexine is missing. The endexine appears electron dense after TCH-Sp staining and electron translucent after the Thiery-test. The spines are polysaccharidic in nature. Acetolysis leads to a considerable increase in pollen size and destroys the spines. PAS-positive Ubisch body-like structures are found within the anther loculus. The tapetum is of the amoeboid type. Spines as well as Ubisch bodylike structures are formed by the tapetum at the stage of first pollen mitosis.
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- 1998
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40. MiRNA-155 targets myosin light chain kinase and modulates actin cytoskeleton organization in endothelial cells
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Nicole Patterson, Charles D. Searles, Martina Weber, Sinae Kim, and Kimberly Rooney
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Male ,Myosin light-chain kinase ,RHOA ,Cytoskeleton organization ,Physiology ,Fluorescent Antibody Technique ,Transfection ,Actin cytoskeleton organization ,Mice ,Physiology (medical) ,Human Umbilical Vein Endothelial Cells ,Animals ,Humans ,Cytoskeleton ,Myosin-Light-Chain Kinase ,Aorta ,biology ,Endothelial Cells ,MYLK ,Actin cytoskeleton ,Atherosclerosis ,Molecular biology ,Cell biology ,Endothelial stem cell ,Mice, Inbred C57BL ,Actin Cytoskeleton ,MicroRNAs ,Phenotype ,biology.protein ,Signaling and Stress Response ,Cardiology and Cardiovascular Medicine ,rhoA GTP-Binding Protein - Abstract
Previously, we identified a microRNA (miRNA) signature for endothelial cells (ECs) subjected to unidirectional shear stress (USS). MiR-155, a multifunctional miRNA that has been implicated in atherosclerosis, was among the shear stress-responsive miRNAs. Here, we examined the role of miR-155 in modulating EC phenotype and function. In vitro, increased miR-155 levels in human ECs induced changes in morphology and filamentous (F)-actin organization. In addition, ECs transfected with miR-155 mimic were less migratory and less proliferative and had less apoptosis compared with control ECs. In mouse aorta, miR-155 expression was increased in the intima of thoracic aorta, where blood flow produces steady and unidirectional shear stress, compared with the intima of the lower curvature of the aortic arch, which is associated with oscillatory and low shear stress. These differences in miR-155 expression were associated with distinct changes in EC morphology and F-actin. The effects of miR-155 in vitro were mediated through suppression of two key regulators of the EC cytoskeleton organization: RhoA and myosin light chain kinase (MYLK). A novel direct interaction between miR-155 and the MYLK 3′UTR was verified by luciferase-MYLK 3′UTR reporter assays. Furthermore, the intensity of immunofluorescence staining for RhoA and MYLK in mouse aorta correlated inversely with miR-155 expression. In conclusion, a prominent effect of the multifunctional miR-155 in ECs is modulation of phenotype through alterations in RhoA, MYLK expression, and actin cytoskeleton organization.
- Published
- 2014
41. Calla palustris (Araceae): New palynological insights with special regard to its controversial systematic position and to closely related genera
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Heidemarie Halbritter, Martina Weber, Josef Bogner, Michael Hesse, David Bröderbauer, and Silvia Ulrich
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Subfamily ,biology ,Calla ,Calloideae ,Plant Science ,medicine.disease_cause ,biology.organism_classification ,Article ,Pollen ,Botany ,medicine ,Ecology, Evolution, Behavior and Systematics ,Pollen wall ,Lasioideae ,Aperture (botany) ,Aroideae - Abstract
Almost all systematic treatments agree that Calla is a puzzling case, being a highly autapomorphic taxon with obscure relationships. In molecular-based classifications the variable placements of Calla within Aroideae conflict strongly with those in morphologically and anatomically based systematic classifications, which treat the genus as a subfamily (Calloideae) of its own. We studied the pollen morphology and ultrastructure of Calla by light and electron microscopy, and mapped the relevant pollen characters as well as some flower characters to the proposed placements of Calla within the Araceae as indicated in the various molecular phylogenies. Calla pollen is extraordinary within the entire Araceae. Pollen grains are small, and basically disulcate or with a ring-like aperture. The ornamentation is psilate to perforate, and the pollen wall consists of a sporopolleninous tectate-columellate exine. These pollen characters are shared with those of several earlier-diverging aroid taxa, especially with those of subfamily Zamioculcadoideae, whereas pollen characters in members of subfamily Aroideae deviate significantly. These findings are in accordance with other floral characters. Therefore, we propose that Calla is best placed in a transition zone between either subfamily Zamioculcadoideae (Stylochaeton clade) and subfamily Aroideae (Aroideae clade) or between subfamily Zamioculcadoideae (Stylochaeton clade) and subfamily Lasioideae.
- Published
- 2013
42. Apertural chambers inGeranium: Development and ultrastructure
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Martina Weber
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biology ,food and beverages ,Cell Biology ,Plant Science ,medicine.disease_cause ,biology.organism_classification ,law.invention ,Geranium pratense ,Tricolpate ,Microspore ,law ,Pollen ,Botany ,otorhinolaryngologic diseases ,medicine ,Ultrastructure ,Pollen tube ,Electron microscope ,Aperture (botany) - Abstract
Pollen grains ofGeranium robertianum andG. pratense are tricolpate. At the time of the vacuolated microspore stage intine protrusions are formed at each aperture. Each aperture becomes separated from the vegetative cytoplasm by a thick ectintine layer. Starch grains are enclosed in the protrusions and do not participate in pollen tube growth.
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- 1996
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43. The Existence of a Special Exine Coating in Geranium robertianum Pollen
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Martina Weber
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biology ,Vesicle ,Endoplasmic reticulum ,Plant Science ,medicine.disease_cause ,biology.organism_classification ,Pollen ,Botany ,medicine ,Geranium robertianum ,Geraniaceae ,Ecology, Evolution, Behavior and Systematics ,Pollen maturation ,Pollen wall - Abstract
The outer pollen wall of Geranium robertianum L. (Geraniaceae) is exclusively formed by the ectexine, characterized by a perforated footlayer, unbranched columellae, a tectum that forms a reticulum, and supratectate pila. An endexine is missing. The intine protrudes through the channels of the footlayer to the exine cavities. The intine material in the exinic interstices is immediately covered by tapetally synthesized vesicles, called pollen-coating vesicles (PCV), which form a compact layer within the exine cavities. The PCV layer is interpreted as a protecting barrier. During final pollen maturation the PCV layer is superimposed with lipidic pollenkitt. Endoplasmic reticulum and elaioplasts participate in the pollenkitt formation. The electron-translucent zones at the bottom of the exine cavities may represent degeneration products of the primexine matrix.
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- 1996
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44. The Development of the Transmitting Tract in the Pistil of Hacquetia epipactis (Apiaceae)
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Andrea Frosch and Martina Weber
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Gynoecium ,Apiaceae ,biology ,Plant Science ,Hacquetia epipactis ,biology.organism_classification ,medicine.disease_cause ,Surface coating ,Germination ,Pollen ,Botany ,Ultrastructure ,medicine ,Pollen tube ,Ecology, Evolution, Behavior and Systematics - Abstract
Hacquetia epipactis has a wet, nonpapillate stigma. Stigmatic cells are moribund at maturity and become disrupted because of accumulated and ascending stylar secretion. The stigmatic surface coating is produced completely by the stylar transmitting tissue. The style is a half-solid type, with large secretion-filled schizogenous channels. The secretion mainly contains polysaccharides mixed with a small amount of lipids. Pollen grains germinate within the stigmatic secretion and the pollen tubes grow directly into the stylar channels.
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- 1995
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45. miR181a protects against angiotensin II-induced osteopontin expression in vascular smooth muscle cells
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Natalia Landázuri, Daiana Weiss, Martina Weber, Alicia N. Lyle, W. Robert Taylor, Charles D. Searles, and Ebony Washington Remus
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medicine.medical_specialty ,Vascular smooth muscle ,Transcription, Genetic ,Gene Expression ,Biology ,Muscle, Smooth, Vascular ,Article ,stomatognathic system ,Transcription (biology) ,Internal medicine ,Gene expression ,microRNA ,medicine ,Animals ,Vasoconstrictor Agents ,Osteopontin ,RNA, Messenger ,Aorta ,Cells, Cultured ,Angiotensin II ,RNA ,Adhesion ,Cell biology ,Rats ,MicroRNAs ,Endocrinology ,cardiovascular system ,biology.protein ,Cardiology and Cardiovascular Medicine - Abstract
Osteopontin (OPN) is a multifunctional protein found in abundance in atherosclerotic plaques. Angiotensin II (Ang II) promotes atherosclerosis by inducing adhesion and migration of vascular smooth muscle cells (VSMCs). MicroRNAs (miRNAs) are critical regulators of protein expression. However, the relationship between Ang II, miRNAs and OPN has yet to be fully explored.Using cultured VSMCs, we found that Ang II increased cellular OPN protein expression 4 h after treatment by 420 ± 54% (p0.03) in a translation dependent manner. Sequence analysis revealed a putative binding site for mir181a and raised the possibility that miR181a is a potential regulatory mechanism for OPN expression. We demonstrated that Ang II decreased miR181a expression by 52 ± 7% (p0 .0001) and overexpressing miR181a inhibited Ang II induced increases in OPN protein expression by 69 ± 9% (p0.05). Furthermore, we demonstrated that miR181a is functionally important in that overexpression of miR181a inhibited VSMCs adhesion to collagen in response to Ang II as compared to controls by 36 ± 4%. (p0.05) CONCLUSIONS: These results demonstrate that miR181a regulates OPN expression and that altering miR181a expression may be a novel therapeutic approach to modulate OPN protein expression.
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- 2012
46. Overexpression of mir181a protects against Ang II induced osteopontin expression in VSMC
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Martina Weber, Alicia N. Lyle, Robert W. Taylor, Charles D. Searles, and Ebony Washington Remus
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biology ,Chemistry ,Genetics ,biology.protein ,Osteopontin ,Molecular Biology ,Biochemistry ,Biotechnology ,Cell biology - Published
- 2012
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47. Hepatic induction of cholesterol biosynthesis reflects a remote adaptive response to pneumococcal pneumonia
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Michael Kiehntopf, James C. Paton, Michael Bauer, Ulrich A. Maus, Nadine Ding, Martina Weber, Ralf A. Claus, David Enot, Abiodun D. Ogunniyi, Emeka I. Igwe, Debra Weih, Yoram Vodovotz, Hans P. Deigner, Sandro Lambeck, Lucien Frappart, David E. Briles, Matthias Kohl, Stefanie Henken, Thomas Kamradt, Weber, Martina, Lambeck, Sandro, Ding, Nadine, Henken, Stefanie, Kohl, Matthias, Deigner, Hans P, Enot, David P, Igwe, Emeka I, Frappart, Lucien, Kiehntopf, Michael, Claus, Ralf A, Kamradt, Thomas, Weih, Debra, Vodovotz, Yoram, Briles, David E, Ogunniyi, Abiodun D, Paton, James C, Maus, Ulrich A, and Bauer, Michael
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Life Sciences & Biomedicine - Other Topics ,Biochemistry & Molecular Biology ,Protein Array Analysis ,Medizin ,Biology ,medicine.disease_cause ,Biochemistry ,Microbiology ,Sepsis ,sepsis ,Mice ,Bacterial Proteins ,Streptococcus pneumoniae ,Macrophages, Alveolar ,Genetics ,medicine ,Animals ,Molecular Biology ,Pneumolysin ,Septic shock ,Cell Biology ,pneumolysin ,respiratory system ,Pneumonia, Pneumococcal ,medicine.disease ,Mice, Inbred C57BL ,Pneumonia ,Cholesterol ,Liver ,Pneumococcal pneumonia ,Immunology ,Lobar pneumonia ,Streptolysins ,Alveolar macrophage ,pathogen-host interaction ,Female ,Biotechnology - Abstract
Community-acquired pneumonia presents a spectrum of clinical phenotypes, from lobar pneumonia to septic shock, while mechanisms underlying progression are incompletely understood. In a transcriptomic and metabolomic study across tissues, we examined serotype-specific regulation of signaling and metabolic pathways in C57BL/6 mice intratracheally instilled with either serotype 19F Streptococcus pneumoniae (S19; causing lobar pneumonia), or serotype 2 S. pneumoniae (S2; causing septic pneumococcal disease,) or vehicle (Todd-Hewitt broth). Samples of lung, liver, and blood were collected at 6 and 24 h postinfection and subjected to microarray analysis and mass spectrometry. Results comprise a preferential induction of cholesterol biosynthesis in lobar pneumonia at low-infection doses (105 colony forming units/mouse) leading to increased plasma cholesterol (vehicle: 1.8 +/- 0.12 mM, S2: 2.3 +/- 0.10 mM, S19: 2.9 +/- 0.15 mM; P
- Published
- 2012
48. 'Pollen Buds' in Ophiorrhiza (Rubiaceae) and their Role in Pollenkitt Release
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A. Igersheim and Martina Weber
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Tapetum ,Rubiaceae ,biology ,Pollen ,Botany ,otorhinolaryngologic diseases ,medicine ,food and beverages ,Plant Science ,Immunogold labelling ,biology.organism_classification ,medicine.disease_cause ,Ophiorrhiza - Abstract
Pollen buds are apertural protrusions formed by the ectintine. In their wall unesterified and methyl-esterified pectins are detected by immunogold labeling. During pollenkitt formation pollen buds become adpressed and connected to the tapetum wall. The following expansion of the endothecium causes the mechanical rupture of the tapetum at the binding sites of the pollen buds. These events are accompanied by the release of the pollenkitt.
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- 1994
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49. Stigma, Style, and Pollen Tube Pathway in Smyrnium perfoliatum (Apiaceae)
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Martina Weber
- Subjects
Surface coating ,Apiaceae ,biology ,Botany ,Extracellular ,Secretion ,Pollen tube ,Plant Science ,Smyrnium perfoliatum ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics - Abstract
Smyrnium perfoliatum has a solid style and a wet, nonpapillate stigma. The stigmatic surface coating is totally produced by the stylar transmitting tissue. The main secretion compounds are unsaturated lipids and methylesterified pectins. Lipid transport from the cells of the transmitting tissue to the extracellular space occurs by multivesicular bodies. The accumulating secretion forms an axial array of intercellular channels within the transmitting tissue. Ascending secretion forces the stigma cells to separate from each other. Pollen tubes enter the style between the stigmatic cells and grow within the secretion-filled channel.
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- 1994
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50. Sex differences in the endocrine system in response to protein intake early in life
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Ricardo, Closa-Monasterolo, Natàlia, Ferré, Verónica, Luque, Marta, Zaragoza-Jordana, Veit, Grote, Martina, Weber, Berthold, Koletzko, Piotr, Socha, Dariusz, Gruszfeld, Roman, Janas, Annick, Xhonneux, Elena, Dain, Silvia, Scaglioni, Joaquin, Escribano, and Fiammetta, Vecchi
- Subjects
Leptin ,Male ,medicine.medical_specialty ,Medicine (miscellaneous) ,Nutritional Status ,High-protein diet ,Endocrine System ,Biology ,medicine.disease_cause ,Body Mass Index ,chemistry.chemical_compound ,Child Development ,Sex Factors ,Double-Blind Method ,Internal medicine ,medicine ,Endocrine system ,Humans ,Insulin-Like Growth Factor I ,Infant Nutritional Physiological Phenomena ,Creatinine ,Nutrition and Dietetics ,C-peptide ,Body Weight ,Infant ,Body Height ,Infant Formula ,Insulin-Like Growth Factor Binding Protein 2 ,Endocrinology ,chemistry ,Female ,Dietary Proteins ,Body mass index ,Sex characteristics ,Hormone - Abstract
Background: Nutritional factors during a sensitive period can influence child development in a sex-related manner. Objective: Our aim was to investigate whether sex modulates the responses of relevant biochemical parameters and growth to different protein intakes early in life. Design: In a randomized controlled trial, formula-fed infants were assigned to receive formula with higher protein (HP) or lower protein (LP) content. The main outcome measures were insulin-like growth factor (IGF)-1 axis parameters, weight, length, BMI, leptin, and C-peptide/creatinine ratio at 6 mo of age. Dietary intake during the first 6 mo of life was also assessed. Results: The IGF-1 axis response to HP feeding was modulated by sex. Total and free IGF-1 and IGF binding protein 3 concentrations were higher in girls than in boys. Compared with the LP diet, the HP diet was associated with higher IGF-1 and lower IGF binding protein 2 secretion. The response to this HP content formula tended to be stronger in girls than in boys. The HP diet was associated with a higher C-peptide/creatinine ratio. The leptin concentration was higher in girls than in boys and was correlated to the IGF-1 axis parameters. No interaction between sex and nutritional intervention was shown on growth. Conclusions: Our findings show that the endocrine response to a high protein diet early in life may be modulated by sex. The IGF-1 axis of female infants shows a stronger response to the nutritional intervention than does that of male infants, but there is no enhanced effect on growth. This trial was registered at clinicaltrials. gov as NCT00338689. © 2011 American Society for Nutrition.
- Published
- 2011
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