Operationalization of the dimensions of a classification of mental functions

Background: So far there has been no empirically proven taxonomy of mental functions which summarizes brain functions from a neuropsychological perspective. The classification of mental functions by Pöppel (1993, 1997) explains the correlation of the elementary functions from a neuropsychological point of view, based on a psychology of time. He distinguishes four levels of cognition: the cognition of simultaneity, of succession, of the subjective present, and of duration. These levels of cognition are based on two different brain mechanisms of temporal organization: a high-frequency mechanism that provides discrete systemic conditions of 30ms, within which all information that is processed separately in the brain is synchronized, and a low-frequency mechanism that summarizes subsequent systemic conditions from 30ms up to a limit of 3 seconds. Together with the function that provides a certain level of activation, these two functions form the logistical functions of the classification of mental functions. They provide not only the basis of temporal cognition, but also of that which can be subjectively experienced, i.e., of our perceptions (representation or perceptual processing of stimuli), memories (stimulus processing or storage of information), emotions (evaluation of stimuli), and action, respectively reaction (response to stimuli). These four domains are the content-related functions of the classification of mental functions. Objective: The objective of this paper is to determine to what extent empirical data collected from a (neuro-) psychological test battery reflect the representation of the mental functions postulated in theory. The specific goal is the factor-analytical representation of the classification of mental functions according to Pöppel (1993, 1997) by means of the individual tests. Methods: Healthy subjects aged 50 to 65 years without age-associated impairment participated in the pharmacologically-sponsored clinical study. Based on the theory of mental functioning, 15 (neuro-) psychological tests were selected to assess the repertoire of content-related and logistical functions. Nine tests were selected to assess content-related functions and six to assess logistical functions. To further test the dimensionality of Pöppel’s classification, a factor analysis was conducted to indicate to what extent the measuring instruments cover the mental functions in Pöppel’s classification. Results: The content-related function stimulus representation is covered completely, the function action/reaction is covered by variables in two out of three tests. The dimension emotional evaluation of information is largely covered. Temporal reproduction units of <3000ms and 3000ms as essential components of the low-frequency-mechanism of the logistical function temporal organization is distributed in two factors. High-frequency temporal organization of 30ms could not be verified in the present study as well as the function activation/attention. Another factor combines variables of temporal organization and of content implementation. The total variance explained by six factors was 62.1%. Conclusions: The results of the factor-analytical scale replication generally confirm the six given dimensions of the classification. Four of the six mental functions could be represented satisfactorily through factor analysis. Additionally, new aspects of the attribution of the instruments to the theory of mental functions can be assessed. The differentiation becomes most evident within time frames of under and over 3 seconds. The temporal limit of 3 seconds is theoretically assumed to be the threshold between subjective present and the perception of duration. Temporal Organization of 30-40Hz could not be reproduced by factor analysis in the given tests. This time unit is thought to be the threshold between the experience of simultaneity and succession of stimuli. In addition, one dimension comes to the fore that combines the content-related and the logistical components of the brain. The test battery obviously cannot represent some functions in isolation from each other. There may be a dimension on a different level of processing that combines content-related and logistical functions. This event provides evidence for the theoretical assumption of a close connection of content-related and logistical functions. With this study, an important move has been made, to use the classification of mental function for clinical practice. Via selective diagnosis of a deficient function, specific intervention can be implemented. In particular, the logistical functions of the classification have been neglected in neuropsychological practice. An appropriate system of classification is a prerequisite for the scientific exploration of psychological phenomena

The WD40-Protein PfWLP1 Ensures Stability of the PfCCp-Based Adhesion Protein Complex in Plasmodium falciparum Gametocytes

Members of the WD40-repeat protein family can be found in all eukaryotic proteomes where they usually serve as interaction platforms for the assembly of large protein complexes and are therefore essential for the integrity of these complexes. In the malaria parasite Plasmodium falciparum, the WD40-repeat protein PfWLP1 has been shown to interact with members of distinct adhesion protein complexes in the asexual blood stages and gametocyte stages. In this study, we demonstrate that the presence of PfWLP1 is crucial for both the stability of these gametocyte-specific adhesion complexes as well as for gametocyte maturation and gametogenesis. Using reverse genetics, we generated a PfWLP1-knockdown parasite line for functional characterization of the protein. Knockdown of PfWLP1 resulted in a slight reduction of gametocyte numbers and significantly the impaired ability of the gametocytes to exflagellate. PfWLP1-knockdown further led to reduced protein levels of the Limulus coagulation factor C-like (LCCL)-domain proteins PfCCp1 and PfCCp2, which are key components of the adhesion complexes. These findings suggest that the interaction of PfWLP1 with members of the PfCCp-based adhesion complex ensures complex stability and thereby contributes to gametocyte viability and exflagellation

Discovery of palladium, antimony, tellurium, iodine, and xenon isotopes

Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.Comment: to be published in At. Data Nucl. Data Table

Untersuchungen der Photosynthesemembran bei Fichten im Zusammenhang mit den neuartigen Waldschaeden

Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Funktionale Charakterisierung der Patatin-ähnlichen Phospholipase PNPLA1 in den Blut- und Sexualstadien des humanpathogenen Malariaerregers Plasmodium falciparum

The malaria pathogen P. falciparum displays a well-regulated lipid metabolism required to ensure its survival in the human host as well as in the mosquito vector. Therefore, proteins involved in synthesis and acquisition of phospholipids were extensively studied in the past and represent prime targets for malaria therapeutics. In contrast, not much is known about phospholipases, which may have potentially important functions in membrane dynamics, host cell membrane penetration, cell proliferation, and cell signaling due to their phospholipid-hydrolytic activity. In a comprehensive genome analysis carried out within the scope of this work, a total of 22 putative phospholipases were identified in the P. falciparum genome, four of which are annotated as patatin like phospholipases (PNPLA). PNPLA1, a putative PLA2, is present in the asexual and sexual blood stages and here localizes to the cytosol. PNPLA1-deficient parasites showed normal asexual replication, gametocyte development and gametogenesis. However, parasites lacking PNPLA1 formed significantly less gametocyte numbers and showed delayed development of the five maturation stages, while episomal overexpression of PNPLA1 promoted gametocyte formation. The loss of PNPLA1 function also led to a transcriptional deregulation of genes related to game to cytogenesis, including the gene encoding the key regulator of sexual commitment, the transcription factor AP2-G. Comparative lipidodomic analysis of asexual PNPLA1-deficient parasites revealed overall increased levels of major phospholipids, in particular phosphatidylcholine (PC), which is the main component of plasmodial membranes. PC synthesis is known to be pivotal for erythrocytic replication, while reduced availability of PC precursors drives the parasite into game to cytogenesis. Thus, the higher PC levels due to PNPLA1-deficiency might prevent the blood stage parasites from entering the sexual pathway. By the first characterization of a plasmodial PNPLA, the results of this thesis contribute to the elucidation of the biochemical and functional role of phospholipases in the life cycle of the malaria pathogen and deepen the understanding of the sexual differentiation pathway

Phospholipases during membrane dynamics in malaria parasites

Plasmodium parasites, the causative agents of malaria, display a well-regulated lipid metabolism required to ensure their survival in the human host as well as in the mosquito vector. The fine-tuning of lipid metabolic pathways is particularly important for the parasites during the rapid erythrocytic infection cycles, and thus enzymes involved in lipid metabolic processes represent prime targets for malaria chemotherapeutics. While plasmodial enzymes involved in lipid synthesis and acquisition have been studied in the past, to date not much is known about the roles of phospholipases for proliferation and transmission of the malaria parasite. These phospholipid-hydrolyzing esterases are crucial for membrane dynamics during host cell infection and egress by the parasite as well as for replication and cell signaling, and thus they are considered important virulence factors. In this review, we provide a comprehensive bioinformatic analysis of plasmodial phospholipases identified to date. We further summarize previous findings on the lipid metabolism of Plasmodium, highlight the roles of phospholipases during parasite life-cycle progression, and discuss the plasmodial phospholipases as potential targets for malaria therapy