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Introduction To date, most ways to perform facial expression recognition rely on two-dimensional images, advanced approaches with three-dimensional data exist. These however demand stationary apparatuses and thus lack portability and possibilities to scale deployment. As human emotions, intent and even diseases may condense in distinct facial expressions or changes therein, the need for a portable yet capable solution is signified. Due to the superior informative value of three-dimensional data on facial morphology and because certain syndromes find expression in specific facial dysmorphisms, a solution should allow portable acquisition of true three-dimensional facial scans in real time. In this study we present a novel solution for the three-dimensional acquisition of facial geometry data and the recognition of facial expressions from it. The new technology presented here only requires the use of a smartphone or tablet with an integrated TrueDepth camera and enables real-time acquisition of the geometry and its categorization into distinct facial expressions. Material and Methods Our approach consisted of two parts: First, training data was acquired by asking a collective of 226 medical students to adopt defined facial expressions while their current facial morphology was captured by our specially developed app running on iPads, placed in front of the students. In total, the list of the facial expressions to be shown by the participants consisted of “disappointed”, “stressed”, “happy”, “sad” and “surprised”. Second, the data were used to train a self-normalizing neural network. A set of all factors describing the current facial expression at a time is referred to as “snapshot”. Results In total, over half a million snapshots were recorded in the study. Ultimately, the network achieved an overall accuracy of 80.54% after 400 epochs of training. In test, an overall accuracy of 81.15% was determined. Recall values differed by the category of a snapshot and ranged from 74.79% for “stressed” to 87.61% for “happy”. Precision showed similar results, whereas “sad” achieved the lowest value at 77.48% and “surprised” the highest at 86.87%. Conclusions With the present work it can be demonstrated that respectable results can be achieved even when using data sets with some challenges. Through various measures, already incorporated into an optimized version of our app, it is to be expected that the training results can be significantly improved and made more precise in the future. Currently a follow-up study with the new version of our app that encompasses the suggested alterations and adaptions, is being conducted. We aim to build a large and open database of facial scans not only for facial expression recognition but to perform disease recognition and to monitor diseases’ treatment progresses.

Background: Previous studies have suggested an increased prevalence of congenital heart disease among children born to women aged ≥35 years. In recent decades, the mother’s age at childbirth has increased dramatically in industrialized countries. It has not been investigated if increasing maternal age affects the neonatal cardiac electrical system. Methods: The Copenhagen Baby Heart Study is a prospective general population study that performed cardiac evaluation in newborns. Electrocardiograms were analyzed with a computerized algorithm. Results: We included 16,518 newborns with normal echocardiograms (median age 11 days; range 0–30 days; 52% boys). Median maternal age at delivery was 31 years; 790 newborns were born to mothers aged between 16 and 24 years, 11,403 between 25 and 34 years, 4,279 between 35 and 44 years, and 46 newborns had mothers aged between 45 and 54 years. The QRS axis and maximum R-wave amplitude in V1 (R-V1) differed across the four maternal age groups (both p < 0.01), with absolute differences of 3.5% (114 vs. 110°) and 12% (1,152 vs. 1,015 µV), respectively, between newborns with the youngest and oldest mothers. Associations between maternal age and the QRS axis and R-V1 remained significant after multifactorial adjustment. Heart rate, PR interval, QRS duration, uncorrected QT interval, QTcBazett, and maximum amplitudes of S-V1, R-V6, and S-V6 were not associated with maternal age (all p > 0.05). Conclusion: We observed a significant association between maternal age and the neonatal QRS axis and R-V1. However, the absolute differences were relatively small and maternal age is unlikely to have a clinically significant effect on the neonatal cardiac electrical system.

OBJECTIVES Interpretation of the neonatal electrocardiogram (ECG) is challenging due to the profound changes of the cardiovascular system in this period. We aimed to investigate the impact of gestational age (GA) on the neonatal ECG and create GA-specific reference values. METHODS The Copenhagen Baby Heart Study is a prospective general population study that offered cardiac evaluation of neonates. ECGs and echocardiograms were obtained and systematically analyzed. GA, weight, height, and other baseline variables were registered. RESULTS We included 16 462 neonates (52% boys) with normal echocardiograms. The median postnatal age was 11 days (range 0 to 30), and the median GA was 281 days (range 238 to 301). Analyzing the ECG parameters as a function of GA, we found an effect of GA on almost all investigated ECG parameters. The largest percentual effect of GA was on heart rate (HR; 147 vs 139 beats per minute), the QRS axis (103° vs 116°), and maximum R-wave amplitude in V1 (R-V1; 0.97 vs 1.19 mV) for GA ≤35 vs ≥42 weeks, respectively. Boys had longer PR and QRS intervals and a more right-shifted QRS axis within multiple GA intervals (all P < .01). The effect of GA generally persisted after multifactorial adjustment. CONCLUSIONS GA was associated with significant differences in multiple neonatal ECG parameters. The association generally persisted after multifactorial adjustment, indicating a direct effect of GA on the developing neonatal cardiac conduction system. For HR, the QRS axis, and R-V1, the use of GA-specific reference values may optimize clinical handling of neonates.

Objective: The interpretation of the neonatal electrocardiogram (ECG) is challenging and reflects the underlying developing physiology. The possible effects of gestational age (GA) on the ECG has never been evaluated in a large general population study. We aimed at investigating the effect of GA on neonatal electrocardiographic parameters and create GA-specific reference values. Methods: The Copenhagen Baby Heart Study is a prospective, general population study that offered cardiac evaluation of neonates. ECGs and echocardiograms were obtained and systematically analyzed. GA, weight, height, and other baseline variables were registered. Results: We included 16,462 neonates (52% boys) with normal echocardiograms. Median postnatal age was 11 days (range 0-30 days) and median GA was 281 days (range 238-301 days). Analyzing the ECG parameters as a function of GA we found a significant effect of GA on heart rate (HR), PR-, QRS-, and QT intervals, QRS axis, and maximum amplitudes of R-waves in V1/V6 and maximum S-wave in V6 (all pBox plots of ECG parameters subdivided by gestational age intervals and sex ). The effect of GA generally persisted after adjustment for HR, weight, postnatal age, and sex. In addition, when comparing HR, PR interval, QRS axis, QRS duration, uncorrected QT interval, and QTcBazett subdivided into postnatal age intervals, we found a significant effect of gestational age on most ECG parameters within these postnatal age intervals. Conclusion: Gestational age was associated with significant differences in multiple neonatal ECG parameters and the effect generally persisted after multifactorial adjustment. Our results indicate a direct effect of GA on the developing neonatal cardiac conduction system. Use of GA-specific reference values may be useful.

Zusammenfassung Hintergrund Wartezeiten auf die Aufnahme in eine psychosomatische Klinik verhindern die akut notwendige Behandlung und können zu verlängerter Arbeitsunfähigkeit und weiterer Chronifizierung führen. Von den meisten psychosomatischen Kliniken werden Wartezeiten berichtet, es existieren bisher jedoch keine Studien und verlässlichen Daten hierzu. Daher war es das Ziel dieser Studie, in einer definierten Region prospektiv zu untersuchen, wie lange es bis zu einem ambulanten Vorgespräch und bis zur Klinikaufnahme dauert. Weiter sollte geprüft werden, ob es externe Faktoren gibt, die diese Dauern beeinflussen. Methode 7 Kliniken aus der Region Süd-Württemberg nahmen an dieser Untersuchung teil, 2 davon betreiben größere Tagesklinken. Die Daten wurden 2015 über 9 Monate prospektiv erhoben, insgesamt wurden 916 Aufnahmen erfasst. Erfasst wurde die Wartezeit bis zu einem Vorgespräch, in dem die Indikation geprüft wurde, und die Zeit bis zur tatsächlichen Aufnahme in die Klinik. Ergebnisse Die Wartezeit bis zum ambulanten Vorgespräch betrug im Mittel 25 Tage (SD=31), bis zur Aufnahme nach dem Vorgespräch 56 Tage (SD=47). Insgesamt dauerte es vom Erstkontakt bis zur Aufnahme im Mittel demnach mehr als 10 Wochen. Patienten, die auf einen Tagesklinikplatz warteten, mussten noch länger warten. Ein Dringlichkeitsvermerk durch den Therapeuten des Vorgesprächs sowie eine private Krankenversicherung führten zu etwas kürzeren Wartezeiten. Die Diagnosegruppe hatte keinen Einfluss auf die Wartezeit. Schlussfolgerungen Die Wartezeiten sind beträchtlich und belasten den Patienten, aber auch das Gesundheitssystem. Es wäre wünschenswert, wenn solche Wartezeiten systematisch erhoben und veröffentlicht würden. Die Politik, aber auch die Handelnden im Gesundheitswesen sollten in einem Gesprächsprozess klären, ob und wie dieser Missstand verändert werden kann.

Waiting times for the admission into a so called psychosomatic hospital in Germany prevent the necessary immediate treatment. They lead to further incapacity for work and chronic manifestation of the disease. It is reported that most psychosomatic hospitals have waiting times, but there are no studies on data on that. Therefore, it was the aim of this study to access prospectively in a defined region, how long it takes for the patients to get an outpatient preliminary talk and thereafter, how long they have to wait for their admission.7 hospitals out of the region of South-Württemberg took part on this study, 2 of them had bigger day hospitals. Data were assessed prospectively in 2015 over 9 months, in total 916 admissions were assessed.The waiting time until a preliminary talk, in which the indication for inpatient treatment was secured, was in the mean 25 days (SD=31). The waiting time after this talk until admission was 56 days (SD=47). Patients who waited for a day treatment had to wait even longer. An urgency remark, given by the therapist of the preliminary talk, as well as a private illness insurance led to shorter waiting times. The diagnosis had no influence on the waiting time.The waiting times are substantial and imply a burden for the patient and also for the health care system. It is recommended to assess and publish these waiting times on a regularly basis. Politics, but also the actors in the health care system should discuss if and how this deficit can be changed.Wartezeiten auf die Aufnahme in eine psychosomatische Klinik verhindern die akut notwendige Behandlung und können zu verlängerter Arbeitsunfähigkeit und weiterer Chronifizierung führen. Von den meisten psychosomatischen Kliniken werden Wartezeiten berichtet, es existieren bisher jedoch keine Studien und verlässlichen Daten hierzu. Daher war es das Ziel dieser Studie, in einer definierten Region prospektiv zu untersuchen, wie lange es bis zu einem ambulanten Vorgespräch und bis zur Klinikaufnahme dauert. Weiter sollte geprüft werden, ob es externe Faktoren gibt, die diese Dauern beeinflussen.7 Kliniken aus der Region Süd-Württemberg nahmen an dieser Untersuchung teil, 2 davon betreiben größere Tagesklinken. Die Daten wurden 2015 über 9 Monate prospektiv erhoben, insgesamt wurden 916 Aufnahmen erfasst. Erfasst wurde die Wartezeit bis zu einem Vorgespräch, in dem die Indikation geprüft wurde, und die Zeit bis zur tatsächlichen Aufnahme in die Klinik.Die Wartezeit bis zum ambulanten Vorgespräch betrug im Mittel 25 Tage (SD=31), bis zur Aufnahme nach dem Vorgespräch 56 Tage (SD=47). Insgesamt dauerte es vom Erstkontakt bis zur Aufnahme im Mittel demnach mehr als 10 Wochen. Patienten, die auf einen Tagesklinikplatz warteten, mussten noch länger warten. Ein Dringlichkeitsvermerk durch den Therapeuten des Vorgesprächs sowie eine private Krankenversicherung führten zu etwas kürzeren Wartezeiten. Die Diagnosegruppe hatte keinen Einfluss auf die Wartezeit.Die Wartezeiten sind beträchtlich und belasten den Patienten, aber auch das Gesundheitssystem. Es wäre wünschenswert, wenn solche Wartezeiten systematisch erhoben und veröffentlicht würden. Die Politik, aber auch die Handelnden im Gesundheitswesen sollten in einem Gesprächsprozess klären, ob und wie dieser Missstand verändert werden kann.

Neuroprotective properties of bilobalide, a specific constituent of Ginkgo extracts, were tested in a mouse model of stroke. After 24 hours of middle cerebral artery occlusion (MCAO), bilobalide reduced infarct areas in the core region (striatum) by 40-50% when given at 10 mg/kg one hour prior to MCAO. Neuroprotection was also observed at lower doses, or when the drug was given 1 h past stroke induction. Sensorimotor function in mice was improved by bilobalide as shown by corner and chimney tests. When brain metabolism in situ was monitored by microdialysis, MCAO caused a rapid disappearance of extracellular glucose in the striatum which returned to baseline levels after reperfusion. Extracellular levels of glutamate were increased by more than ten-fold in striatal tissue, and by four- to fivefold in hippocampal tissue (penumbra). Bilobalide did not affect glucose levels but strongly attenuated glutamate release in both core and penumbra regions. Bilobalide was equally active when given locally via the microdialysis probe and also reduced ischemia-induced glutamate release in vitro in brain slices. We conclude that bilobalide is a strong neuroprotectant in vivo at doses that can be used therapeutically in humans. The mechanism of action evidently involves reduction of glutamate release, thereby reducing excitotoxicity.

Alzheimer's disease is characterized by amyloid peptide formation and deposition, neurofibrillary tangles, synaptic loss and central cholinergic dysfunction, dysfunction of energy metabolism, and dementia; however, the interactions between these hallmarks remain poorly defined. We studied a well characterized mouse model of amyloid deposition, the doubly transgenic APP(SWE)xPSEN1dE9 mouse. At 10 to 14 months of age, these mice had high levels of amyloid peptides (6.6 microg/g wet weight) and widespread amyloid plaques. Extracellular levels of acetylcholine (ACh) were determined by microdialysis in the hippocampus and were comparable with nontransgenic mice from the same colony. In the open field, both mouse strains responded with a 3-fold increase of hippocampal ACh release. Exploratory behavior of the transgenic mice appeared normal. Infusion of scopolamine evoked 5- to 6-fold increases of ACh levels in both mouse strains. High-affinity choline uptake and cholinesterase activities were identical in both mouse lines. Extracellular levels of glucose and glycerol were similar in control and transgenic mice, whereas lactate levels were slightly (p = 0.06) and glutamate levels significantly (p = 0.02) lower in transgenic mice. Exploration caused increases of glucose and lactate, whereas infusion of scopolamine (1 microM) increased glucose but not lactate. Glutamate levels were increased by scopolamine, whereas glycerol remained constant under all the conditions. We conclude that amyloid peptide production and plaque deposition causes minor changes in cholinergic function and energy metabolites in transgenic mice in vivo. Amyloid peptide formation and/or deposition may not be sufficient for long-term cholinergic or metabolic dysfunction.

Mice deficient for acetylcholinesterase (AChE) have strongly increased extracellular levels of acetylcholine (ACh) in the dorsal hippocampus [Hartmann, J., Kiewert, C., Duysen, E.G., Lockridge, O., Greig, N.H., Klein, J., 2007. Excessive hippocampal acetylcholine levels in acetylcholinesterase-deficient mice are moderated by butyrylcholinesterase activity. J. Neurochem. 100, 1421-1429]. Using microdialysis, we found that increased ACh levels are accompanied by decreased levels of extracellular choline which were 1.60 microM in AChE-deficient mice and 4.36 microM in wild-type mice. Addition of choline (10 microM) to the perfusion fluid, while ineffective in wild-type animals, more than doubled extracellular ACh levels in AChE-deficient mice. High-affinity choline uptake (HACU), as measured ex vivo in corticohippocampal synaptosomes, was more than doubled in AChE-deficient mice. Inhibition of HACU by hemicholinium-3 (HC-3) in vivo reduced extracellular levels of ACh by 60% in wild-type mice but by more than 90% in AChE-deficient mice. Decreased ACh levels caused by infusion of HC-3 or tetrodotoxin (TTX) were accompanied by increased levels of free choline. Infusion of scopolamine (1 microM) caused a fivefold increase of ACh levels in wild-type animals but only a 50% increase in AChE-deficient mice. In conclusion, absence of AChE causes dynamic changes in the ratio of choline to ACh. High levels of extracellular ACh are accompanied by reduced levels of extracellular choline, and ACh release becomes strongly dependent on choline availability. Similar changes may take place in patients chronically exposed to AChE inhibitors.

Bilobalide, a constituent of Ginkgo biloba , has neuroprotective properties. Its mechanism of action is unknown but it was recently found to interact with neuronal transmission mediated by glutamate, γ-aminobutyric acid (GABA) and glycine. The goal of this study was to test the interaction of bilobalide with glycine in assays of neuroprotection. In rat hippocampal slices exposed to N -methyl- d -aspartate (NMDA), release of choline indicates breakdown of membrane phospholipids. NMDA-induced choline release was almost completely blocked in the presence of bilobalide (10 µM). Glycine (10–100 µM) antagonized the inhibitory action of bilobalide in this assay. In a second assay of excitotoxicity, we measured tissue water content as an indicator of cytotoxic edema formation in hippocampal slices which were exposed to NMDA. In this assay, edema formation was suppressed by bilobalide but bilobalide's action was attenuated in the presence of glycine and of d -serine (100 µM each). To investigate bilobalide's interaction with glycine receptors directly, we determined 36 chloride flux in rat cortico-hippocampal synaptoneurosomes. Glycine (100 µM) was inactive in this assay indicating an absence of functional glycine-A receptors in this preparation. [ 3 H]Glycine was used to assess binding at the glycine binding site of the NMDA receptor but bilobalide was found to be inactive in this assay. Finally, [ 3 H]glycine release was monitored in hippocampal slices exposed to oxygen-glucose deprivation. In this model, glycine release was induced by ischemia, an effect that was strongly reduced by bilobalide. We conclude that bilobalide does not interact with glycine receptors in neurochemical assays but it significantly reduces the release of glycine under ischemic conditions. This effect likely contributes to bilobalide's neuroprotective effects in assays of excitotoxicity and ischemia.

Bilobalide, a constituent of Ginkgo biloba, has neuroprotective properties. Its mechanism of action is unknown but it was recently found to block GABA(A) receptors. The goal of this study was to test the potential role of a GABAergic mechanism for the neuroprotective activity of bilobalide. In rat hippocampal slices exposed to NMDA, release of choline indicates breakdown of membrane phospholipids. NMDA-induced choline release was almost completely blocked in the presence of bilobalide (10 microM) and under low-chloride conditions. Bicuculline (100 microM), a competitive antagonist at GABA(A) receptors, reduced NMDA-induced choline release to a small extent (-23%). GABA (100 microM) partially antagonized the inhibitory action of bilobalide. Exposure of hippocampal slices to NMDA also caused edema formation as measured by increases of tissue water content. NMDA-induced edema formation was suppressed by bilobalide and by low-chloride conditions. Bicuculline exerted partial protection (by 30%) while GABA reduced bilobalide's effect by about one third. To investigate bilobalide's interaction with GABA(A) receptors directly, we measured binding of [(35)S]-TBPS to rat cortical membranes. TBPS binding was competitively inhibited by bilobalide in the low micromolar range (IC(50)=3.7 microM). As a functional test, we determined (36)chloride flux in rat corticohippocampal synaptoneurosomes. GABA (100 microM) significantly increased (36)chloride flux (+65%), and this increase was blocked by bilobalide, but with low potency (IC(50): 39 microM). We conclude that, while antagonism of GABA(A) receptors may contribute to bilobalide's neuroprotective effects, additional mechanisms must be postulated to fully explain bilobalide's actions.

Central cholinergic systems are involved in a plethora of brain functions and are severely and selectively damaged in neurodegenerative diseases such as Alzheimer’s disease and dementia with Lewy bodies. Cholinergic dysfunction is treated with inhibitors of acetylcholinesterase (AChE) while the role of butyrylcholinesterase (BChE) for brain cholinergic function is unclear. We have used in vivo microdialysis to investigate the regulation of hippocampal acetylcholine (ACh) levels in mice that are devoid of AChE (AChE-/- mice). Extracellular ACh levels in the hippocampus were 60-fold elevated in AChE-/- mice compared with wild-type (AChE+/+) animals. In AChE-/- mice, calcium-free conditions reduced hippocampal ACh levels by 50%, and infusion of tetrodotoxin by more than 90%, indicating continuous ACh release. Infusion of a selective AChE inhibitor (BW284c51) caused a dose-dependent, up to 16-fold increase of extracellular ACh levels in AChE+/+ mice but did not change ACh levels in AChE-/- mice. In contrast, infusion of a selective inhibitor of BChE (bambuterol) caused up to fivefold elevation of ACh levels in AChE-/- mice, but was without effect in AChE+/+ animals. These results were corroborated with two other specific inhibitors of AChE and BChE, tolserine and bis-norcymserine, respectively. We conclude that lack of AChE causes dramatically increased levels of extracellular ACh in the brain. Importantly, in the absence of AChE, the levels of extracellular ACh in the brain are controlled by the activity of BChE. These results point to a potential usefulness of BChE inhibitors in the treatment of central cholinergic dysfunction in which brain AChE activity is typically reduced.

Extracts of the medicinal plant St. John’s Wort ( Hypericum perforatum ) are widely used in the therapy of affective disorders and have been reported to exert antidepressant, anxiolytic, and cognitive effects in experimental and clinical studies. We here report that hyperforin, the major active constituent of the extract, increases the release of acetylcholine from rat hippocampus in vivo as determined by microdialysis. Hippocampal acetylcholine levels were increased by 50–100% following the systemic administration of pure hyperforin at doses of 1 and 10 mg/kg. The effect was almost completely suppressed by local perfusion with calcium-free buffer or with tetrodotoxin (1 μM). We conclude that hyperforin releases hippocampal acetylcholine by an indirect mechanism of action which is calcium-dependent and requires intact neuronal communication and cell firing. Our findings suggest therapeutic efficacy of St. John’s Wort extracts in central cholinergic dysfunction.

The cholinergic inputs to the rat hippocampus were lesioned by intraseptal injections of 192 IgG-saporin. After 15 days, fetal septal cells were grafted into the hippocampus. Thirteen months later, hippocampal acetylcholine (ACh) release was studied by microdialysis. Lesioning reduced basal ACh release (100%) to 20% of normal, which was compensated for by the graft (71%). Infusion of the serotonin uptake inhibitor citalopram (100 μM) enhanced ACh release to the same extent (% of basal release) in all rat groups. Systemic injection of 8-OH-DPAT (0.5 mg/kg, SC), an agonist of 5-HT1A receptors, caused a smaller ACh release than citalopram. Acetylcholinesterase (AChE) staining and densitometric quantification revealed that the lesion-induced reduction of the AChE-staining density was compensated for by septal grafting. In conclusion, both histochemical and biochemical methods showed that cholinergic hippocampal parameters were drastically impaired by 192 IgG-saporin lesions, but were almost completely restored by septal grafting. The graft responded to intrinsic serotonergic regulation.

In the biosynthesis of the antiarrhythmic alkaloid ajmaline, polyneuridine aldehyde esterase (PNAE) catalyses a central reaction by transforming polyneuridine aldehyde into epi-vellosimine, which is the immediate precursor for the synthesis of the ajmalane skeleton. The PNAE cDNA was previously heterologously expressed in E. coli. Sequence alignments indicated that PNAE has a 43% identity to a hydroxynitrile lyase from Hevea brasiliensis, which is a member of the α/β hydrolase superfamily. The catalytic triad, which is typical for this family, is conserved. By site-directed mutagenesis, the members of the catalytic triad were identified. For further detection of the active residues, a model of PNAE was constructed based on the X-ray crystallographic structure of hydroxynitrile lyase. The potential active site residues were selected on this model, and were mutated in order to better understand the relationship of PNAE with the α/β hydrolases, and as well its mechanism of action. The results showed that PNAE is a novel member of the α/β hydrolase enzyme superfamily.

It is often stated that AND/EXOR circuits are much easier to test than AND/OR circuits. This statement, however, only holds true for circuits derived from restricted classes of AND/EXOR expressions, like positive polarity Reed-Muller and fixed polarity Reed-Muller expressions. For these two classes of expressions, circuits with good deterministic testability properties are known. In this paper we show that these circuits also have good random pattern testability attributes. An input probability distribution is given that yields a short expected test length for biased random patterns. This is the first time theoretical results on random pattern testability are presented for 2-level AND/EXOR circuit realizations of arbitrary Boolean functions. It turns out that analogous results cannot be expected for less restricted classes of 2-level AND/EXOR circuits. We present experiments demonstrating that generally minimized 2-level AND/OR circuits can be tested as easy (or hard) as minimized 2-level AND/EXOR circuits.

The bridged aniline or 1-naphthylamine derivatives 8–10 react with nitrous acid in the presence of perchloric acid to give the bridged diphenoquinone diiminium salts 12·2 HClO4, 17·2 HClO4, 19·2 HClO4 and 23. The same products are obtained from these substrates upon their reaction with hydrogen peroxide. Upon treatment of the bridged diphenoquinone diiminium salts 12·2 HClO4 and 23 with base, a disproportionation reaction occurs resulting in the formation of the corresponding benzidine derivatives 13 and 26 and, following a multistep process, the quinoline derivatives 15 and 25 are obtained. Analogously, the 1,2-dihydrobenzo[c,d]indole hydroperchlorate 10·HClO4 is transformed into the bridged benzidine derivative 21 and the bis(benzo[c,d]indol-6-yl) hydroperchlorate 20·HClO4. Furthermore, as a result of an oxidation process initiated by the protonated species of the corresponding indaminium salts, condensation of N,N-dimethyl-4-nitrosoaniline (27) with the bridged aniline or naphthylamine derivatives 8a–8c leads to the N′-(6-quinolyl)-substituted N,N-dimethylbenzoquinone bis(iminium) salts 29a–28c rather than the corresponding indaminium salts 28a–28c.

By nitrosation of the mineralic acid salts of N-monosubstituted 1-naphthylamines (7) N-monosubstituted N′-hydroxy-naphthoquinone diiminium salts (9) are formed. These compounds can condense with their naphthylamine educts 7 to deeply colored N-(4-amino-naphthyl)-substituted naphthoquinone diiminium salts 11 which are available by the reaction of the mineralic acid salts of N-monosubstituted 1-naphthylamines 7 with one half equivalent of nitrous acid in acetic acid solution also. The new indaminium salts 11 absorb, in contrast to their deprotonated species 12 which exhibit intense absorption bands at about 550 nm, in the near infrared region very intensively at about 820 nm.

Middle cerebral artery occlusion (MCAO) is a popular model in experimental stroke research and causes prominent ischemic damage in the forebrain. To characterize metabolic changes induced by MCAO, we have induced permanent MCAO in mice that were implanted with a microdialysis probe in either striatum or hippocampus. Immediately after the onset of ischemia, glucose levels dropped to

Purpose. Alzheimer´s disease is characterized by a dysfunction of central cholinergic systems and is treated by inhibitors of acetylcholinesterase (AChE). This study tests the effect of two AChE inhibitors in therapeutic use, rivastigmine and donepezil, in mice that are devoid of AChE (AChE-/- mice). Rivastigmine is an inhibitor of both AChE and butyrylcholinesterase (BChE) whereas donepezil is a selective inhibitor of AChE. Methods. We have used in vivo microdialysis to investigate the effects of the two drugs on the extracellular concentration of acetylcholine (ACh) in the hippocampus of AChE-/- mice. Results. Extracellular ACh levels in the hippocampus were 30-fold elevated in AChE-/- mice compared to wild-type (AChE+/+) animals. Infusion of rivastigmine (1 and 10 µM) caused a further doubling of ACh levels in AChE-/- mice within 90-120 min. In contrast, infusion of donepezil (1 µM) did not affect hippocampal ACh levels in AChE-/- mice although it increased ACh levels more than twofold in wild-type mice. Conclusions. In the absence of AChE, rivastigmine enhances the levels of extracellular ACh by inhibiting BChE. This finding may be of therapeutic relevance because BChE activity is preserved, but AChE activity is strongly decreased, in late-stage Alzheimer´s disease.

Kearns-Sayre syndrome has been associated with large heteroplasmic mitochondrial DNA deletions and morphological alterations at the cytological level. We have measured the activities of different respiratory chain complexes in 3 patients presenting mitochondrial DNA deletions and found no close correlation between gene deletions and enzymatic activities. These data, therefore, point out the importance of analyses at the mitochondrial DNA level in such mitochondrial disorders because gross biochemistry may miss any defect.

Central cholinergic systems are involved in a plethora of brain functions and are severely and selectively damaged in neurodegenerative diseases such as Alzheimer's disease and dementia with Lewy bodies. Cholinergic dysfunction is treated with inhibitors of acetylcholinesterase (AChE) while the role of butyrylcholinesterase (BChE) for brain cholinergic function is unclear. We have used in vivo microdialysis to investigate the regulation of hippocampal acetylcholine (ACh) levels in mice that are devoid of AChE (AChE-/- mice). Extracellular ACh levels in the hippocampus were 60-fold elevated in AChE-/- mice compared with wild-type (AChE+/+) animals. In AChE-/- mice, calcium-free conditions reduced hippocampal ACh levels by 50%, and infusion of tetrodotoxin by more than 90%, indicating continuous ACh release. Infusion of a selective AChE inhibitor (BW284c51) caused a dose-dependent, up to 16-fold increase of extracellular ACh levels in AChE+/+ mice but did not change ACh levels in AChE-/- mice. In contrast, infusion of a selective inhibitor of BChE (bambuterol) caused up to fivefold elevation of ACh levels in AChE-/- mice, but was without effect in AChE+/+ animals. These results were corroborated with two other specific inhibitors of AChE and BChE, tolserine and bis-norcymserine, respectively. We conclude that lack of AChE causes dramatically increased levels of extracellular ACh in the brain. Importantly, in the absence of AChE, the levels of extracellular ACh in the brain are controlled by the activity of BChE. These results point to a potential usefulness of BChE inhibitors in the treatment of central cholinergic dysfunction in which brain AChE activity is typically reduced.

The kinetic energy distribution of ground state muonic hydrogen atoms mu-p(1S) is determined from time-of-flight spectra measured at 4, 16, and 64 hPa H2 room-temperature gas. A 0.9 keV-component is discovered and attributed to radiationless deexcitation of long-lived mu-p(2S) atoms in collisions with H2 molecules. The analysis reveals a relative population of about 1%, and a pressure-dependent lifetime (e.g. (30.4 +21.4 -9.7) ns at 64 hPa) of the long-lived mu-p(2S) population, equivalent to a 2S-quench rate in mu-p(2S) + H2 collisions of (4.4 +2.1 -1.8) 10^11 s^-1 at liquid hydrogen density., 4 pages, 2 figures, accepted for publication in Physical Review Letters

Calcium overload of neurons leads to cell death and is a key feature in neurodegenerative diseases. The polycyclic amine NGP1-01 blocks L-type voltage operated calcium channels in cardiomyocytes. Here, we tested whether NGP1-01 blocks neuronal calcium channels. NGP1-01 (1 microM) inhibited depolarization-induced calcium influx by 78% in cortical neurons preloaded with fura-2 AM, with a potency similar to nimodipine. NGP1-01 (1 microM) also inhibited N-methyl-D: -aspartate (NMDA)-induced (1 mM) calcium influx by 52%, only slightly less potent than memantine. Using in vivo-microdialysis, we monitored choline release during NMDA infusion as a measure of excitotoxic membrane breakdown. Intraperitoneal injection of NGP1-01 (40 mg/kg) reduced NMDA-induced membrane breakdown by 31% (P < 0.01) while memantine (10 mg/kg) reduced choline release by 40%. Our results demonstrate that NGP1-01 simultaneously blocks both major neuronal calcium channels and is sufficiently brain-permeable. We conclude that NGP1-01 is a promising lead structure for a new class of dual-mechanism neuroprotective agents.

Probabilistic testing is very attractive due to the low test generation costs. Unfortunately, not all circuits are well random testable. To eliminate this deficiency, biased random testing has been adopted. We distinguish input signal biased (ISB) random testing, where a distribution different from the uniform one is achieved by giving each primary input an individual signal probability, from pattern biased (PB) random testing, which allows an arbitrary distribution for the input patterns.

Experimental and clinical studies give evidence for breakdown of membrane phospholipids during neurodegeneration. In the present study, we measured the levels of glycerophosphocholine (GPCh), phosphocholine (PCh), and choline, that is, water-soluble metabolites of phosphatidylcholine (PtdCho), in human cerebrospinal fluid (CSF). Among 30 cognitively normal patients the average CSF levels of GPCh, phosphocholine and choline were 3.64, 1.28, and 1.93 microM, respectively; metabolite levels did not change with increasing age. When compared with age-matched controls, patients with Alzheimer's disease had elevated levels of all choline metabolites: GPCh was significantly increased by 76% (P

The cholinergic inputs to the rat hippocampus were lesioned by intraseptal injections of 192 IgG-saporin. After 15 days, fetal septal cells were grafted into the hippocampus. Thirteen months later, hippocampal acetylcholine (ACh) release was studied by microdialysis. Lesioning reduced basal ACh release (100%) to 20% of normal, which was compensated for by the graft (71%). Infusion of the serotonin uptake inhibitor citalopram (100 microM) enhanced ACh release to the same extent (% of basal release) in all rat groups. Systemic injection of 8-OH-DPAT (0.5 mg/kg, SC), an agonist of 5-HT1A receptors, caused a smaller ACh release than citalopram. Acetylcholinesterase (AChE) staining and densitometric quantification revealed that the lesion-induced reduction of the AChE-staining density was compensated for by septal grafting. In conclusion, both histochemical and biochemical methods showed that cholinergic hippocampal parameters were drastically impaired by 192 IgG-saporin lesions, but were almost completely restored by septal grafting. The graft responded to intrinsic serotonergic regulation.

In the biosynthesis of the antiarrhythmic alkaloid ajmaline, polyneuridine aldehyde esterase (PNAE) catalyses a central reaction by transforming polyneuridine aldehyde into epi-vellosimine, which is the immediate precursor for the synthesis of the ajmalane skeleton. The PNAE cDNA was previously heterologously expressed in E. coli. Sequence alignments indicated that PNAE has a 43% identity to a hydroxynitrile lyase from Hevea brasiliensis, which is a member of the alpha/beta hydrolase superfamily. The catalytic triad, which is typical for this family, is conserved. By site-directed mutagenesis, the members of the catalytic triad were identified. For further detection of the active residues, a model of PNAE was constructed based on the X-ray crystallographic structure of hydroxynitrile lyase. The potential active site residues were selected on this model, and were mutated in order to better understand the relationship of PNAE with the alpha/beta hydrolases, and as well its mechanism of action. The results showed that PNAE is a novel member of the alpha/beta hydrolase enzyme superfamily.

This review of applications close to the market as well as those on the horizon highlights the benefits of micromoulding technology for cost-effective large-volume production of microstructured plastic components.

Microfluidic components, especially micropumps, are essential for miniaturized dosing systems, Micro Total AnalysisSystems (.i-TAS) and miniaturized labs for medical diagnosis. A variety of micropumps for these different applicationshave been developed at the Institut fur Mikrotechnik Mainz GmbH (1MM).Self-filling membrane pumps have been realized in various polymer materials. They consist of two injection-molded partsand a valve membrane with a thickness of only 2 jim. After structuring the membrane with an excimer laser, a Nd:YAGlaser is used to weld the parts. The micropump is driven by a piezoelectric actuator which renders frequencies up to 100 Hz.The maximum flow is 400 pil I mm water at up to 2.0*105 Pa. The total size of the micropump is 12*12*3 mm. Thesemeasures allow it to be integrated e.g. into dosing-systems for active substances in medical applications.For fluids with high viscosity like lubricants for high performance bearings micro gear pumps are very well suited sincetheir maximum flow rate and backpressure is higher than that of membrane pumps. Consequently, various types of gear

The density of hippocampal adenosine A1 receptors was measured in autopsy samples of six patients with dementia with either Alzheimer (three) or sclerosis type pathology (three) in hippocampus and six control patients. Kinetic parameters (Bmax and KD) were determined by means of quantitative autoradiography using [3H]8-cyclopentyl-1 ,3-dipropylxanthine as a radioligand. A significant 50% reduction of CA1 adenosine A1 receptors was observed in patients with dementia independent of the specific pathology. These results suggest that loss of hippocampal adenosine A1 receptors in dementia is not specific for Alzheimer type pathology.

The excitotoxic amino acid domoate causes anterograde amnesia and memory deficits while the excitotoxin l -β-oxalyl-amino-alanine (L-BOAA) is considered the causative agent of the motoneurone disorder, neurolathyrism. Employing quantitative autoradiography we investigated the potency of domoate and L-BOAA to inhibit [3H]kainate binding in human hippocampus. Domoate inhibited binding of [3H]kainate with inhibition constants between 5.8 ± 2.8 nM (deep layers of gyrus parahippocampalis) and 200.9 ± 247.8 nM (CA1 region of hippocampus). It was about a thousandfold more potent than L-BOAA with inhibition constants between 2.1 ± 0.5 μM (superficial layers of gyrus parahippocampalis) and 51.0 ± 41.9 μM ( CA 2 3 region of hippocampus). Interestingly, L-BOAA showed lowest affinity to [3H]kainate binding sites in those regions in which domoate showed highest affinity (e.g. CA 2 3 ) and vice versa (e.g. CA1). These data further support the notion that the neurological symptoms observed after domoate intoxication are due to an excitotoxic action at kainate receptors and provide evidence for heterogeneity of kainate receptors in human hippocampus.

The antispastic agent and N-methyl-D-aspartate (NMDA) receptor antagonist memantine has recently been proposed as a neuroprotective drug for use in patients with dementia syndromes with primarily temporal lobe pathology, e.g. senile dementia of Alzheimer type or dementia in Parkinson's disease. In a quantitative autoradiographic study in human post mortem hippocampus, memantine was able to inhibit binding of the noncompetitive NMDA-antagonist [3H]MK-801 ((+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cyclohepten-5,10-imine maleate) with inhibition constants between 3 and 10 microM, being about a factor of 10 more potent than the dissociative anaesthetic and NMDA receptor antagonist (+/-)ketamine. As these inhibition constants are well within the therapeutic concentration range of memantine, antagonism of endogenous glutamate at limbic NMDA receptors may be one molecular mechanism by which memantine is beneficial in dementia syndromes.