Search results for "TOXICITY"

Evaluation of the acute toxicity, analgesic and CNS activities of different species ofTeucrium genus

1995

Methanol and dichloromethanol extracts of the leaves and stems of four Teucrium species (T. cartaginenses, T. flavum, T. pumillum and T. buxifolium) have been tested for their toxicity, analgesic and central depressor effects. The intraperitoneal administration of the different extracts showed a CNS depressant activity in mice, but they lacked anticonvulsive effects. When tested for analgesic activity none of the extracts increased the threshold of pain thermal stimulus. However, the methanol and dichloromethanol extracts of T. cartaginenses and T. buxifolium species showed a significant analgesic effect in models of pain induced by chemical or mechanical stimulation.

Dinoflagellates from marine algal blooms produce neurotoxic compounds: effects on free calcium levels in neuronal cells and synaptosomes

2000

In this report, evidence is presented that the marine unicellular eukaryotic dinoflagellates can cause neurotoxicity very likely by an increase in intracellular free calcium ions ([Ca(2+)](i)). Determinations of the effects of culture supernatants from different clones of the dinoflagellate Alexandrium sp. isolated from algal blooms on the viability of rat primary neuronal cells revealed that all clones tested were toxic for these cells. In addition, all Alexandrium clones tested, except for A. ostenfeldii BAH ME-141, were found to be toxic for rat pheochromocytoma PC12 cells. No toxicity was observed for culture supernatants from Gonyaulax and Coolia monotis. Calcium ions are important in …

Acute toxicity and bioaccumulation of endosulfan in rotifer (Brachionus calyciflorus).

1991

Abstract 1. 1. The acute toxicity of endosulfan was determined for the freshwater rotifer Brachionus calyciflorus . 2. 2. The mean 24 hr lc 50 value for endosulfan was 5.15 ppm with a coefficient of variation of 14.7%. 3. 3. Rotifers were exposed at two sublethal concentrations (1.5–2.0 ppm) of endosulfan for bioaccumulation experiments, for an exposure time of 24, 48, 72 and 96 hr. The rotifers were fed with Nannochloris oculata (5 × 10 5 cell/ml). 4. 4. The highest accumulation of endosulfan was found 24 hr after the start of the exposure to 1.5 ppm of the toxicant. A steady-state concentration in rotifer was reached between 24–48 hr, followed by a gradual decrease until 96 hr.

Metabolites from Combretum dolichopetalum and its associated endophytic fungus Nigrospora oryzae--Evidence for a metabolic partnership.

2015

Abstract A new altersolanol derivative, 4-dehydroxyaltersolanol A ( 9 ), along with two known sesquiterpenoids, ( S )-7′-hydroxyabscisic acid ( 7 ) and ( S )-abscisic acid ( 8 ) were obtained from the endophytic fungus, Nigrospora oryzae , isolated from leaves of Combretum dolichopetalum . The host plant yielded six known compounds including ellagic acid ( 1 ), 3, 3′, 4-tri-O-methylellagic acid ( 2 ), arjunolic acid ( 3 ), 4′-dihydrophaseic acid ( 4 ), echinulin ( 5 ) and arestrictin B ( 6 ). Close structural similarities with regard to compounds 4 , 7 and 8 were observed between the metabolites from the host plant and those of the endophytic fungus. Furthermore compounds 5 and 6 are relate…

Cytotoxic properties of Marrubium globosum ssp. libanoticum and its bioactive components

2013

Marrubium globosum Montbr. et Auch. ex Benth. ssp. libanoticum Boiss. (Lamiaceae) is a medicinal plant used in Lebanon for the treatment of inflammatory diseases, asthma, coughs and other pulmonary and urinary problems. The goal of our study was to assess the biological activity of M. globosum by testing different extracts of the aerial parts for their antiproliferative activity against human melanoma cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The chloroform fraction showed the greatest activity. The compounds isolated from the extracts were also tested: the mixture of (13 S)-9α,13α-epoxylabda-6β(19),16(15)-diol dilactone and (13 R)-9α,13α-epo…

Chemical characterisation and cytotoxicity evaluation of Convolvulus pluricaulis Sieb. ex Spreng. (Convolvulaceae) extracts towards sensitive and mul…

2016

Synthesis of hexahydrocyclopenta[ij]isoquinolines as a new class of dopaminergic agents.

2014

In this study, we have described the synthesis of the tricyclic 1,2,3,7,8,8a-hexahydrocyclopenta [ij]isoquinoline (HCPIQ). Herein, six differently substituted 5,6-dioxygenated-7-phenyl-HCPIQs have been synthesized using a new methodology via (E)-1-styryl-THIQ by Friedel-Crafts cyclization with Eaton's reagent. Results showed that HCPIQs (3, 3a-e) displayed a moderate affinity for D1 dopamine receptors (DR) in the micromolar range, furthermore the catecholic HCPIQs 3a (NH), 3c (NCH3) and 3e (NCH2CHCH2) exhibited outstanding affinity and high selectivity towards D2 DR. Indeed, 3a, 3c and 3e showed Ki values of 29 nM, 13 nM and 18 nM, respectively, and HCPIQs 3a (NH) and 3c (NCH3) displayed a …

Triterpene Saponins from the Roots of Achyranthes bidentata

2001

Three saponins, oleanolic acid-28- O -s-D-glucopyranoside (1), chikusetsusaponin V (2), and 3- O -s-D-glucopyranosyl-oleanolic acid-28- O -s-D-glucopyranoside (3) were isolated from the roots of Achyranthes bidentata Blume (Amaranthaceae). No activity was shown in the granulocyte phagocytosis test nor in the test of the potentiation of the cytotoxicity of cisplatin in human colon cancer cells. This is the first report of compounds 1, 2 and 3 isolated from Achyranthes species. Furthermore, the NMR data of 2 completed the partially published data.

Steroidal saponins from Chlorophytum deistelianum

2016

Abstract Phytochemical investigation of the aerial parts of Chlorophytum deistelianum led to the isolation of four previously undescribed steroidal saponins called chlorodeistelianosides A–D with five known ones. Their structures were established mainly by extensive 1D and 2D NMR spectroscopic techniques and mass spectrometry as (25R)-3β-[(β- d -glucopyranosyl-(1 → 3)-[α- l -rhamnopyranosyl-(1 → 4)]-β- d -xylopyranosyl-(1 → 3)-[β- d -glucopyranosyl-(1 → 2)]-β- d -glucopyranosyl-(1 → 4)-β- d -galactopyranosyl)oxy]-5α-spirostan-12-one, (24S,25S)-24-[(β- d -glucopyranosyl)oxy]-3β-[(β- d -glucopyranosyl-(1 → 2)-[β- d -xylopyranosyl-(1 → 3)]-β- d -glucopyranosyl-(1 → 4)-β- d -galactopyranosyl)ox…

Effect of Age on Systemic Exposure and Haematological Toxicity of Carboplatin in Advanced Non-Small Cell Lung Cancer Patients

2011

The aim of this study was to evaluate systemic exposure to carboplatin and its haematological toxicity in patients with advanced non-small cell lung cancer both older and younger than 70 years when the target area under the curve (AUC) in elderly patients was reduced by 20%. For this purpose, a population pharmacokinetic model was developed and the haema- tological toxicity of the drug was assessed. A total of 33 patients received carboplatin on day 1 and gemcitabine (1250 mg ⁄ m 2 ) on days 1 and 8. This schedule was repeated every 21 days. The Calvert-Crokcoft-Gault formula was employed to calculate a dose of carboplatin with a target AUC of 5 mg ⁄ min. ⁄ mL in patients under 70 years and…