58 research outputs found
Adaptation of aphid stylectomy for analyses of proteins and mRNAs in barley phloem sap
Sieve tubes are transport conduits not only for photoassimilates but also for macromolecules and other compounds that are involved in sieve tube maintenance and systemic signalling. In order to gain sufficient amounts of pure phloem exudates from barley plants for analyses of the protein and mRNA composition, a previously described stylectomy set-up was optimized. Aphids were placed in sealed cages, which, immediately after microcauterization of the stylets, were flooded with water-saturated silicon oil. The exuding phloem sap was collected with a capillary connected to a pump. Using up to 30 plants and 600 aphids (Rhopalosiphum padi) in parallel, an average of 10 μl of phloem sap could be obtained within 6 h of sampling. In first analyses of the macromolecular content, eight so far unknown phloem mRNAs were identified by cDNA-amplified fragment length polymorphism. Transcripts in barley phloem exudates are related to metabolism, signalling, and pathogen defence, for example coding for a protein kinase and a pathogen- and insect-responsive WIR1A (wheat-induced resistance 1A)-like protein. Further, one-dimensional gel electrophoresis and subsequent partial sequencing by mass spectrometry led to the identification of seven major proteins with putative functions in stress responses and transport of mRNAs, proteins, and sugars. Two of the discovered proteins probably represent isoforms of a new phloem-mobile sucrose transporter. Notably, two-dimensional electrophoresis confirmed that there are >250 phloem proteins awaiting identification in future studies
Repression of Flowering by the miR172 Target SMZ
The flowering repressors SMZ and FLM, members of the AP-2 and MADS domain transcription factor families, unexpectedly work together to regulate flowering time via their effects on expression of the FT gene
Comparative analysis among the small RNA populations of source, sink and conductive tissues in two different plant-virus pathosystems
Conclusions: We compare for the first time the sRNA profile of four different tissues, including source, sink and conductive (phloem) tissues, in two plant-virus pathosystems. Our results indicate that antiviral silencing machinery in melon and cucumber acts mainly through DCL4. Upon infection, the total sRNA pattern in phloem remains unchanged in contrast to the rest of the analyzed tissues indicating a certain tissue-tropism to this polulation. Independently of the accumulation level of the vsRNAs both viruses were able to modulate the host sRNA pattern.We thank Dr A. Niehl for critical reading and helpful comments on the manuscript. This work was funded by a supporting program for the research from the Universidad Politecnica de Valencia (PAID-05-10), a grant BIO2011-25018 from the Spanish granting agency Direccion General de Investigacion Cientifica and the PROMETEO program 2011/003 from the Generalitat Valenciana. 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Low-molecular weight organic acids and peptides involved in the long-distance transport of trace metals
Einsatz von Telepräsenzsystemen in der Lehre - Transfer eines interprofessionellen Lehrmoduls zur digital gestützten Kommunikation in das Blockpraktikum "Innere Medizin" während der Covid-19-Pandemie
Objective: The contact restrictions caused by the Covid-19 pandemic fundamentally limit patient-centered teaching. To realize a patient-oriented education in the block training "Internal Medicine" at the University Hospital Halle (Saale) despite the challenges, the already established teaching module "Interprofessional Teleconsultation" was adapted. The short article outlines the interprofessional teaching module including first evaluation results and describes the adapted block training.Method: In the "Internal Medicine" block training, students in a lecture hall navigated a telepresence system, which was accompanied by a physician across the ward and conducted an anamnesis via video and audio transmission without actual patient contact. Results: Students, physicians, and patients were open-minded about this form of communication during the Covid-19 pandemic and quickly got accustomed to the use of the telepresence system. To be able to react to technical challenges (e.g. unstable connection between the communication partners), a careful preparation of the lecturers is necessary. Conclusion: In using a telepresence system, patient-oriented teaching of students in the block training "Internal Medicine" can be ensured with low-threshold technical effort during the Covid-19 pandemic. The telepresence system allows for the involvement of patients into teaching while adhering to the necessary hygiene measures. Despite technical challenges, the teaching format based on telepresence is suitable as an alternative to face-to-face teaching if actual patient contact is not possible.Zielsetzung: Die Kontakteinschränkungen durch die Covid-19-Pandemie beeinträchtigen die patientennahe Lehre grundlegend. Um trotz der besonderen Herausforderungen eine patientennahe Ausbildung im Blockpraktikum "Innere Medizin" am Universitätsklinikum Halle (Saale) zu realisieren, wurde das bereits etablierte Lehrmodul "Interprofessionelles Telekonsil" adaptiert. Der Kurzbeitrag skizziert das interprofessionelle Lehrmodul mit ersten Evaluationsergebnissen und beschreibt das adaptierte Blockpraktikum.Methodik: Im Blockpraktikum "Innere Medizin" navigieren die Studierenden von einem Hörsaal aus ein von einem*r Ärzt*in begleitetes Telepräsenzsystem über die Station und führen so via Video- und Audio-Übertragung ein Anamnesegespräch ohne unmittelbaren Patientenkontakt. Ergebnisse: Sowohl die Studierenden und Ärzt*innen als auch die Patient*innen standen dieser Form der Kommunikation während der Covid-19-Pandemie aufgeschlossen gegenüber und gewöhnten sich schnell an den Umgang mit dem Telepräsenzsystem. Um gegebenenfalls auf technische Herausforderungen (z.B. instabile Verbindung zwischen den Kommunikationspartner*innen) reagieren zu können, ist eine sorgfältige Vorbereitung der Dozent*innen notwendig. Schlussfolgerung: Durch den Einsatz des Telepräsenzsystems kann die patientennahe Ausbildung der Studierenden im Blockpraktikum "Innere Medizin" während der Covid-19-Pandemie mit niederschwelligem technischen Aufwand gewährleistet werden. Das Telepräsenzsystem ermöglicht dabei die Einbindung von Patient*innen in die studentische Lehre bei gleichzeitiger Einhaltung der erforderlichen Hygienemaßnahmen. Trotz technischer Herausforderungen ist das Lehrformat mit Telepräsenz als Alternative zur Präsenzlehre geeignet, wenn ein unmittelbarer Patientenkontakt nicht möglich ist
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