Kuhn, Hans-Jürg

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Cell and Tissue Research"],["dc.bibliographiccitation.lastpage","13"],["dc.bibliographiccitation.volume","316"],["dc.contributor.author","Knabe, Wolfgang"],["dc.contributor.author","Washausen, Stefan"],["dc.contributor.author","Brunnett, G."],["dc.contributor.author","Kuhn, H. J."],["dc.date.accessioned","2018-11-07T10:49:47Z"],["dc.date.available","2018-11-07T10:49:47Z"],["dc.date.issued","2004"],["dc.description.abstract","Whether rhombomere-specific patterns of apoptosis exist in the developing hindbrain of vertebrates is under debate. We have investigated the sequence of apoptotic events in three-dimensionally reconstructed hindbrains of Tupaia belangeri (8- to 19-somite embryos). Apoptotic cells were identified by structural criteria and by applying an in situ tailing technique to visualize DNA fragmentation. Seven rhombomeres originated from three pro-rhombomeres. Among pre-migratory neural crest cells in the dorsal thirds of the neural folds, the earliest apoptotic concentrations appeared in the developing third rhombomere (r3). Dorsal apoptotic maxima then persisted in r3, extended from r3 to r2, and also arose in r5. Transverse apoptotic bands increased the total amount of apoptotic cells in odd-numbered rhombomeres first in r3 and, with a delay, also in r5. This sequence of apoptotic events was paralleled by an approximate rostrocaudal sequence of neural crest cell delamination from the even-numbered rhombomeres. Thus, large-scale apoptosis in r3 and r5 helped to establish crest-free zones that segregated streams of migrating neural crest cells adjacent to r2, r4, and r6. The sequence of apoptotic events observed in the dorsal thirds of rhombomeres matches that reported for the chick embryo. Other shared features are apoptotic peaks in the position of a circumscribed ventricular protrusion of fusing parts of the neural folds in r1 and r2, and Y-shaped apoptotic patterns composed of apoptotic maxima in the dorsal and lateral thirds of r1, r2, and r3. These rhombomere-specific patterns of apoptosis may therefore represent a conserved character, at least in amniotes."],["dc.identifier.doi","10.1007/s00441-004-0855-0"],["dc.identifier.isi","000220298800001"],["dc.identifier.pmid","14986099"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/48509"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0302-766X"],["dc.title","Rhombomere-specific patterns of apoptosis in the tree shrew Tupaia belangeri"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","PII S0165-0270(02)00247-9"],["dc.bibliographiccitation.firstpage","169"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Journal of Neuroscience Methods"],["dc.bibliographiccitation.lastpage","180"],["dc.bibliographiccitation.volume","121"],["dc.contributor.author","Knabe, Wolfgang"],["dc.contributor.author","Washausen, Stefan"],["dc.contributor.author","Brunnett, G."],["dc.contributor.author","Kuhn, H. R."],["dc.date.accessioned","2018-11-07T09:42:12Z"],["dc.date.available","2018-11-07T09:42:12Z"],["dc.date.issued","2002"],["dc.description.abstract","The present study demonstrates how, predominantly by external fiducials, histological serial sections used to reconstruct patterns of individually marked cellular events in large organs or whole embryos can be realigned with the help of 'reference series'. Resin-embedded embryos were cut at 1 mum and consecutive sections were alternately placed on two sets of slides. For cytological diagnosis and acquisition of embryonic contours, stained sections of the first series, termed 'working series', were scanned with the x 100 objective using 'Huge Image', a recently established image acquisition system. For acquisition of the contours of the resin block, adjacent unstained sections of the second series, termed 'reference series', were scanned with the x 5 objective. Thereafter, 'hybrid sections' were created which combined vectorized embryonic contours and cellular events taken from the working series with vectorized block contours taken from the reference series. For realignment, consecutive 'hybrid sections' were matched by best-fit of the block contours. Stacks of realigned 'hybrid sections' were shaped like truncated pyramids and, thus, reflected repeated 'trimming' of the resin block during the sectioning procedure. Among 266 'hybrid sections' at intervals of 8 gm, needed to reconstruct the brain of a 15-day-old embryo of Tupaia belangeri (Scandentia), internal fiducials were required five times for realigning a total of six adjacent truncated pyramids. Application of this method provided realistic reconstructions of the positions of apoptotic cells in the entire developing brain without the need of secondary introduction of external fiducials. (C) 2002 Elsevier Science B.V. All rights reserved."],["dc.identifier.doi","10.1016/S0165-0270(02)00247-9"],["dc.identifier.isi","000179968900006"],["dc.identifier.pmid","12468007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33903"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Science Bv"],["dc.relation.issn","0165-0270"],["dc.title","Use of 'reference series' to realign histological serial sections for three-dimensional reconstructions of the positions of cellular events in the developing brain"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","503"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","ANATOMY AND EMBRYOLOGY"],["dc.bibliographiccitation.lastpage","512"],["dc.bibliographiccitation.volume","207"],["dc.contributor.author","Knabe, Wolfgang"],["dc.contributor.author","Knerlich, F."],["dc.contributor.author","Washausen, Stefan"],["dc.contributor.author","Kietzmann, Thomas"],["dc.contributor.author","Siren, A. L."],["dc.contributor.author","Brunnett, G."],["dc.contributor.author","Kuhn, H. J."],["dc.contributor.author","Ehrenreich, Hannelore"],["dc.date.accessioned","2018-11-07T10:50:26Z"],["dc.date.available","2018-11-07T10:50:26Z"],["dc.date.issued","2004"],["dc.description.abstract","The expression patterns of erythropoietin (EPO) and its receptor (EPOR) were investigated in the midbrain and in adjacent parts of the synencephalon and hindbrain of embryonic C57Bl mice. On embryonic (E) day 8 (E8), virtually all neuroepithelial cells expressed EPOR. After neural tube closure, subsets of these cells downregulated EPOR. In contrast, radial glial cells were EPOR-immunolabeled from E11 onwards. Simultaneously, subpopulations of early developing neurons upregulated EPO and expressed HIF-1, known to transcriptionally activate EPO. Three-dimensional reconstructions revealed subpopulations of EPO-expressing neurons: (1) in the trigeminal mesencephalic nucleus (TMN), (2) at the rostral transition of the midbrain and synencephalon, (3) in the basal plate of the midbrain, (4) in the trigeminal motor nucleus, and (5) in the trigeminal principal sensory nucleus. In the rostral midbrain and synencephalon, EPO-immunoreactive neurons were attached to EPOR-expressing radial glial cells. The identity of radial glial cells was proven by their immunoreactivity for antibodies against astrocyte-specific glutamate transporter, brain lipid-binding protein, and nestin. From E12.5 onwards EPOR was downregulated in radial glial cells. Viable neurons of the TMN continued to express EPO and upregulated EPOR. Our findings provide new evidence that components of the EPO system are present in distinct locations of the embryonic brain and, by interactions between neurons and radial glial cells as well as among clustered TMN neurons, may contribute to its morphogenesis. Whether the observed expression patterns of EPO and EPOR may reflect EPO-mediated trophic and/or antiapoptotic effects on neurons is discussed."],["dc.identifier.doi","10.1007/s00429-003-0365-y"],["dc.identifier.isi","000220086500009"],["dc.identifier.pmid","14770308"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/48650"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0340-2061"],["dc.title","Expression patterns of erythropoietin and its receptor in the developing midbrain"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]