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Biomedical subjects

G Somogyi

Publications and source records attributed to G Somogyi.

At least 37 records · Page 2Linked to original sources
PubMed1989

Synthesis of dibenzodioxazocines and their effects on cholinesterases and muscarinic cholinergic receptors.

A new family of tricyclic compounds, the dibenzodioxazocines were synthesized. These compounds were the following: 2-chloro-12-(2-piperidino-ethyl)-dibenzo d,g 1,3,6 dioxazocine hydrochloride: EGYT-2347, 2-chloro-12-(3-dimethylamino-2-methyl-propyl)-dibenzo [d,g] [1,3,6]-dibenzodioxazocine hydrochloride: EGYT-2509, 2-chloro-12-(3-dimethylamino-propyl)-dibenzo [d,g] [1,3,6] dioxazocine-maleate: EGYT-2474 and 2-chloro-12-2-(4-methyl-piperazino)-ethyl-dibenzo [d,g] [1,3,6]-dioxazocine-dihydrochloride: EGYT-2541. These compounds are inhibitors of both butyryl- and acetylcholinesterase to and they exhibited relatively good anticholinergic properties in receptor binding experiments. The most selective inhibitor of butyrylcholinesterase is the compound EGYT-2347 (Ki = 1.5 x 10(-7) M) which strongly binds to rat brain muscarinic cholinergic receptor (KD = 4.1 x 10(-8) M).

Animals↗
PubMed1989

Effect of choline esters and oleic acid on the penetration of acyclovir, estradiol, hydrocortisone, nitroglycerin, retinoic acid and trifluorothymidine across hairless mouse skin in vitro.

Five choline esters, lauroylcholine, myristoylcholine, palmitoylcholine, stearoylcholine and oleoylcholine, were evaluated as skin penetration enhancers by testing their effects on the penetration of six drugs, acyclovir, 17 beta-estradiol, hydrocortisone, nitroglycerin, all-trans-retinoic acid and trifluorothymidine, across hairless mouse skin in vitro and comparing the results to those obtained with oleic acid. The results show that the transdermal delivery of the drugs tested from propylene glycol vehicle systems, can be significantly increased by adding small amounts of choline esters and/or oleic acid to the vehicle. Lauroylcholine was a better enhancer than oleic acid for the transdermal delivery of 17 beta-estradiol and, in mixtures, lauroylcholine and oleic acid acted as synergists giving larger enhancement of the transdermal delivery of nitroglycerin and acyclovir than when used separately.

Acyclovir↗
PubMed1988

A suicide with neuromuscular blocker.

We experienced an autopsy case in which a 29-year-old woman committed suicide by parenteral application of a neuromuscular blocker combined with thiobarbital. These medicines were easily accessible to the victim who was an anesthesiologist in a hospital. Paralyzing the respiratory muscles the usual dose of neuromuscular blockers can cause death unless a breathing apparatus is used. Unusual medicines given in small doses are difficult to detect in the autopsy materials. In our case in the course of forensic investigation we successfully identified the traces of a neuromuscular blocker by mass spectrometry.

Adult↗
PubMed1987

Study of transport processes in soils and plants by microautoradiographic and radioabsorption methods.

The concentration profiles of lead and boron in carrot root and potato tuber were determined at various diffusion times by microradiographic method. The order of magnitude of the diffusion coefficient of lead ions and borate- or tetraborate ions was 10-13 m2s-1 and 10-11 m2s-1, respectively. The transport process of nutrients, leaf-manures and plant-protecting agents in plants was investigated by radioabsorption method. The effect of complex-forming agents on the absorption of nutrients and leaf-manure compositions was also examined. The influence of the pH of soils and complex-forming agents on the effective diffusion coefficients of nutritives was studied by means of the radioabsorption technique. In soils, the effective diffusion coefficient of the nutrients was found to change in the region 10-16-10-10 m2s-1. The data of the measurements give valuable information about the transport processes in plants and soils, allowing control and influence thereof.

Absorption↗
PubMed1985

Numerical estimation of gamma-aminobutyric acid (GABA)-containing neurons in three thalamic nuclei of the cat: direct GABA immunocytochemistry.

The percentage of neurons that are immunoreactive for the inhibitory neurotransmitter, gamma-aminobutyric acid (GABA) was determined within: (1) the lateral geniculate nucleus (LGN), (2) the ventrobasal complex (VB) and (3) the antero-ventral nucleus (AV) of the thalamus in the cat. An antiserum to GABA was used to stain GABA-containing perikarya in 1.0 micrometer thick Araldite-embedded sections. Immunostained somata in all three nuclei were invariably smaller than the immuno-negative nerve cells. 27% of all neurons in the LGN, 33% in the VB and 25% in the AV were immunoreactive for GABA.

Animals↗
PubMed1983

Neuronal and synaptic arrangements of the lateral geniculate nucleus in night-active primates.

The lateral geniculate nucleus (LGN) of Aotus trivirgatus and Nycticebus coucang shows two types of neurons at the ultrastructural level: a large thalamo-cortical relay neuron (TCR) and a small neuron of Golgi type II, which is considered to be an interneuron. The interneuron contains small aggregations of synaptic vesicles in the perikaryon adjacent to the cell membrane in synaptic contact to a TCR neuron. Only in the perikaryon of the interneurons can cilia have their origin. After unilateral enucleation, neurofilamentous or dark degenerations of large boutons with round vesicles (type RL) occur in the outer layers of the contralateral LGN and in the inner layers of the ipsilateral LGN. The optic terminals establish synaptic contacts in the glomerulus with dendritic spines of the TCR neurons and with presynaptic dendrites (F2) of interneurons.

Animals↗
PubMed1983

Quantitative histological study on the thalamic ventro-basal complex of the cat. Numerical aspects of the transfer from medial lemniscal fibers to cortical relay.

A quantitative analysis was carried out on the thalamic ventrobasal (VB) complex of the cat. The following numerical and metrical parameters of the neuronal elements (cells and fibers) were determined: 1. Volume of nucleus: 27.38 mm3 2. Total number of neurons: 243,000 3. Total number of fibers of medial lemniscus: 26,000 4. Volume of arborization space of one lemniscal fiber: 2.26 X 10(6) micrometers 3. Numerical data of relay neurons and lemniscal fibers and their relations as basic factors in the estimation of the degree of divergence and convergence of lemniscal input were calculated and compared. It was found that the probable degree of convergence is four-fold (1-4) and of divergence 27-fold (1-27) with regard to the relationship of fibers and cells in the VB. The quantitative data obtained in the VB and our considerations on convergence and divergence were compared with analogous values obtained for the lateral geniculate body LGB. The differences between the two sensory relay nuclei reflect differences in their modes of impulse transmission.

Animals↗
PubMed1982

[Fatal intoxications in Debrecen. Analysis of the cases from 1958 to 1981 (author's transl)].

In this report the toxicologic material obtained since 1958 in our institute has been evaluated. Of the 15,144 postmortem examinations, 997 toxicologic examinations have been carried out. In addition, 739 clinical cases have been studied during this period. There has been a monotonous increase in the number of toxicologic cases up to now. The number of cases is doubled during a 10-year period. Barbiturates are the main type of intoxicating agents found, but there is a rapid increase in the use of other drugs in the material studied. The use of nicotine is steadily decreasing but there is an increasing number of toxicologic cases in connection with the use of other plant protectives. The evaluation of toxicologic cases involving alcohol will be reported elsewhere.

Humans↗
PubMed1982

Neuronal and synaptic organization of the lateral geniculate nucleus of the tree shrew, Tupaia glis.

The ultrastructural study of the lateral geniculate nucleus (LGN) of the tree shrew (Tupaia glis) revealed two types of neurons: (1) a large thalamocortical relay cell (TCR), which may bear cilia, and (2) a small Golgi type-II interneuron (IN) with an invaginated nucleus. The narrow rim of pale cytoplasm of the IN contains fewer lysosomes and fewer Nissl bodies than the cytoplasm of the TCR. The IN perikarya, which in some cases establish somatosomatic contacts, frequently contain flattened or pleomorphic synaptic vesicles. The ratio of TCR to IN is 3:1. Three types of axon terminals were observed in the LGN. Two of them contain round synaptic vesicles but differ in size. The large RL boutons undergo dark degeneration after enucleation; they are the terminals of retino-geniculate fibers. The smaller RS boutons show dark degeneration after ablation of the visual cortex; they are the terminals of the cortico-geniculate fibers. The third type of bouton (F1) does not degenerate after either intervention. The boutons of this type are filled with flattened vesicles and are believed to be intrageniculate terminals. F2-profiles were interpreted as presynaptic dendrites of the IN. The characteristic synaptic glomeruli found in the LGN contain in their center an optic terminal. These optic terminals establish synaptic contacts with dendrites or spine-like dendritic protrusions of TCRs as well as with presynaptic dendrites. Synaptic triads were also seen. The distribution of the individual types of synaptic contacts in layers 3 and 4 were determined. Layer 4 contains only one third of the retino-geniculate synapses and of the synaptic contacts of F1-terminals.

Animals↗
PubMed1979

A combined horseradish peroxidase and Golgi study on the afferent connections of the ventrobasal complex of the thalamus in the cat.

Afferent connections to the ventrobasal complex (VB) of the thalamus were studied by means of retrograde transport of horseradish peroxidase (HRP) and by the Golgi-method. After HRP-injection into the VB, peroxidase-positive cells were observed contralaterally in the dorsal column nuclei (DCN), in the trigeminal nuclei and in the lateral cervical nucleus (LCN), and ipsilaterally in the somatosensoty I (SI) and II (SII) cortical areas. Labeled cells of different shape and size were compared with neurons impregnated by the Golgi-technique. On tn size and shape even within one region and that they correspond to the relay or efferent neurons observed in the Golgi-material.

Animals↗
PubMed1979

Types of thalamo-cortical relay neurons in the anteroventral nucleus of the cat. A combined horseradish peroxidase--Golgi study.

Neurons displaying a thalamo-cortical projection were marked by means of the retrograde transport of horseradish peroxidase (HRP), and the labeled elements were compared with neurons impregnated by the Golgi technique. Injections of HRP into the posterior area of the limbic cortex resulted in its uptake by various anterior thalamic nuclei, especially the anteroventral nucleus. HRP-positive cells are characterized by their position, dendritic orientation, and the shape and size of their somata. On the basis of the combined HRP-and Golgi-analysis three different types of thalamo-cortical relay neurons can be distinguished.

Animals↗
PubMed1979

Interneurons: an electron microscopic study of the cat's hippocampal formation, II.

The ultrastructure of interneurons was studied in the cat and it was found to differ from that of the pyramidal and granule cells. The size, shape and topographic situation of the cell body of interneurons were the criteria for approaching their identification with the cells found in Golgi material. Some interneuron dendrites are also described. The varicose and spindle-shaped dendritic profiles belonging to interneurons are different in size. In Golgi material the interneurons have beaded (varicose) or spindle-shaped dendrites. The arrangement of synaptic terminals on the interneuron dendritic surface seems to be their characteristic feature.

Animals↗