University of Groningen

About: University of Groningen is a education organization based out in Groningen, Groningen, Netherlands. It is known for research contribution in the topics: Population & Context (language use). The organization has 36346 authors who have published 69116 publications receiving 2940370 citations. The organization is also known as: Rijksuniversiteit Groningen & RUG.

Natural Course of Schizophrenic Disorders: A 15-Year Followup of a Dutch Incidence Cohort

Abstract: Data are presented on the 15-year natural course of schizophrenia and other nonaffective functional psychoses in a cohort of 82 first-contact cases from a circumscribed area in the Netherlands. The subjects were suffering from functional psychosis with International Classification of Diseases-Ninth Revision (ICD-9) diagnoses 295, 297, or 298.3-9 (broad definition of schizophrenia) on entry. Standardized assessments of psychopathology, psychological impairments, negative symptomatology, social disability, and use of mental healthcare were used. The study reveals a pattern of chronicity and relapses with a high risk of suicide: Two-thirds of the subjects had at least one relapse and after each relapse 1 of 6 subjects did not remit from the episode; 1 of 10 committed suicide; and 1 of 7 had at least one episode with affective psychotic symptoms that started on average 6 years after the onset of the schizophrenic disorder. Diagnoses were reclassified in five patients, according to DSM-III-R criteria for a bipolar disorder. The predictive power--in terms of time in psychosis and in partial or full remission--of demographic, illness, and treatment variables at onset of the illness was very limited. Insidious onset and delays in mental health treatment are risk factors that predict a longer duration of first or subsequent episodes. The importance of mental health treatment in regard to outcome is probably subject to change because an early warning and intervention strategy could prevent further damage and deterioration. Our data support the need for an adequate relapse prevention program as a priority for our mental health services.

Reversible Optical Transcription of Supramolecular Chirality into Molecular Chirality

Abstract: In nature, key molecular processes such as communication, replication, and enzyme catalysis all rely on a delicate balance between molecular and supramolecular chirality. Here we report the design, synthesis, and operation of a reversible, photoresponsive, self-assembling molecular system in which molecular and supramolecular chirality communicate. It shows exceptional stereoselectivity upon aggregation of the molecules during gel formation with the solvent. This chirality is locked by photochemical switching, a process that is subsequently used to induce an inverted chiral supramolecular assembly as revealed by circular dichroism spectroscopy. The optical switching between different chiral aggregated states and the interplay of molecular and supramolecular chirality offer attractive new prospects for the development of molecular memory systems and smart functional materials.

LysM, a widely distributed protein motif for binding to (peptido)glycans

Abstract: Bacteria retain certain proteins at their cell envelopes by attaching them in a non-covalent manner to peptidoglycan, using specific protein domains, such as the prominent LysM (Lysin Motif) domain More than 4000 (Pfam PF01476) proteins of both prokaryotes and eukaryotes have been found to contain one or more Lysin Motifs Notably, this collection contains not only truly secreted proteins, but also (outer-)membrane proteins, lipoproteins or proteins bound to the cell wall in a (non-)covalent manner The motif typically ranges in length from 44 to 65 amino acid residues and binds to various types of peptidoglycan and chitin, most likely recognizing the N-acetylglucosamine moiety Most bacterial LysM-containing proteins are peptidoglycan hydrolases with various cleavage specificities Binding of certain LysM proteins to cells of Gram-positive bacteria has been shown to occur at specific sites, as binding elsewhere is hindered by the presence of other cell wall components such as lipoteichoic acids Interestingly, LysM domains of certain plant kinases enable the plant to recognize its symbiotic bacteria or sense and induce resistance against fungi This interaction is triggered by chitin-like compounds that are secreted by the symbiotic bacteria or released from fungi, demonstrating an important sensing function of LysMs

Oral Biofilm Architecture on Natural Teeth

Abstract: Periodontitis and caries are infectious diseases of the oral cavity in which oral biofilms play a causative role. Moreover, oral biofilms are widely studied as model systems for bacterial adhesion, biofilm development, and biofilm resistance to antibiotics, due to their widespread presence and accessibility. Despite descriptions of initial plaque formation on the tooth surface, studies on mature plaque and plaque structure below the gum are limited to landmark studies from the 1970s, without appreciating the breadth of microbial diversity in the plaque. We used fluorescent in situ hybridization to localize in vivo the most abundant species from different phyla and species associated with periodontitis on seven embedded teeth obtained from four different subjects. The data showed convincingly the dominance of Actinomyces sp., Tannerella forsythia, Fusobacterium nucleatum, Spirochaetes, and Synergistetes in subgingival plaque. The latter proved to be new with a possibly important role in host-pathogen interaction due to its localization in close proximity to immune cells. The present study identified for the first time in vivo that Lactobacillus sp. are the central cells of bacterial aggregates in subgingival plaque, and that Streptococcus sp. and the yeast Candida albicans form corncob structures in supragingival plaque. Finally, periodontal pathogens colonize already formed biofilms and form microcolonies therein. These in vivo observations on oral biofilms provide a clear vision on biofilm architecture and the spatial distribution of predominant species.