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T Szabados

Publications and source records attributed to T Szabados.

13 recordsLinked to original sources

Comparison of anticonvulsive and acute neuroprotective activity of three 2,3-benzodiazepine compounds, GYKI 52466, GYKI 53405, and GYKI 53655.

GYKI 52466 [1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine], a non-competitive AMPA [alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate] and kainate receptor antagonist and its two analogues, GYKI 53405 [1-(4-aminophenyl)-3-acetyl-4-methyl-3,4-dihydro-7,8-methylenedioxy-5H-2,3-benzodiazepine] and GYKI 53655 [1-(4-aminophenyl)-3-methylcarbamyl-4-methyl-3,4-dihydro-7,8-methylenedioxy-5H-2,3-benzodiazepine] were investigated in two seizure models and in MgCl2 induced global cerebral ischaemia, as an acute neuroprotective model. The ED(50) values of GYKI 52466 for suppression of the tonic and clonic phases of sound-induced seizures were 3.6 and 4.3 mg/kg, respectively. The corresponding data for GYKI 53405 were 1.1 and 3.1 mg/kg, while ED(50) values of GYKI 53655 were 1.3 and 2.0 mg/kg, respectively. The inhibition of seizure evoked by maximal electroshock was also found to be remarkable: the ED(50) values of GYKI 52466 and its two analogues were 6.9, 2.6, and 2.2 mg/kg, respectively. All compounds prolonged the survival times in MgCl2 induced global cerebral ischaemia test in a dose-dependent fashion, with PD(50) (dose of 50% prolongation) values of 24.1, 8.3, and 8.2 mg/kg intraperitoneal, respectively. In audiogenic seizure model the duration of anticonvulsant action of 10 mg/kg GYKI 52466 and 5 mg/kg GYKI 53405, GYKI 53655 were examined, too. The effect of GYKI 52466 decreased to 50% after 2 h, while the analogues showed more than 80% seizure suppression 3 h after treatment. After 6 h the effect of GYKI 53655 decreased to zero, while the effect of GYKI 52466, remained on the 50% level.

Acoustic Stimulation↗

Some aspects of complementarity in the immune system. A bird's eye view.

The burden of this paper is the suggestion that the defence capacity of the immune system is rather limited. It cannot stand in readiness to deal with a practically endless diversity and abundance of microbes. In contrast to conventional thinking the current model proposes: (1) The core idea that cells of the immune system are basically and constantly interconnected with host cells (e.g., through TCR-MHC interactions) and that foreign antigens (peptides) may tend to obstruct such interactions. Peptides presented during a viral infection typically decrease complementarity between the structures that are the products of the major histocompatibility complex (MHC) genes (or other genes related to it) and T cells. The altered MHC profile exposes infected cells to a polyclonal immune attack from other T cells such that tissue destruction occurs in an allograft rejection-like fashion. This may explain why a substantial portion of T cell numbers is activated when only a small number of specific T cells is 'obstructed' from functioning by the presence of nonself peptides. (2) Phagocytes 'see' targets even in a non-immune host because complement distribution associated with polyreactive natural antibodies magnifies sensitization differences between pathogens and host cells. (3) There is only a probability that hypermutation will successfully change the genome in some B cell clones to produce high affinity antibodies that prevent the re-infection of the host by the same pathogen, but cannot conquer primary infections. (4) The history of the development of the immune responses suggests that during prolonged interaction between host and microbes in our natural habitat, carried on over many generations, the adaptive antibody population may facilitate the evolution of the natural antibody repertoire. The model predicts that microbes, which are not a part of the local environment, may invade the organism without significant resistance. The model is discussed in various interactions for survival in the context of infection and tumorigenicity.

Adaptation, Physiological↗

Effect of fumaric acid, its dimethylester, and topical antipsoriatic drugs on epidermal differentiation in the mouse tail model.

Fumaric acid, fumaric acid dimethylester, and the dithranol derivative C4-lactone were studied in the mouse tail test to evaluate their effects on epidermal cell differentiation compared with other topical antipsoriatic drugs, such as betamethasone, calcipotriol, and dithranol. Mouse tails were treated for 2 weeks and longitudinal histological sections prepared of the tail skin. The length of the orthokeratotic regions (stratum granulosum) was measured on 10 sequential scales per tail and expressed as percentage of the full length of the scale. In addition, epidermal thickness was measured and the efficacy of the various compounds evaluated. In comparison to 2% salicylic acid ointment, all tested compounds except fumaric acid significantly (p < or = 0.05) increased the proportion of the orthokeratotic region. C4-lactone and calcipotriol were less effective than dithranol, fumaric acid dimethylester only moderately influenced cell differentiation, and betamethasone showed the least potent effect. Dithranol was the most potent substance inducing orthokeratosis without increasing epidermal thickness.

Administration, Topical↗

Ketone compound smelling ability: study in Hungarian twins.

On the basis of their earlier experiments the authors assumed that the ability to recognize the smell of two ketone compounds, acetone and methylethylketone (MEK), might be determined genetically. In the present work of smelling test was performed in adult Hungarian twins, 61 like sexed DZ pairs and 87 MZ pairs. No connection was found between twin zygosity and intra-pair concordance for MEK, while in the case of acetone smelling some connection may exist. A highly significant correlation was found between the smelling ability to acetone and MEK. Females seemed to be better smellers than males. Comparing the taste perception for PTC to the smell perception for acetone the supposition of a possible genetic linkage between the two traits, put forward by other authors, could not definitely be confirmed.

Acetone↗