In the research a prototype to record the activity of ensembles of
single neurons from the brains of freely moving rats has been developed. The
DT4 prototype has 16 inputs, weighs 10 g and is powered for over 4 hours by an
18 g battery. The DT4 digitizes signals at 24-bit resolution, allowing signals
as small as 10 mV to be resolved.
Each input is initially low-pass filtered (5,5 kHz) and digitized (12 kHz). The
digital signals are combined into a single data stream and the serialized data
are then transmitted to a remote DSP-based recording system via either an
optical fiber or 2.4 GHz radio channel.
Authors:Erzsébet Háznagy-Radnai, Szilvia Czigle and Imre Máthé
Species of the
subfamily of the family
species, do not contain much essential oil. The first stage of studying the volatile components of
species was characterization of
-hexane extracts by TLC, with sabinene, limonene, linalool, and β-caryophyllene as test materials. On the basis of these results we then studied the volatile compounds by use of GC-FID and GC-MS. By examination of the TLC plates, use of
retention indices, and MS library search we identified components of essential oil fractions obtained from
II. (L.) Trev.,
L. subsp. recta, and
L. (from Vácrátót) by vapor distillation in accordance with Hungarian Pharmacopoeia VII.
Most of the beneficial biological effects (e.g. neurosedative, antioxidant, and antimicrobial) of black horehound (
L.) are because of its phenylpropanoid glycoside content. A rapid TLC-densitometric method with acceptable accuracy has been established for quantitative analysis of the most characteristic components of black horehound. Experiments were performed to establish the optimum conditions for densitometric measurement and for storage of extracts. Practical application of the elaborated method is reported for five plant extracts.
Authors:Erzsébet Háznagy-Radnai, Szilvia Czigle, Gábor Janicsák and Imre Máthé
species contain iridoids, for example harpagide, acetylharpagide, aucubin, harpagoside, and ajugoside. The iridoid composition and content of leaves, stems, and inflorescences of ten
species have been compared by use of a TLC-densitometric method. Harpagoside, harpagide, and acetylharpagide proved to be the main iridoids in
(C. Koch.) Jalas I.,
L. No iridoids were detected in
Authors:Mária Báthori, Attila Hunyadi, Gábor Janicsák and Imre Máthé
Eleven mobile phases and three stationary phases have been investigated for TLC separation of a large number of ecdysteroids. Optimization of the chromatography was based on trial and error. Use of four mobile phases on three stationary phases enabled separation of all the ecdysteroids from each other in at least one system. The TLC behavior of ecdysteroids containing different numbers of hydroxyl groups, side-chain variations, and extra double bonds, and of positional isomers and stereoisomers, is reported and interpreted. Our method is suggested for screening plant extracts for ecdysteroids.
Authors:Enikő Tóth, Gábor Janicsák, Imre Máthé and Gerald Blunden
Different parts of three
B. nigra, B. hirsuta
) have been analyzed for phenylpropanoid content by means of a simple extraction technique and a newly established TLC-densitometric method. The compounds studied were verbascoside (VE), forsythoside B (FB), and caffeoyl-malic acid (CM). The largest amounts were detected in
- CM (0.30%) and VE (4.58%) in the leaves and FB (3.0%) in the roots, followed by
; the smallest amounts were found in
- 0.08% CM, 1.64% VE, and 0.91% FB in the leaves. The absence of caffeoylmalic acid was characteristic of the roots only.
, the common representative of the genus in Hungary, was chosen for thorough study of variation of phenylpropanoids during the vegetative period. Amounts of the phenylpropanoids increased during the main and secondary flowering periods in June (FB, 6.00%; VE, 8.50%; CM, 0.45% in the leaves) and September (FB, 3.80%; VE, 7.00%;, CM, 0.35% in the leaves).
Authors:Gábor Janicsák, Erzsébet Háznagy-Radnai, Rita Engel, Gerald Blunden and Imre Máthé
A thin-layer chromatographic (TLC)-densitometric method was used for the parallel quantification of rosmarinic acid (RA) and caffeic acid (CA) in crude extracts of Salvia species (Family Lamiaceae), obtained by ultrasonic extraction with 60% methanol. The densitometric measurement was performed in fluorescent mode as it has been published earlier. The applicability of the method has been investigated mainly from the viewpoint of the starting material. Questions are discussed like, what kind of factors should be taken into account, if the drugs are to be characterized, and how the RA and CA contents of samples vary in the plants are discussed. The drugs (plant material) show great differences due to the time of harvest, to the organ composition of drugs, and to the extraction and storage conditions of the stock-solutions prepared from them. The importance of these parameters is illustrated on Salvia species native to Hungary.
Authors:Dénes Görög, Imre Fehérvári, Attila Doros, Balázs Nemes, Zoltán Máthé, László Kóbori and Jenő Járay
Májtranszplantáció után a graft subcapsularis haematomája és/vagy rupturája, mely kialakulhat spontán, sérülés vagy invazív radiológiai beavatkozásokat követően, ritkán előforduló, súlyos szövődmény. Szerzők 350 májátültetés során észlelt négy esetből három ismertetésével illusztrálják a szövődmény súlyosságát. Az első esetben graftbiopszia utáni álaneurysma halálos kimenetelű májrupturát eredményezett. A második esetben a donormáj felszínes sérülésének transzplantáció után mély ruptura lett a következménye, amely miatt májresectiót kellett végezni. A beteg septicus állapotban meghalt. A harmadik beteg műtét során észlelt subcapsularis haematomáját sikeresen kezelték, és a beteg meggyógyult. Eddigi tapasztalataik és az irodalmi ajánlások alapján a szerzők javaslatot fogalmaznak meg a műtét során keletkező májtok alatti vérömlenyek kezelésére, melynek lényegi részét képezi az argon-diathermia és a fibrinogennel és thrombinnal bevont kollagénszivacs alkalmazása.
Authors:Erzsébet Háznagy-Radnai, Petra Léber, Enikő Tóth, Gábor Janicsák and Imre Máthé
L. (Lamiaceae) contains the iridoids harpagide and acetylharpagide. The presence of other components, for example aucubin, can be revealed by TLC and RP HPLC. A readily applicable simple TLC-densitometric method for analysis of aqueous extracts of the plants has been established for comparative studies of aucubin-like iridoids in
Authors:Erzsébet Háznagy-Radnai, Klára Pintye-Hódi, Szilvia Czigle, Tamás Martinek, Gábor Janicsák, Imre Máthé and István Erős
We have isolated five iridoids (harpagide, acetylharpagide, harpagoside, ajugoside, and aucubin) from
L. by a combination of chromatographic methods-NP-TLC, RP-HPLC, and TLC-densitometry. The isolated iridoids were identified on the basis of their physical and spectroscopic properties. Basic information about their structures was obtained from their NMR spectra. X-ray fluorescence spectroscopy can be used for direct determination of inorganic elements in the leaves, stems, and inflorescences of
L. We identified K, Ca, Mo, Fe, Co, Ir, Ga, Tl, and S.