This study was undertaken to evaluate the antioxidant activity and cytotoxicity of Pleurotus cystidiosus, an edible mushroom, against Hep-2 cancer cells. Fresh P. cystidiosus mushroom was extracted with acetone (fraction A). Fraction A was extracted into hexane, dichloromethane and ethyl acetate successively and the remaining fraction was labeled as "A4". Fraction A4 was further separated into three fractions, A4-1, A4-2 and A4-3 using a reverse phase column. 1,1-diphenyl-2picrylhydrazyl (DPPH) radical scavenging activity and nitric oxide (NO) radical scavenging activity assays were used to investigate the reducing power of the extracts. The DPPH-EC 50 of A4-2 and A4-3 were 0.81 and 0.82 mg/mL, respectively; NO-EC 50 of A4-2 and A4-3 were 0.87 and 0.61 mg/mL, respectively. The results on cytotoxic effects based on MTT and LDH assays have shown that the same two extracts to have the highest activity. These results were reinforced by the cell morphological changes observed using an inverted fluorescence microscope of the treated cells. Cells incubated with the highest dose (5 mg/mL) of A4-2 and A4-3 showed cell morphological changes such as cellular swelling, irregular cell shapes, condensed cytoplasm and vacuolar areas. Hence it can be concluded that the extract of P. cystidiosus has antioxidative activity as well as cytotoxicity against Hep-2 cancer cells. It can also be speculated that the use of whole mushroom as a medicinal food may bring about health benefits.

Objectives:Acute paracetamol poisoning is an emerging problem in Sri Lanka. Management guidelines recommend ingested dose and serum paracetamol concentrations to assess the risk. Our aim was to determine the usefulness of the patient's history of an ingested dose of >150 mg/kg and paracetamol concentration obtained by a simple colorimetric method to assess risk in patients with acute paracetamol poisoning.Materials and Methods:Serum paracetamol concentrations were determined in 100 patients with a history of paracetamol overdose using High Performance Liquid Chromatography (HPLC); (reference method). The results were compared to those obtained with a colorimetric method. The utility of risk assessment by reported dose ingested and colorimetric analysis were compared.Results:The area under the receiver operating characteristic curve for the history of ingested dose was 0.578 and there was no dose cut-off providing useful risk categorization. Both analytical methods had less than 5% intra- and inter-batch variation and were accurate on spiked samples. The time from blood collection to result was six times faster and ten times cheaper for colorimetry (30 minutes, US$2) than for HPLC (180 minutes, US$20). The correlation coefficient between the paracetamol levels by the two methods was 0.85. The agreement on clinical risk categorization on the standard nomogram was also good (Kappa = 0.62, sensitivity 81%, specificity 89%).Conclusions:History of dose ingested alone greatly over-estimated the number of patients who need antidotes and it was a poor predictor of risk. Paracetamol concentrations by colorimetry are rapid and inexpensive. The use of these would greatly improve the assessment of risk and greatly reduce unnecessary expenditure on antidotes.

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Dengue infection is a major health care problem in tropical and subtropical countries. The recently approved dengue vaccine has limitations, and there is no antiviral drug for treatment at present.For centuries plants and plant extracts have been used in traditional medicine for the treatment of various infections. The whole plant of Munronia pinnata, which has been used for treating fever patients in Sri Lankan traditional medicine, was tested for anti-dengue viral activity.The cytotoxicity assay of M. pinnata on Vero cells using 4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) revealed Maximum Nontoxic Dose (MNTD) as 125 μg/ml and 50% cytotoxic concentration (CC50) as 428.9 ± 21.55 μg/ml. Plaque reduction antiviral assay performed on dengue-4 virus infected Vero cells demonstrated half-maximal inhibitory concentration (IC50) as 26.12 ± 0.91 μg/ml. The selectivity index (SI) of Dengue infection is a major health care problem in tropical and subtropical countries. The recently approved dengue vaccine has limitations, and there is no antiviral drug for treatment at present.For centuries plants and plant extracts have been used in traditional medicine for the treatment of various infections. The whole plant of Munronia pinnata, which has been used for treating fever patients in Sri Lankan traditional medicine, was tested for anti-dengue viral activity.The cytotoxicity assay of M. pinnata on Vero cells using 4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) revealed Maximum Nontoxic Dose (MNTD) as 125 μg/ml and 50% cytotoxic concentration (CC50) as 428.9 ± 21.55 μg/ml. Plaque reduction antiviral assay performed on dengue-4 virus infected Vero cells demonstrated half-maximal inhibitory concentration (IC50) as 26.12 ± 0.91 μg/ml. The selectivity index (SI) of M. pinnata was 16.42.Based on the selectivity index, Munronia pinnata appears to be a viable candidate for identifying biologically active compounds with anti-dengue viral activity.Keywords: Dengue, Munronia pinnata, Antiviral, Plaque reduction Assay, Vero Cells was 16.42.Based on the selectivity index, Munronia pinnata appears to be a viable candidate for identifying biologically active compounds with anti-dengue viral activity. Keywords: Dengue, Munronia pinnata, Antiviral, Plaque reduction Assay, Vero Cells

: The effect of tea brew on the excretion and tisue distribution of (~-m e t h~l -~~C ) caffeine was investigated. Following oral administration of 14 (I-methyl-C) caffeine t o male and female rats, the radioactivity was excreted (approx. 62% and 70% respectively) mainly in the urine, the greater part of t h e excretion occuring during 12 -24h period; small amounts (approx. 7% and 9% respectively) were found in the urine. In contrast, the oral administration of ( l -m e t l~~l -~~~) caffeine with tea brew resulted in an enhanced (approx. 70% and 78%) urinary excretion of radioactivity. The major urinary excretion again occuring during 1 2 -24h period. Major differences were apparent in the tissuedistribution studies. The radioactivity in the stomach declined faster when caffeine w q administered with tea than when pure caffeine was administered. In contrast, the radioactivity profile for blood showed a higher specific activity over a longer period when caffeine was administered with tea. The overall studies indicate that tea brew, probably reduce time uptake of caffeine and enhances urinary excredon.