Kraepelin’s views on obsessive neurosis: a comparison with DSM-5 criteria for obsessive-compulsive disorder

Emil Kraepelin (1856-1926) is considered one of the founders of modern psychiatric nosology. However, his conceptualization of obsessive-compulsive phenomena is relatively understudied. In this article, we compare and contrast excerpts from the eighth edition (1909-1915) of Kraepelin’s Textbook of Clinical Psychiatry focusing on what Kraepelin called “obsessive neurosis” and related “original pathological conditions” with the current DSM-5 criteria for obsessive-compulsive disorder (OCD). Consistently with DSM-5 OCD, Kraepelin described obsessive neurosis as characterized by obsessive ideas, compulsive acts, or both together. His detailed descriptions of these symptoms are broadly coherent with their characterization in DSM-5, which is also true for the differential diagnoses he provided. He also mentioned cases illustrating decreased insight into symptoms and association with tic disorders. In conclusion, Kraepelin’s experience, which reflects decades of consistent clinical work, may help validate current ideas and explain how the current conceptualization has emerged and developed. Even though one can hardly say that the classification laid out in DSM-5 goes back to Kraepelin’s views directly, it still is true that Kraepelin played an outstanding role in systematizing psychiatric diagnostic criteria in general, and provided a major contribution to the conceptual history of OCD

Structures of the nucleotide-binding domain of the human ABCB6 transporter and its complexes with nucleotides.

The human ATP-binding cassette (ABC) transporter ABCB6 is involved in haem-precursor transport across the mitochondrial membrane. The crystal structure of its nucleotide-binding domain (NBD) has been determined in the apo form and in complexes with ADP, with ADP and Mg(2+) and with ATP at high resolution. The overall structure is L-shaped and consists of two lobes, consistent with other reported NBD structures. Nucleotide binding is mediated by the highly conserved Tyr599 and the Walker A motif, and induces notable structural changes. Structural comparison with other structurally characterized NBDs and full-length ABC transporters gives the first insight into the possible catalytic mechanism of ABCB6 and the role of the N-terminal helix alpha(1) in full-length ABCB6

Light Trapping with Waveguide Modes in Periodically Nanostructured Thin-Film Silicon Solar Cells

Thin-film silicon solar cells offer the advantages of low material and manufacturing costs. In order to enhance the absorptance of incident light in the optically thin silicon absorber layer, this technology requires advanced light-trapping concepts. Conventional devices apply randomly textured transparent conductive oxide substrates serving as light-scattering front contacts as well as reflective light-scattering metal back contacts. In recent years, several novel light-trapping concepts based on periodic nanostructures and periodically nanotextured interfaces, such as grating couplers, photonic crystals or plasmonic reflection gratings, have been suggested and prototyped. For these concepts the absorption of incident light in the solar cells is enhanced by light-coupling to waveguide modes which are supported by the silicon absorber layer of the solar cells but can be excited at the same time by incident light.In this contribution, our recent progress on light-trapping in periodically structured prototype thin-film silicon solar cells made of hydrogenated amorphous silicon and hydrogenated microcrystalline silicon is presented. The prototype solar cells show a superior light-trapping effect compared to solar cells applying the conventional random texture for light-trapping. To better understand this improved light-trapping effect, the coupling of incident light to waveguide modes in periodically nanostructured thin-film silicon solar cells is analysed in-depth. Therefore, the shape of the grating structure and the geometry of the unit cell of the two-dimensional periodic grating structure of the thin-film silicon solar cells are varied systematically and the excitation of the waveguide modes is studied. To characterize the coupling of incident light to individual waveguide modes, advanced characterization techniques, i.e. angular and polarization dependent spectral response measurements of resolution below 3 nm as well as near-field scanning optical microscopy, are developed and employed. Finally, based on our study new routes for improved designs of the periodic nanostructure of thin-film silicon solar cells will be outlined

Structural basis for complex formation between human IRSp53 and the translocated intimin receptor Tir of enterohemorrhagic E. coli.

Actin assembly beneath enterohemorrhagic E. coli (EHEC) attached to its host cell is triggered by the intracellular interaction of its translocated effector proteins Tir and EspF(U) with human IRSp53 family proteins and N-WASP. Here, we report the structure of the N-terminal I-BAR domain of IRSp53 in complex with a Tir-derived peptide, in which the homodimeric I-BAR domain binds two Tir molecules aligned in parallel. This arrangement provides a protein scaffold linking the bacterium to the host cell's actin polymerization machinery. The structure uncovers a specific peptide-binding site on the I-BAR surface, conserved between IRSp53 and IRTKS. The Tir Asn-Pro-Tyr (NPY) motif, essential for pedestal formation, is specifically recognized by this binding site. The site was confirmed by mutagenesis and in vivo-binding assays. It is possible that IRSp53 utilizes the NPY-binding site for additional interactions with as yet unknown partners within the host cell