Does cholesterol act as a protector of cholinergic projections in Alzheimer's disease?

The relationship between Alzheimer's disease (AD) and progressive degeneration of the forebrain cholinergic system is very well established, whereas mechanisms linking this disease with cholesterol, apolipoprotein E (apoE) phenotype, and amyloid precursor protein (APP) metabolism have not been fully elucidated even though there is a plethora of publications separately on each of these issues. The intention of this hypothesis is to unify knowledge coming from all of these areas. It is based on an assumption that the process of APP hypermetabolism is a neuroprotective response for age-related cholinergic deterioration. In some individuals this initially positive process becomes highly overregulated by genetic or/and epigenetic risk factors and after many years of accumulations lead eventually to AD. I hypothesise that neuroprotective role of APP-hypermetabolism might be related to enrichment of neuronal membranes (lipid rafts in particular) in cholesterol in order to compensate for decrease in presynaptic cholinergic transmission and/or AD-related decrease in cholesterol levels. The above is consistent with findings indicating that activity of both muscarinic and nicotinic cholinergic receptors is correlated in a positive manner with cholesterol plasmalemmal content. Briefly – APP metabolism together with transport of cholesterol in apoE containing lipoproteins seem to play a key role in mobilising cholesterol into neuronal membranes

Astronauci amerykańscy w Toruniu w 1972 roku. „Utajniona wizyta”

Der Beitrag beschreibt den Besuch von zwei Astronauten der Apollo-15-Mission in Thorn, D. Scott und A. Worden (am 19. Januar 1972). Er fand unter ungewöhnlichen Umständen statt, mit einem herabgesetzten diplomatischen Status und unter beträchtlichen Einschränkungen bei der Berichterstattung. Der Verlauf des Besuchs wurde hauptsächlich anhand von Unterlagen des polnischen Staatssicherheitsdienstes rekonstruiert. Mit Hilfe der polnischen diplomatischen Dokumente wurden Gründe für die von den staatlichen Behörden verhängte Informationssperre dargelegt. Besondere Aufmerksamkeit wurde der Begrüßungsansprache des Rektors der Thoruner Universität Witold Łukaszewicz gewidmet (im Aktenbestand des Staatssicherheitsdienstes erhalten; vollständig dem Beitrag beigefügt).The article describes the visit of two astronauts of the Apollo 15 mission in Toruń, D. Scott and A. Worden (19 January 1972). It took place in unusual circumstances, with a lowered diplomatic status and severe restrictionson providing information about it. The course of the visit was reconstructed mainly using the Polish Security Service (Służba Bezpieczeństwa) documents. The Polish Diplomatic Documents helped to explain the reasons for the information blockade applied by the state authorities. Particular attention was paid to the welcome speech of Rector Witold Łukaszewicz (preserved in the files of the Security Service; attached in its entirety to the article).W artykule opisano wizytę Davida Scotta i Alfreda Wordena –dwóch astronautów misji Apollo 15 w Toruniu, 19 stycznia 1972 r. – wydarzenie jak dotychczas słabo znane. Odbyła się ona w niezwykłych okolicznościach, przy obniżonym statusie dyplomatycznym i dużych ograniczeniach w podawaniu informacji o nim w mediach. Rekonstrukcji przebiegu wizyty dokonano głównie na podstawie dokumentów SB. Za pomocą akt opublikowanych w Polskich Dokumentach Dyplomatycznych wyjaśniono zaś przyczyny niskiego statusu wizyty. Szczególną uwagę poświęcono opisowi uroczystości powitalnej oraz spontanicznych reakcji mieszkańców Torunia na obecność gości podczas ich spaceru po starówce. Załączono również krótki biogram rektora Jerzego Łukaszewicza i tekst mowy powitalnej (w zasobach SB) wygłoszonej przez niego oraz komentarz do tego dokumentu

Resting-State Functional Connectivity in Late-Life Depression: Higher Global Connectivity and More Long Distance Connections

Functional magnetic resonance imaging recordings in the resting-state (RS) from the human brain are characterized by spontaneous low-frequency fluctuations in the blood oxygenation level dependent signal that reveal functional connectivity (FC) via their spatial synchronicity. This RS study applied network analysis to compare FC between late-life depression (LLD) patients and control subjects. Raw cross-correlation matrices (CM) for LLD were characterized by higher FC. We analyzed the small-world (SW) and modular organization of these networks consisting of 110 nodes each as well as the connectivity patterns of individual nodes of the basal ganglia. Topological network measures showed no significant differences between groups. The composition of top hubs was similar between LLD and control subjects, however in the LLD group posterior medial-parietal regions were more highly connected compared to controls. In LLD, a number of brain regions showed connections with more distant neighbors leading to an increase of the average Euclidean distance between connected regions compared to controls. In addition, right caudate nucleus connectivity was more diffuse in LLD. In summary, LLD was associated with overall increased FC strength and changes in the average distance between connected nodes, but did not lead to global changes in SW or modular organization

Viewing 3D TV over two months produces no discernible effects on balance, coordination or eyesight

With the rise in stereoscopic 3D media, there has been concern that viewing stereoscopic 3D (S3D) content could have long-term adverse effects, but little data are available. In the first study to address this, 28 households who did not currently own a 3D TV were given a new TV set, either S3D or 2D. The 116 members of these households all underwent tests of balance, coordination and eyesight, both before they received their new TV set, and after they had owned it for 2 months. We did not detect any changes which appeared to be associated with viewing 3D TV. We conclude that viewing 3D TV does not produce detectable effects on balance, coordination or eyesight over the timescale studied. Practitioner Summary: Concern has been expressed over possible long-term effects of stereoscopic 3D (S3D). We looked for any changes in vision, balance and coordination associated with normal home S3D TV viewing in the 2 months after first acquiring a 3D TV. We find no evidence of any changes over this timescale

Compensatory weight gain due to dopaminergic hypofunction: new evidence and own incidental observations

There is increasing evidence for a role of dopamine in the development of obesity. More specifically, dopaminergic hypofunction might lead to (over)compensatory food intake. Overeating and resulting weight gain may be induced by genetic predisposition for lower dopaminergic activity, but might also be a behavioral mechanism of compensating for decreased dopamine signaling after dopaminergic overstimulation, for example after smoking cessation or overconsumption of high palatable food. This hypothesis is in line with our incidental finding of increased weight gain after discontinuation of pharmaceutical dopaminergic overstimulation in rats. These findings support the crucial role of dopaminergic signaling for eating behaviors and offer an explanation for weight-gain after cessation of activities associated with high dopaminergic signaling. They further support the possibility that dopaminergic medication could be used to moderate food intake

Compensatory weight gain due to dopaminergic hypofunction: new evidence and own incidental observations

There is increasing evidence for a role of dopamine in the development of obesity. More specifically, dopaminergic hypofunction might lead to (over)compensatory food intake. Overeating and resulting weight gain may be induced by genetic predisposition for lower dopaminergic activity, but might also be a behavioral mechanism of compensating for decreased dopamine signaling after dopaminergic overstimulation, for example after smoking cessation or overconsumption of high palatable food. This hypothesis is in line with our incidental finding of increased weight gain after discontinuation of pharmaceutical dopaminergic overstimulation in rats. These findings support the crucial role of dopaminergic signaling for eating behaviors and offer an explanation for weight-gain after cessation of activities associated with high dopaminergic signaling. They further support the possibility that dopaminergic medication could be used to moderate food intake

Stereoacuity with Frisby and revised FD2 stereo tests.

We compared near stereoacuity, measured with the Frisby test, and distance stereoacuity, measured with the revised Frisby-Davis (FD2) test, enabling a comparison with the original version of the FD2. In the revised version of the FD2 test, a white background is used instead of a backlit background. We also examined the effect of age, gender and visual problems. We used the Frisby test at distances ranging from 30-80 cm and FD2 at 6 m. The best possible score was 20 seconds of arc (arcsec) on the Frisby and 5 arcsec on the FD2; participants who could not perform a test despite demonstrating understanding of it were classed as stereonegative. We examined both the whole population recruited, and a sub-population screened so as to exclude visual problems. We analysed our results in three age-groups: "visually developing" (36 children aged 5-10 years); "visually mature" (300 participants aged 11-49 years) and "older" (29 participants aged 50-82). In the whole population, the median stereoacuity on the Frisby test was 25, 20 and 85 arcsec in the three age-groups. In the sub-population with no visual problems, median Frisby stereoacuity was similar at 20, 20 and 80 arcsec respectively. On the FD2, the medians were 10, 10, 20 arcsec for the whole population and 7.5, 10 and 12.5 for the sub-population. Children were more likely than adults to be stereonegative on the FD2, although none of the children were stereonegative on the Frisby. The two tests showed fair agreement when used to classify people into three categories of stereovision. Poor stereovision was often associated with binocular problems such as tropia, but with many exceptions. In line with previous studies, we found improvements in measured stereoacuity in childhood and declines in late adulthood. The new FD2 test gives comparable values to the original FD2