Study of a genetic collection of strawberry (Fragaria L.) for resistance to powdery mildew.

Powdery mildew (Sphaerotheca macularis Mag. (syn. Podosphaera aphanis Wallr.

Polymorphism of the FaOMT and FaFAD1 genes for fruit flavor volatiles in strawberry varieties and wild species from the genetic collection of the Michurin Federal Research Center.

Fruit aroma is an important consumer attribute of strawberry varieties. The key volatile compounds of the aromatic complex of strawberry fruit are mesifurane (fruity and caramel aromas) and γ-decalactone (fruity, sweet, or peachy aroma). The mesifurane content in strawberry fruit is controlled by the FaOMT gene, which is mapped to the distal region of the long arm of chromosome VII-F.

[Exosomes secretion and autophagy in long-term protection of neurons from excitotoxic damage].

In the model of induced neuronal resistance to the toxic effect of glutamate (deprivation of trophic factors), exosome secretion is demonstrated. Exosomes are secreted at the development of resistance during deprivation and at the first 24 h after preconditioning, as was shown by dot blot of extracellular fluid using anti-CD63 antibody. The autophagy inhibitor bafilomycin (0.

[Peptide drug cortexin inhibits brain caspase-8].

Cortexin, a drug containing hydrolyzed brain peptides, has long been used in clinics, but the mechanisms of its action remain obscure. We have hypothesized that cortexin-related neuroprotection is associated with the ability of the drug to inhibit brain proteases. Cortexin effectively inhibited brain caspase-8, while its effects on caspase-1, -3, -9, cathepsin B and calpain were much less pronounced or absent.

[Trophic factors deprivation induces long-term protection of neurons against excitotoxic damage].

One of the strategies to induce tolerance of neurons to toxic injury is preconditioning. Preconditioning is caused by a weak damage of cells, which become more resistant to subsequent, more severe damage. We found that preconditioning by deprivation of trophic factors, or deprivation of trophic factor and glucose effectively protects neurons against subsequent toxic effects of glutamate.

A secreted caspase-3-substrate-cleaving activity at low pH belongs to cathepsin B: a study on primary brain cell cultures.

The cysteine proteases caspase-3 and cathepsins are involved in both neuronal plasticity and neuropathology. Using primary neuroglial and glial cerebellar cultures, the pH dependence of cleavage of a synthetic caspase-3 substrate, Ac-DEVD-AMC, was studied. At acidic pH, cathepsin B cleaved Ac-DEVD, this activity being significantly higher than that of caspase-3 at pH 7.

Antioxidant and neuroprotective properties of N-docosahexaenoyl dopamine.

N-Docosahexaenoyl dopamine exhibited antioxidant activity in the test with a stable oxygen radical galvinoxyl. This compound produced a dose-dependent protective effect on cultured granular cells from rat cerebellum under conditions of oxidative stress. N-Docosahexaenoyl dopamine decelerated the development of symptoms of Parkinson's disease in mice receiving neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.

Central administration of a caspase inhibitor impairs shuttle-box performance in rats.

Recent studies suggest that caspase-3-mediated mechanisms are essential for neuronal plasticity. N-benzyloxycarbonyl-Asp(OMe)-Glu(OMe)-Val- Asp(OMe)-fluoromethyl ketone (z-DEVD-fmk), a caspase inhibitor with predominant specificity toward caspase-3, has been shown to block long-term potentiation in hippocampal slices. Intrahippocampal infusion of a caspase-3 inhibitor to rats has been shown to significantly impair spatial memory in the water maze.

Characteristics of the development of the sensorimotor cortex in rats aged 7-8 days in roller cultures of free-floating brain slices.

The development and formation of the neuronal architectonics of organotypic structures of the sensorimotor cortex in rats aged 7-8 days were studied in roller cultures. Free-floating slices were cultured for 2-3 weeks. Serial paraffin sections of cultured tissue were stained with fast cresyl violet as described by Nissl.

Direct nn-Scattering Measurement With the Pulsed Reactor YAGUAR.

Although crucial for resolving the issue of charge symmetry in the nuclear force, direct measurement of nn-scattering by colliding free neutrons has never been performed. At present the Russian pulsed reactor YAGUAR is the best neutron source for performing such a measurement. It has a through channel where the neutron moderator is installed.

Roller organotypic cultures of postnatal rat retina.

Floating retinal sections from 7-12-day-old rats form ball-shaped retinal bodies during roller culturing. Histological studies of serial sections of retinal bodies showed that their outer surface is formed by the retina completely retaining organotypic cytoarchitectonics. Some retinal bodies have laminar structure consisting of several layers of the retina.

[Developmental characteristics of the sensorimotor cortex of 7-8 days old rats in the roller cultures of free-floating brain slices].

Development and formation of neuronal architectonic of organotypic structures of sensomotor cortex of 7-8-day-old rats was studied in roller cultures. Free-floating cortical slices were cultured for 2-3 weeks. Serial paraffin sections of cultured tissue were stained with cresyl violet fast using Nissl's method.

Protective effect of Biolan during ischemic damages to cultured cerebellar granular cells.

Biolan containing carnosine and delta sleep-inducing peptide produced a protective effect on cerebellar granular cells from 7-day-old rats exposed in culture to ischemia (oxygen and glucose deprivation) and cytotoxic influence of glutamate. These results indicate that Biolan holds much promise for correction of ischemic brain damages in clinical practice.

[Ischemic injury of the ultrastructure of neurons in organotypic hippocampal tissue culture].

An ultrastructural study of organotypic hippocampal explants subjected to the effect of ischemia for 30 min followed by a period of reoxygenation lasting for 20-24 hours, was performed. The data obtained indicate that ischemic injury of area CA1 neurons develops mainly as a necrosis. In addition, some neurons along with necrotic changes, demonstrate some signs of apoptosis, suggesting that the execution of its program may accompany these changes, thus leading the cells to the state of so-called apoptotic-necrotic continuum.

Histogenesis of hippocampus and neocortex isolated from postnatal rats in organotypic roller tube cultures of floating brain sections.

Floating sections of the hippocampus and neocortex isolated from 6-10-day-old rats retained their spatial cell organization after 2-week roller-tube culturing. Cell structure in CA1, Ca2, and CA3 fields, polymorphic layer of the fascia dentata and its medial and lateral limbs were revealed in sections of the dorsal hippocampus. In neocortical sections, cortical neurons and subcortical structure were preserved, however, some cortical fragments changed their configuration and formed spherical structures, where cortical neurons were located in the external layer without forming typical of neocortex 6-layer structure.

[Ultrastructural plasticity in the hippocampus organotypic tissue culture].

Hippocampal cross sections of 7-9 day old rats were explanted onto semipermeable microporous membranes for 14-16 days followed by electron microscopic investigation. Besides the structures typical for adult hippocampus in vivo, substantial ultrastructural signs of metabolism and synaptic connections in explants were revealed: redistribution of polysomes and cisterns of granular endoplasmic reticulum, numerous pinocytotic invaginations, growth cones, somatic filopods, dotted (perforated) contacts, new formation of synapses and vacant postsynaptic sites. The data obtained indicate the active compensatory processes of plasticity, which ensure the maintenance of structure and function of hippocampal tissue in vitro.

Effect of a prolonged glutamate challenge on plasmalemmal calcium permeability in mammalian central neurones. Mn2+ as a tool to study calcium influx pathways.

The rate of Mn(2+)-induced fluorescence quenching (RFQ) was used as a relative measure of plasma membrane Ca2+ permeability (PCa) in fura-2-loaded cultured hippocampal neurons and cerebellar granule cells during and after protracted (15-30 min) glutamate (GLU) treatment. Some limitations of this method were evaluated using a kinetic model of a competitive binding of Mn2+ and Ca2+ to fura-2 in the cell. In parallel experiment a contribution of Ca2+ influx to the cytoplasmic Ca2+ ([Ca2+]i) was repeatedly examined during and following a prolonged GLU challenge by short-duration "low-Ca2+ trials" (50 microM EGTA) and by measurements of 45Ca2+ uptake.

Hypoxic and posthypoxic neuronal injury in hippocampal cell culture: attenuation by lipophylic antioxidant U-18 and superoxide dismutase.

The neuroprotective effects of synthesized lipophylic antioxidant from hindered phenol class (U-18) and hydrophylic antioxidative enzyme superoxide dismutase (SOD) were tested on long-term mouse hippocampal cell cultures exposed to hypoxia/reoxygenation. The application of U-18 to the cultures during 6-8 hr hypoxia followed by 16-18 hr reoxygenation in the absence of antioxidant significantly reduced neuronal death. Thus, lipophylic free radical scavenger may exert a delayed neuroprotective effect, probably owing to persistent incorporation into phospholipid membranes and prevention of their lipid peroxidation by means of prolonged intramembranous free radical quenching.

[The role of posthypoxia reoxygenation in the destruction of cultured hippocampal neurons].

A comparative quantitative analysis of neuronal death was performed on mice hippocampal cell cultures, which were subjected to hypoxia only or to hypoxia with subsequent reoxygenation during equal time. It was shown that the number of dead neurons significantly increased after 5-7 hs hypoxia followed by 3 hs reoxygenation period, comparatively with neuronal death observed after 8-10 hs hypoxia without subsequent reoxygenation. These results demonstrate that neurodestructive processes initiated by hypoxia develop more intensively during the posthypoxic reoxygenation than during the equal time of hypoxia and suggest the role of free radical and peroxide compound formation in neuronal death after renewal of oxygen access to nerve cells.

[Cultivation of reaggregated brain cells in rapidly rotating mini-rollers].

An original method of cultivation of reaggregated brain cells with the aid of high-speed portable mini-rollers is described. The mini-roller consists of parallel rollers and an electric motor rotating the flasks at a speed of 60 to 70 rpm. The Moscona technique was used for preparing brain cell suspensions.