TY  - JOUR
A1  - Righesso, L. A. R.
A1  - Terekhov, M.
A1  - Götz, H.
A1  - Ackermann, M.
A1  - Emrich, T.
A1  - Schreiber, L. M.
A1  - Müller, W. E. G.
A1  - Jung, J.
A1  - Rojas, J. P.
A1  - Al-Nawas, B.
T1  - Dynamic contrast-enhanced magnetic resonance imaging for monitoring neovascularization during bone regeneration — a randomized in vivo study in rabbits
JF  - Clinical Oral Investigations
N2  - Objectives
Micro-computed tomography (μ-CT) and histology, the current gold standard methods for assessing the formation of new bone and blood vessels, are invasive and/or destructive. With that in mind, a more conservative tool, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), was tested for its accuracy and reproducibility in monitoring neovascularization during bone regeneration. Additionally, the suitability of blood perfusion as a surrogate of the efficacy of osteoplastic materials was evaluated.

Materials and methods
Sixteen rabbits were used and equally divided into four groups, according to the time of euthanasia (2, 3, 4, and 6 weeks after surgery). The animals were submitted to two 8-mm craniotomies that were filled with blood or autogenous bone. Neovascularization was assessed in vivo through DCE-MRI, and bone regeneration, ex vivo, through μ-CT and histology.

Results
The defects could be consistently identified, and their blood perfusion measured through DCE-MRI, there being statistically significant differences within the blood clot group between 3 and 6 weeks (p = 0.029), and between the former and autogenous bone at six weeks (p = 0.017). Nonetheless, no significant correlations between DCE-MRI findings on neovascularization and μ-CT (r =−0.101, 95% CI [−0.445; 0.268]) or histology (r = 0.305, 95% CI [−0.133; 0.644]) findings on bone regeneration were observed.

Conclusions
These results support the hypothesis that DCE-MRI can be used to monitor neovascularization but contradict the premise that it could predict bone regeneration as well.
KW  - animal experimentation
KW  - bone regeneration
KW  - multiparametric magnetic resonance imaging
KW  - neovascularization, physiologic
KW  - tissue engineering
KW  - translational medical research
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-307614
SN  - 1432-6981
SN  - 1436-3771
VL  - 25
IS  - 10
ER  - 
TY  - JOUR
A1  - Ackermann, J.
A1  - Tacke, Reinhold
A1  - Wannagat, U.
A1  - Koke, U.
A1  - Meyer, F.
T1  - Derivate des 1-(4-Chlorphenyl)silacyclohexans mit 3-(Diethylamino)propyl- und 2-(Diethylamino)ethyl-Gruppierungen
T1  - Derivatives of 1-(4-Chlorophenyl)silacyclobexane with 3-(Diethylamino)propyl- and 2-(Diethylamino)etbyl Groups
N2  - Die Darstellung der Verbindungen 3a (sowie 3b) und 10, die sich vom 1-(4-Chlorphenyl)-1-(2~ diethylaminoethoxy)silacyclohexan (Sila-Chlorphencyclan, II a) ableiten, wird beschrieben. Die Verbindung 3 b wurde pharmakologisch und toxikologisch untersucht. Die biologischen Eigen· schaften von 3b wurden mit denen von Ila (sowie Chlorphencyclan) und seinem Hydrochiarid Ilb verglichen.
N2  - The preparation of the compounds 3a (and 3b) and 10, which derive from 1-(4-chlorophenyl)-1· (2-diethylaminoethoxy)silacyclohexane (sila-chlorophencyclane, II a). is described. Compound 3 b has been investigated pharmacologically and toxicologically. The biological properties of 3 b and those of ßa (and chlorophencyclane) and its hydrochloride Ilb are compared.
KW  - Anorganische Chemie
Y1  - 1979
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63621
ER  - 
TY  - JOUR
A1  - Ackermann, J.
A1  - Tacke, Reinhold
A1  - Wannagat, U.
A1  - Koke, U.
A1  - Meyer, F.
T1  - Sila-Analoga des Chlorphencyclans
T1  - Sila Analogues of Chlorphencyclane
N2  - Sila-Chlorphencyclan (8b), ein Sila-Analogon des Chlorphencyclans (8a), die Derivate 7 und 9, deren Ammoniumsalze 11, 12, 13 und 14b, das Hydrolyseprodukt 10 sowie die Vorstufen 3-6 wurden erstmalig dargestellt. Die neuen Verbindungen wurden in ihren chemischen und physikalischen Eigenschaften charakterisiert, ihre Struktur wurde sichergestellt. Chlorphencyclan, Sila-Chlorphencyclan und einige seiner Derivate wurden vergleichend pharmakologisch und toxikologisch untersucht.
N2  - Silachlorphencyclane (8b), a sila analogue of chlorphencyclane (8a), the derivatives 7 and 9, their amrnonium salts 11, 12, 13 and 14b, the product of hydro Iysis 10, as weil as the precursors ~ were synthesized. The new compounds were characterized by their chemical and physical properties. The pharmacological and toxicological properties of chlorphencyclane, silachlorphencyclane and some derivatives were investigated.
KW  - Anorganische Chemie
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63633
ER  -