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3.
Clin Neuroradiol ; 32(2): 325-343, 2022 Jun.
Article in English | MEDLINE | ID: mdl-34581828

ABSTRACT

PURPOSE: Angiographic techniques have gained increasing importance in suspected vascular disease of the spinal cord. This demands an advanced understanding of spinal cord blood vessel anatomy and its embryologically founded broad spectrum of variations. The aim of this study was to improve knowledge on contentious issues concerning the development of spinal cord arterial supply in higher mammals and to offer visual information of high didactic value. METHODS: The prenatal development was examined in cattle, using multiplanar high-resolution microangiography of injected specimens and microscopic sections. The gestational ages of the 15 specimens were between the late embryonic and the early fetal period (5-11 weeks). Microangiography of the human spinal cord from an earlier published study were used to envisage an adult arterial vascularization pattern in higher mammals. RESULTS: Establishment of the unpaired anterior spinal artery (ASA) goes through two procedures of reconfiguration until achieving its final design. Regression of the primarily established anteromedian tract is observed in cattle fetuses of 9-10 weeks. Return to the ontogenetic disposition of bilateral symmetry and a burst of vascularization from all parts of the spinal meninges follow and include the anterior median fissure as a preferred vascular pathway. Large sulcal/central arteries longitudinally anastomosing between each other emerge on both sides of the midline. The embryological pattern of exclusive peripheral medullary supply must have been converted into a combined system of predominant central (centrifugal) supply of the enlargements before a final unpaired ASA can be reconstructed. CONCLUSION: Previous investigators focused on the early embryonic development of spinal cord arteries and missed the profound remodeling of the vascular architecture in the early fetal period.


Subject(s)
Angiography , Spinal Cord , Animals , Cattle , Female , Gestational Age , Humans , Mammals , Pregnancy , Spinal Cord/blood supply , Spinal Cord/diagnostic imaging , Vertebral Artery
4.
Hautarzt ; 72(10): 878-891, 2021 Oct.
Article in German | MEDLINE | ID: mdl-33835190

ABSTRACT

Trichophyton (T.) tonsurans is considered as the main causative agent of tinea gladiatorum (ringworm) in contact and martial arts worldwide and regularly leads to outbreaks. In the national wrestling squad in Leipzig, dermatophytoses occurred frequently and recurrently in children and adolescents for over a 2-year period. The wrestlers came to the dermatologist's office for clinical examination and sampling. Dermal scales and hair roots as well as smears were examined mycologically with fluorescence optical preparation, fungal culture, and polymerase chain reaction (PCR) for dermatophyte DNA. Sequencing of the dermatophyte rDNA served as culture confirmation test. Environmental investigations in the wrestler training center included contact cultures and smears from surfaces, in particular from the mats. T. tonsurans was culturally and/or with PCR detectable in 21 out of 25 children and adolescents plus one trainer. T. tonsurans grew in one of ten contact cultures of mats and floors in the wrestling training center, and T. interdigitale was found in another culture. Smears from the mats resulted in a culture of T. tonsurans detection twice. The PCR was positive for T. tonsurans three times. Within 14 days, T. tonsurans developed small, flat, radiating, granular and white-colored colonies with a mahogany-brown reverse side on the fungal culture media. The sequencing of the internal transcribed spacer (ITS) region of the rDNA and the translation elongation factor 1 α (TEF 1 α) gene confirmed the species T. tonsurans in all cases. T. interdigitale that was found from a mat was also identified by sequencing. Eight T. tonsurans strains were subjected to in vitro susceptibility testing to terbinafine. All isolates were sensitive to terbinafine in vitro with minimal inhibitory concentrations of ≤ 0.1 µg/ml.


Subject(s)
Trichophyton , Wrestling , Adolescent , Arthrodermataceae , Child , Disease Outbreaks , Humans , Terbinafine
5.
Chemistry ; 25(41): 9624-9628, 2019 Jul 22.
Article in English | MEDLINE | ID: mdl-31094025

ABSTRACT

A gold(I)-catalyzed cascade cyclization-alkynylation of allenoates using alkynyl bromide to generate ß-alkynyl-γ-butenolides was investigated. Whereas alkynyl iodides afforded significant amounts of the homo-coupling of two lactone units, alkynyl bromides led to a selective reaction, and a broad functional group tolerance was observed. Under the optimized reaction conditions, it was possible to directly synthesize a large range of ß-alkynyl-γ-butenolides in moderate to good yields without the need for any external oxidant.

6.
Org Lett ; 21(5): 1422-1425, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30785299

ABSTRACT

By using silver complexes with bulky ligands such as DavePhos or N-heterocyclic carbenes, propargylic alcohols are smoothly converted with CO2 into a unique class of unexplored cyclic alkylidene carbonates. These systems, for the first time, also achieve the direct carboxylative cyclization of primary propargylic alcohols. The silver-DavePhos catalyst is further applied for the bis-carboxylative cyclization of primary propargyl derivatives, thereby providing an effective route to a series of previously inaccessible and industrially relevant α-alkylidene cyclic carbonates.

7.
J Inorg Biochem ; 159: 70-5, 2016 06.
Article in English | MEDLINE | ID: mdl-26921720

ABSTRACT

Prochloron, a blue-green algae belonging to ancient prokaryotes, produces, like other cyanobacteria, cyclic pseudo-peptides, which are also found in its obligate symbiont ascidiae (Lissoclinum patellum). Although research has focused for some time on the putative metabolic function of these cyclic peptides, to date it is still not understood. Their role might be connected to the increased concentrations of divalent metal ions, especially Cu(II), found in ascidiae. Dinuclear copper(II) complexes of cyclic pseudo-peptides revealed a broad hydrolytic capacity, including carboanhydrase and phosphatase activity. This study reports their ß-lactamase as well as α- and ß-glycosidase activity with kcat=(11.34±0.91)ˑ10(-4)s(-1) for ß-lactamase, kcat=(1.55±0.13)ˑ10(-4)s(-1) for α-glycosidase and kcat=(1.22±0.09)ˑ10(-4)s(-1) for ß-glycosidase activity.


Subject(s)
Bacterial Proteins/chemistry , Copper/chemistry , Cyanobacteria/enzymology , Glycoside Hydrolases/chemistry , Peptides, Cyclic/chemistry , beta-Lactamases/chemistry , Animals
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