187 research outputs found
Investigation of a CTS solar cell test patch under simulated geomagnetic substorm charging conditions
The CTS solar array technology experiment which consists of a solar cell test patch on the Kapton-substrate solar array and the appertaining electronics unit has been operating in geostationary orbit for nearly 1 year without any malfunction although it is expected to be strongly influenced by charging effects on the array surface. The results of a post-launch test program show that the experiment would not survive a discharge due to electrostatic charging in the test patch area. In a simulated substorm, environment discharges were obtained only below a temperature threshold of about 30 C. With solar illumination, this threshold is reduced below 0 C
Pleyotropic antiaggregant effects of an innovative antiarrhythmic of class III SS-68, an indole derivative
A new indole derivative with the lab code-number SS-68 demonstrates a significant antiarrhythmic (anti-fibrillation) activity associated with the predominant influence on potassium and calcium conductivity of cardiomyocytes plasmalemmas. The preliminary data give evidence of SS-68 possessing an antiaggregant activity. The influence of SS-68 on the platelet formation stage of hemostasis was determined by assessment of the anti-platelet effect (measuring platelet aggregation with Born/ O’Brien method), the dynamics of intracellular concentration of calcium ions in platelets was studied with FURA-2/АМ fluorescent prob
Distribution of cocaine- and amphetamine-regulated transcript in the hippocampal formation of the guinea pig and domestic pig
This study provides a detailed description concerning the distribution of cocaineand
amphetamine-regulated transcript (CART) subunits - CART61-102 and
rhCART28-116 - in the hippocampal formation (HF) of the guinea pig and domestic
pig, focussing on the dentate gyrus (DG) and hippocampus proper (HP).
Although in both studied species CART-immunoreactive (CART-IR) neuronal somata
and processes were present generally in the same layers, some species-specific
differences were still found. In the granular layer (GL) of both species, the ovalshaped
neurons and some thick varicose fibres were encountered. In the guinea
pig there was an immunoreactive “band of dots”, probably representing crosssectioned
terminals within the DG molecular layer (MOL), whereas in the domestic
pig, some varicose fibres were detected, thus suggesting a different orientation of,
at least, some nerve terminals. Furthermore, some CART-positive cells and fibres
were observed in the hilus (HL) of the guinea pig, whereas in the analogical part of
the domestic pig only nerve terminals were labelled.
In both species, in the pyramidal layer (PL) of the hippocampus proper, CART-IR triangular somata were observed in the CA3 sector, as well as some positive
processes in MOL; however, a few immunoreactive perikarya were found only
in the CA1 sector of the guinea pig. As regards the localization patterns of two
isoforms of CART in the guinea pig, both peptide fragments were present simultaneously
in each of the labelled neurons or fibres, whereas in the domestic
pig three types of fibres may be distinguished within the area of the DG. In
the hilus and MOL of the dentate gyrus, there were fibres expressing both
isoforms of CART in their whole length (fibres of the first type). Fibres of the
second type (in GL) coexpressed both peptides only on their short segments,
and the last ones (in MOL) expressed solely rhCART28-116.
These results indicate that the distribution of the two CART isoforms are specifically
related, thus the relationship between the two CART isoforms may imply
different metabolic profiles of CART-expressing neurons
Part I
The problem of heart rhythm disturbances is one of the most urgent topics of modern cardiology. According to the currently available concepts, 1,2- and 1,3-disubstituted aminoindole derivatives, which compound 2-phenyl-1-(3-pyrrolidin-1-il-propyl)-1H-indole hydrochloride (SS-68) belongs to, are a promising chemical group in terms of their cardio-pharmacological activit
Anticholinergic activity and pharmacokinetic parameters of agent SS-68 with properties of class III antiarrhythmic drugs
It was shown that the indole derivate SS-68 (50 and 250 μg/kg intravenous) in acute experiments on cats with neurogenic atrial fibrillation (AF) has a dose-dependent antiarrhythmic action which is associated with the neurotropic influence of this substance, since the suppression of the AF coincides with its anticholinergic effect observed for more than 2 hours, but cardiotropic action at this time was not observed. High antiarrhythmic activity of SS-68 to neurogenic AF may be due to the IKAch inhibition and blockade of M2-cholinergic receptor
The neuronal structure of the preoptic area in the mole and the rabbit: Golgi and Nissl studies
The present studies were carried out on the brains of the adult mole and rabbit.
The preparations were made by means of the Golgi technique and the Nissl
method. Two types of neurons were distinguished in the preoptic area (POA) of
both species: bipolar and multipolar. The bipolar neurons have oval, fusiform or
round perikarya and two dendritic trunks arising from the opposite poles of the
cell body. The dendrites bifurcate once or twice. The dendritic branches have
swellings, single spine-like and filiform processes. The multipolar neurons usually
have triangular and quadrangular perikarya and from 3 to 5 dendritic trunks.
The dendrites of the mole neurons branch sparsely, whereas the dendrites of
the rabbit neurons display 2 or 3 divisions. On the dendritic branches varicosities
and different protuberances were observed. The general morphology of the
bipolar and multipolar neurons is similar in the mammals studied, although the
neurons of the rabbit POA display a more complicated structure. Their dendritic
branches show more divisions and possess more swellings and different processes
than the dendrites of the neurons of the mole POA. Furthermore, of the
multipolar neurons only the dendrites in POA of the rabbit were observed to
have a rosary-like beaded appearance
A morphometric comparative study of the lateral geniculate body in selected placental mammals: the common shrew, the bank vole, the rabbit, and the fox
The lateral geniculate body (LGN) was morphometrically examined and compared
in representatives of four mammalian orders (Insectivora, Rodentia, Lagomorpha,
and Carnivora). In each studied species, the lateral geniculate body
was divided into two distinct parts: the dorsal nucleus (LGNd) and the ventral
nucleus (LGNv). The lateral geniculate body of the common shrew and the
bank vole are very similar in appearance and nuclear pattern. The dorsal and
ventral nuclei of these two species also have the most similar statistical characteristics.
The lateral geniculate body of the fox has the most complicated morphology
and multilayered structure. A significant disproportion was observed
between the sizes of both geniculate nuclei in the fox, where the dorsal nucleus
definitely surpassed the ventral nucleus in terms of volume. With the exception
of the fox, the neuronal density of the LGN nuclei was negatively correlated
with the volumes of the LGN. The mean neuronal size of the LGNd and
LGNv, which was the resultant of the length, width, area, and circumference
of the soma, grew correlatively to the volumes of these nuclei. In all examined
species, somas of the LGNd neurons are distinctly larger and have more similar
shapes than the LGNv perikarya. In addition, the numerical density of neurons
in the ventral nucleus is significantly higher than in the dorsal nucleus. All these
morphometric parameters clearly differentiate the LGNd from the LGNv
The nerve cells of the neostriatum in the common shrew (Sorex araneus) and bank vole (Clethrionomys glareolus): a Golgi comparative study
The studies were carried out on 12 brains derived from adult representatives of two mammalian orders, Insectivora and Rodentia. The neostriatum was compared in the common shrew (Sorex araneus) and bank vole (Clethrionomys glareolus).
Three main types of striatal neuron were distinguished in the common shrew and five types of neurons in the bank vole. The fifth type of bank vole neurons was additionally divided into two subtypes with respect to dendritic pattern
The neuronal structure of the dorsal nucleus of the lateral geniculate body in the common shrew (Sorex araneus) and the bank vole (Clethrionomys glareolus): Golgi and Nissl studies
The topography and neuronal structure of the dorsal nucleus of the lateral geniculate
body (GLd) of the common shrew and the bank vole are similar. The
lateral geniculate body of both the species examined has a homogeneous structure
and no observable cytoarchitectonic lamination. On the basis of the shape
of the dendritic arbours as well as the pattern of dendritic arborisations the
following two types of neurons were distinguished. Type I “bushy” neurons that
have multipolar or round perikarya (common shrew perikarya 9–12 µm, bank
vole perikarya 10–13 µm), with 4–6 short thick dendritic trunks that subdivide
into many bush-like branches. The dendritic trunks are smooth, in contrast to
the distal branches, which are covered with numerous spine-like protrusions of
different lengths and forms. An axon emerges from the soma, sometimes very
close to one of the primary dendrites. The type I neurons are typically projection
cells that send their axons to the primary visual cortex. These neurons predominate
in the GLd of both species. Type II neurons, which have an elongated
soma with primary dendrites arising from opposite poles of the perikaryon (common
shrew perikarya 8–10 µm, bank vole perikarya 9–11 µm). The dendritic
arbours of these cells are less extensive and their dendrites have fewer spines
than those of the type I neurons. Axons were seldom observed. The type II
neurons are presumably interneurons and are definitely less numerous than the
type I neurons
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