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The influence of random disturbances on a three-dimensional simplification of Luo–Rudy model of the cardiac action potential is studied. We show that in the parameter region, where the deterministic model is in the equilibrium regime, noise can trigger large-amplitude oscillations that correspond with pathological early afterdepolarizations (EADs). For this stochastic excitement, the phenomenon of coherence resonance was discovered. On the contrary, in another parameter zone of the model, noise can suppress EADs. We analyze these stochastic phenomena using the stochastic sensitivity functions technique, Mahalanobis distance, the methods of principal directions, and confidence domains. © 2021 The Authors. Mathematical Methods in the Applied Sciences published by John Wiley & Sons, Ltd. Russian Science Foundation, RSF: 21-11-00062 This work was supported by the Russian Science Foundation (No. 21-11-00062).

A contribution of α-Synuclein (α-Syn) to etiology of Parkinson´s disease (PD) and Dementia with Lewy bodies (DLB) is currently undisputed, while the impact of the closely related β-Synuclein (β-Syn) on these disorders remains enigmatic. β-Syn has long been considered to be an attenuator of the neurotoxic effects of α-Syn, but in a rodent model of PD β-Syn induced robust neurodegeneration in dopaminergic neurons of the substantia nigra. Given that dopaminergic nigral neurons are selectively vulnerable to neurodegeneration in PD, we now investigated if dopamine can promote the neurodegenerative potential of β-Syn. We show that in cultured rodent and human neurons a dopaminergic neurotransmitter phenotype substantially enhanced β-Syn-induced neurodegeneration, irrespective if dopamine is synthesized within neurons or up-taken from extracellular space. Nuclear magnetic resonance interaction and thioflavin-T incorporation studies demonstrated that dopamine and its oxidized metabolites 3,4-dihydroxyphenylacetaldehyde (DOPAL) and dopaminochrome (DCH) directly interact with β-Syn, thereby enabling structural and functional modifications. Interaction of DCH with β-Syn inhibits its aggregation, which might result in increased levels of neurotoxic oligomeric β-Syn. Since protection of outer mitochondrial membrane integrity prevented the additive neurodegenerative effect of dopamine and β-Syn, such oligomers might act at a mitochondrial level similar to what is suggested for α-Syn. In conclusion, our results suggest that β-Syn can play a significant pathophysiological role in etiology of PD through its interaction with dopamine metabolites and thus should be re-considered as a disease-relevant factor, at least for those symptoms of PD that depend on degeneration of nigral dopaminergic neurons.

Herein, we present the application of a copper(II) complex, [CuL1](ClO4)2 (L1: 1,3-bis(((1-methyl-1H-imidazol-2-yl)methyl)amino)propan-2-ol), 1, as a catalyst in the electrochemical driven hydrogen evolution reaction (HER) in buffered water and standardised artificial seawater. Potentiometric titrations revealed that a [CuIIHL1]3+ species is the main species in aqueous solutions at pH of 4 to 8. Complex solutions of 1 are active in the electrochemical HER at solution's pH of 4 to 8, yet, the active species is different depending on the reaction medium. In acidic and neutral phosphate buffered water, we observed the highest catalytic activity. However, the initially formed [CuIH2L1]3+ species decomposes to some extent under the reductive conditions in phosphate buffered solutions and the high activity originates from the decomposition products (elemental copper and copper oxido species) and from soluble species. In artificial seawater the catalytic activity was much lower, virtually no decomposition was observed, and likely the complex represents the active species.

The synthesis of three new ligands and their coordination behavior towards zinc ions with strongly coordinating anions and cobalt ions with weakly coordinating anions are reported. The ligands have two adjacent imidazolyl-pyridinyl and pyrazolyl-pyridinyl binding pockets, respectively, which are linked by a phenol unit. We also investigated the dynamic behavior of the ligand having the imidazolyl-pyridiyl sidearm in solution. The reaction of the ligands and ZnCl2 yielded complexes of the type [LZn2Cl3]. When we used CoII salts with weakly coordinating anions, complexes of the general formula [L2Co2]2+ were formed.

Herein, we report the synthesis of a new ligand, which is preorganised for the complexation of two metal ions and has two 1H-imidazolyl units in the outer ligand sphere. The zinc and cobalt complexes with the ligand were synthesised and fully characterised, and their solid-state structures were determined. The complexes show a highly symmetric [M2L2]2+ structural motif. The thermodynamic data, that is, the overall stability constants and redox potential of the Co2+/Co3+ couple, were determined. Potentiometric studies revealed the presence of mononuclear (below pH 7) and differently protonated dimeric species (above pH 7). The formation of distinct species was corroborated by ESI-MS measurements. Similar species were obtained for the corresponding zinc complexes. Additionally, we determined the dependence of the Co2+/Co3+ redox couple on the protonation state of the complex. The studies showed that there is a considerably strong thermodynamic coupling between the NH protons of the imidazolyl units and the oxidation state of the metal ion. Upon deprotonation of all four NH units, the potential of the redox couple shifted by ca. 1.1 V. We also synthesised the analogous ligand with N-methylimidazolyl units to investigate the influence of the NH protons on the properties of the complexes. The methylation of the NH unit has virtually no influence on the redox, magnetic and structural properties of the zinc and cobalt complexes.

A lesion to the rat rubrospinal tract is a model for traumatic spinal cord lesions and results in atrophy of the red nucleus neurons, axonal dieback, and locomotor deficits. In this study, we used adeno-associated virus (AAV)-mediated over-expression of BAG1 and ROCK2-shRNA in the red nucleus to trace [by co-expression of enhanced green fluorescent protein (EGFP)] and treat the rubrospinal tract after unilateral dorsal hemisection. We investigated the effects of targeted gene therapy on neuronal survival, axonal sprouting of the rubrospinal tract, and motor recovery 12 weeks after unilateral dorsal hemisection at Th8 in rats. In addition to the evaluation of BAG1 and ROCK2 as therapeutic targets in spinal cord injury, we aimed to demonstrate the feasibility and the limits of an AAV-mediated protein over-expression versus AAV.shRNA-mediated down-regulation in this traumatic CNS lesion model. Our results demonstrate that BAG1 and ROCK2-shRNA both promote neuronal survival of red nucleus neurons and enhance axonal sprouting proximal to the lesion.

BACKGROUND: Adeno-associated virus (AAV) vectors are used to deliver potentially therapeutic genes in clinical trials in Parkinson's disease (PD). Pre-existing immunity to AAV and a local neuroinflammatory response might negatively affect the efficacy of such AAV-mediated gene delivery. METHODS: We pre-immunized rats with wild-type AAV-2. Three months later, we created PD-like lesions by intrastriatal injections of 6-hydroxydopamine (6-OHDA) in 50% of the animals. One month later, we injected AAV2 vector expressing enhanced green fluorescent protein (eGFP) in the striatum. Using immunohistochemistry, we assessed eGFP expression, microglia activation and CD8 T cell infiltration. We also measured AAV-2 specific neutralizing antibody titers in the serum. RESULTS: The number of striatal cells transduced with AAV2 vector expressing eGFP was reduced by 71% in rats pre-immunized with wild-type AAV2 compared to non-immunized animals. We detected elevated numbers of OX6(+) activated microglia in the striatum and circulating AAV2-specific neutralizing antibodies in pre-immunized rats. We also observed that the intrastriatal 6-OHDA injection promoted CD8(+) T cell infiltration and enhanced microglia activation. Nevertheless, the 6-OHDA lesion did not alter AAV2-mediated expression of eGFP in either pre-immunized or non-immunized rats. CONCLUSIONS: Our findings indicate that intracerebral AAV2-based gene therapy is compromised in rats with pre-existing immunity to AAV2. By contrast, a local neuroinflammatory response, caused by intrastriatal a 6-OHDA injection, does not affect viral vector-mediated transgene expression. Our results emphasize the importance of monitoring circulating AAV-specific neutralizing antibodies in patients undergoing intracerebral gene therapy using AAV vectors. Copyright © 2014 John Wiley & Sons, Ltd. peerReviewed

The D4 receptor is of high interest for research and clinical application but puts high demands on appropriate radioligands to be useful tools for investigation. Search for adequate radioligands suitable for in vivo imaging is therefore still in progress. The potential neuroleptic drug 6-(4-[4-fluorobenzyl]piperazin-1-yl)benzodioxin shows high affinity and selectivity to the D4 receptor. Derivatization of this lead structure by adding hydrophilic moieties was carried out in order to lower its lipophilicity what led to three new putative dopamine receptor D4 ligands. A comprehensive description of the syntheses of standard compounds and corresponding labeling precursors is given which were obtained in satisfactory yields. Furthermore, the radiosyntheses by direct 18F-labeling and build-up synthesis were compared. All derivatives of 6-(4-[4-fluorobenzyl]-piperazin-1-yl)benzodioxin were successfully synthesized in 18F-labeled form with radiochemical yields of 9–35% and molar activities of 30–60 GBq/µmol using one-pot procedures. Copyright © 2013 John Wiley & Sons, Ltd.

Objective Whereas the contribution of α-synuclein to neurodegeneration in Parkinson disease is well accepted, the putative impact of its close homologue, β-synuclein, is enigmatic. β-Synuclein is widely expressed throughout the central nervous system, as is α-synuclein, but the physiological functions of both proteins remain unknown. Recent findings have supported the view that β-synuclein can act as an ameliorating regulator of α-synuclein–induced neurotoxicity, having neuroprotective rather than neurodegenerative capabilities, and being nonaggregating due to the absence of most of the aggregation-promoting NAC domain. However, a mutation of β-synuclein linked to dementia with Lewy bodies rendered the protein neurotoxic in transgenic mice, and fibrillation of β-synuclein has been demonstrated in vitro. Methods Neurotoxicity and aggregation properties of α-, β-, and γ-synuclein were comparatively elucidated in the rat nigro-striatal projection and in cultured neurons. Results Supporting the hypothesis that β-synuclein can act as a neurodegeneration-inducing factor, we demonstrated that wild-type β-synuclein is neurotoxic for cultured primary neurons. Furthermore, β-synuclein formed proteinase K–resistant aggregates in dopaminergic neurons in vivo, leading to pronounced and progressive neurodegeneration in rats. Expression of β-synuclein caused mitochondrial fragmentation, but this fragmentation did not render mitochondria nonfunctional in terms of ion handling and respiration even at late stages of neurodegeneration. A comparison of the neurodegenerative effects induced by α-, β-, and γ-synuclein revealed that β-synuclein was eventually as neurotoxic as α-synuclein for nigral dopaminergic neurons, whereas γ-synuclein proved to be nontoxic and had very low aggregation propensity. Interpretation Our results suggest that the role of β-synuclein as a putative modulator of neuropathology in aggregopathies like Parkinson disease and dementia with Lewy bodies needs to be revisited. Ann Neurol 2013;74:109–118

A recently published palladium-catalyzed preparation of fluoroarenes starting from caesium fluoride attracted interest as a new alternative for radiofluorination. To test this method, a suitable protocol for the synthesis of 4-[18F]fluorotoluene and 1-[18F]fluoronaphthalene as model systems has been developed. The possibility to perform the reaction under no-carrier-added condition was of special interest. It was found out, however, that the reaction requires the presence of carrier, thus limiting the method to syntheses of radiotracers with low specific activity. Copyright © 2012 John Wiley & Sons, Ltd.

2 Centre of Molecular Physiology of the Brain (CMPB) at University Medicine GDepartment of Neurology, GGermany Non-technical summary Optical imaging is widely used to map functional areas of the cerebral cortex. We present a method for fast fluorescence imaging of map-level cortical activity using a calciumindicatorprotein.Sensory-evokedneuronalactivitycanbeimagedrepeatedlyinthesame mouseover weeks, enablingnew opportunitiesforthe longitudinalstudyof corticalfunctionand dysfunction. We hope this method will be flexibly applied across different cortical areas and to a variety of newly developed genetically encoded calcium and voltage sensors. Abstract In vivo optical imaging can reveal the dynamics of large-scale cortical activity, but methodsforchronicrecordingarelimited.Herewepresentatechniqueforlong-terminvestigation of cortical map dynamics using wide-field ratiometric fluorescence imaging of the genetically encoded calcium indicator (GECI) Yellow Cameleon 3.60. We find that wide-field GECI signals reportsensory-evokedactivityinanaesthetizedmousesomatosensorycortexwithhighsensitivity and spatiotemporal precision, and furthermore, can be measured repeatedly in separate imaging sessions over multiple weeks. This method opens new possibilities for the longitudinal study of stability and plasticity of cortical sensory representations.

Prestin, a transporter-like protein of the SLC26A family, acts as a piezoelectric transducer that mediates the fast electromotility of outer hair cells required for cochlear amplification and auditory acuity in mammals. Non-mammalian prestin orthologues are anion transporters without piezoelectric activity. Here, we generated synthetic prestin (SynPres), a chimera of mammalian and non-mammalian prestin exhibiting both, piezoelectric properties and anion transport. SynPres delineates two distinct domains in the protein’s transmembrane core that are necessary and sufficient for generating electromotility and associated non-linear charge movement (NLC). Functional analysis of SynPres showed that the amplitude of NLC and hence electromotility are determined by the transport of monovalent anions. Thus, prestin-mediated electromotility is a dual-step process: transport of anions by an alternate access cycle, followed by an anion-dependent transition generating electromotility. The findings define structural and functional determinants of prestin’s piezoelectric activity and indicate that the electromechanical process

Consumers worldwide are increasingly concerned with sustainable production and consumption. Recently, a comprehensive study ranked 17 countries in regard to their environmentally friendly behaviour among consumers. Brazil was one of the top countries in the list. Yet, several studies highlight significant differences between consumers' intentions to consume ethically, and their actual purchase behaviour: the so-called ‘Attitude-Behaviour Gap'. In developing countries, few studies have been conducted on this issue. The objective of this study is therefore to investigate the gap between citizens' sustainability-related attitudes and food purchasing behaviour using empirical data from Brazil. To this end, Brazilian citizens' attitudes towards pig production systems were mapped through conjoint analysis and their coexistence with relevant pork product-related purchasing behaviour of consumers was investigated through cluster analysis. The conjoint experiment was carried out with empirical data collected from 475 respondents surveyed in the South and Center-West regions of Brazil. The results of the conjoint analysis were used for a subsequent cluster analysis in order to identify clusters of Brazilian citizens with diversified attitudes towards pig production systems, using socio-demographics, attitudes towards sustainability-related themes that are expected to influence the way they evaluate pig production systems, and consumption frequency of various pork products as clusters' background information. Three clusters were identified as ‘indifferent', ‘environmental conscious' and ‘sustainability-oriented' citizens. Although attitudes towards environment and nature had indeed an influence on citizens' specific attitudes towards pig farming at the cluster level, the relationship between ‘citizenship' and consumption behaviour was found to be weak. This finding is similar to previous research conducted with European consumers: what people (in their role of citizens) think about pig production systems does not appear to significantly influence their pork consumption choices. Improvements in the integrated management of this chain would better meet consumers' sustainability-related expectations towards pig production systems.

Two trivalent constructs consisting of single-chain Fv antibody fragments (scFvs) specific for the interleukin-3 receptor alpha chain (CD123), CD33 and the Fcgamma-receptor III (CD16) were designed and characterized for the elimination of acute myeloid leukaemia (AML) cells. The dual targeting single-chain Fv triplebody (sctb) [123 x ds16 x 33] and the mono targeting sctb [123 x ds16 x 123] both specifically bound their respective target antigens and were stable in human serum at 37 degrees C for at least 5 d. Both constructs induced potent antibody-dependent cellular cytotoxicity (ADCC) of two different AML-derived CD33- and CD123 double-positive cell lines in the low picomolar range using isolated mononuclear cells (MNCs) as effector cells. In these experiments the dual targeting molecule produced significantly stronger lysis than the mono targeting agent. In addition, the sctbs showed a high potency in mediating ADCC of primary leukaemia cells isolated from peripheral blood or bone marrow of seven AML patients. Hence, these novel molecules displayed potent anti-leukaemic effects against AML cells in vitro and represent attractive candidates for further preclinical development.

Rett syndrome caused by MeCP2 mutations is a devastating neurodevelopmental disorder accompanied by severe breathing irregularities. Using transduction of organotypic slices from model MeCP2–/y mice with neuron-specific calcium sensor protein D3cpv, we examined the slow calcium buffering in neurons in pre-Botzinger complex (preBotC), a component of the complex respiratory network. Examination of wild-type (WT) and MeCP2 null mice showed clear differences in the spatial organisations of neurons in preBotC and also in the disturbances in calcium homeostasis in mutant mice during early postnatal development. Deregulated calcium buffering in MeCP2–/y neurons was indicated by increased amplitude and kinetics of depolarisation-induced calcium transients. Both effects were related to an insufficient calcium uptake into the endoplasmic reticulum that was restored after pretreatment with brain-derived neurotrophic factor (BNDF). Conversely, the inhibition of BDNF signalling in WT neurons produced disturbances similar to those observed in MeCP2–/y mice. Brief hypoxia and calcium release from internal stores induced global calcium increases, after which the processes of many MeCP2–/y neurons were retracted, an effect that was also corrected by pretreatment with BDNF. The data obtained point to a tight connection between calcium homeostasis and long-term changes in neuronal connectivity. We therefore propose that calcium-dependent retraction of neurites in preBotC neurons can cause remodelling of the neuronal network during development and set up the conditions for appearance of breathing irregularities in Rett model mice.

Co-Immobilization of dextransucrase (DS) and dextranase (DN) into calcium alginate includes the co-entrapment of soluble DS and adsorbed DN. DS converts sucrose into dextran, which is the substrate for DN, so that isomalto-oligosaccharides (IMOs) are follow-up products of dextran hydrolysis. The boundary conditions for the successful preparation are investigated with respect to choice of DN adsorbate, surface modifications using blotting agents and optimal enzyme activity ratios. Further, repetitive batch experiments suggest the selection of medium activity ratios for continuous use (0.3 U(DN)U(-1) (DS), e.g.). Product formation at various cosubstrate:substrate concentrations as well as at different DN:DS ratios are discussed. Moreover, the complexity of the bi-enzymatic system can be reduced considering the molar ratios of cosubstrate:substrate (glucose:sucrose). Based on these factors, a mechanistic kinetic model is developed, which distinguishes the corresponding contributions of the two enzymes upon overall product formation. In general, at low glucose:sucrose ratios isomaltose synthesis is featured primarily by DN action. Yet with increasing amounts of glucose both the quantity and quality of DN substrate changes, so that its contribution to product formation decreases in an exponential manner; still the overall product yield continuously increases due to enhanced DS contribution.

Functional characterization of disease-related proteins, their splice variants and dominant negative mutants in the context of complex CNS tissues such as brain and retina is frequently assessed by in vivo gene transfer. For correct interpretation of results it is imperative that the protein under investigation is unambiguously detected in the transduced cell types and can be distinguished from any endogenously expressed physiological variants. Therefore the first systematic evaluation of epitope tags used to trace ectopically expressed proteins in the central nervous system is presented here. Substantial differences in the performances of various epitope tag-antibody combinations with respect to sensitivity, specificity and influence of the epitope tag on the fusion protein are elucidated. Epitope tags already established for protein detection in vitro and to some extent in vivo (c-Myc, HA and FLAG tags) were immunohistochemically detected with high sensitivity. However, detection of these tags revealed problems with background staining and we also document structural and functional influence of the tags on the fusion protein. In order to prevent such unwanted side-effects, epitope tags which have not yet been used for in vivo applications (IRS, EE and AU1 tags) were characterized in brain, retina and cultured neurons. While use of the IRS and EE tags was hindered by low sensitivity or specificity, optimal results were obtained with the AU1 epitope, which may develop into a standard tool for detection of ectopic protein expression in the central nervous system.

Zusammenfassung Hintergrund: Anogenitaldermatosen (AGD) sind haufige und psychisch sehr belastende Erkrankungen. Klinisch ist oft unklar, ob eine Kontaktallergie oder irritative Faktoren beteiligt sind. Bezuglich Therapie und Prophylaxe ist von Bedeutung, welche Allergene oder Irritantien dann die Hauptrolle spielen. Patienten und Methoden: Daten des Informationsverbundes Dermatologischer Kliniken (IVDK, Zentrale in Gottingen) von 1999 bis 2003 wurden ausgewertet. 1 168 Patienten mit der Hauptdiagnose AGD wurden bezuglich klinischer Parameter und der Ergebnisse der Epikutantestung mit dem Gesamtkollektiv verglichen. Die Reaktionsquoten wurden alters- und geschlechtsstandardisiert. Ergebnisse: Der Verdacht auf ein allergisches Kontaktekzem bestand bei 39,5 % vor der Epikutantestung. Nach der Testung wurde bei 24,6 % die AGD als allergisches Kontaktekzem eingeordnet; eine chronisch irritative Dermatitis wurde bei 11,8 % diagnostiziert. Sonstige Diagnosen waren „Balanitis”, Lichen sclerosus et atrophicus sowie Herpes genitalis. Signifikant erhohte Sensibilisierungsquoten gegenuber dem Kontrollkollektiv zeigten sich bei Patienten mit AGD fur Cinchocain (6,6 %), Bufexamac (3,5 %) und Benzocain (2,4 %). Sofern irritative Faktoren eine Rolle als Ko-Faktoren spielten (n = 422), wurden Feuchtigkeit (38,4 %), okklusives Milieu (30,3 %), mechanische Belastung (4,7 %) und Hitze (3,6 %) genannt. Schlussfolgerung: Sensibilisierungen auf Cinchocain, Benzocain und Bufexamac kommen bei Patienten mit AGD haufiger vor als bei Patienten mit anderen Dermatosen. Daher sollten Medikamente mit diesen Wirkstoffen in der Praxis sehr zuruckhaltend eingesetzt werden. Die Inhaltsstoffe von Wasch-/Pflegemitteln sowie Kontrazeptiva verschiedenen Typs scheinen nach der Literatur insgesamt selten zu einer Kontaktallergie zu fuhren, obwohl kasuistische Mitteilungen vorhanden sind. Die ausfuhrliche Testung mit der DKG-Standardreihe, den oben genannten Hauptsensibilisatoren Cinchocain, Benzocain und Bufexamac, und insbesondere mit den vom Patienten verwendeten Pflege- und Hilfsmitteln wird empfohlen. Summary Background: Anogenital dermatoses (AGD) are common and often very distressing. Clinically it is often unclear if allergic contact dermatitis or irritant dermatitis is involved. In order to optimize therapy and prophylaxis, it is essential to identify relevant allergens or irritants. Patients and Methods: Data of the Information Network of Departments of Dermatology (IVDK, data center in Gottingen) collected between 1999 and 2003 were analyzed. The anogenital area was involved in 1 168 patients with suspected allergic contact dermatitis. Clinical variables and patch test results were statistically compared with the remaining IVDK patch test population, the latter standardized for age and sex. Results: Allergic contact dermatitis had been suspected prior to patch testing in 39.5 %, while in 24.6 % this diagnosis was eventually confirmed. Irritant contact dermatitis was diagnosed in 11.8 %. Other diagnoses, included balanitis, lichen sclerosus et atrophicus and herpes genitalis. Positive reactions to cinchocaine (6.6 %), bufexamac (3.5 %) and benzocaine (2.4 %) were observed significantly more often among patients with anogenital dermatitis. Among those in whom co-factors were considered important (n = 422), wetness (38.4 %), occlusion (30.3 %), mechanical strain (4.7 %) and heat (3.6 %) were mentioned as irritation factors. Conclusion: Because of the significantly higher frequency of sensitization to cinchocaine, benzocaine and bufexamac in patients with anogenital dermatitis, these ingredients should be used only with caution. According to the literature, ingredients of toiletries, cosmetics and contraceptives of any kind seem to cause allergic contact dermatitis rarely although there are several case reports. Comprehensive patch test including the standard series plus major sensitizers such as cinchocaine, benzocaine and bufexamac, and in particular patients' own skin care products, is recommended.

The brain parenchyma consists of several different cell types, such as neurones, astrocytes, microglia, oligodendroglia and epithelial cells, which are morphologically and functionally intermingled in highly complex three-dimensional structures. These different cell types are also present in cultures of brain cells prepared to serve as model systems of CNS physiology. Gene transfer, either in a therapeutic attempt or in basic research, is a fascinating and promising tool to manipulate both the complex physiology of the brain and that of isolated neuronal cells. Viral vectors based on the parvovirus, adeno-associated virus (AAV), have emerged as powerful transgene delivery vehicles. Here we describe highly efficient targeting of AAV vectors to either neurones or astrocytes in cultured primary brain cell cultures. We also show that transcriptional targeting can be achieved by the use of small promoters, significantly boosting the transgene capacity of the recombinant viral genome. However, we also demonstrate that successful targeting of a vector in vitro does not necessarily imply that the same targeting works in the adult brain. Cross-packaging the AAV-2 genome in capsids of other serotypes adds additional benefits to this vector system. In the brain, the serotype-5 capsid allows for drastically increased spread of the recombinant vector as compared to the serotype-2 capsid. Finally, we emphasize the optimal targeting approach, in which the natural tropism of a vector for a specific cell type is employed. Taken together, these data demonstrate the flexibility which AAV-based vector systems offer in physiological research.

Inhibitor-of-differentiation 2 (Id2) belongs to a family of transcriptional modulators that are characterized by a helix loop helix region but lack the basic amino acid domain. During development, Id2 antagonizes differentiation mediated by the retinoblastoma protein, probably by scavenging downstream E-box basic helix-loop-helix proteins. Here, using differential display RT-PCR, we identify Id2 as an induced gene during serum and potassium deprivation-induced apoptosis of cerebellar granule neurons. Consistent with a biological role for induced Id2 messenger RNA and protein expression in neuronal cell death, expression of Id2 antisense RNA, or targeted deletion of the Id2 gene in neurons from Id2 knock-out mice, protect from apoptosis. Further, gene transfer- mediated overexpression of Id2 induces neuronal cell death both in high potassium and low potassium conditions. Thus, the present study defines a role for Id2 in the modulation of neuronal apoptosis.

Adult rat retinal ganglion cells undergo degeneration after optic nerve transection. Repeated intraocular injection of glial cell-line derived neurotrophic factor (GDNF) has been shown to be efficient in enhancing retinal ganglion cell survival following optic nerve axotomy. In the present study we evaluated the potential survival-promoting effect of adenovirally administered GDNF on axotomized retinal ganglion cells. A single intravitreal injection [7 x 107 plaque-forming units (pfu) or 7 x 108 pfu] of an adenoviral vector expressing the rat GDNF gene from a cytomegalovirus promoter enhanced retinal ganglion cell survival 14 days after axotomy by 67 and 125%, respectively, when compared to control animals. Intraocular administration of the vector rescued 12.6 and 23%, respectively, of the retinal ganglion cells which would otherwise have died after axotomy. An increase in retinal GDNF protein and specific virally transduced GDNF mRNA expression was detected following intraocular vector application. Our data support previous findings showing that adenoviral delivery of neurotrophic factors to the vitreous body is a feasible approach for the prevention of axotomy-induced retinal ganglion cell death in vivo and may constitute a relevant strategy for future treatment in traumatic brain injury and ensuing neurodegeneration.

The swelling properties of physisorbed polyelectrolyte multilayer self-assemblies with alternating polyion charge in humid air and in aqueous environment were investigated via X-ray and neutron reflectometry as well as optically, using surface plasmon spectroscopy. The sorption behavior was similar to that found for neutral polymers and was related to an internal screening of the charges of the adjacent layers owing to the high entanglement of the polyelectrolyte chains and the resulting low mobility of the polymer segments. The screening was found to be incomplete only in the top layer, resulting in a net charged surface.

The formation and structure of slip lines, recorded by video during tensile deformation and supplemented by EM replica after deformation at room temperature is compared for Cu-5, 10, and 15 at% Al single crystals and polycrystals. Both show the same fine structure of slip lines in the slip bands and localization of slip increasing with solute concentration. In the first, stages of deformation, the active slip bands in single crystals are concentrated in a Luders band front propagating along the crystal length, while in the polycrystals (typical grain size up to 100 μm) the grains are activated at random along the crystal length starting with the largest grains and with preferred slip systems (mostly only 2 or 3) mostly according to Schmid's law, but activated with different succession in parts of the grains. The kinetics of single slip bands is similar in both poly- and single crystals, indicating similar elementary processes for their activation and development.

OBJECTIVES: To search for a potential role of endothelin-1 (ET-1), a potent vasoconstrictor and presumably neurotoxic 21-amino acid peptide, for dysfunction of brain signal processing and cerebrovascular morbidity in nondemented patients with cerebral arteriosclerosis. DESIGN: Cross-sectional study with longitudinal follow-up. SETTING: University-affiliated teaching hospital. PARTICIPANTS: A total of 106 nondemented patients with significant stenosis of either the internal carotid (cAD, cases; n = 63, mean age ± SD, 62 ± 7 years) or peripheral arteries (pAD, disease controls; n = 43, 60 ± 11 years) were investigated before carotid endarterectomy and bypass surgery, respectively. After a mean follow-up of about 19 months, cerebrovascular morbidity of the cAD and pAD patients was evaluated by phone. MEASUREMENTS: Brain signal processing functions by event-related visual P300 potentials; cerebrovascular events by a structured telephone interview; the extent of arteriosclerosis by venous ET-1 concentration. RESULTS: Venous ET-1 levels were elevated in both cAD and pAD patient groups, but to the same degree. In these patients, ET-1 concentration was correlated slightly with diastolic blood pressure (r = .334, P = .0326, stepwise regression). Only in cAD patients with ET-1 levels above the 75th percentile were P300 latencies markedly prolonged compared with their lower ET-1 level counterparts. Furthermore, the P300 latencies of the cAD patients, but not of the pAD patients, correlated positively with venous ET-1 concentration and inversely with pack years of smoking (r = .728, P = .0002; stepwise regression). In contrast to base-line P300 abnormalities and classical risk factors (e.g., hypertension), high ET-1 levels predicted an increased cerebrovascular morbidity of cAD, but not of pAD, patients (P = .0044; Mantel-Cox test). CONCLUSIONS: In nondemented patients with cerebral arteriosclerosis, endothelin-1 is associated with P300 abnormalities reflecting subclinical dysfunction of brain signal processing. In the long-term, high venous ET-1 levels also appear to predict a higher cerebrovascular morbidity of cAD patients even after carotid endarterectomy.

Vigilin is a member of the KH protein family and contains 14 tandemly arranged potential RNA-binding domains. Between KH domains 2 and 3 we have identified a nuclear localization sequence by cloning this sequence into the NH2-terminal region of phage T7 RNA polymerase as a reporter protein and by showing its transfer into the nucleus. Furthermore we provide experimental evidence that Vigilin is present both in the nucleus and in the cytoplasm in similar concentrations. These observations support the notion that Vigilin may shuttle between nucleus and cytoplasm presumably in contact with RNA molecules.