Steffens, Heinz

[["dc.bibliographiccitation.artnumber","219"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Scientific Reports"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Wegner, Waja"],["dc.contributor.author","Mott, Alexander C."],["dc.contributor.author","Grant, Seth G. N."],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Willig, Katrin I."],["dc.date.accessioned","2019-07-09T11:45:13Z"],["dc.date.available","2019-07-09T11:45:13Z"],["dc.date.issued","2018"],["dc.description.abstract","The post-synaptic density (PSD) is an electron dense region consisting of ~1000 proteins, found at the postsynaptic membrane of excitatory synapses, which varies in size depending upon synaptic strength. PSD95 is an abundant scaffolding protein in the PSD and assembles a family of supercomplexes comprised of neurotransmitter receptors, ion channels, as well as signalling and structural proteins. We use superresolution STED (STimulated Emission Depletion) nanoscopy to determine the size and shape of PSD95 in the anaesthetised mouse visual cortex. Adult knock-in mice expressing eGFP fused to the endogenous PSD95 protein were imaged at time points from 1 min to 6 h. Superresolved large assemblies of PSD95 show different sub-structures; most large assemblies were ring-like, some horse-shoe or figure-8 shaped, and shapes were continuous or made up of nanoclusters. The sub-structure appeared stable during the shorter (minute) time points, but after 1 h, more than 50% of the large assemblies showed a change in sub-structure. Overall, these data showed a sub-morphology of large PSD95 assemblies which undergo changes within the 6 hours of observation in the anaesthetised mouse."],["dc.identifier.doi","10.1038/s41598-017-18640-z"],["dc.identifier.pmid","29317733"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15060"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59184"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation","info:eu-repo/grantAgreement/EC/FP7/241498/EU//EUROSPIN"],["dc.relation.issn","2045-2322"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","610"],["dc.title","In vivo STED microscopy visualizes PSD95 sub-structures and morphological changes over several hours in the mouse visual cortex."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","203"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","PHYSIOLOGICAL RESEARCH"],["dc.bibliographiccitation.lastpage","214"],["dc.bibliographiccitation.volume","61"],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Dibaj, Payam"],["dc.contributor.author","Schomburg, Eike D."],["dc.date.accessioned","2018-11-07T09:15:11Z"],["dc.date.available","2018-11-07T09:15:11Z"],["dc.date.issued","2012"],["dc.description.abstract","Electrophysiological investigations in mice, particularly with altered myelination, require reference data of the nerve conduction velocity (CV). CVs of different fibre groups were determined in the hindlimb of anaesthetized adult mice. Differentiation between afferent and efferent fibres was performed by recording at dorsal roots and stimulating at ventral roots, respectively. Correspondingly, recording or stimulation was performed at peripheral hindlimb nerves. Stimulation was performed with graded strength to differentiate between fibre groups. CVs of the same fibre groups were different in different nerves of the hindlimb. CVs for motor fibres were for the tibial nerve (Tib) 38.5 +/- 4.0 m/s (A gamma: 16.7 +/- 3.0 m/s), the sural nerve (Sur) 39.3 +/- 3.1 m/s (12.0 +/- 0.8 m/s) and the common peroneal nerve (Per) 46.7 +/- 4.7 m/s (22.2 +/- 4.4 m/s). CVs for group I afferents were 47.4 +/- 3.1 m/s (Tib), 43.8 +/- 3.8 m/s (Sur), 55.2 +/- 6.1 m/s (Per) and 42.9 +/- 4.3 m/s for the posterior biceps (PB). CVs of higher threshold afferents, presumably muscle and cutaneous, cover a broad range and do not really exhibit nerve specific differences. Ranges are for group II 22-38 m/s, for group III 9-19 m/s, and for group IV 0.8-0.9 m/s. Incontrovertible evidence was found for the presence of motor fibres in the sural nerve. The results are useful as references for further electrophysiological investigations particularly in genetically modified mice with myelination changes."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [SCHO 37/16]"],["dc.identifier.isi","000306507400010"],["dc.identifier.pmid","22292724"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/27616"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Acad Sciences Czech Republic, Inst Physiology"],["dc.relation.issn","0862-8408"],["dc.title","In Vivo Measurement of Conduction Velocities in Afferent and Efferent Nerve Fibre Groups in Mice"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","693"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Neurological Research"],["dc.bibliographiccitation.lastpage","702"],["dc.bibliographiccitation.volume","37"],["dc.contributor.author","Dibaj, Payam"],["dc.contributor.author","Schomburg, Eike D."],["dc.contributor.author","Steffens, Heinz"],["dc.date.accessioned","2018-11-07T09:54:21Z"],["dc.date.available","2018-11-07T09:54:21Z"],["dc.date.issued","2015"],["dc.description.abstract","Objectives: In the SOD1G93A mouse model of amyotrophic lateral sclerosis (ALS), a selective degeneration of fast-fatigable motor units and consequently an early decline of contractile force in individual fast-twitch muscles have been observed in the preclinical stage. However, most human muscles include fast and slow motor units. Gastrocnemius-soleus group (GS) contains such a mixture of units. Methods: We have investigated changes in the mechanical properties of GS at different SOD1G93A stages in mice. For this purpose, the tibial nerve was repetitively stimulated with rectangular pulses and the force of GS twitches was recorded using a strain gauge fixed to the Achilles tendon. Results: Isometric and tetanic force were attenuated but not before the first clinical signs developed. However, already at preclinical stages, single twitches showed a slower decay compared to control. Consequently, fusion of GS twitches occurred at lower stimulus rates. Furthermore, already preclinically, the temporal course of successive twitch amplitudes changed during repetitive stimulation at increasing rates. The peak amplitudes as well as the potentiation following decay (fatigue) were lower in preclinical mice than in control. Discussion: The time-lapse analysis of the contractile pattern as well as of the twitch configuration of the mixed muscle GS have revealed distinctive differences between wild-type controls and preclinical SOD1G93A mice. It would be of interest to know whether these preclinical changes are also detectable in ALS patients."],["dc.identifier.doi","10.1179/1743132815Y.0000000039"],["dc.identifier.isi","000356891600006"],["dc.identifier.pmid","25917373"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/36519"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Taylor & Francis Ltd"],["dc.relation.issn","1743-1328"],["dc.relation.issn","0161-6412"],["dc.title","Contractile characteristics of gastrocnemius-soleus muscle in the SOD1G93A ALS mouse model"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","S2211124721005386"],["dc.bibliographiccitation.firstpage","109192"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Cell Reports"],["dc.bibliographiccitation.volume","35"],["dc.contributor.author","Willig, Katrin I."],["dc.contributor.author","Wegner, Waja"],["dc.contributor.author","Müller, Antonia"],["dc.contributor.author","Calvet-Fournier, Valérie"],["dc.contributor.author","Steffens, Heinz"],["dc.date.accessioned","2021-07-05T15:00:59Z"],["dc.date.available","2021-07-05T15:00:59Z"],["dc.date.issued","2021"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.1016/j.celrep.2021.109192"],["dc.identifier.pii","S2211124721005386"],["dc.identifier.pmid","34077731"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/87954"],["dc.identifier.url","https://mbexc.uni-goettingen.de/literature/publications/262"],["dc.language.iso","en"],["dc.notes.intern","DOI Import DOI-Import GROB-441"],["dc.relation","EXC 2067: Multiscale Bioimaging"],["dc.relation.issn","2211-1247"],["dc.relation.workinggroup","RG Willig (Optical Nanoscopy in Neuroscience)"],["dc.rights","CC BY-NC-ND 4.0"],["dc.title","Multi-label in vivo STED microscopy by parallelized switching of reversibly switchable fluorescent proteins"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","eabf2806"],["dc.bibliographiccitation.issue","24"],["dc.bibliographiccitation.journal","Science Advances"],["dc.bibliographiccitation.volume","7"],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Mott, Alexander C."],["dc.contributor.author","Li, Siyuan"],["dc.contributor.author","Wegner, Waja"],["dc.contributor.author","Švehla, Pavel"],["dc.contributor.author","Kan, Vanessa W. Y."],["dc.contributor.author","Wolf, Fred"],["dc.contributor.author","Liebscher, Sabine"],["dc.contributor.author","Willig, Katrin I."],["dc.date.accessioned","2021-07-05T14:57:45Z"],["dc.date.available","2021-07-05T14:57:45Z"],["dc.date.issued","2021"],["dc.description.abstract","Excitatory synapses on dendritic spines of pyramidal neurons are considered a central memory locus. To foster both continuous adaption and the storage of long-term information, spines need to be plastic and stable at the same time. Here, we advanced in vivo STED nanoscopy to superresolve distinct features of spines (head size and neck length/width) in mouse neocortex for up to 1 month. While LTP-dependent changes predict highly correlated modifications of spine geometry, we find both, uncorrelated and correlated dynamics, indicating multiple independent drivers of spine remodeling. The magnitude of this remodeling suggests substantial fluctuations in synaptic strength. Despite this high degree of volatility, all spine features exhibit persistent components that are maintained over long periods of time. Furthermore, chronic nanoscopy uncovers structural alterations in the cortex of a mouse model of neurodegeneration. Thus, at the nanoscale, stable dendritic spines exhibit a delicate balance of stability and volatility."],["dc.identifier.doi","10.1126/sciadv.abf2806"],["dc.identifier.pmid","34108204"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/87727"],["dc.identifier.url","https://mbexc.uni-goettingen.de/literature/publications/265"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-441"],["dc.relation","EXC 2067: Multiscale Bioimaging"],["dc.relation.eissn","2375-2548"],["dc.relation.workinggroup","RG Willig (Optical Nanoscopy in Neuroscience)"],["dc.relation.workinggroup","RG Wolf"],["dc.rights","CC BY-NC 4.0"],["dc.title","Stable but not rigid: Chronic in vivo STED nanoscopy reveals extensive remodeling of spines, indicating multiple drivers of plasticity"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","44"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Neuroscience Research"],["dc.bibliographiccitation.lastpage","54"],["dc.bibliographiccitation.volume","70"],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Schomburg, Eike D."],["dc.date.accessioned","2018-11-07T08:56:19Z"],["dc.date.available","2018-11-07T08:56:19Z"],["dc.date.issued","2011"],["dc.description.abstract","For further evaluation of opioidergic spinal motor functions the action of the mu-opioid receptor agonist DAMGO was tested on transmission in different non-nociceptive and nociceptive spinal reflex pathways from flexor reflex afferents (FRA), and in non-FRA reflex pathways in spinal cats. The action of DAMGO was complex, not following a simple pattern with selective depression of nociceptive pathways compared to non-nociceptive ones. Monosynaptic reflexes of the flexor posterior biceps semitendinosus (PBSt) and transmission in nociceptive as well as non-nociceptive excitatory FRA pathways to PBSt were depressed, while the specific excitatory nociceptive non-FRA pathway from the central foot pad to foot extensors was mainly not depressed but rather facilitated by DAMGO. DAMGO caused a facilitation of monosynaptic reflexes to the extensor gastrocnemius soleus (GS) and partly a reversal of inhibitory to excitatory conditioning effects from cutaneous afferents to GS. FRA interneurones could show either an increase or a cessation of their spontaneous activity, but responsiveness to nociceptive and non-nociceptive afferent activation was blocked by DAMGO. The main DAMGO action is generated via interneuronal systems rather than on motoneurones themselves. The results indicate that opioidergic spinal functions are extensively involved in spinal motor control exceeding a mere suppression of nociceptive motor withdrawal reactions. (C) 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [SCHO 37/16]"],["dc.identifier.doi","10.1016/j.neures.2011.01.011"],["dc.identifier.isi","000291179500008"],["dc.identifier.pmid","21276826"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/23120"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Ireland Ltd"],["dc.relation.issn","0168-0102"],["dc.title","Spinal motor actions of the mu-opioid receptor agonist DAMGO in the cat"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","551"],["dc.bibliographiccitation.issue","6068"],["dc.bibliographiccitation.journal","Science"],["dc.bibliographiccitation.lastpage","551"],["dc.bibliographiccitation.volume","335"],["dc.contributor.author","Berning, Sebastian"],["dc.contributor.author","Willig, Katrin I."],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Dibaj, Payam"],["dc.contributor.author","Hell, Stefan"],["dc.date.accessioned","2017-09-07T11:49:00Z"],["dc.date.available","2017-09-07T11:49:00Z"],["dc.date.issued","2012"],["dc.description.abstract","We demonstrated superresolution optical microscopy in a living higher animal. Stimulated emission depletion (STED) fluorescence nanoscopy reveals neurons in the cerebral cortex of a mouse with <70-nanometer resolution. Dendritic spines and their subtle changes can be observed at their relevant scales over extended periods of time."],["dc.identifier.doi","10.1126/science.1215369"],["dc.identifier.gro","3142583"],["dc.identifier.isi","000299769200034"],["dc.identifier.pmid","22301313"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8950"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0036-8075"],["dc.title","Nanoscopy in a Living Mouse Brain"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","605"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","The Journal of Physiology"],["dc.bibliographiccitation.lastpage","613"],["dc.bibliographiccitation.volume","536"],["dc.contributor.author","Schomburg, Eike D."],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Wada, N."],["dc.date.accessioned","2018-11-07T08:32:31Z"],["dc.date.available","2018-11-07T08:32:31Z"],["dc.date.issued","2001"],["dc.description.abstract","1. Nociceptive reflex pathways to foot extensors were investigated with particular attention given to those not following a flexor reflex (FRA) or withdrawal pattern. 2. In anaemically decapitated, high spinal paralysed cats nociceptive afferents of the foot pad were activated by noxious radiant heat (48-60 degreesC), while for comparison non-nociceptive afferents were activated by weak mechanical stimulation of the skin or graded electrical nerve stimulation. The reflex action of the afferents on hindlimb motoneurones, innervating plantaris and intrinsic foot extensors (tibial nerve), was investigated by intracellular recording, by monosynaptic reflex testing and by recording of neurograms during fictive locomotion. A possible descending control of the nociceptive and non-nociceptive pathways was tested by application of opioidergic and monoaminergic compounds. 3. Beside the typical FRA pattern evoked in the majority of hindlimb motoneurone pools by nociceptive afferents from different skin areas of the foot, the results revealed parallel excitatory and inhibitory nociceptive reflex pathways from the central pad and partly from the toe pads to foot extensors. The excitatory pathways, which did not follow the FRA pattern, were predominantly to plantaris and intrinsic foot extensors. They were distinctly less depressed by opioids and monoaminergic compounds than FRA pathways. 4. While the nociceptive FRA pathways have a general nocifensive withdrawal function, the nociceptive excitatory non-FRA pathway to the foot extensors causes a movement of the affected area towards the stimulus or at least a resistance against the stimulus, i.e. it mediates a positive feedback."],["dc.identifier.doi","10.1111/j.1469-7793.2001.0605c.xd"],["dc.identifier.isi","000171807700025"],["dc.identifier.pmid","11600693"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/17357"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Cambridge Univ Press"],["dc.relation.issn","0022-3751"],["dc.title","Parallel nociceptive reflex pathways with negative and positive feedback functions to foot extensors in the cat"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","Acta Physiologica"],["dc.bibliographiccitation.volume","211"],["dc.contributor.author","Schomburg, Eike D."],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Dibaj, Payam"],["dc.contributor.author","Sears, Thomas A."],["dc.date.accessioned","2018-11-07T09:36:48Z"],["dc.date.available","2018-11-07T09:36:48Z"],["dc.date.issued","2014"],["dc.format.extent","32"],["dc.identifier.isi","000349466000033"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/32698"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.publisher.place","Hoboken"],["dc.relation.issn","1748-1716"],["dc.relation.issn","1748-1708"],["dc.title","Chronic muscle pain provokes bilateral flexion reflex pattern in the feline spinal cord"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","11781"],["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Scientific reports"],["dc.bibliographiccitation.lastpage","10"],["dc.bibliographiccitation.volume","7"],["dc.contributor.author","Wegner, Waja"],["dc.contributor.author","Ilgen, Peter"],["dc.contributor.author","Gregor, Carola"],["dc.contributor.author","van Dort, Joris"],["dc.contributor.author","Mott, Alexander C."],["dc.contributor.author","Steffens, Heinz"],["dc.contributor.author","Willig, Katrin I."],["dc.date.accessioned","2019-07-09T11:44:29Z"],["dc.date.available","2019-07-09T11:44:29Z"],["dc.date.issued","2017-09-18"],["dc.description.abstract","The study of proteins in dendritic processes within the living brain is mainly hampered by the diffraction limit of light. STED microscopy is so far the only far-field light microscopy technique to overcome the diffraction limit and resolve dendritic spine plasticity at superresolution (nanoscopy) in the living mouse. After having tested several far-red fluorescent proteins in cell culture we report here STED microscopy of the far-red fluorescent protein mNeptune2, which showed best results for our application to superresolve actin filaments at a resolution of ~80 nm, and to observe morphological changes of actin in the cortex of a living mouse. We illustrate in vivo far-red neuronal actin imaging in the living mouse brain with superresolution for time periods of up to one hour. Actin was visualized by fusing mNeptune2 to the actin labels Lifeact or Actin-Chromobody. We evaluated the concentration dependent influence of both actin labels on the appearance of dendritic spines; spine number was significantly reduced at high expression levels whereas spine morphology was normal at low expression."],["dc.identifier.doi","10.1038/s41598-017-11827-4"],["dc.identifier.pmid","28924236"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14798"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59023"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","2045-2322"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","573"],["dc.subject.ddc","612"],["dc.title","In vivo mouse and live cell STED microscopy of neuronal actin plasticity using far-red emitting fluorescent proteins."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]