TY  - JOUR
A1  - Krämer, Stefanie D.
A1  - Schuhmann, Michael K.
A1  - Volkmann, Jens
A1  - Fluri, Felix
T1  - Deep brain stimulation in the subthalamic nucleus can improve skilled Forelimb movements and retune dynamics of striatal networks in a rat stroke model
JF  - International Journal of Molecular Sciences
N2  - Recovery of upper limb (UL) impairment after stroke is limited in stroke survivors. Since stroke can be considered as a network disorder, neuromodulation may be an approach to improve UL motor dysfunction. Here, we evaluated the effect of high-frequency stimulation (HFS) of the subthalamic nucleus (STN) in rats on forelimb grasping using the single-pellet reaching (SPR) test after stroke and determined costimulated brain regions during STN-HFS using 2-[\(^{18}\)F]Fluoro-2-deoxyglucose-([\(^{18}\)F]FDG)-positron emission tomography (PET). After a 4-week training of SPR, photothrombotic stroke was induced in the sensorimotor cortex of the dominant hemisphere. Thereafter, an electrode was implanted in the STN ipsilateral to the infarction, followed by a continuous STN-HFS or sham stimulation for 7 days. On postinterventional day 2 and 7, an SPR test was performed during STN-HFS. Success rate of grasping was compared between these two time points. [\(^{18}\)F]FDG-PET was conducted on day 2 and 3 after stroke, without and with STN-HFS, respectively. STN-HFS resulted in a significant improvement of SPR compared to sham stimulation. During STN-HFS, a significantly higher [\(^{18}\)F]FDG-uptake was observed in the corticosubthalamic/pallidosubthalamic circuit, particularly ipsilateral to the stimulated side. Additionally, STN-HFS led to an increased glucose metabolism within the brainstem. These data demonstrate that STN-HFS supports rehabilitation of skilled forelimb movements, probably by retuning dysfunctional motor centers within the cerebral network.
KW  - photothrombosis
KW  - experimental stroke
KW  - subthalamic nucleus
KW  - invasive electric stimulation
KW  - skilled forelimb movements
KW  - neuronal network
KW  - [18F]FDG positron emission tomography
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-312828
VL  - 23
IS  - 24
ER  - 
TY  - JOUR
A1  - Beer, Katharina
A1  - Helfrich-Förster, Charlotte
T1  - Post-embryonic Development of the Circadian Clock Seems to Correlate With Social Life Style in Bees
JF  - Frontiers in Cell and Developmental Biology
N2  - Social life style can influence many aspects of an animal’s daily life, but it has not yet been clarified, whether development of the circadian clock in social and solitary living bees differs. In a comparative study, with the social honey bee, Apis mellifera, and the solitary mason bee, Osmia bicornis, we now found indications for a differentially timed clock development in social and solitary bees. Newly emerged solitary bees showed rhythmic locomotion right away and the number of neurons in the brain that produce the clock component pigment-dispersing factor (PDF) did not change during aging of the adult solitary bee. Honey bees on the other hand, showed no circadian locomotion directly after emergence and the neuronal clock network continued to grow after emergence. Social bees appear to emerge at an early developmental stage at which the circadian clock is still immature, but bees are already able to fulfill in-hive tasks.
KW  - social
KW  - honey bee
KW  - solitary bee
KW  - circadian clock
KW  - activity rhythm
KW  - neuronal network
KW  - development
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-216450
SN  - 2296-634X
VL  - 8
ER  -