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151.
S. Thomar Ulrike Dumke-Lehmann Beate Diettrich M. Luckner 《Plant biology (Stuttgart, Germany)》1998,111(1):22-27
Digitalis lanata was transformed by agrobacteria-mediated gene transfer with a chimeric reporter gene encoding for β-glucuronidase (CUS) from Escherichia coll under the control of the plastocyanin 3 (Pc3) promoter from Spinada oleracea (Pc3::uidA fusion gene). Transformed cell lines were regenerated to plants via somatic embryos. CUS activity was determined fluorometrically and histochemically. The Pc3::uidA fusion gene was expressed in the late globular and bipolar stages of somatic embryos. Expression started in globular embryos (stage-1-globules) in that part of the parenchymatic tissue which later on formed the cotyledons. No GUS activity was detectable in the parenchymatic tissue forming the root pole, in cells of the developing procambium or in epidermal cells. These tissues were free of GUS activity also in bipolar embryos. The parenchymatic cells of the cotyledons and the primary cortex of the hypocotyl of germinating embryos showed GUS activity, in contrast to the epidermal cells and the cells of the central cylinder. 相似文献
152.
Ekkehard Schönbohm Ute Babbel Ulrike Czeska-Werner Sebastian Zellner Hans-Georg Zwicker 《Physiologia plantarum》1994,91(2):285-289
Our question is whether the stimulating effect of a cold dark-pretreatment on the process of de-etiolation in primary leaves of wheat seedlings under subsequent continuous white light is essentially mediated by the retarding effect of highly lowered temperatures on the following processes: aging and/or senescence, realization of the so-called excision factor in detached leaves, decrease of the cytokinin level in detached leaves. The strong stimulating effect of a cold dark-preatreatment remains inspite of progressive aging in parts of the leaves and a strong decrease of the capability of chlorophyll accumulation in detached in contrast to attached leaves. The strong stimulatory effect of a cold dark-pretreatment is not diminished by application of cytokinin or gibberellic acid. The stimulating effect of a cold dark-pretreatment is detectable over several days under continuous light, but it is lost during a warm dark-phase of a few hours duration between the cold dark-pretreatment and the white light phase. 相似文献
153.
René H?hn Ulrike Kottler Tunde Peto Maria Blettner Thomas Münzel Stefan Blankenberg Karl J. Lackner Manfred Beutel Philipp S. Wild Norbert Pfeiffer 《PloS one》2015,10(3)
Purpose
This paper describes the study design, methodology, cohort profile and self-reported diseases in the ophthalmological branch of the Gutenberg Health Study (GHS).Methods
The GHS is an ongoing, prospective, interdisciplinary, single-center, population-based cohort study in Germany. The main goals of the ophthalmological section are to assess the prevalence and incidence of ocular diseases and to explore risk factors, genetic determinants and associations with systemic diseases and conditions. The eye examination at baseline included a medical history, self-reported eye diseases, visual acuity, refractive errors, intraocular pressure, visual field, pachymetry, keratometry, fundus photography and tear sampling. The 5-year follow-up visit additionally encompassed optical coherence tomography, anterior segment imaging and optical biometry. The general examination included anthropometry; blood pressure measurement; carotid artery ultrasound; electrocardiogram; echocardiography; spirometry; cognitive tests; questionnaires; assessment of mental conditions; and DNA, RNA, blood and urine sampling.Results
Of 15,010 participants (aged 35-74 years at the time of inclusion), ocular data are available for 14,700 subjects (97.9%). The mean visual acuity (standard deviation), mean spherical equivalent, median decimal visual acuity, and mean intraocular pressure were 0.08 (0.17) logMar, -0.42 (2.43) diopters, 0.9 and 14.24 (2.79) mm Hg, respectively. The frequencies of self-reported strabismus, glaucoma, surgery for retinal detachment and retinal vascular occlusions were 2.7%, 2.3%, 0.2% and 0.4%, respectively.Conclusions
The GHS is the most extensive dataset of ophthalmic diseases and conditions and their risk factors in Germany and one of the largest cohorts worldwide. This dataset will provide new insight in the epidemiology of ophthalmic diseases and related medical specialties. 相似文献154.
Jochen W?hrle Mahir Karakas Ulrike Trepte Julia Seeger Birgid Gonska Wolfgang Koenig Wolfgang Rottbauer 《PloS one》2015,10(9)
Background
It is not known whether biomarkers of hemodynamic stress, myocardial necrosis, and renal function might predict adverse outcome in patients undergoing percutaneous repair of severe mitral valve insufficiency. Thus, we aimed to assess the predictive value of various established and emerging biomarkers for major adverse cardiovascular events (MACE) in these patients.Methods
Thirty-four patients with symptomatic severe mitral valve insufficiency with a mean STS-Score for mortality of 12.6% and a mean logistic EuroSCORE of 19.7% undergoing MitraClip therapy were prospectively included in this study. Plasma concentrations of mid regional-proatrial natriuretic peptide (MR-proANP), Cystatin C, high-sensitive C-reactive protein (hsCRP), high-sensitive troponin T (hsTnT), N-terminal B-type natriuretic peptide (NT-proBNP), galectin-3, and soluble ST-2 (interleukin 1 receptor-like 1) were measured directly before procedure. MACE was defined as cardiovascular death and hospitalization for heart failure (HF).Results
During a median follow-up of 211 days (interquartile range 133 to 333 days), 9 patients (26.5%) experienced MACE (death: 7 patients, rehospitalization for HF: 2 patients). Thirty day MACE-rate was 5.9% (death: 2 patients, no rehospitalization for HF). Baseline concentrations of hsTnT (Median 92.6 vs 25.2 ng/L), NT-proBNP (Median 11251 vs 1974 pg/mL) and MR-proANP (Median 755.6 vs 318.3 pmol/L, all p<0.001) were clearly higher in those experiencing an event vs event-free patients, while other clinical variables including STS-Score and logistic EuroSCORE did not differ significantly. In Kaplan-Meier analyses, NT-proBNP and in particular hsTnT and MR-proANP above the median discriminated between those experiencing an event vs event-free patients. This was further corroborated by C-statistics where areas under the ROC curve for prediction of MACE using the respective median values were 0.960 for MR-proANP, 0.907 for NT-proBNP, and 0.822 for hsTnT.Conclusions
MR-proANP and hsTnT strongly predict cardiovascular death and rehospitalization for HF in patients undergoing percutaneous repair of mitral valve insufficiency. Both markers might be useful components in new scoring systems to better predict short- and potentially long-term mortality and morbidity after MitraClip procedure. 相似文献155.
156.
157.
Bert-Ewald Priegnitz Ulrike Brandt Khomaizon A. K. Pahirulzaman Jeroen S. Dickschat André Flei?ner 《Eukaryotic cell》2015,14(6):602-615
Adaptation to a changing environment is essential for the survival and propagation of sessile organisms, such as plants or fungi. Filamentous fungi commonly respond to a worsening of their growth conditions by differentiation of asexually or sexually produced spores. The formation of these specialized cell types is, however, also triggered as part of the general life cycle by hyphal age or density. Spores typically serve for dispersal and, therefore, translocation but can also act as resting states to endure times of scarcity. Eukaryotic differentiation in response to environmental and self-derived signals is commonly mediated by three-tiered mitogen-activated protein (MAP) kinase signaling cascades. Here, we report that the MAP kinase Fus3 of the black mold Aspergillus niger (AngFus3) and its upstream kinase AngSte7 control vegetative spore formation and secondary metabolism. Mutants lacking these kinases are defective in conidium induction in response to hyphal density but are fully competent in starvation-induced sporulation, indicating that conidiation in A. niger is triggered by various independent signals. In addition, the mutants exhibit an altered profile of volatile metabolites and secrete dark pigments into the growth medium, suggesting a dysregulation of the secondary metabolism. By assigning the AngFus3 MAP kinase pathway to the transduction of a potentially self-derived trigger, this work contributes to the unraveling of the intricate signaling networks controlling fungal differentiation. Moreover, our data further support earlier observations that differentiation and secondary metabolism are tightly linked in filamentous fungi. 相似文献
158.
Ulrike Pichler Michael Hauser Martin Wolf Maria Livia Bernardi Gabriele Gadermaier Richard Weiss Christof Ebner Hidenori Yokoi Toshiro Takai Alain Didierlaurent Chiara Rafaiani Peter Briza Adriano Mari Heidrun Behrendt Michael Wallner Fátima Ferreira 《PloS one》2015,10(5)
BackgroundPollen released by allergenic members of the botanically unrelated families of Asteraceae and Cupressaceae represent potent elicitors of respiratory allergies in regions where these plants are present. As main allergen sources the Asteraceae species ragweed and mugwort, as well as the Cupressaceae species, cypress, mountain cedar, and Japanese cedar have been identified. The major allergens of all species belong to the pectate lyase enzyme family. Thus, we thought to investigate cross-reactivity pattern as well as sensitization capacities of pectate lyase pollen allergens in cohorts from distinct geographic regions.MethodsThe clinically relevant pectate lyase pollen allergens Amb a 1, Art v 6, Cup a 1, Jun a 1, and Cry j 1 were purified from aqueous pollen extracts, and patients´ sensitization pattern of cohorts from Austria, Canada, Italy, and Japan were determined by IgE ELISA and cross-inhibition experiments. Moreover, we performed microarray experiments and established a mouse model of sensitization.ResultsIn ELISA and ELISA inhibition experiments specific sensitization pattern were discovered for each geographic region, which reflected the natural allergen exposure of the patients. We found significant cross-reactivity within Asteraceae and Cupressaceae pectate lyase pollen allergens, which was however limited between the orders. Animal experiments showed that immunization with Asteraceae allergens mainly induced antibodies reactive within the order, the same was observed for the Cupressaceae allergens. Cross-reactivity between orders was minimal. Moreover, Amb a 1, Art v 6, and Cry j 1 showed in general higher immunogenicity.ConclusionWe could cluster pectate lyase allergens in four categories, Amb a 1, Art v 6, Cup a 1/Jun a 1, and Cry j 1, respectively, at which each category has the potential to sensitize predisposed individuals. The sensitization pattern of different cohorts correlated with pollen exposure, which should be considered for future allergy diagnosis and therapy. 相似文献
159.
While several phylogenetically diverse species have proved capable of learning abstract concepts, previous attempts to teach fish have been unsuccessful. In this report, the ability of archerfish (Toxotes chatareus) to learn the concepts of sameness and difference using a simultaneous two-item discrimination task was tested. Six archerfish were trained to either select a pair of same or different stimuli which were presented simultaneously. Training consisted of a 2-phase approach. Training phase 1: the symbols in the same and different pair did not change, thereby allowing the fish to solve the test through direct association. The fish were trained consecutively with four different sets of stimuli to familiarize them with the general procedure before moving on to the next training phase. Training phase 2: six different symbols were used to form the same or different pairs. After acquisition, same/different concept learning was tested by presenting fish with six novel stimuli (transfer test). Five fish successfully completed the first training phase. Only one individual passed the second training phase, however, transfer performance was consistent with chance. This individual was given further training using 60 training exemplars but the individual was unable to reach the training criterion. We hypothesize that archerfish are able to solve a limited version of the same/different test by learning the response to each possible stimulus configuration or by developing a series of relatively simple choice contingencies. We conclude that the simultaneous two-item discrimination task we describe cannot be successfully used to test the concepts of same and different in archerfish. In addition, despite considerable effort training archerfish using several tests and training methods, there is still no evidence that fish can learn an abstract concept-based test. 相似文献
160.
Aleksandra Inic-Kanada Marijana Stojanovic Simone Schlacher Elisabeth Stein Sandra Belij-Rammerstorfer Emilija Marinkovic Ivana Lukic Jacqueline Montanaro Nadine Schuerer Nora Bintner Vesna Kovacevic-Jovanovic Ognjen Krnjaja Ulrike Beate Mayr Werner Lubitz Talin Barisani-Asenbauer 《PloS one》2015,10(12)
Trachoma, caused by the intracellular bacterium Chlamydia trachomatis (Ct), remains the world’s leading preventable infectious cause of blindness. Recent attempts to develop effective vaccines rely on modified chlamydial antigen delivery platforms. As the mechanisms engaged in the pathology of the disease are not fully understood, designing a subunit vaccine specific to chlamydial antigens could improve safety for human use. We propose the delivery of chlamydia-specific antigens to the ocular mucosa using particulate carriers, bacterial ghosts (BGs). We therefore characterized humoral and cellular immune responses after conjunctival and subcutaneous immunization with a N-terminal portion (amino acid 1–893) of the chlamydial polymorphic membrane protein C (PmpC) of Ct serovar B, expressed in probiotic Escherichia coli Nissle 1917 bacterial ghosts (EcN BGs) in BALB/c mice. Three immunizations were performed at two-week intervals, and the immune responses were evaluated two weeks after the final immunization in mice. In a guinea pig model of ocular infection animals were immunized in the same manner as the mice, and protection against challenge was assessed two weeks after the last immunization. N-PmpC was successfully expressed within BGs and delivery to the ocular mucosa was well tolerated without signs of inflammation. N-PmpC-specific mucosal IgA levels in tears yielded significantly increased levels in the group immunized via the conjunctiva compared with the subcutaneously immunized mice. Immunization with N-PmpC EcN BGs via both immunization routes prompted the establishment of an N-PmpC-specific IFNγ immune response. Immunization via the conjunctiva resulted in a decrease in intensity of the transitional inflammatory reaction in conjunctiva of challenged guinea pigs compared with subcutaneously and non-immunized animals. The delivery of the chlamydial subunit vaccine to the ocular mucosa using a particulate carrier, such as BGs, induced both humoral and cellular immune responses. Further investigations are needed to improve the immunization scheme and dosage. 相似文献