Metabotropic glutamate receptors (mGluRs) represent a potential therapeutic target. Possible anticonvulsant action of AMN 082, an agonist of mGluR7 subtype, was studied in immature rats using pentylenetetrazol (PTZ)-induced seizures as a model. Five age groups of rats (7-, 12-, 18-, 25-day-old and adult animals) were pretreated with AMN 082 in doses of 0.5, 1, 2, and 5 mg/kg i.p. and 30 min later PTZ was administered (100 mg/kg s.c.). Controls received saline instead of the agonist. AMN 082 did not exhibit clear anticonvulsant action with the exception of suppression of the tonic phase of generalized tonic-clonic seizures (GTCS) in 12-day-old rats. Shorter latencies of GTCS after AMN 082 pretreatment indicate a proconvulsant action. Involuntary movements (mostly tremor) appeared after AMN 082 before PTZ administration, therefore we performed another experimental series with AMN 082 only (1, 2, 5, and 10 mg/kg i.p.). During 60-min observation period tremor appeared in all age groups; sensitivity to this action decreased with age from the 2 mg/kg dose in 7- and 12-day-old rats to the 10 mg/kg dose in adult rats. Mixed anti- and proconvulsant actions of AMN 082 together with unwanted motor effects makes clinical use of this drug highly improbable., Pavel Mareš., and Obsahuje bibliografii a bibliografické odkazy
Three amoeba species were isolated from 3 out of 193 farmed tilapias, Oreochromis niloticus (L.), screened for the presence of free-living amoebae in parenchymatous organs. Hartmannella vermiformis Page, 1967 and Rosculus ithacus Hawes, 1963 were isolated from the kidney tissue. The third strain isolated from the liver shared morphological features of Mayorella and Platyamoeha spp. and therefore its taxonomic position has not been determined as yet. Pathogenicity of cloned strain of H. vermiformis was proved in two fish hosts.
Amoebae were found to cause severe gill tissue damage in turbot, Scophthalmus maximus L. from a grow-out facility in northwestern Galicia (Spain). The nature and extent of lesions along with negative results of bacteriological and virological examination made this agent responsible for mortalities in four turbot stocks supplied with water from a single source. We present our findings, although we failed to isolate amoebae, since there was a clear evidence of their primary role in the development of disease condition and occurrence of mortalities. In addition, this is a record both of a new host endangered by amoebae in intensive cultures and pathogenesis of the gill lesions.
Ninety four aquarium fishes were screened for the presence of amoebae in their internal organs. Five specimens of Ca-rassius auratus (L.) and one specimen of Xiphophorus hetleri Heckel were positive. Of the three strains which were isolated from C. auratus, successfully cloned and cultivated, one was identified as Vannella platypodia (Gläser, 1912) Page, 1976 and two strains as Rosculus ithacus Hawes, 1963. Both species are reported for the first time from organs of fish. None of them could be identified with the amoeba-like agent of goldfish granulomas described here.
From November 1997 to June 1998, 3,118 specimens of Echinogammarus stammeri (Karaman, 1931) (Amphipoda) were collected from the River Brenta (Northern Italy) and examined for larval helminths. Larvae of Polymorphus minuius (Goeze, 1782) singly infected the hemocoel of 23 (0.74%) crustaceans; all these larvae were cystacanth stages. This is the first record of Polymorphus minuius in E. stammeri. Some cystacanths had their forebody and hindbody fully inverted. Parasites were bright orange in colour and each was surrounded by a thin acellular envelope. This envelope likely protects the developing parasite larva from cellular responses of the amphipod. Hemocytes were seen adherent to the outer surface of the envelope. The sex ratio among the parasitised E. stammeri was almost 1:1. All Polymorphus minutus larvae were central in the amphipod body, made intimate contact with host internal organs, and frequently induced a marked displacement of them. None of the infected females of E. stammeri. carried eggs or juveniles in their brood pouch. In five hosts, Polymorphus minuius co-occurrcd with the cystacanth of another acanlhocephalan, Pomphorhynchus laevis (Millier, 1776), a parasite offish.
Knihovna Národního muzea Praha CZ Zámecká knihovna Mnichovo Hradiště, Knihovna Národního muzea Praha CZ 43 B 12, Národní knihovna ČR Praha CZ 46 A 129 adl. 2, Typis Vniverſitatis Carolo-Ferdinandeæ, in Collegio Societ: IESV ad S.Clementem., and BCBT42145
The object of the research was to investigate the spectral properties of Rayleigh-type surface waves, generated by shot-hole explosions during seismic refraction experiments which were carried out in the area of the Bohemian Massif and West Carpathians. The records of displacement amplitudes were spectrally analyzed and prevailing frequency fp, relative Δfr and absolute widths of the spectra Δfa were chosen as essential parameters. Whilst the prevailing frequencies were recorded within the interval f ÷ 0.80 - 3.70 Hz at the site of the observations, situated on the territory of the Bohemian Massif, the respecti ve frequency range f ÷ 0.80 - 2.6 Hz was found in the West Carpathians. Some functional dependences of the spectral amplitude parameters on epicentral distance were observed and regularities of their decrease were defined. Moreover, the influence of local seismogeological conditions at the shot point as well as at the site of observation occurred., Karel Holub., and Obsahuje bibliografické odkazy