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Natural zeolites of sedimentary origin are widely used in agriculture both as individual fertilizer and a mix of mineral and organic fertilizers. Natural zeolites are crystalline nanoporous hydrated aluminosilicates. Fertilizer of prolonged activity enriched with macro- and microelements is obtained by fusing zeolite with dehydrated ammonium using nanotechnological method of modification. The structure and some physical and chemical properties of a novel nanomaterial were studied by the methods of X-ray diffraction, IR-spectroscopy, absorption and thermal analysis. It was shown that the obtained fertilizer may be used in both protected and open grounds.

In the present study we evaluated effects of selective cholinergic or GABAergic lesions of the nucleus basalis magnocellularis (NBM) using immunotxins 192 IgG-saporin and GAT1-SAP on place and response learning in plus-shaped maze. In current behavioral paradigm rats learned food-rewarded mazes that were efficiently learned using either place or turning strategies. A histological evaluation indicated that 192 IgG-saporin lesions specifically depleted cholinergic neurons but did not result in noticeable damage to the GABAergic cells within NBM. GAT1-SAP lesions resulted extensive damage of GABAergic and a mild reduction of cholinergic NBM neurons. The results of present behavioral experiments showed, that selective lesions of cholinergic or GABAergic neurons in the NBM impair, but do not abolish, the animal's ability to learn location of rewarded arm of maze (place learning) or a skilled motor behavior (response learning). Our findings suggest the role of NBM cholinergic and GABAergic cortical projection neurons in processing of cognitive information. We suggested that lesions of NBM projections to the cortex modulate learning-mediated plasticity and impair both place and response learning.

In the present study, the possible beneficial effect of memantine on the Okadaic Acid (OA) induced spatial short-term memory impairment was examined in spatial alternation task, and the neuroprotective potential of memantine on OA-induced structural changes in the hippocampus was evaluated by Nissl staining. OA was dissolved in artificial cerebrospinal fluid (aCSF) and injected intracerebroventriculary (ICV) 200 ng in a volume of 10 μl bilaterally. Vehicle control received aCSF ICV bilaterally. Control and OA injected rats were divided into 2 subgroups injected i.p. with saline or memantine (5 mg/kg). Memantine or saline were given daily for 13 days starting from the day of OA injection. Behavioral study showed that bilateral ICV microinjection of OA induced impairment in spatial short-term memory. Nissl staining in the present study showed that the ICV microinjection of OA significantly decreased the number of surviving pyramidal neurons in the CA1 region of the hippocampus. Chronic administration of memantine effectively attenuated OA induced spatial short-term memory impairment and the OA-induced neuropathological changes in the hippocampus. Therefore, ICV injection of OA can be used as an experimental model to study mechanisms of neurodegeneration and define novel therapeutics targets for AD pathology.

WOS: 000271826300009 PubMed ID: 19845380 The effect of both nanoparticles and low molecular weight borate esters on the ionic conductivity of crosslinked polysiloxanes was systematically investigated by means of measuring conductivity spectra in the impedance regime at temperatures between -30 and 90 degrees C. Salt-in-polymer electrolytes were prepared by dissolving lithium triflate (LiSO(3)CF(3)) in comblike polysiloxanes bearing one methyl and one oligoether side group per silicon. An amount of 10 mol % of the oligoether side groups exhibited a terminal allytrimethoxysilane serving as a cross-linker moiety (T(0.1)OPS). Thus prepared polymer electrolyte membranes were completely amorphous and mechanically stable with an optimum conductivity value of 5.7 x 10(-5) S.cm(-1) at 15 wt % of lithium triflate (LiSO(3)CF(3)) at room temperature (T(0.1)OPS + 15 wt % LiSO(3)CF(3)). Further investigations concerned the influence of additives, i.e., nanosized ceramic tillers (alpha-Al(2)O(3) and SiO(2), UP to 10 wt %) as well as two low molecular weight borate esters (tris(2-(2-methoxyethoxy)ethyl) borate (B2) and tris(2-(2-(2-methoxyethoxy)ethoxy)ethyl) borate (B3)) with maximum concentrations of 40 wt % as referred to polysiloxane T(0.1)OPS. The addition of borate esters resulted in a considerable increase of the conductivity, while still maintaining the mechanical stability. Optimum conductivities of 3.7 x 10(-5) and 1.6 x 10(-4) S.cm(-1) were measured for B2 and B3, respectively, at room temperature. A fit of the temperature-dependent DC conductivity by the empirical Vogel-Tammann-Fulcher (VTF) equation showed that there was an increased number density of mobile charge carriers in the case of borate esters as additives. However, the shape of the conductivity spectra in the dispersive regime changed considerably in going from nanoparticles as additives to borate esters. A careful and consistent modeling of the conductivity spectra and of the temperature dependence of the DC conductivity was done within the framework of the MIGRATION concept. The result was that the addition of borate esters to the polymer host most probably increased both number density of mobile charge carriers as well as their mobility. Deutsche ForschungsgemeinschaftGerman Research Foundation (DFG) [SFB 458] We are grateful to the Deutsche Forschungsgemeinschaft for the financial support of this work within SFB 458, Y. Karatas and N. Kaskhedikar would like to thank the International Graduate School of Chemistry at the University of Muenster for their doctoral fellowships.

The aim of this study was to investigate the role of the medial septal (MS) GABAergic cells in hippocampal dependent spatial learning using the immunotoxin GAT1-SAP to produce selective lesions of GABAergic MS neurons. In current study rats were trained in a visible platform version of the Morris water maze in which either a place or cue strategy could be used to escape successfully. Immunohistochemical studies showed that intraseptal injection of GAT1-SAP extensively damaged GABAergic MS neurons and spared most cholinergic neurons. The rats' responses on the competition test were classified as either cue or place, based on the swim path for those trials. An overview of the data from both competition trials for each group show that the control rats in 14 trials out of 16 competition test trial used place strategy, while MS-lesioned ones used this strategy in 2 trials only. Decreased place-bias in MS-lesioned rats compared to the control rats was significant (P0.01). The data obtained in the control and GAT1-SAP lesioned animals in the present study, demonstrate that lesioned rats were impaired in hidden platform trials during training, and displayed a pronounced cue-bias in competition tests. Therefore, above data suggest involvement of the MS GABAergic neurons in organization of the spatial map-driven behavior and this structure, along with the hippocampus, should be viewed as a constituent of the functional system responsible for the cognitive types of spatial memory.

Substituted cyclotriphosphazenes were used to prepare lithium ion conducting polymer networks. Two types of compounds were synthesized starting with the precursor hexachlorocyclotriphosphazene (HCCP): Type I (CVEEP) in which all the chlorine atoms in HCCP were replaced by vinyloxyethoxyethoxy groups (VEE = –OCH 2 CH 2 OCH 2 CH 2 OCH CH 2 ), and type II (CVMEEP) in which half of the chlorine was replaced by VEE and the other half by methoxyethoxyethoxy groups (MEE = –OCH 2 CH 2 OCH 2 CH 2 OCH 3 ). The terminal vinyl groups were used to build up a network by a thermally initiated cross-linking of lithium salt containing membranes. Polymer electrolytes with dissolved LiSO 3 CF 3 and LiN(SO 2 CF 3 ) 2 were investigated by impedance measurements. The ionic conductivity of CVMEEP with 10 wt.% LiSO 3 CF 3 was 3.2 × 10 − 5 S/cm at 30 °C and 4.1 × 10 − 4 S/cm at 90 °C. Lower conductivity values in the range 10 − 8 –10 − 9 S/cm were obtained at 30 °C for the highly crosslinked CVEEP. An interesting polymer electrolyte with good mechanical properties and a good conductivity of 1.3 × 10 − 5 S/cm (30 °C) was obtained from a solution of MEEP (= poly[bis(methoxy–ethoxy–ethoxy)phosphazene]) and LiSO 3 CF 3 in CVEEP as an interpenetrating network.

Composite salt-in-polymer electrolyte membranes were prepared from poly[(bis(2-methoxyethyl)amino)1−x(n-propylamino)x-phosphazene] (BMEAP) with dissolved LiCF3SO3 and dispersed Al2O3 nanoparticles (40 nm). Membranes with good mechanical stability were obtained. Low ionic conductivities were found in particle free membranes with maximum conductivities at 10 wt.% LiCF3SO3 ranging from 3.1 × 10− 7 S/cm at 30 °C to 1.8 × 10− 5 S/cm at 90 °C. For the composite membranes, addition of 2 wt.% Al2O3 nanoparticles leads to a steep increase of the conductivity by almost two orders of magnitude as compared to the homogeneous membranes. The highest room temperature conductivity for the investigated BMEAP–LiCF3SO3–Al2O3 composite systems was 10− 5 S/cm.

Proton conducting membranes have been prepared using sulfonated poly[bis(phenoxy)phosphazene] (s-BPP) trapped in a cross-linked interpenetrating hydrophilic network of hexa(vinyloxyethoxyethoxy)cyclotriphosphazene (CVEEP). Membranes with good mechanical and thermal stabilities were obtained exhibiting high ion exchange capacities in the range of 1.62–1.79 mmol/g. The proton conductivity was measured as a function of water partial pressure in nitrogen (0 mbar to 25 mbar) in the temperature range 25 °C to 75 °C. At 25 mbar water partial pressure and 75 °C, a conductivity of 2.2 × 10− 4 S/cm was obtained for s-BPP with a network made of 50 wt.% CVEEP. After immersion in water, the conductivity increased up to 0.013 S/cm at 25 °C. The hydrophilic nature of the CVEEP network stabilizes the water content and enhances the proton conductivity at elevated temperatures.

A series of comb-like polysiloxanes was prepared as the base polymer for solvent-free polymer electrolyte membranes. Hydrosnylationon of poly(methylhydrosiloxane) (PMHS) was used to substitute hydrogen by the two types of side groups tetraethylene glycol allyl methyl ether and allyltrimethoxysilane (ATMS) with varying molar ratios between 5 and 40 mol-% ATMS. The AIMS side groups served to cross-link as-prepared polymer electrolyte membranes after dissolving lithium trifluoromethylsulfo nate (triflate) or lithium bis(trifluoromethylsulfonyl)imide. The ionic conductivities of these salt-in-polymer membranes prepared with a constant concentration of 10 wt.-% lithium triflate showed a maximum conductivity of 4.6×10 -5 S. cm -1 at 30°C for 10 mol-% ATMS substitution. In another series of experiments with the ATMS substitution held constant at 10 mol-%, the salt concentration was varied yielding a maximum conductivity of 1,4 x 10 -4 S cm -1 at 30°C for 12.5 wt.-% lithium triflate.

Random copolymers of the polyphosphazene [NPR2]n have been synthesized via living ionic polymerization with mixed substituents at the phosphorus atoms (i.e., R = bis(2-methoxy-ethyl)amino and n-propylamino). The polymers melt at 190 °C and start to decompose above 300 °C. Thin polymer electrolyte membranes were prepared by solution casting with dissolved lithium triflate (LiSO3CF3) and with NaI. The transparent membranes showed favorable mechanical properties below 100 °C. Tg values ranged between −50 and −36 °C. Membranes with 10 wt % LiSO3CF3 (corresponding to the atomic ratio Li/(O + N) = 1/30) showed rather low conductivities between 3.2 × 10-7 S cm-1 at 30 °C and 1.9 × 10-5 S cm-1 at 100 °C as determined from impedance measurements. The dispersion of 4 wt % Al2O3 nanoparticles in the polyphosphazene membranes with 10 wt % LiSO3CF3, however, leads to an increase of the conductivities by 2 orders of magnitude, that is, 1.0 × 10-5 S cm-1 at 30 °C and 1.5 × 10-3 S cm-1 at 100 °C. The heterogeneously dope...

Two polyphosphazene-based electrolytes were synthesized. The first was the polymer electrolyte poly[bis(methoxy-ethoxy-ethoxy-)phosphazene] (MEEP) with lithium triflate, the second was sodium salt of sulfonated poly[bis(phenoxyethoxy)phosphazene] (PhEP) as a polyelectrolyte. The “living” cationic polymerization of the monomer Cl 3 PNSi(CH 3 ) 3 was used to obtain the polymer precursor poly(dichlorophosphazene). The final polymers were obtained from the precursor by nucleophilic substitution. The monomer was synthesized via a recently reported route. The emphasis lied on testing the accessability and properties of electrolyte materials obtained by the newer synthetic techniques. The chosen synthetic approach proved to be a suitable and straightforward access to functionalized polyphosphazenes and therefore to corresponding polymer-based electrolytes. The ionic conductivity was studied by impedance spectroscopy in the temperature range between 20 and 70 °C. The temperature dependence of the conductivity of MEEP/LiCF 3 SO 3 is described by the Vogel–Tamman–Fulcher (VTF) equation. At 25 °C, its conductivity was 10 −5 S cm −1 . The conductivity of the sodium salt of sulfonated PhEP was especially sensitive to a changing water partial pressure and is useful as humidity-sensitive sensor. In the presence of a water-saturated atmosphere, sulfonated PhEP showed a conductivity of 4.7×10 −2 at 25 °C.

These experiments examined the effects of acute administration of memantine (2.5 or 5 mg/kg) or saline on spatial memory and learning process within single sessions, on place versions of food-rewarded maze in MS electrolytic lesioned and sham-lesioned rats. Sham-lesioned rats trained in the place task learned more rapidly than did MS electrolytic lesioned rats. This fact certifies for obvious deficit of the place learning performance strategy in the MS-lesioned rats. The results indicate that the drug-treated (5 mg/kg memantine) sham-lesioned rats exhibited significantly impaired performance relative to the saline controls in terms of trials-to-criterion (P0.05). 2.5 mg/kg memantine administered 30 min before behavioral testing, did not affect performance in place learning task. 2.5 mg/kg and 5 mg/kg memantine administered before behavioral testing, did not improve performance in place learning task in MS electrolytic lesioned rats. Our experimental data support the interpretation that memantine does not produce intolerable side effects in human AD patients because it is being used at doses that are below the threshold for interacting with NMDA receptors.

Memantine is an NMDA receptor antagonist that has been recently approved in EU for the treatment of moderate to severe Alzheimer's disease. The previous studies have not allowed for the evaluation of the possible effects of this drug at therapeutic doses on different forms of memory. To address this question, we administered memantine to adult rats, using doses 2.5 or 5 mg/kg and evaluated the effects of these doses on open field activity and recognition memory. Memantine or saline was administered daily by intraperitoneal injection beginning on the day of behavioral testing and continuing 5 days. The main results of experiments are as follows: the memantine treatment produced a dose-related suppression of total ambulations. There was no significant impairment in detecting spatial and object novelty in the 2.5 mg/kg memantine treated rats. However, the 5 mg/kg intraperitoneal dose of memantine disrupted both recognition memory and locomotor behaviors. Our evaluation of memantine reveals that at doses lower than are required for neuroprotection disrupt memory. This raises the possibility that the beneficial effects seen in AD patients may be attributable to the interaction of memantine with other transmitter systems.

The aim of the present study was to investigate the effects of excitotoxic lesions of the dorsal CA1 region of the hippocampus on acquisition of a place and cue water maze task. The ibotenic acid injections into CA1 produced removal of the pyramidal cells in CA1, while saving most of the pyramidal cells in CA3 and granule cells in DG intact. In conditions of visible platform training trials, differences in the platform reaching latency between the animals of different groups, were not found. When testing was performed in conditions of submerged platform, the latency of the platform finding was significantly increased (P0.05). This fact certifies for deficit of the place learning strategy in the CA1-lesioned rats. Decreased place-bias in CA1-lesioned rats in hidden platform training trials compared to the sham-operated rats was significant, but in testing trials when required to choose between the spatial location they had learned and the visible platform in a new location majority of them swam first to the old spatial location. Decreased place-bias in CA1-lesioned rats compared to the sham-operated rats was not significant. We suggest that spatial learning deficits observed after dorsal hippocampal lesions cannot be accounted solely to the loss of dorsal hippocampal CA1 region cells.

In order to investigate the possible involvement the DG in spatial and object recognition memory, we have opted for a non-associative task where no explicit reward was present. Colchicine was used for bilateral DG lesions for its well-known specificity for DG lesion. Colchicine-induced lesions produce severe damage in the granule cells of DG, while minimally affecting pyramidal cells in CA1 and CA3. The main results are as follows: The overall habituation to the familiar environment in DG lesioned rats was decreased than in sham operated rats. There was no significant impairment in detecting spatial novelty. Lesions of the DG did not affect the detection of a novel object placed in a familiar location. Considering both the impaired habituation and the generally intact detection of spatial changes, we suggest that exploratory activity in relation to the entire environment and to the particular objects is thought to be subserved by diverse nervous substrate, and testing in the given conditions allows for their differential estimation.

An overview is given on polymer electrolytes based on organo-functionalized polyphosphazenes and polysiloxanes. Chemical and electrochemical properties are discussed with respect to the synthesis, the choice of side groups and the goal of obtaining membranes and thin films that combine high ionic conductivity and mechanical stability. Electrochemical stability, concentration polarization and the role of transference numbers are discussed with respect to possible applications in lithium batteries. It is shown that the ionic conductivities of salt-in-polymer membranes without additives and plasticizers are limited to maximum conductivities around 10-4 S/cm. Nevertheless, a straightforward strategy based on additives can increase the conductivities to at least 10-3 S/cm and maybe further. In this context, the future role of polymers for safe, alternative electrolytes in lithium batteries will benefit from concepts based on polymeric gels, composites and hybrid materials. Presently developed polymer electrolytes with oligoether sidechains are electrochemically stable in the potential range 0-4.5V (vs. Li/Li+ reference). © by Oldenbourg Wissenschaftsverlag, München. Deutsche Forschungsgemeinschaft --This work was part of the research program A2 within the collaborative research center “SFB 458”, funded by the Deutsche Forschungsgemeinschaft. We thank K. Funke, R. Banhatti, H. Eckert, C. Cramer-Kellers, M. Schönhoff, A. Heuer, R. Pöttgen, B. Krebs, T. Nilges, N. Stolwijk, L. van Wüllen and D. Wilmer for helpful discussions, thanks also to all colleagues in the SFB 458 for the excellent collaboration. Finally, we would like to acknowledge the collaboration with D. Richter, R. Zorn, and W. Pyckhout-Hintzen on SANS experiments in Jülich, the collaboration with S. Passerini and M. Winter regarding the electrochemical analysis of polymer electrolytes in lithium ion cells, and we thank H. Gores (University Regensburg) and G. Röschenthaler (Jacobs University Bremen) for preparing and making available a number of novel lithium salts.

The aim of this study was to investigate the modulation of the cognitive function by the cholinergic cells of the nucleus basalis magnocellularis (NBM) and was designed to investigate the role of the NBM cholinergic cells in learning and memory using the immunotoxin 192 IgG-saporin to produce selective lesions of cholinergic NBM neurons. A total of 16 male outbred albino rats were used in the present study to investigate the ability of sham-operated and NBM immunotoxin lesioned rats to learn the location of a visible, as well as submerged platform in a water maze. Examination of the AChE stained sections showed that after injections of 192 IgG saporin into the NBM, animals exhibited significantly less AChE staining in PFC as compared to sections obtained from sham-operated animals. An overview of the data from both competition trials for each group show that the sham-operated rats in 13 trials out of 16 competition test trial used place strategy and NBM-lesioned ones used this strategy in 6 trials. Decreased place-bias in NBM-lesioned rats compared to the sham-operated rats was significant (t(d )= 2,42, P0.02).The data obtained in the sham-operated and NBM-lesioned animals in the present study, demonstrate that the choice of strategy in the competition trial is related to performance during training: the rats exhibiting cue strategy (NBM-lesioned) on the competition trial had significantly worse performance during hidden platform training than those (sham-operated) exhibiting a place strategy. These findings suggest that the NBM is essential for accurate spatial learning and suggest its role in processing information about the spatial environment, but also we can propose, that the behavioral deficits described in the present study is nonmnemonic, possibly caused by deficit in attentional function.

This experiment investigated the ability of sham-operated and medial septal (MS) damaged rats to learn the location of a visible, as well as submerged platform in a water maze. The rats' responses on the competition test were classified as either cue or place, based on the swim path for those trials. Sham-operated rats acquired both the visible and hidden platform versions of the task, but when required to choose between the spatial location they had learned and the visible platform in a new location majority of them swam first to the old spatial location. The MS damaged rats acquired the visible platform version of the water maze task but failed to learn the platform's location in space. When the visible platform was moved to a new location they often swam directly to it. Sham-operated rats identified as place responders had significantly more accurate searches during hidden platform training, providing additional evidence of their effective use of a place learning strategy than MS is damaged. These findings suggest that in the absence of a septohippocampal functional system behaviour was not affected by spatial information and responding to local reinforced cues was enhanced. These data add to a growing literature demonstrating that the septo-hippocampal system is essential for accurate spatial learning and suggest its role in processing information about the spatial environment.