From aerial parts of the fern Pteris multifida Poir. (Polypodiaceae) two diterpenes, entkaurane-2 beta, 16 alpha-diol and ent-kaur-16-ene-2 beta, 15 alpha-diol, were isolated by repeated column chromatography using silica gel and silica gel impregnated with silver nitrate. The structures were confirmed by spectroscopic methods. Both compounds showed a moderate cytotoxicity to Ehrlich ascites tu...

Six new ent-15-oxokauran-19-oic acid derivatives, named pterisolic acids A-F (1-6), were isolated from the ethanol extract of the fern Pteris semipinnata (Pteridaceae), and the structures of these new ent-kauranoids were elucidated on the basis of extensive spectroscopic studies and single crystal X-ray diffraction analysis.

visceral leishmanisasis is endemic and zoonotic in several foci in ardabil province, north west of iran. the main objective of this study was to determine the natural promastigote infection of sand-flies in active seasons, during 1991-1995. sand-flies were caught by sticky traps, aspirator and cdc light traps from indoors and outdoors. altogether 2659 sandflies were dissected and identified. th...

BACKGROUND Worldwide particularly in developing countries, a large proportion of the population is at risk for tropical parasitic diseases. Several medicinal plants are still used traditionally against protozoal infections in Yemen and Saudi Arabia. Thus the present study investigated the in vitro antiprotozoal activity of twenty-five plants collected from the Arabian Peninsula. METHODS Plant...

Brake fern, Pteris vittata, not only tolerates arsenic but also hyperaccumulates it in the frond. The hypothesis that arsenic hyperaccumulation in this fern could function as a defense against insect herbivory was tested. Fronds from control and arsenic-treated ferns were presented to nymphs of the grasshopper Schistocerca americana. Feeding damage was recorded by visual observation and quantif...

Autoradiographic localization of kainate binding sites has been determined in developing human and rat hippocampi. The results suggest differences. In particular, a transient high density of sites occurs in the supragranular layer of the fascia dentata of the human hippocampus.

Pteris vittata L., a fern was evaluated for its alpha amylase inhibitory potential owing to its previously reported antihyperglycemic activity. This Pteridophyte was also assayed for its free radical inhibition ability in ABTS decolourisation assay followed by quantification and HPTLC of polyphenols. The Porcine pancreatic alpha amylase inhibition was studied invitro and compared with standard ...

Genetic variation among 12 populations of the American chestnut (Castanea dentata) was investigated. Population genetic parameters estimated from allozyme variation suggest that C. dentata at both the population and species level has narrow genetic diversity as compared to other species in the genus. Average expected heterozygosity was relatively low for the population collected in the Black Ro...

Following prolonged stimulation of the perforant path input to the dentate gyrus, long-lasting changes occur in the synaptic responses and cell properties of cells in the fascia dentata. The present study describes the effects of sustained stimulation on the major population of cells innervated by the dentate granule cells: are CA3 pyramidal cells of hippocampus. In 46% of slices from rat, sust...

BACKGROUND & OBJECTIVES Conventional insecticides are generally used as larvicides to control Culex quinquefasciatus, vector of lymphatic filariasis. This study was undertaken to evaluate the larvicidal activity of some potential larvicidal plants leaf extracts against Cx. quinquefasciatus larvae. METHODS The toxic effects of petroleum ether leaf extracts of plants viz., Argemone mexicana (Me...